subject:(Enantioselective)

1. Wang, Sa. Synthesis, Application, and Mechanistic Studies of the Asymmetric Addition of Organozinc Reagents to 3,4-Dihydroisoquinoline N-Oxide.

Degree: PhD, Chemistry, 2009, Brown University

URL: https://repository.library.brown.edu/studio/item/bdr:234/

► Tetrahydroisoquinolines (THIQ) are an important structural motif in many alkaloids, and they display significant biological and pharmacological properties. A majority of these compounds possess a… (more)

▼ Tetrahydroisoquinolines (THIQ) are an important structural motif in many alkaloids, and they display significant biological and pharmacological properties. A majority of these compounds possess a chiral center at the C-1 position, while stereoisomers at this position exhibit very different activities. Thus, the enantioselective synthesis of 1-substituted-THIQs is of great interest to both organic and medicinal chemists. In this thesis, we first report the enantioselective addition of vinylzinc reagents to 3,4-dihydroisoquinoline N-oxide. With an N-acylethylenediamine ligand as the catalyst, we obtained a group of chiral N-hydroxyl-1-vinyl-THIQs in 62-85% yield and 90-95% ee. A variety of aliphatic, cyclic and aromatic vinylzinc reagents were employed in the reaction. This method was used to synthesize a single enantiomer of the unnatural amino acid N-Cbz-D-1,2,3,4-tetrahydroisoquinoline-1-carboxylic acid. Next, we describe a novel, expedient synthesis of chiral 1-aryl-THIQs, in which the key step is the asymmetric addition of arylzinc reagents to 3,4-dihydroisoquinoline N-oxide catalyzed by the diamine ligand. With aryl pinacolyl boronic esters as arylzinc precursors, we achieved good yields (35-99%) and excellent enantioselectivities (97-99% ee) in the reaction. This methodology was demonstrated through the enantioselective synthesis of the GlaxoSmithKline drug ? Solifenacin. Finally, we investigated the mechanism of the enantioselective addition of arylzinc reagents to 3,4-dihydroisoquinoline N-oxide. We adopted a systematic strategy to study this complex system by using a wide range of NMR techniques. This includes, 1D and 2D NMR, Diffusion-Order NMR spectroscopy, Job plot, NMR titration, and in-situ NMR kinetic measurement. Through these studies, we obtained information about the structure and molecular interactions of reactive intermediates along the reaction pathway. We also found that the reaction occurs via a binuclear-zinc intermediate. Comparison of reaction rates showed that the catalyzed arylation reaction proceeds faster than the non-catalyzed process. Altogether, we propose a catalytic cycle for the asymmetric arylation reaction. The preference for formation of the (S)-product was rationalized by examining the conformations of different transition states. Advisors/Committee Members: Seto, Christopher (director), Williard, Paul (reader), Zimmt, Matthew (reader).

Subjects/Keywords: enantioselective synthesis

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APA (6^th Edition):

Wang, S. (2009). Synthesis, Application, and Mechanistic Studies of the Asymmetric Addition of Organozinc Reagents to 3,4-Dihydroisoquinoline N-Oxide. (Doctoral Dissertation). Brown University. Retrieved from https://repository.library.brown.edu/studio/item/bdr:234/

Chicago Manual of Style (16^th Edition):

Wang, Sa. “Synthesis, Application, and Mechanistic Studies of the Asymmetric Addition of Organozinc Reagents to 3,4-Dihydroisoquinoline N-Oxide.” 2009. Doctoral Dissertation, Brown University. Accessed April 13, 2021. https://repository.library.brown.edu/studio/item/bdr:234/.

MLA Handbook (7^th Edition):

Wang, Sa. “Synthesis, Application, and Mechanistic Studies of the Asymmetric Addition of Organozinc Reagents to 3,4-Dihydroisoquinoline N-Oxide.” 2009. Web. 13 Apr 2021.

Vancouver:

Wang S. Synthesis, Application, and Mechanistic Studies of the Asymmetric Addition of Organozinc Reagents to 3,4-Dihydroisoquinoline N-Oxide. [Internet] [Doctoral dissertation]. Brown University; 2009. [cited 2021 Apr 13]. Available from: https://repository.library.brown.edu/studio/item/bdr:234/.

Council of Science Editors:

Wang S. Synthesis, Application, and Mechanistic Studies of the Asymmetric Addition of Organozinc Reagents to 3,4-Dihydroisoquinoline N-Oxide. [Doctoral Dissertation]. Brown University; 2009. Available from: https://repository.library.brown.edu/studio/item/bdr:234/

Boston College

2. Zhang, Ping. Enantioselective Catalysis Through 3,3'-reductive Elimination of Unsaturated Allyl Metal Complexes.

Degree: PhD, Chemistry, 2012, Boston College

URL: http://dlib.bc.edu/islandora/object/bc-ir:101159

► This dissertation aims to design and develop novel and synthetically useful catalytic enantioselective C-C bond-forming reactions that employ a newly uncovered 3,3'-reductive elimination of bis(allyl)metal… (more)

Subjects/Keywords: Enantioselective catalysis

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APA (6^th Edition):

Zhang, P. (2012). Enantioselective Catalysis Through 3,3'-reductive Elimination of Unsaturated Allyl Metal Complexes. (Doctoral Dissertation). Boston College. Retrieved from http://dlib.bc.edu/islandora/object/bc-ir:101159

Chicago Manual of Style (16^th Edition):

Zhang, Ping. “Enantioselective Catalysis Through 3,3'-reductive Elimination of Unsaturated Allyl Metal Complexes.” 2012. Doctoral Dissertation, Boston College. Accessed April 13, 2021. http://dlib.bc.edu/islandora/object/bc-ir:101159.

MLA Handbook (7^th Edition):

Zhang, Ping. “Enantioselective Catalysis Through 3,3'-reductive Elimination of Unsaturated Allyl Metal Complexes.” 2012. Web. 13 Apr 2021.

Vancouver:

Zhang P. Enantioselective Catalysis Through 3,3'-reductive Elimination of Unsaturated Allyl Metal Complexes. [Internet] [Doctoral dissertation]. Boston College; 2012. [cited 2021 Apr 13]. Available from: http://dlib.bc.edu/islandora/object/bc-ir:101159.

Council of Science Editors:

Zhang P. Enantioselective Catalysis Through 3,3'-reductive Elimination of Unsaturated Allyl Metal Complexes. [Doctoral Dissertation]. Boston College; 2012. Available from: http://dlib.bc.edu/islandora/object/bc-ir:101159

Boston College

3. Lee, Jaehee. Expedient Synthesis of High-Value Organoboronates Through Catalytic Enantioselective Alkene Functionalization.

Degree: PhD, Chemistry, 2017, Boston College

URL: http://dlib.bc.edu/islandora/object/bc-ir:107696

► Chapter 1 Mechanism-Based Enhancement of Scope and Enantioselectivity for Reactions Involving a Copper-Substituted Stereogenic Carbon Center: Organoborons are important building blocks of complex natural products,… (more)

▼ Chapter 1 Mechanism-Based Enhancement of Scope and Enantioselectivity for Reactions Involving a Copper-Substituted Stereogenic Carbon Center: Organoborons are important building blocks of complex natural products, functional materials, and pharmaceutically relevant compounds due to their prevalent utility in C–C and C–hetero atom bond transformations. Using a readily accessible copper catalyst, we have developed highly site- and enantioselective allylic substitution by way of a threecomponent, single-vessel, and sustainable catalytic protocol. Detailed mechanistic studies revealed valuable insights which led us to develop copper–boron and copper–hydride additions to olefins with broader substrate scope, higher efficiency, and higher enantioselectivity. In addition, the method can be applied to the synthesis of biologically active molecules such as preclamol and heliespirone A and C. Chapter 2 Versatile Homoallylic Boronates by Chemo-, SN2’-, Diastereo- and Enantioselective Catalytic Sequence of Cu–H Addition to Vinyl-B(pin)/Allylic Substitution: To achieve an efficient multicomponent reaction, high chemoselectivity between a starting material and a reagent must be accomplished during the first catalytic transformation to generate an intermediate which then selectively reacts with another substrate to furnish the product in a site-, and/or stereoselective fashion. Development and application of efficient multicomponent reactions involving allylic substitution can provide alternative solutions for difficult synthetic problems in organic chemistry. Our group has developed a sulfonate-containing chiral NHC–Cu catalyzed chemo-, SN2’-, diastereo-, and enantioselective multicomponent reaction through Cu–H addition to readily available vinyl–B(pin) followed by allylic substitution to deliver homoallylic boronates. The derived homoallylic alcohols can be used as building blocks of biologically active molecules. Chapter 3 Enantioenriched Halogen-Substituted Alkenes through NHC–Cu-Catalyzed Borylation/Dehalogenation and Their Applications: Because of their unique properties, mono- and difluoroalkenes have received attention as an important class of compounds as building blocks for fluorine-containing monomers for functional polymers and biologically active molecules in medicine and agriculture. However, reported methods to prepare enantioenriched difluoroalkenes are scarce and often require undesirable amounts of precious transition metals and very high/low temperatures. To solve these challenges, we have developed a highly efficient, regio-, and enantioselective boron allylic substitution to CF3-alkenes and other halogen-substituted olefins by using an abundant copper-based catalyst. Advisors/Committee Members: Amir H. Hoveyda (Thesis advisor).

Subjects/Keywords: Enantioselective catalysis

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APA (6^th Edition):

Lee, J. (2017). Expedient Synthesis of High-Value Organoboronates Through Catalytic Enantioselective Alkene Functionalization. (Doctoral Dissertation). Boston College. Retrieved from http://dlib.bc.edu/islandora/object/bc-ir:107696

Chicago Manual of Style (16^th Edition):

Lee, Jaehee. “Expedient Synthesis of High-Value Organoboronates Through Catalytic Enantioselective Alkene Functionalization.” 2017. Doctoral Dissertation, Boston College. Accessed April 13, 2021. http://dlib.bc.edu/islandora/object/bc-ir:107696.

MLA Handbook (7^th Edition):

Lee, Jaehee. “Expedient Synthesis of High-Value Organoboronates Through Catalytic Enantioselective Alkene Functionalization.” 2017. Web. 13 Apr 2021.

Vancouver:

Lee J. Expedient Synthesis of High-Value Organoboronates Through Catalytic Enantioselective Alkene Functionalization. [Internet] [Doctoral dissertation]. Boston College; 2017. [cited 2021 Apr 13]. Available from: http://dlib.bc.edu/islandora/object/bc-ir:107696.

Council of Science Editors:

Lee J. Expedient Synthesis of High-Value Organoboronates Through Catalytic Enantioselective Alkene Functionalization. [Doctoral Dissertation]. Boston College; 2017. Available from: http://dlib.bc.edu/islandora/object/bc-ir:107696

University of Manchester

4. Page, Abigail. Atropisomeric Diaryl Ethers and other Non-Biaryl Atropisomers.

Degree: 2011, University of Manchester

URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:121988

► Atropisomerism is a property exhibited by molecules where rotation about one or more bonds is restricted. Along with biaryls, which are widely utilised in asymmetric… (more)

Subjects/Keywords: Atropisomer; enantioselective synthesis

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APA (6^th Edition):

Page, A. (2011). Atropisomeric Diaryl Ethers and other Non-Biaryl Atropisomers. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:121988

Chicago Manual of Style (16^th Edition):

Page, Abigail. “Atropisomeric Diaryl Ethers and other Non-Biaryl Atropisomers.” 2011. Doctoral Dissertation, University of Manchester. Accessed April 13, 2021. http://www.manchester.ac.uk/escholar/uk-ac-man-scw:121988.

MLA Handbook (7^th Edition):

Page, Abigail. “Atropisomeric Diaryl Ethers and other Non-Biaryl Atropisomers.” 2011. Web. 13 Apr 2021.

Vancouver:

Page A. Atropisomeric Diaryl Ethers and other Non-Biaryl Atropisomers. [Internet] [Doctoral dissertation]. University of Manchester; 2011. [cited 2021 Apr 13]. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:121988.

Council of Science Editors:

Page A. Atropisomeric Diaryl Ethers and other Non-Biaryl Atropisomers. [Doctoral Dissertation]. University of Manchester; 2011. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:121988

University of Utah

5. Jensen, Katrina Helen. Examination of catalyst and reactant electronic effects in enantioselective reactions.

Degree: PhD, Chemistry, 2010, University of Utah

URL: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/2019/rec/949

► Given the potential for opposite enantiomers of a chiral molecule to have different biological effects, access to a single enantiomer of a compound is desirable.… (more)

▼ Given the potential for opposite enantiomers of a chiral molecule to have different biological effects, access to a single enantiomer of a compound is desirable. Asymmetric catalysis is a powerful method for the synthesis of enantiomerically enriched chiral building blocks, and a mechanistic understanding of the relationship between catalyst structure and selectivity has the potential to advance the field. Additionally, mechanistic investigation provides insight about the nature of reactive intermediates, which allows one to imagine new ways to obtain or intercept such intermediates in the pursuit of new reaction development. Herein are described studies of two catalytic systems with a focus on mechanistic understanding. In the first system, a modular catalyst structure was used to systematically evaluate the effects of catalyst acidity in a hydrogen bond-catalyzed hetero Diels-Alder reaction. Linear free energy relationships between catalyst acidity and both rate and enantioselectivity were observed, where greater catalyst acidity leads to increased activity and selectivity. A relationship between reactant electronic nature and rate was also observed, although there is no such correlation to enantioselectivity, indicating the system is under catalyst control. In the second study, a unique approach to alkene difunctionalization was taken based on a mechanistic hypothesis of a quinone methide intermediate in a related reaction. Substrates containing an alkene adjacent to an ortho-phenol and a tethered nucleophile were prepared, allowing for the regioselective addition of two distinct nucleophiles. A key improvement to the catalytic system was achieved using a ligated copper cocatalyst, leading to improved reactivity without a detrimental effect on enantioselectivity. The reaction was applied to the dioxygenation and aminooxygenation of alkenes, resulting in the enantioselective formation of heterocyclic compounds bearing two adjacent chiral centers. The mechanism of the alkene difunctionalization reaction was studied using physical organic chemistry techniques. The proposed quinone methide intermediate was trapped in a Diels Alder reaction. Kinetic analysis provided evidence of rate limiting attack of this intermediate and for copper involvement in more than solely catalyst turnover. Through examination of substrate electronic effects a Jaffé relationship was observed correlating rate to electronic perturbation at two positions of the phenol. Ligand effects were evaluated to provide evidence of rapid ligand exchange and a direct correlation between ligand electronic nature and enantioselectivity.

Subjects/Keywords: Catalysis; Enantioselective; Organic chemistry

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APA (6^th Edition):

Jensen, K. H. (2010). Examination of catalyst and reactant electronic effects in enantioselective reactions. (Doctoral Dissertation). University of Utah. Retrieved from http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/2019/rec/949

Chicago Manual of Style (16^th Edition):

Jensen, Katrina Helen. “Examination of catalyst and reactant electronic effects in enantioselective reactions.” 2010. Doctoral Dissertation, University of Utah. Accessed April 13, 2021. http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/2019/rec/949.

MLA Handbook (7^th Edition):

Jensen, Katrina Helen. “Examination of catalyst and reactant electronic effects in enantioselective reactions.” 2010. Web. 13 Apr 2021.

Vancouver:

Jensen KH. Examination of catalyst and reactant electronic effects in enantioselective reactions. [Internet] [Doctoral dissertation]. University of Utah; 2010. [cited 2021 Apr 13]. Available from: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/2019/rec/949.

Council of Science Editors:

Jensen KH. Examination of catalyst and reactant electronic effects in enantioselective reactions. [Doctoral Dissertation]. University of Utah; 2010. Available from: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/2019/rec/949

University of Alberta

6. Takebayashi, Satoshi. Developments and Mechanistic Investigations of Ester, Imide, and Ketone Hydrogenations.

Degree: PhD, Department of Chemistry, 2012, University of Alberta

URL: https://era.library.ualberta.ca/files/vh53ww99b

► The Noyori-type catalyst trans-[Ru((R)-BINAP)(H)2((R,R)-dpen)] (6) and its analogues are among the most active and enantioselective ketone hydrogenation systems reported to date. Its applications towards other… (more)

▼ The Noyori-type catalyst trans-[Ru((R)-BINAP)(H)2((R,R)-dpen)] (6) and its analogues are among the most active and enantioselective ketone hydrogenation systems reported to date. Its applications towards other types of carbonyl compounds are, however, understudied. This dissertation describes the first applications of this catalyst system towards hydrogenations of esters and imides under mild reaction conditions. Further, a detailed mechanistic study of this system is presented using ketones, esters, and imides as substrates. The dihydride 6 was highly active towards the hydrogenation of esters. Stoichiometric reactions between 6 and lactones proceeded at –80 °C to form the net hydride insertion products, Ru-hemiacetaloxides. The hemiacetaloxides were further hydrogenated at –40 °C under ~2 atm of H2 to form the corresponding Ru-alkoxides. Catalytic hydrogenations could be carried out, even at –20 °C under 4 atm of H2, however, these hydrogenations slowed over time due to deactivation of the catalyst by primary alcohol products. The first homogeneous monohydrogenation of imides was developed using 6 and related compounds as catalysts. Further, upon optimization of reaction conditions and imide structure, meso-cyclic imides were desymmetrized in high ee via the monohydrogenation to form kinetically unfavoured trans-hydroxy lactams with up to 5 stereogenic centres. Furthermore, the number of stereogenic centres was increased from 5 to 7 using N-acyliminium ion chemistry. A model for the origin of enantioselection was proposed using substrate-catalyst steric interactions. Low temperature NMR studies revealed that base catalyzes the rapid cis-trans isomerization to form the thermodynamically more stable trans-isomer. It was proposed that this rapid isomerization prevents racemization of a product. Transition states for the formation of Ru-alkoxides from addition between 6 and acetophenone were studied using an intramolecular trapping experiment. Addition between 6 and 4-hydroxymethylacetophenone at –80 °C exclusively formed the net hydride insertion product, Ru-secondary-alkoxide. Combined with controlled experiments, this result is strong evidence for the formation of a Ru–O interaction in the transition state, which supports concerted formation of the Ru-alkoxides from 6 and acetophenone.

Subjects/Keywords: imide; ketone; enantioselective; hydrogenation; ester

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APA (6^th Edition):

Takebayashi, S. (2012). Developments and Mechanistic Investigations of Ester, Imide, and Ketone Hydrogenations. (Doctoral Dissertation). University of Alberta. Retrieved from https://era.library.ualberta.ca/files/vh53ww99b

Chicago Manual of Style (16^th Edition):

Takebayashi, Satoshi. “Developments and Mechanistic Investigations of Ester, Imide, and Ketone Hydrogenations.” 2012. Doctoral Dissertation, University of Alberta. Accessed April 13, 2021. https://era.library.ualberta.ca/files/vh53ww99b.

MLA Handbook (7^th Edition):

Takebayashi, Satoshi. “Developments and Mechanistic Investigations of Ester, Imide, and Ketone Hydrogenations.” 2012. Web. 13 Apr 2021.

Vancouver:

Takebayashi S. Developments and Mechanistic Investigations of Ester, Imide, and Ketone Hydrogenations. [Internet] [Doctoral dissertation]. University of Alberta; 2012. [cited 2021 Apr 13]. Available from: https://era.library.ualberta.ca/files/vh53ww99b.

Council of Science Editors:

Takebayashi S. Developments and Mechanistic Investigations of Ester, Imide, and Ketone Hydrogenations. [Doctoral Dissertation]. University of Alberta; 2012. Available from: https://era.library.ualberta.ca/files/vh53ww99b

University of Michigan

7. Hopkins, Brett A. Enantioselective Synthesis of Heterocycles via Palladium Catalyzed Alkene Difunctionalization Reactions.

Degree: PhD, Chemistry, 2015, University of Michigan

URL: http://hdl.handle.net/2027.42/113418

► Enantiopure nitrogen and oxygen containing heterocycles are prominently displayed in a variety of important pharmaceuticals and biologically active products. As such accessing these scaffolds in… (more)

▼ Enantiopure nitrogen and oxygen containing heterocycles are prominently displayed in a variety of important pharmaceuticals and biologically active products. As such accessing these scaffolds in an enantioselective and efficient manner is an interesting challenge. We envisioned that novel asymmetric carboamination and carboetherification reactions would be powerful methods to synthesize these enantiopure heterocycles, as you can generate a library of enantiopure compounds in a facile manner with this approach. While these enantioselective carboamination and carboetherification reactions are robust methods of accessing enantiopure heterocycles, at the onset of the work detailed in this thesis all of the efforts in this area were related to the formation of 5-membered rings bearing a single nitrogen heteroatom. As such, this thesis entails the development of new enantioselective carboamination and carboetherification reactions meant to address the above limitations. Chapter 2 details the development of an enantioselective carboamination reaction to access enantiopure imidazolidin-2-ones in up to 97:3 er. This work also shows how reaction conditions, namely the choice of aryl halide, use of water additive and substrate electronics, affect the final enantioselectivity observed in the products. Chapter 3 details the development of a general procedure to access tetrahydroquinolines, tetrahydroisoquinolines and tetrahydroquinoxalines all in > 95:5 er. Furthermore, these reactions in chapter 3 are rare transformations of this type that allow for the synthesis of quaternary centers in high enantioselectivity. Chapter 4 details the xiii development of a novel carboetherification reaction, and how using a modular TADDOL ligand scaffold allowed us to rationally design a ligand that afforded our desired products in >95:5 er. Lastly, Chapter 5 entails the initial results looking into the synthesis of enantiopure benzofused oxygen heterocycles. Advisors/Committee Members: Wolfe, John P. (committee member), Soellner, Matthew Bryan (committee member), McNeil, Anne Jennifer (committee member), Sanford, Melanie (committee member).

Subjects/Keywords: Enantioselective; Heterocycles; Chemistry; Science

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APA (6^th Edition):

Hopkins, B. A. (2015). Enantioselective Synthesis of Heterocycles via Palladium Catalyzed Alkene Difunctionalization Reactions. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/113418

Chicago Manual of Style (16^th Edition):

Hopkins, Brett A. “Enantioselective Synthesis of Heterocycles via Palladium Catalyzed Alkene Difunctionalization Reactions.” 2015. Doctoral Dissertation, University of Michigan. Accessed April 13, 2021. http://hdl.handle.net/2027.42/113418.

MLA Handbook (7^th Edition):

Hopkins, Brett A. “Enantioselective Synthesis of Heterocycles via Palladium Catalyzed Alkene Difunctionalization Reactions.” 2015. Web. 13 Apr 2021.

Vancouver:

Hopkins BA. Enantioselective Synthesis of Heterocycles via Palladium Catalyzed Alkene Difunctionalization Reactions. [Internet] [Doctoral dissertation]. University of Michigan; 2015. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/2027.42/113418.

Council of Science Editors:

Hopkins BA. Enantioselective Synthesis of Heterocycles via Palladium Catalyzed Alkene Difunctionalization Reactions. [Doctoral Dissertation]. University of Michigan; 2015. Available from: http://hdl.handle.net/2027.42/113418

University of Hyderabad

8. Rao, K Srinivasa. Enantioselective Synthesis Of Terpenes; _.

Degree: chemisry, 1992, University of Hyderabad

URL: http://shodhganga.inflibnet.ac.in/handle/10603/25363

Available in chapter

References is given in chapter

Advisors/Committee Members: Mehta, Goverdhan.

Subjects/Keywords: Enantioselective; Synthesis

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APA (6^th Edition):

Rao, K. S. (1992). Enantioselective Synthesis Of Terpenes; _. (Thesis). University of Hyderabad. Retrieved from http://shodhganga.inflibnet.ac.in/handle/10603/25363

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Rao, K Srinivasa. “Enantioselective Synthesis Of Terpenes; _.” 1992. Thesis, University of Hyderabad. Accessed April 13, 2021. http://shodhganga.inflibnet.ac.in/handle/10603/25363.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Rao, K Srinivasa. “Enantioselective Synthesis Of Terpenes; _.” 1992. Web. 13 Apr 2021.

Vancouver:

Rao KS. Enantioselective Synthesis Of Terpenes; _. [Internet] [Thesis]. University of Hyderabad; 1992. [cited 2021 Apr 13]. Available from: http://shodhganga.inflibnet.ac.in/handle/10603/25363.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Rao KS. Enantioselective Synthesis Of Terpenes; _. [Thesis]. University of Hyderabad; 1992. Available from: http://shodhganga.inflibnet.ac.in/handle/10603/25363

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Boston College

9. Fager, Diana Catherine. Catalytic Enantioselective Additions of Allyl Moieties to α-Halomethyl Ketones, Trifluoromethyl Substituted NH-Ketimines, and Nitriles.

Degree: PhD, Chemistry, 2020, Boston College

URL: http://dlib.bc.edu/islandora/object/bc-ir:108931

► Homoallylic alcohols and amines are commonly used building blocks for synthesis of biologically active molecules, yet a survey of the methods for their synthesis reveals… (more)

Subjects/Keywords: allylation; aminophenol; crotylation; enantioselective; regioselective

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APA (6^th Edition):

Fager, D. C. (2020). Catalytic Enantioselective Additions of Allyl Moieties to α-Halomethyl Ketones, Trifluoromethyl Substituted NH-Ketimines, and Nitriles. (Doctoral Dissertation). Boston College. Retrieved from http://dlib.bc.edu/islandora/object/bc-ir:108931

Chicago Manual of Style (16^th Edition):

Fager, Diana Catherine. “Catalytic Enantioselective Additions of Allyl Moieties to α-Halomethyl Ketones, Trifluoromethyl Substituted NH-Ketimines, and Nitriles.” 2020. Doctoral Dissertation, Boston College. Accessed April 13, 2021. http://dlib.bc.edu/islandora/object/bc-ir:108931.

MLA Handbook (7^th Edition):

Fager, Diana Catherine. “Catalytic Enantioselective Additions of Allyl Moieties to α-Halomethyl Ketones, Trifluoromethyl Substituted NH-Ketimines, and Nitriles.” 2020. Web. 13 Apr 2021.

Vancouver:

Fager DC. Catalytic Enantioselective Additions of Allyl Moieties to α-Halomethyl Ketones, Trifluoromethyl Substituted NH-Ketimines, and Nitriles. [Internet] [Doctoral dissertation]. Boston College; 2020. [cited 2021 Apr 13]. Available from: http://dlib.bc.edu/islandora/object/bc-ir:108931.

Council of Science Editors:

Fager DC. Catalytic Enantioselective Additions of Allyl Moieties to α-Halomethyl Ketones, Trifluoromethyl Substituted NH-Ketimines, and Nitriles. [Doctoral Dissertation]. Boston College; 2020. Available from: http://dlib.bc.edu/islandora/object/bc-ir:108931

Boston College

10. Alite, Hekla. Kinetic Resolution of Alcohols by Catalytic Enantioselective Sulfonylation and Silylation.

Degree: MS, Chemistry, 2012, Boston College

URL: http://dlib.bc.edu/islandora/object/bc-ir:101335

► Chapter 1: Brief overview of the catalytic enantioselective functionalization and kinetic resolution of alcohols Chapter 2: Kinetic resolution of syn-diols by catalytic enantioselective sulfonylation Chapter… (more)

Subjects/Keywords: enantioselective; kinetic resolution; silylation; sulfonylation

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APA (6^th Edition):

Alite, H. (2012). Kinetic Resolution of Alcohols by Catalytic Enantioselective Sulfonylation and Silylation. (Masters Thesis). Boston College. Retrieved from http://dlib.bc.edu/islandora/object/bc-ir:101335

Chicago Manual of Style (16^th Edition):

Alite, Hekla. “Kinetic Resolution of Alcohols by Catalytic Enantioselective Sulfonylation and Silylation.” 2012. Masters Thesis, Boston College. Accessed April 13, 2021. http://dlib.bc.edu/islandora/object/bc-ir:101335.

MLA Handbook (7^th Edition):

Alite, Hekla. “Kinetic Resolution of Alcohols by Catalytic Enantioselective Sulfonylation and Silylation.” 2012. Web. 13 Apr 2021.

Vancouver:

Alite H. Kinetic Resolution of Alcohols by Catalytic Enantioselective Sulfonylation and Silylation. [Internet] [Masters thesis]. Boston College; 2012. [cited 2021 Apr 13]. Available from: http://dlib.bc.edu/islandora/object/bc-ir:101335.

Council of Science Editors:

Alite H. Kinetic Resolution of Alcohols by Catalytic Enantioselective Sulfonylation and Silylation. [Masters Thesis]. Boston College; 2012. Available from: http://dlib.bc.edu/islandora/object/bc-ir:101335

Boston College

11. Radomkit, Suttipol. New Concepts, Catalysts, and Methods for Enantioselective Synthesis of C-B and C-C Bonds.

Degree: PhD, Chemistry, 2016, Boston College

URL: http://dlib.bc.edu/islandora/object/bc-ir:107272

► Chapter 1. Part A: N-Heterocyclic Carbenes Catalyzed Enantioselective Boryl Conjugate Additions to α,β-Unsaturated Ketones, Esters, Weinreb Amides and Aldehydes. The first broadly applicable enantioselective boryl… (more)

▼ Chapter 1. Part A: N-Heterocyclic Carbenes Catalyzed Enantioselective Boryl Conjugate Additions to α,β-Unsaturated Ketones, Esters, Weinreb Amides and Aldehydes. The first broadly applicable enantioselective boryl conjugate addition reactions to a variety of α,β-unsaturated carbonyls are reported. Transformations are promoted by 5.0 mol % of a chiral Lewis basic N-heterocyclic carbene. The distinctive feature of the reactions in chemoselectivity of the method compared to the Cu-catalyzed variants has been illustrated. Part B: Enantioselective Synthesis of Boron-Substituted Quaternary Carbon Stereogenic Centers through N-Heterocyclic Carbenes Catalyzed Boryl Conjugate Additions to Cyclic and Acyclic Enones The first examples of Lewis base catalyzed enantioselective boryl conjugate additions that afford products containing boron-substituted quaternary carbon stereogenic centers are presented. The carbon–boron bond forming reactions are promoted by 1.0–5.0 mol % of a chiral N–hererocyclic carbene. Cyclic or linear α,β–unsaturated ketones can be used as suitable substrates and the desired products are obtained in 63–95% yield and 91:9 to >99:1 enantiomeric ratio. The utility of the Lewis base-catalyzed approach is demonstrated in the context of an enantioselective formal synthesis of antifungal natural product crassinervic acid. Chapter 2. Enantioselectivity Fluctuations in Phosphine–Cu-Catalyzed Enantioselective Boron-Allyl Addition to Aryl-Substituted Olefins. Catalytic enantioselective multicomponent processes involving B2(pin)2, aryl or heteroaryl monosubstituted olefins, and allylic phosphates or carbonates are disclosed. Transformations promoted by a chiral Cu–phosphine complex afford products that contain a primary C–B(pin) bond and an allyl-substituted tertiary carbon stereogenic center in up to 84% yield and 98:2 enantiomeric ratio. The utility of the approach is showcased in the enantioselective formal synthesis of biologically active heliespirones A and C. Based on mechanistic and computational studies, we show that enantioselectivities variations can depend on electronic and/or steric factors of the alkene substrate and the allyl electrophile as well as their concentration. In most cases, selectivity loss can be minimized and that the resulting insights are also applicable to reactions involving Cu–H species. Chapter 3. Synthesis of Vicinal Diboronate Compounds through Practical Phosphine–Copper Catalyzed Three-Component Processes. The phosphine–Cu-catalyzed multicomponent processes have been developed for a practical and direct synthesis of vicinal diboronate compounds. Reactions of alkenyl–boronates, allylic phosphates, and diboron reagents are promoted by 2.5–10 mol % of a Cy3P–Cu complex affording a wide range of desirable vicinal diboronate products. The ability for easy access to either regioisomers of the products with a C–B(pin) and an adjacent C–B(dan) bond that can be site-selectively functionalized is a noteworthy feature of the method. Advisors/Committee Members: Amir H. Hoveyda (Thesis advisor).

Subjects/Keywords: Boron; Carbon; Enantioselective Synthesis

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APA (6^th Edition):

Radomkit, S. (2016). New Concepts, Catalysts, and Methods for Enantioselective Synthesis of C-B and C-C Bonds. (Doctoral Dissertation). Boston College. Retrieved from http://dlib.bc.edu/islandora/object/bc-ir:107272

Chicago Manual of Style (16^th Edition):

Radomkit, Suttipol. “New Concepts, Catalysts, and Methods for Enantioselective Synthesis of C-B and C-C Bonds.” 2016. Doctoral Dissertation, Boston College. Accessed April 13, 2021. http://dlib.bc.edu/islandora/object/bc-ir:107272.

MLA Handbook (7^th Edition):

Radomkit, Suttipol. “New Concepts, Catalysts, and Methods for Enantioselective Synthesis of C-B and C-C Bonds.” 2016. Web. 13 Apr 2021.

Vancouver:

Radomkit S. New Concepts, Catalysts, and Methods for Enantioselective Synthesis of C-B and C-C Bonds. [Internet] [Doctoral dissertation]. Boston College; 2016. [cited 2021 Apr 13]. Available from: http://dlib.bc.edu/islandora/object/bc-ir:107272.

Council of Science Editors:

Radomkit S. New Concepts, Catalysts, and Methods for Enantioselective Synthesis of C-B and C-C Bonds. [Doctoral Dissertation]. Boston College; 2016. Available from: http://dlib.bc.edu/islandora/object/bc-ir:107272

Boston College

12. Moebius, David Charles. Development of Sc(III)-catalyzed Homologation of Ketones by Non-stabilized Diazomethanes.

Degree: PhD, Chemistry, 2011, Boston College

URL: http://dlib.bc.edu/islandora/object/bc-ir:101506

► The research of diazoalkanes dates back more than 100 years, yet a disproportionally small number of methods have been developed to utilize their unique reactivity… (more)

Subjects/Keywords: catalysis; enantioselective; homologation; insertion; scandium

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APA (6^th Edition):

Moebius, D. C. (2011). Development of Sc(III)-catalyzed Homologation of Ketones by Non-stabilized Diazomethanes. (Doctoral Dissertation). Boston College. Retrieved from http://dlib.bc.edu/islandora/object/bc-ir:101506

Chicago Manual of Style (16^th Edition):

Moebius, David Charles. “Development of Sc(III)-catalyzed Homologation of Ketones by Non-stabilized Diazomethanes.” 2011. Doctoral Dissertation, Boston College. Accessed April 13, 2021. http://dlib.bc.edu/islandora/object/bc-ir:101506.

MLA Handbook (7^th Edition):

Moebius, David Charles. “Development of Sc(III)-catalyzed Homologation of Ketones by Non-stabilized Diazomethanes.” 2011. Web. 13 Apr 2021.

Vancouver:

Moebius DC. Development of Sc(III)-catalyzed Homologation of Ketones by Non-stabilized Diazomethanes. [Internet] [Doctoral dissertation]. Boston College; 2011. [cited 2021 Apr 13]. Available from: http://dlib.bc.edu/islandora/object/bc-ir:101506.

Council of Science Editors:

Moebius DC. Development of Sc(III)-catalyzed Homologation of Ketones by Non-stabilized Diazomethanes. [Doctoral Dissertation]. Boston College; 2011. Available from: http://dlib.bc.edu/islandora/object/bc-ir:101506

Columbia University

13. Gheewala, Chirag. Enantioselective Brønsted Acid Catalysis with Chiral Pentacarboxycyclopentadienes.

Degree: 2017, Columbia University

URL: https://doi.org/10.7916/D8QN6K5N

► This thesis details the design and development of pentacarboxycyclopentadienes (PCCPs) as a new platform for enantioselective Brønsted acid catalysis. Prior to this research, enantioselective Brønsted… (more)

▼ This thesis details the design and development of pentacarboxycyclopentadienes (PCCPs) as a new platform for enantioselective Brønsted acid catalysis. Prior to this research, enantioselective Brønsted acid catalysis was limited to the BINOL (and variations thereof) framework. While this catalyst platform has paved the way for a myriad of novel asymmetric chemical transformations, the utility of this catalyst scaffold has suffered from its lengthy and expensive preparations. As an alternative, starting from readily available 1,2,3,4,5-pentacarbomethoxycyclopentadiene and various chiral alcohols and amines, the synthesis of a library of strongly acidic chiral catalysts is described. The utility of these novel acid catalysts is explored in various transformations. As a prelude to the heart of this work, Chapter 1 focuses on the advancements made in asymmetric Brønsted acid catalysis through BINOL-phosphate derived catalysts, focusing on the major accomplishments made by researchers since 2004. The provided review highlights the utility of these chiral acid catalysts but also reveals the need for a new scaffold that is more affordable and accessible. Chapter 2 discusses the background of PCCPs, including its initial discovery and subsequent applications. Our work in developing novel transesterified and amidated derivatives is discussed with accompanying crystal structures of achiral and chiral PCCPs. pKa measurements demonstrate the capacity of PCCPs to be used as strong Brønsted acid catalysts and are compared to literature values of known Brønsted acid catalysts. Chapter 3 focuses on the utility of PCCPs as enantioselective Brønsted acid catalysts in a variety of chemical transformations including the Mukaiyama-Mannich reaction, transfer hydrogenation, Pictet-Spengler reaction, diaryl alcohol substitution, Mukayaiama oxocarbenium aldol reaction, and [4+2]-cycloaddition. Catalyst loadings down to 0.01 mol% and reaction scale up to 25 grams in the Mukaiyama-Mannich reaction demonstrate the practical utility and robustness of PCCPs. Substrate scopes of these transformations show the breadth of accessible molecules that can be synthesized via PCCPs. Mechanistic rationales and transition state analyses are discussed in each of the transformations.

Subjects/Keywords: Chemistry; Chemistry, Organic; Enantioselective catalysis

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APA (6^th Edition):

Gheewala, C. (2017). Enantioselective Brønsted Acid Catalysis with Chiral Pentacarboxycyclopentadienes. (Doctoral Dissertation). Columbia University. Retrieved from https://doi.org/10.7916/D8QN6K5N

Chicago Manual of Style (16^th Edition):

Gheewala, Chirag. “Enantioselective Brønsted Acid Catalysis with Chiral Pentacarboxycyclopentadienes.” 2017. Doctoral Dissertation, Columbia University. Accessed April 13, 2021. https://doi.org/10.7916/D8QN6K5N.

MLA Handbook (7^th Edition):

Gheewala, Chirag. “Enantioselective Brønsted Acid Catalysis with Chiral Pentacarboxycyclopentadienes.” 2017. Web. 13 Apr 2021.

Vancouver:

Gheewala C. Enantioselective Brønsted Acid Catalysis with Chiral Pentacarboxycyclopentadienes. [Internet] [Doctoral dissertation]. Columbia University; 2017. [cited 2021 Apr 13]. Available from: https://doi.org/10.7916/D8QN6K5N.

Council of Science Editors:

Gheewala C. Enantioselective Brønsted Acid Catalysis with Chiral Pentacarboxycyclopentadienes. [Doctoral Dissertation]. Columbia University; 2017. Available from: https://doi.org/10.7916/D8QN6K5N

University of Manchester

14. Page, Abigail. Atropisomeric diaryl ethers and other non-biaryl atropisomers.

Degree: PhD, 2011, University of Manchester

URL: https://www.research.manchester.ac.uk/portal/en/theses/atropisomeric-diaryl-ethers-and-other-nonbiaryl-atropisomers(84281e1e-416b-4d2e-834b-1d215d6767cf).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.538368

► Atropisomerism is a property exhibited by molecules where rotation about one or more bonds is restricted. Along with biaryls, which are widely utilised in asymmetric… (more)

Subjects/Keywords: 547.1223; Atropisomer; enantioselective synthesis

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APA (6^th Edition):

Page, A. (2011). Atropisomeric diaryl ethers and other non-biaryl atropisomers. (Doctoral Dissertation). University of Manchester. Retrieved from https://www.research.manchester.ac.uk/portal/en/theses/atropisomeric-diaryl-ethers-and-other-nonbiaryl-atropisomers(84281e1e-416b-4d2e-834b-1d215d6767cf).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.538368

Chicago Manual of Style (16^th Edition):

Page, Abigail. “Atropisomeric diaryl ethers and other non-biaryl atropisomers.” 2011. Doctoral Dissertation, University of Manchester. Accessed April 13, 2021. https://www.research.manchester.ac.uk/portal/en/theses/atropisomeric-diaryl-ethers-and-other-nonbiaryl-atropisomers(84281e1e-416b-4d2e-834b-1d215d6767cf).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.538368.

MLA Handbook (7^th Edition):

Page, Abigail. “Atropisomeric diaryl ethers and other non-biaryl atropisomers.” 2011. Web. 13 Apr 2021.

Vancouver:

Page A. Atropisomeric diaryl ethers and other non-biaryl atropisomers. [Internet] [Doctoral dissertation]. University of Manchester; 2011. [cited 2021 Apr 13]. Available from: https://www.research.manchester.ac.uk/portal/en/theses/atropisomeric-diaryl-ethers-and-other-nonbiaryl-atropisomers(84281e1e-416b-4d2e-834b-1d215d6767cf).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.538368.

Council of Science Editors:

Page A. Atropisomeric diaryl ethers and other non-biaryl atropisomers. [Doctoral Dissertation]. University of Manchester; 2011. Available from: https://www.research.manchester.ac.uk/portal/en/theses/atropisomeric-diaryl-ethers-and-other-nonbiaryl-atropisomers(84281e1e-416b-4d2e-834b-1d215d6767cf).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.538368

University of Edinburgh

15. Roy, Iain David. The development of novel enantioselective transition metal-catalysed 1,4- and 1,6-additions.

Degree: PhD, 2015, University of Edinburgh

URL: http://hdl.handle.net/1842/17921

► 1. ENANTIOSELECTIVE RHODIUM-CATALYSED 1,4-ARYLATION OF ALKENYLAZAARENES An extended study on the enantioselective rhodium-catalysed 1,4-arylation of alkenylazaarenes has been conducted. The 1,4-arylation of various alkenylazaarenes was… (more)

▼ 1. ENANTIOSELECTIVE RHODIUM-CATALYSED 1,4-ARYLATION OF ALKENYLAZAARENES An extended study on the enantioselective rhodium-catalysed 1,4-arylation of alkenylazaarenes has been conducted. The 1,4-arylation of various alkenylazaarenes was performed with an extended range of arylboronic acids using a modified catalytic system with a superior chiral diene ligand. The result is the generation of a large number of b-stereocentre-containing azaarene compounds in high enantiopurity. Further studies also enabled the completion of a reactivity index between alkenylazaarenes and more traditional α,β-unsaturated carbonyl compounds and the incorporation of the arylation into arylation-aldol domino processes. 2. ENANTIOSELECTIVE RHODIUM-CATALYSED 1,4-ALKENYLATION OF ALKENYLAZAARENES An extensive study on the enantioselective rhodium-catalysed 1,4-alkenylation of alkenylazaarenes has been performed. Development of the reaction parameters identified novel heterogeneous reaction conditions in pure water with sub-stoichiometric SDS. Subsequent ligand development identified an anilide-based chiral diene that provided the best balance between conversion and enantiopurity. Using the novel conditions, a selection of alkenylazaarenes underwent enantioselective rhodium-catalysed 1,4-alkenylation with two alkenyl MIDA boronates to provide the alkenylation products in good to excellent yields and moderate to excellent enantioselectivities. 3. ENANTIOSELECTIVE COPPER-CATALYSED 1,6-BORATION OF ELECTRON-DEFICIENT DIENES The development of an enantioselective copper-catalysed 1,6-boration of electrondeficient dienes using B2(pin)2 has been achieved. The reactions provide chiral allylboronic esters that, after oxidation, result in secondary allylic alcohols in moderate to high yields with excellent enantioselectivities and 1,6:1,4-regioselectivities. The 1,6-borations proceed efficiently employing catalyst loadings as low as 0.0049 mol% and their scalability has been demonstrated up to 40.4 mmol. The methodology was applied to a concise synthesis of atorvastatin, in which the key 1,6-boration was performed using a catalyst loading of 0.02 mol%.

Subjects/Keywords: 541; enantioselective; transition metal

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APA (6^th Edition):

Roy, I. D. (2015). The development of novel enantioselective transition metal-catalysed 1,4- and 1,6-additions. (Doctoral Dissertation). University of Edinburgh. Retrieved from http://hdl.handle.net/1842/17921

Chicago Manual of Style (16^th Edition):

Roy, Iain David. “The development of novel enantioselective transition metal-catalysed 1,4- and 1,6-additions.” 2015. Doctoral Dissertation, University of Edinburgh. Accessed April 13, 2021. http://hdl.handle.net/1842/17921.

MLA Handbook (7^th Edition):

Roy, Iain David. “The development of novel enantioselective transition metal-catalysed 1,4- and 1,6-additions.” 2015. Web. 13 Apr 2021.

Vancouver:

Roy ID. The development of novel enantioselective transition metal-catalysed 1,4- and 1,6-additions. [Internet] [Doctoral dissertation]. University of Edinburgh; 2015. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/1842/17921.

Council of Science Editors:

Roy ID. The development of novel enantioselective transition metal-catalysed 1,4- and 1,6-additions. [Doctoral Dissertation]. University of Edinburgh; 2015. Available from: http://hdl.handle.net/1842/17921

University of Edinburgh

16. Hepburn, Hamish Bruce. Enantioselective rhodium-catalysed nucleophilic allylation of cyclic imines.

Degree: PhD, 2015, University of Edinburgh

URL: http://hdl.handle.net/1842/17614

► A highly enantioselective and diastereoselective rhodium-catalysed addition of potassium allyltrifluoroborates to cyclic imines is described within. By utilising rhodium-chiral diene complexes, a wide range of… (more)

Subjects/Keywords: 546; rhodium; enantioselective; diene

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APA (6^th Edition):

Hepburn, H. B. (2015). Enantioselective rhodium-catalysed nucleophilic allylation of cyclic imines. (Doctoral Dissertation). University of Edinburgh. Retrieved from http://hdl.handle.net/1842/17614

Chicago Manual of Style (16^th Edition):

Hepburn, Hamish Bruce. “Enantioselective rhodium-catalysed nucleophilic allylation of cyclic imines.” 2015. Doctoral Dissertation, University of Edinburgh. Accessed April 13, 2021. http://hdl.handle.net/1842/17614.

MLA Handbook (7^th Edition):

Hepburn, Hamish Bruce. “Enantioselective rhodium-catalysed nucleophilic allylation of cyclic imines.” 2015. Web. 13 Apr 2021.

Vancouver:

Hepburn HB. Enantioselective rhodium-catalysed nucleophilic allylation of cyclic imines. [Internet] [Doctoral dissertation]. University of Edinburgh; 2015. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/1842/17614.

Council of Science Editors:

Hepburn HB. Enantioselective rhodium-catalysed nucleophilic allylation of cyclic imines. [Doctoral Dissertation]. University of Edinburgh; 2015. Available from: http://hdl.handle.net/1842/17614

University of Illinois – Urbana-Champaign

17. Roth, Aaron. Stereoselective synthesis of 1,2-disubstitued βeta-amino alcohols and amino thiols.

Degree: PhD, Chemistry, 2020, University of Illinois – Urbana-Champaign

URL: http://hdl.handle.net/2142/108470

► This thesis covers the development and implementation of two distinct methodologies, both of which provide access to enantiomerically enriched, vicinally functionalized products. Chapter 1 provides… (more)

Subjects/Keywords: Lewis base Catalysis; Stereoselective; Enantioselective

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APA (6^th Edition):

Roth, A. (2020). Stereoselective synthesis of 1,2-disubstitued βeta-amino alcohols and amino thiols. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/108470

Chicago Manual of Style (16^th Edition):

Roth, Aaron. “Stereoselective synthesis of 1,2-disubstitued βeta-amino alcohols and amino thiols.” 2020. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed April 13, 2021. http://hdl.handle.net/2142/108470.

MLA Handbook (7^th Edition):

Roth, Aaron. “Stereoselective synthesis of 1,2-disubstitued βeta-amino alcohols and amino thiols.” 2020. Web. 13 Apr 2021.

Vancouver:

Roth A. Stereoselective synthesis of 1,2-disubstitued βeta-amino alcohols and amino thiols. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2020. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/2142/108470.

Council of Science Editors:

Roth A. Stereoselective synthesis of 1,2-disubstitued βeta-amino alcohols and amino thiols. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2020. Available from: http://hdl.handle.net/2142/108470

University of Florida

18. Mishra, Sourabh. Facile Tuning of Atropisomeric P,N-Ligands towards Efficient Enantioselective Catalysis.

Degree: PhD, Chemistry, 2019, University of Florida

URL: https://ufdc.ufl.edu/UFE0052900

► Asymmetric catalysis is an important tool in the assembly of chiral compounds and the development of new chiral ligands is essential for efficient asymmetric induction.… (more)

Subjects/Keywords: aponickgroup – catalysis – enantioselective – liganddesign – stackphos

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APA (6^th Edition):

Mishra, S. (2019). Facile Tuning of Atropisomeric P,N-Ligands towards Efficient Enantioselective Catalysis. (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0052900

Chicago Manual of Style (16^th Edition):

Mishra, Sourabh. “Facile Tuning of Atropisomeric P,N-Ligands towards Efficient Enantioselective Catalysis.” 2019. Doctoral Dissertation, University of Florida. Accessed April 13, 2021. https://ufdc.ufl.edu/UFE0052900.

MLA Handbook (7^th Edition):

Mishra, Sourabh. “Facile Tuning of Atropisomeric P,N-Ligands towards Efficient Enantioselective Catalysis.” 2019. Web. 13 Apr 2021.

Vancouver:

Mishra S. Facile Tuning of Atropisomeric P,N-Ligands towards Efficient Enantioselective Catalysis. [Internet] [Doctoral dissertation]. University of Florida; 2019. [cited 2021 Apr 13]. Available from: https://ufdc.ufl.edu/UFE0052900.

Council of Science Editors:

Mishra S. Facile Tuning of Atropisomeric P,N-Ligands towards Efficient Enantioselective Catalysis. [Doctoral Dissertation]. University of Florida; 2019. Available from: https://ufdc.ufl.edu/UFE0052900

University of Oxford

19. Thomas, Palacin. Rapid synthesis of the Taxol core.

Degree: PhD, 2020, University of Oxford

URL: http://ora.ox.ac.uk/objects/uuid:e3e923a0-c1fb-4962-b03d-c58f95807f47 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.800117

► This thesis describes the combination of prochiral/racemic electrophiles and non-stabilised nucleophiles in transition metal catalysed asymmetric transformations. The first part of the thesis focuses on… (more)

Subjects/Keywords: Total synthesis; Enantioselective catalysis

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APA (6^th Edition):

Thomas, P. (2020). Rapid synthesis of the Taxol core. (Doctoral Dissertation). University of Oxford. Retrieved from http://ora.ox.ac.uk/objects/uuid:e3e923a0-c1fb-4962-b03d-c58f95807f47 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.800117

Chicago Manual of Style (16^th Edition):

Thomas, Palacin. “Rapid synthesis of the Taxol core.” 2020. Doctoral Dissertation, University of Oxford. Accessed April 13, 2021. http://ora.ox.ac.uk/objects/uuid:e3e923a0-c1fb-4962-b03d-c58f95807f47 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.800117.

MLA Handbook (7^th Edition):

Thomas, Palacin. “Rapid synthesis of the Taxol core.” 2020. Web. 13 Apr 2021.

Vancouver:

Thomas P. Rapid synthesis of the Taxol core. [Internet] [Doctoral dissertation]. University of Oxford; 2020. [cited 2021 Apr 13]. Available from: http://ora.ox.ac.uk/objects/uuid:e3e923a0-c1fb-4962-b03d-c58f95807f47 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.800117.

Council of Science Editors:

Thomas P. Rapid synthesis of the Taxol core. [Doctoral Dissertation]. University of Oxford; 2020. Available from: http://ora.ox.ac.uk/objects/uuid:e3e923a0-c1fb-4962-b03d-c58f95807f47 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.800117

Boston College

20. van der Mei, Farid Willem. Proton-Activated Catalysts for Efficient and Practical Enantioselective Syntheses.

Degree: PhD, Chemistry, 2018, Boston College

URL: http://dlib.bc.edu/islandora/object/bc-ir:108140

► A previously developed catalytic system which can catalyze a variety of efficient and enantioselective allyl additions has been expanded to include regio-, diastereo-, Z-, and… (more)

▼ A previously developed catalytic system which can catalyze a variety of efficient and enantioselective allyl additions has been expanded to include regio-, diastereo-, Z-, and enantioselective crotyl addition reactions. As discussed in Chapter 1, we were able to carry out efficient crotyl additions to N-phosphinoyl imines by discovering a sufficiently Lewis acidic co-catalyst, zinc(II) methoxide. This finding enabled us to vastly improve reaction efficiency, in addition to enabling a 1,3-borotropic shift during the course of the reaction, turning a previously α selective transformation into a γ-selective one. These findings allowed us to develop a catalytic, enantioselective crotyl addition to N-phosphinoyl imines utilizing the commercially available Z-crotyl–B(pin). When the reaction conditions elucidated for crotyl additions to imines were utilized on a more electrophilic substrate, such as trifluoromethyl ketones, an entirely different finding was observed (Chapter 2). We found that if direct addition is more facile than 1,3-borotropic shift the transformation will again be α-selective, furnishing a linear product, rather than the typically observed, branched crotyl addition product. This finding allowed us to establish the first broadly applicable, efficient, regio-, Z-, and enantioselective crotyl addition to trifluoromethyl ketones. We then highlighted the utility of these products by using this method in tandem with Z-selective olefin metathesis, affording complex, enantioenriched, trifluoromethyl-containing homoallylic alcohols. During the course of these studies, and through density functional theory computations, we learned that Z- and E-crotyl–B(pin) react through distinct transition states to form the same Z-olefin-containing product with varying levels of enantioselectivity. These findings led us to the results reported in Chapter 3, the first examples of enantioselective aminophenol-promoted allyl additions to aldehydes. We were able to utilize Z-CF3-allyl–B(pin) and Z-Cl-allyl–B(pin) (both accessed through catalytic olefin metathesis) in Z- and enantioselective additions to aldehydes, affording products which cannot be accessed readily through previously reported methods. We quickly realized the potential of Z-chloro-substituted homoallylic alcohols for the synthesis of Z-homoallylic alcohols, to demonstrate this potential, we carried out the total synthesis of mycothiazole, which we accomplished in seven steps from commercially available materials and 17% overall yield, a marked improvement over the previous synthetic strategy. Advisors/Committee Members: Amir H. Hoveyda (Thesis advisor).

Subjects/Keywords: Allylation; Aminophenol; Crotylation; Enantioselective; Regioselective

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

van der Mei, F. W. (2018). Proton-Activated Catalysts for Efficient and Practical Enantioselective Syntheses. (Doctoral Dissertation). Boston College. Retrieved from http://dlib.bc.edu/islandora/object/bc-ir:108140

Chicago Manual of Style (16^th Edition):

van der Mei, Farid Willem. “Proton-Activated Catalysts for Efficient and Practical Enantioselective Syntheses.” 2018. Doctoral Dissertation, Boston College. Accessed April 13, 2021. http://dlib.bc.edu/islandora/object/bc-ir:108140.

MLA Handbook (7^th Edition):

van der Mei, Farid Willem. “Proton-Activated Catalysts for Efficient and Practical Enantioselective Syntheses.” 2018. Web. 13 Apr 2021.

Vancouver:

van der Mei FW. Proton-Activated Catalysts for Efficient and Practical Enantioselective Syntheses. [Internet] [Doctoral dissertation]. Boston College; 2018. [cited 2021 Apr 13]. Available from: http://dlib.bc.edu/islandora/object/bc-ir:108140.

Council of Science Editors:

van der Mei FW. Proton-Activated Catalysts for Efficient and Practical Enantioselective Syntheses. [Doctoral Dissertation]. Boston College; 2018. Available from: http://dlib.bc.edu/islandora/object/bc-ir:108140

University of Alberta

21. Hass, Michael J. Reusable Ru and Rh catalysts for ester hydrogenations and enyne cycloisomerizations.

Degree: MS, Department of Chemistry, 2012, University of Alberta

URL: https://era.library.ualberta.ca/files/n296x015t

► A method was developed to immobilize and reuse a catalyst for the asymmetric cycloisomerization of enynes. Immobilization is achieved through use of metal containing monomers,… (more)

Subjects/Keywords: cycloisomerization; rhodium; catalyst immobilization; catalysis; enantioselective

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APA (6^th Edition):

Hass, M. J. (2012). Reusable Ru and Rh catalysts for ester hydrogenations and enyne cycloisomerizations. (Masters Thesis). University of Alberta. Retrieved from https://era.library.ualberta.ca/files/n296x015t

Chicago Manual of Style (16^th Edition):

Hass, Michael J. “Reusable Ru and Rh catalysts for ester hydrogenations and enyne cycloisomerizations.” 2012. Masters Thesis, University of Alberta. Accessed April 13, 2021. https://era.library.ualberta.ca/files/n296x015t.

MLA Handbook (7^th Edition):

Hass, Michael J. “Reusable Ru and Rh catalysts for ester hydrogenations and enyne cycloisomerizations.” 2012. Web. 13 Apr 2021.

Vancouver:

Hass MJ. Reusable Ru and Rh catalysts for ester hydrogenations and enyne cycloisomerizations. [Internet] [Masters thesis]. University of Alberta; 2012. [cited 2021 Apr 13]. Available from: https://era.library.ualberta.ca/files/n296x015t.

Council of Science Editors:

Hass MJ. Reusable Ru and Rh catalysts for ester hydrogenations and enyne cycloisomerizations. [Masters Thesis]. University of Alberta; 2012. Available from: https://era.library.ualberta.ca/files/n296x015t

University of Alberta

22. Sullivan, Erin Rae. Enantioselective formation of propargylic alcohols.

Degree: PhD, Department of Chemistry, 2011, University of Alberta

URL: https://era.library.ualberta.ca/files/mk61rh89v

► Propargylic alcohol natural products are found in many species of terrestrial plants and marine organisms. Because these compounds are usually isolated from the natural source… (more)

▼ Propargylic alcohol natural products are found in many species of terrestrial plants and marine organisms. Because these compounds are usually isolated from the natural source in only small amounts, few studies of propargylic alcohol natural products have been conducted to date. Nevertheless, these studies show compounds with this backbone have diverse biological activities and potential for pharmaceutical applications. Recently, routes have been developed for the asymmetric addition of monoynes to aldehydes, forming propargylic alcohols in high enantioselectivities. At the commencement of this thesis research, however, little work had been reported toward the asymmetric addition of polyynes to aldehydes. As outlined in Chapter 1, the polyynol functionality is quite prevalent in nature, and therefore efficient synthetic routes to this framework could provide compounds to help improve our understanding of the origin of their diverse biological activities. Chapter 2 addresses the asymmetric addition of terminal di- and triynes to aldehydes along, with a one-pot Fritsch-Buttenberg-Wiechell rearrangement-asymmetric addition reaction. The asymmetric addition of terminal diynes and triynes would be a more direct route to polyynol natural products, avoiding the use of tedious cross-coupling reactions. The one-pot protocol would again be a more expedient route and would circumvent the isolation of an unstable terminal polyyne. A second functional group that has shown wide application in natural product synthesis is the homoallylic propargylic alcohol moiety, as it contains three distinct synthetic handles: the alkyne, alkene and alcohol. The most direct route to a homoallylic propargylic alcohol is to perform an allylation reaction on a propargylic aldehyde. The most frequent allyl transfer method applied in natural product synthesis is an allylation with an allylboron reagent known as an allylboration reaction. Despite the popularity of this framework, no catalytic asymmetric allylboration reaction currently exists for propargylic aldehydes. Current methodologies to homoallylic propargylic alcohols either apply a stoichiometric amount of a chiral allylborane or the use of harsh allyl metal species. Chapter 3 describes the catalytic asymmetric allylboration of propargylic aldehydes.

Subjects/Keywords: Alcohol; Polyyne; Enantioselective; natural product; Propargylic

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APA (6^th Edition):

Sullivan, E. R. (2011). Enantioselective formation of propargylic alcohols. (Doctoral Dissertation). University of Alberta. Retrieved from https://era.library.ualberta.ca/files/mk61rh89v

Chicago Manual of Style (16^th Edition):

Sullivan, Erin Rae. “Enantioselective formation of propargylic alcohols.” 2011. Doctoral Dissertation, University of Alberta. Accessed April 13, 2021. https://era.library.ualberta.ca/files/mk61rh89v.

MLA Handbook (7^th Edition):

Sullivan, Erin Rae. “Enantioselective formation of propargylic alcohols.” 2011. Web. 13 Apr 2021.

Vancouver:

Sullivan ER. Enantioselective formation of propargylic alcohols. [Internet] [Doctoral dissertation]. University of Alberta; 2011. [cited 2021 Apr 13]. Available from: https://era.library.ualberta.ca/files/mk61rh89v.

Council of Science Editors:

Sullivan ER. Enantioselective formation of propargylic alcohols. [Doctoral Dissertation]. University of Alberta; 2011. Available from: https://era.library.ualberta.ca/files/mk61rh89v

University of Utah

23. Werner, Erik Winters. Development and evaluation of reactions utilizing uniquely selective electrophilic Pd catalysts.

Degree: PhD, Chemistry, 2012, University of Utah

URL: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/1939/rec/684

► The Heck reaction is an important tool in target-directed syntheses, but its fullpotential has yet to be realized due to limited substrate compatibility. This limitationarises… (more)

▼ The Heck reaction is an important tool in target-directed syntheses, but its fullpotential has yet to be realized due to limited substrate compatibility. This limitationarises from poor behavior of the selectivity-determining steps of migratory insertion and -hydride elimination when using electronically nonbiased substrates. The inability toaccommodate nonbiased alkenes is due to chemist's poor understanding of thecontrolling factors in these two key mechanistic steps. Herein are described Pd0 and PdIIcatalysts that exhibit unique selectivity in these electronically nonbiased molecularsystems.Chapter 1 describes the use of an electrophilic PdII catalyst to install two identicalaryl groups upon terminal aliphatic olefins. The use of the same system, with a differentaryl source, led to the discovery that electrophilic PdII catalysts are capable of selectivelydelivering (E)-styrenyl products from electronically nonbiased olefins.Chapter 2 details optimization of the PdII system to selectively delivertraditionally inaccessible (E)-styrenyl products, and evaluation of substrate scope.Mechanistic experiments are performed, suggesting that the unique selectivity observedis attributable to the cationic nature of the catalyst, that the ligand on Pd is required forcatalyst stability, and that the catalyst distinguishes between B-hydrogens on the basis ofC-H bond strength. These findings are applied to rational design of a Pd0-catalyzedHeck reaction of similar substrates.The Pd0-catalyzed system exhibits greater functional group tolerance than theoxidative system, is operationally simple, and requires no added stabilizing ligand. Thedesign and study of this reaction is the subject of Chapter 3. Mechanistic studies suggestthat solvent choice is crucial in allowing the metal center to distinguish between -hydrogens on the basis of their relative hydridic nature.The insight gained in the work described in Chapters 2 and 3 allowed for therational design of a system enabling enantioselective Heck reactions using acyclicsubstrates. This methodology, described in Chapter 4, was intended to deliver opticallyactive -aryl ketones from allylic alcohol substrates. After establishing that the reactionperforms as anticipated, it was applied to the unprecedented single-step enantioselectivesynthesis of y-aryl ketones, and aldehydes, and a d-aryl aldehyde.

Subjects/Keywords: Catalysis; Enantioselective; Heck; Palladium; Selective; Styrene

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APA (6^th Edition):

Werner, E. W. (2012). Development and evaluation of reactions utilizing uniquely selective electrophilic Pd catalysts. (Doctoral Dissertation). University of Utah. Retrieved from http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/1939/rec/684

Chicago Manual of Style (16^th Edition):

Werner, Erik Winters. “Development and evaluation of reactions utilizing uniquely selective electrophilic Pd catalysts.” 2012. Doctoral Dissertation, University of Utah. Accessed April 13, 2021. http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/1939/rec/684.

MLA Handbook (7^th Edition):

Werner, Erik Winters. “Development and evaluation of reactions utilizing uniquely selective electrophilic Pd catalysts.” 2012. Web. 13 Apr 2021.

Vancouver:

Werner EW. Development and evaluation of reactions utilizing uniquely selective electrophilic Pd catalysts. [Internet] [Doctoral dissertation]. University of Utah; 2012. [cited 2021 Apr 13]. Available from: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/1939/rec/684.

Council of Science Editors:

Werner EW. Development and evaluation of reactions utilizing uniquely selective electrophilic Pd catalysts. [Doctoral Dissertation]. University of Utah; 2012. Available from: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/1939/rec/684

Texas A&M University

24. Lewis, Kyle. The Development of Werner-type Cobalt Complexes in Enantioselective Hydrogen Bond Mediated Catalysis.

Degree: PhD, Chemistry, 2013, Texas A&M University

URL: http://hdl.handle.net/1969.1/151842

► Chiral-at-metal Werner complexes of the type (Λ/∆)-[Co(1,2-diamine)_(3)]^(3+) 3X^(–)have long been a cornerstone of coordination chemistry. However, despite being inexpensive and readily available in enantiopure form,… (more)

▼ Chiral-at-metal Werner complexes of the type (Λ/∆)-[Co(1,2-diamine)_(3)]^(3+) 3X^(–)have long been a cornerstone of coordination chemistry. However, despite being inexpensive and readily available in enantiopure form, they have had no applications in enantioselective organic synthesis. This derives from their poor solubility in organic solvents and the fact that the chelating ligands are non-labile, preventing metal based substrate activation. However, it was conceived that the abundant nitrogen-hydrogen bonds of the diamine ligands could activate Lewis basic substrates towards nucleophilic addition via hydrogen bonding. Towards this end, the diastereomeric trications Λ-[Co((S,S)-dpen)_(3)]^(3+) and ∆-[Co((S,S)-dpen)_(3)]^(3+) (dpen = diphenyl ethylenediamine) were prepared by stereoselective syntheses. Incorporation of the lipophilic Bar_(f)^(–) (B(3,5-CF_(3)-C_(6)H_(3))_(4)^(–)) anion, among others, afforded the organic-soluble mixed salts Λ-[Co((S,S)-dpen)_(3)]^(3+) 2X^(–) BAr_(f)^(-) and ∆-[Co((S,S)-dpen)_(3)]^(3+) 2X^(–) Bar^( –)(X = Cl^(–), BF_(4)^(–), PF_(6)^(–)). These Werner complexes were then applied as hydrogen bond mediating catalysts for enantioselective Michael additions of dialkyl malonates to nitroolefins. The catalyzed Michael addition of dimethyl malonate (15a) to trans-β- nitrostyrene was optimized with respect to solvent, temperature, and catalyst counteranion and then extended to a range of nitroolefin substrates. Under optimized – conditions, Λ-(S,S)-3^(3+) 2BF_(4)^(–) Bar_(f)^(-) (10 mol%) catalyzes the Michael addition of 15a to 2-benzyloxy-trans-β-nitrostyrene in acetone at 0 °C in the presence of Et_(3)N (1.0 equiv) to afford dimethyl 2-(2-nitro-1-(2 benzyloxyphenyl)ethyl)malonate in 95% isolated yield and 96% ee. This work marks the first time that a Werner-type complex has been applied as a catalyst for organic transformations with high enantioselectivities. The unique stereochemistry of the Werner complex, which features a chiral metal center, is primarily responsible for the stereoselectivity of the catalyzed reactions. Advisors/Committee Members: Gladysz, John A (advisor), Darensbourg, Don (committee member), Wooley, Karen (committee member), Schwab, Arthur P (committee member).

Subjects/Keywords: Werner complex; hydrogen bonding; enantioselective; catalysis

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Lewis, K. (2013). The Development of Werner-type Cobalt Complexes in Enantioselective Hydrogen Bond Mediated Catalysis. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/151842

Chicago Manual of Style (16^th Edition):

Lewis, Kyle. “The Development of Werner-type Cobalt Complexes in Enantioselective Hydrogen Bond Mediated Catalysis.” 2013. Doctoral Dissertation, Texas A&M University. Accessed April 13, 2021. http://hdl.handle.net/1969.1/151842.

MLA Handbook (7^th Edition):

Lewis, Kyle. “The Development of Werner-type Cobalt Complexes in Enantioselective Hydrogen Bond Mediated Catalysis.” 2013. Web. 13 Apr 2021.

Vancouver:

Lewis K. The Development of Werner-type Cobalt Complexes in Enantioselective Hydrogen Bond Mediated Catalysis. [Internet] [Doctoral dissertation]. Texas A&M University; 2013. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/1969.1/151842.

Council of Science Editors:

Lewis K. The Development of Werner-type Cobalt Complexes in Enantioselective Hydrogen Bond Mediated Catalysis. [Doctoral Dissertation]. Texas A&M University; 2013. Available from: http://hdl.handle.net/1969.1/151842

Brigham Young University

25. Walker, Whitney Kaye. Electrophilic Catalysis Using Heterobimetallic Complexes.

Degree: PhD, 2017, Brigham Young University

URL: https://scholarsarchive.byu.edu/cgi/viewcontent.cgi?article=7962&context=etd

► Conventional ligand design in transition metal catalysis capitalizes on the ability of phosphorous, nitrogen, carbon, oxygen, and sulfur-based donors to modify the steric and electronic… (more)

▼ Conventional ligand design in transition metal catalysis capitalizes on the ability of phosphorous, nitrogen, carbon, oxygen, and sulfur-based donors to modify the steric and electronic properties of a reactive metal center. Heterobimetallic transition metal complexes that contain a dative metal-metal bond provide a unique approach to ligand design where the reactivity of the metal center can be modified by metal-metal electronic communication. Our laboratory is interested in using the unique properties of heterobimetallic complexes to address significant limitations in current transition metal catalysis. My PhD work has focused on the ability of early/late transition metal heterobimetallic complexes to facilitate catalysis by speeding up reductive processes that occur at the late transition metal center. My initial studies were aimed at understanding the importance of the metal-metal interaction to catalysis in allylic amination reactions catalyzed by Pd–Ti heterobimetallic complexes and the potential of these catalysts to enable reactivity with challenging nitrogen nucleophiles. We also explored the substrate scope of the allylic amination with a variety of hindered amines and allylic chloride substrates under mild conditions. Aminations of this type have previously been shown to require harsh reaction conditions and tend to give low yields. A variety of sterically hindered secondary amine nucleophiles were able to readily undergo allylic substitution. Many of these aminations were complete within ten minutes. A series of allylic electrophiles were also shown to undergo the reaction. We have also looked at the ability of hindered amines to undergo intramolecular cyclizations to produce pyrrolidine and piperidine products. My continuing efforts in the laboratory are focused on developing chiral titanium-phosphinoamide ligands for enantioselective heterobimetallic catalysis. We have synthesized a series of chiral diamine-based phosphinoamide-titanium ligands in order to investigate enantioselective intramolecular aminations. Importantly, each of these new Ti-ligands enables room temperature catalysis in intramolecular aminations with hindered amines, suggesting contributions by the Ti center. Similar reactivity has not been achieved with monometallic chiral Pd catalysts in our lab. Importantly, many of these ligands enable modest enantioselectivity in the allylic aminations.

Subjects/Keywords: heterobimetallic; catalysis; allylic aminations; enantioselective; Chemistry

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APA (6^th Edition):

Walker, W. K. (2017). Electrophilic Catalysis Using Heterobimetallic Complexes. (Doctoral Dissertation). Brigham Young University. Retrieved from https://scholarsarchive.byu.edu/cgi/viewcontent.cgi?article=7962&context=etd

Chicago Manual of Style (16^th Edition):

Walker, Whitney Kaye. “Electrophilic Catalysis Using Heterobimetallic Complexes.” 2017. Doctoral Dissertation, Brigham Young University. Accessed April 13, 2021. https://scholarsarchive.byu.edu/cgi/viewcontent.cgi?article=7962&context=etd.

MLA Handbook (7^th Edition):

Walker, Whitney Kaye. “Electrophilic Catalysis Using Heterobimetallic Complexes.” 2017. Web. 13 Apr 2021.

Vancouver:

Walker WK. Electrophilic Catalysis Using Heterobimetallic Complexes. [Internet] [Doctoral dissertation]. Brigham Young University; 2017. [cited 2021 Apr 13]. Available from: https://scholarsarchive.byu.edu/cgi/viewcontent.cgi?article=7962&context=etd.

Council of Science Editors:

Walker WK. Electrophilic Catalysis Using Heterobimetallic Complexes. [Doctoral Dissertation]. Brigham Young University; 2017. Available from: https://scholarsarchive.byu.edu/cgi/viewcontent.cgi?article=7962&context=etd

Colorado State University

26. Dalton, Derek M. Mechanistic investigations and ligand development for rhodium catalyzed [2+2+2] and zinc catalyzed [4+2] cycloadditions.

Degree: PhD, Chemistry, 2013, Colorado State University

URL: http://hdl.handle.net/10217/80142

► Described herein are mechanistic studies and ligand development for Rh(I) catalyzed [2+2+2] cycloaddition reactions of alkene tethered isocyanates and exogenous alkynes. A mechanistic hypothesis has… (more)

Subjects/Keywords: cycloaddition; zinc; rhodium; enantioselective; heterocycles; catalysis

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APA (6^th Edition):

Dalton, D. M. (2013). Mechanistic investigations and ligand development for rhodium catalyzed [2+2+2] and zinc catalyzed [4+2] cycloadditions. (Doctoral Dissertation). Colorado State University. Retrieved from http://hdl.handle.net/10217/80142

Chicago Manual of Style (16^th Edition):

Dalton, Derek M. “Mechanistic investigations and ligand development for rhodium catalyzed [2+2+2] and zinc catalyzed [4+2] cycloadditions.” 2013. Doctoral Dissertation, Colorado State University. Accessed April 13, 2021. http://hdl.handle.net/10217/80142.

MLA Handbook (7^th Edition):

Dalton, Derek M. “Mechanistic investigations and ligand development for rhodium catalyzed [2+2+2] and zinc catalyzed [4+2] cycloadditions.” 2013. Web. 13 Apr 2021.

Vancouver:

Dalton DM. Mechanistic investigations and ligand development for rhodium catalyzed [2+2+2] and zinc catalyzed [4+2] cycloadditions. [Internet] [Doctoral dissertation]. Colorado State University; 2013. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/10217/80142.

Council of Science Editors:

Dalton DM. Mechanistic investigations and ligand development for rhodium catalyzed [2+2+2] and zinc catalyzed [4+2] cycloadditions. [Doctoral Dissertation]. Colorado State University; 2013. Available from: http://hdl.handle.net/10217/80142

Boston College

27. Edelstein, Emma Kate. Enantioselective synthesis and stereospecific transformations of organoboronic esters.

Degree: PhD, Chemistry, 2018, Boston College

URL: http://dlib.bc.edu/islandora/object/bc-ir:108038

► This dissertation details the development of several enantioselective or stereospecific transformations involving organoboronic esters. Chapter one will introduce electrophile-induced boronate rearrangements which underpins much of… (more)

Subjects/Keywords: Boron; Catalysis; Cross-Coupling; Enantioselective; Palladium; Stereospecific

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APA (6^th Edition):

Edelstein, E. K. (2018). Enantioselective synthesis and stereospecific transformations of organoboronic esters. (Doctoral Dissertation). Boston College. Retrieved from http://dlib.bc.edu/islandora/object/bc-ir:108038

Chicago Manual of Style (16^th Edition):

Edelstein, Emma Kate. “Enantioselective synthesis and stereospecific transformations of organoboronic esters.” 2018. Doctoral Dissertation, Boston College. Accessed April 13, 2021. http://dlib.bc.edu/islandora/object/bc-ir:108038.

MLA Handbook (7^th Edition):

Edelstein, Emma Kate. “Enantioselective synthesis and stereospecific transformations of organoboronic esters.” 2018. Web. 13 Apr 2021.

Vancouver:

Edelstein EK. Enantioselective synthesis and stereospecific transformations of organoboronic esters. [Internet] [Doctoral dissertation]. Boston College; 2018. [cited 2021 Apr 13]. Available from: http://dlib.bc.edu/islandora/object/bc-ir:108038.

Council of Science Editors:

Edelstein EK. Enantioselective synthesis and stereospecific transformations of organoboronic esters. [Doctoral Dissertation]. Boston College; 2018. Available from: http://dlib.bc.edu/islandora/object/bc-ir:108038

Boston College

28. Wen, Fengqi. Catalytic Enantioselective Tosylation of Meso-Alcohols with an Amino-Acid-Based Small Molecule.

Degree: MS, Chemistry, 2011, Boston College

URL: http://dlib.bc.edu/islandora/object/bc-ir:101846

Chapter 1 Review of methodology developments in the area of selective tosylation of alcohols. Chapter 2 Development of a catalytic enantioselective tosylation of alcohols with an amino-acid-based organocatalyst. Advisors/Committee Members: Marc L. Snapper (Thesis advisor).

Subjects/Keywords: Catalytic; Enantioselective; Meso-Alcohols; Small Molecule; Tosylation

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APA (6^th Edition):

Wen, F. (2011). Catalytic Enantioselective Tosylation of Meso-Alcohols with an Amino-Acid-Based Small Molecule. (Masters Thesis). Boston College. Retrieved from http://dlib.bc.edu/islandora/object/bc-ir:101846

Chicago Manual of Style (16^th Edition):

Wen, Fengqi. “Catalytic Enantioselective Tosylation of Meso-Alcohols with an Amino-Acid-Based Small Molecule.” 2011. Masters Thesis, Boston College. Accessed April 13, 2021. http://dlib.bc.edu/islandora/object/bc-ir:101846.

MLA Handbook (7^th Edition):

Wen, Fengqi. “Catalytic Enantioselective Tosylation of Meso-Alcohols with an Amino-Acid-Based Small Molecule.” 2011. Web. 13 Apr 2021.

Vancouver:

Wen F. Catalytic Enantioselective Tosylation of Meso-Alcohols with an Amino-Acid-Based Small Molecule. [Internet] [Masters thesis]. Boston College; 2011. [cited 2021 Apr 13]. Available from: http://dlib.bc.edu/islandora/object/bc-ir:101846.

Council of Science Editors:

Wen F. Catalytic Enantioselective Tosylation of Meso-Alcohols with an Amino-Acid-Based Small Molecule. [Masters Thesis]. Boston College; 2011. Available from: http://dlib.bc.edu/islandora/object/bc-ir:101846

Boston College

29. Eno, Meredith Suzanne. Development of Metal-Catalyzed Asymmetric Carbon-Carbon Bond Forming Reactions.

Degree: PhD, Chemistry, 2017, Boston College

URL: http://dlib.bc.edu/islandora/object/bc-ir:107422

► This dissertation describes the development of four metal-catalyzed carbon-carbon bond forming methods. The first project presented is a palladium-catalyzed proparyl-allyl cross-coupling which proceeds via a… (more)

Subjects/Keywords: catalysis; desymmetrization; diastereoselective; enantioselective; hydroformylation; metal

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APA (6^th Edition):

Eno, M. S. (2017). Development of Metal-Catalyzed Asymmetric Carbon-Carbon Bond Forming Reactions. (Doctoral Dissertation). Boston College. Retrieved from http://dlib.bc.edu/islandora/object/bc-ir:107422

Chicago Manual of Style (16^th Edition):

Eno, Meredith Suzanne. “Development of Metal-Catalyzed Asymmetric Carbon-Carbon Bond Forming Reactions.” 2017. Doctoral Dissertation, Boston College. Accessed April 13, 2021. http://dlib.bc.edu/islandora/object/bc-ir:107422.

MLA Handbook (7^th Edition):

Eno, Meredith Suzanne. “Development of Metal-Catalyzed Asymmetric Carbon-Carbon Bond Forming Reactions.” 2017. Web. 13 Apr 2021.

Vancouver:

Eno MS. Development of Metal-Catalyzed Asymmetric Carbon-Carbon Bond Forming Reactions. [Internet] [Doctoral dissertation]. Boston College; 2017. [cited 2021 Apr 13]. Available from: http://dlib.bc.edu/islandora/object/bc-ir:107422.

Council of Science Editors:

Eno MS. Development of Metal-Catalyzed Asymmetric Carbon-Carbon Bond Forming Reactions. [Doctoral Dissertation]. Boston College; 2017. Available from: http://dlib.bc.edu/islandora/object/bc-ir:107422

Boston College

30. Szymaniak, Adam Anthony. Nonracemic Organoboronates by Transition Metal-Catalyzed C-C and C-Si Bond Forming Reactions.

Degree: PhD, Chemistry, 2018, Boston College

URL: http://dlib.bc.edu/islandora/object/bc-ir:108119

► This dissertation will describe the development of three transition metal-catalyzed syntheses of nonracemic organoboronates. The first chapter explains the development of a palladium-catalyzed enantiotopic-group-selective cross-coupling… (more)

Subjects/Keywords: catalysis; enantioselective; nonracemic; organoboronates; palladium; platinum

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APA (6^th Edition):

Szymaniak, A. A. (2018). Nonracemic Organoboronates by Transition Metal-Catalyzed C-C and C-Si Bond Forming Reactions. (Doctoral Dissertation). Boston College. Retrieved from http://dlib.bc.edu/islandora/object/bc-ir:108119

Chicago Manual of Style (16^th Edition):

Szymaniak, Adam Anthony. “Nonracemic Organoboronates by Transition Metal-Catalyzed C-C and C-Si Bond Forming Reactions.” 2018. Doctoral Dissertation, Boston College. Accessed April 13, 2021. http://dlib.bc.edu/islandora/object/bc-ir:108119.

MLA Handbook (7^th Edition):

Szymaniak, Adam Anthony. “Nonracemic Organoboronates by Transition Metal-Catalyzed C-C and C-Si Bond Forming Reactions.” 2018. Web. 13 Apr 2021.

Vancouver:

Szymaniak AA. Nonracemic Organoboronates by Transition Metal-Catalyzed C-C and C-Si Bond Forming Reactions. [Internet] [Doctoral dissertation]. Boston College; 2018. [cited 2021 Apr 13]. Available from: http://dlib.bc.edu/islandora/object/bc-ir:108119.

Council of Science Editors:

Szymaniak AA. Nonracemic Organoboronates by Transition Metal-Catalyzed C-C and C-Si Bond Forming Reactions. [Doctoral Dissertation]. Boston College; 2018. Available from: http://dlib.bc.edu/islandora/object/bc-ir:108119

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