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Daniel R Fandrick - One of the best experts on this subject based on the ideXlab platform.
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A Computational Investigation of the Ligand-Controlled Cu-Catalyzed Site-Selective Propargylation and Allenylation of Carbonyl Compounds
Organic Letters, 2017Co-Authors: Osvaldo Gutierrez, Daniel R Fandrick, Keith R Fandrick, C. Avery Sader, Nitinchandra D. Patel, Carl A. Busacca, Marisa C. Kozlowski, Chris H. SenanayakeAbstract:A copper-catalyzed site-selective Propargylation/allenylation reaction toward carbonyl compounds has been mechanistically investigated using a computational approach. Different reaction pathways and catalytic cycles were investigated. Control of the site selectivity arises from a destabilizing interaction introduced by the phenyl-substituted ligand.
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Copper-Catalyzed Asymmetric Propargylation of Cyclic Aldimines
Organic Letters, 2016Co-Authors: Daniel R Fandrick, Keith R Fandrick, Christine A. Hart, Ifeanyi S. Okafor, Michael A. Mercadante, Sanjit Sanyal, James T. Masters, Max Sarvestani, Jennifer L. Stockdill, Nelu GrinbergAbstract:The copper-catalyzed asymmetric Propargylation of cyclic aldimines is reported. The influence of the imine trimer to inhibit the reaction was identified, and equilibrium constants between the monomer and trimer were determined for general classes of imines. Asymmetric Propargylation of a diverse series of N-alkyl and N-aryl aldimines was achieved with good to high asymmetric induction. The utility was demonstrated by a titanium catalyzed hydroamination and reduction to generate the chiral indolizidines (−)-crispine A and (−)-harmicine.
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zinc catalyzed and mediated asymmetric Propargylation of trifluoromethyl ketones with a propargyl boronate
Journal of Organic Chemistry, 2013Co-Authors: Daniel R Fandrick, Jonathan T Reeves, Johanna M Bakonyi, Prasanth R Nyalapatla, Oliver Niemeier, Deniz Akalay, Keith R Fandrick, Wolfgang Wohlleben, Swetlana Ollenberger, Jinhua J SongAbstract:The development of zinc-mediated and -catalyzed asymmetric Propargylations of trifluoromethyl ketones with a propargyl borolane and the N-isopropyl-l-proline ligand is presented. The methodology provided moderate to high stereoselectivity and was successfully applied on a multikilogram scale for the synthesis of the Glucocorticoid agonist BI 653048. A mechanism for the boron–zinc exchange with a propargyl borolane is proposed and supported by modeling at the density functional level of theory. A water acceleration effect on the zinc-catalyzed Propargylation was discovered, which enabled a catalytic process to be achieved. Reaction progress analysis supports a predominately rate limiting exchange for the zinc-catalyzed Propargylation. A catalytic amount of water is proposed to generate an intermediate that catalyzes the exchange, thereby facilitating the reaction with trifluoromethyl ketones.
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a general copper binap catalyzed asymmetric Propargylation of ketones with propargyl boronates
Journal of the American Chemical Society, 2011Co-Authors: Keith R Fandrick, Daniel R Fandrick, Jonathan T Reeves, Nelu Grinberg, Wenjie Li, Bruce Z Lu, Chris H. SenanayakeAbstract:An operationally simple copper–BINAP-catalyzed, highly enantioselective Propargylation of ketones is presented. The methodology was developed as an enantioselective process for methyl ethyl ketone and shown to be applicable to a wide variety of prochiral ketones. The resulting homopropargyl adducts are versatile latent carbonyls from which γ-butyrolactones, β-hydroxy methyl ketones, and β-hydroxycarboxylates are readily obtained.
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A General Copper–BINAP-Catalyzed Asymmetric Propargylation of Ketones with Propargyl Boronates
Journal of the American Chemical Society, 2011Co-Authors: Keith R Fandrick, Daniel R Fandrick, Jonathan T Reeves, Nelu Grinberg, Wenjie Li, Bruce Z Lu, Shengli Ma, Chris H. SenanayakeAbstract:An operationally simple copper–BINAP-catalyzed, highly enantioselective Propargylation of ketones is presented. The methodology was developed as an enantioselective process for methyl ethyl ketone and shown to be applicable to a wide variety of prochiral ketones. The resulting homopropargyl adducts are versatile latent carbonyls from which γ-butyrolactones, β-hydroxy methyl ketones, and β-hydroxycarboxylates are readily obtained.
Chris H. Senanayake - One of the best experts on this subject based on the ideXlab platform.
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A Computational Investigation of the Ligand-Controlled Cu-Catalyzed Site-Selective Propargylation and Allenylation of Carbonyl Compounds
Organic Letters, 2017Co-Authors: Osvaldo Gutierrez, Daniel R Fandrick, Keith R Fandrick, C. Avery Sader, Nitinchandra D. Patel, Carl A. Busacca, Marisa C. Kozlowski, Chris H. SenanayakeAbstract:A copper-catalyzed site-selective Propargylation/allenylation reaction toward carbonyl compounds has been mechanistically investigated using a computational approach. Different reaction pathways and catalytic cycles were investigated. Control of the site selectivity arises from a destabilizing interaction introduced by the phenyl-substituted ligand.
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a general copper binap catalyzed asymmetric Propargylation of ketones with propargyl boronates
Journal of the American Chemical Society, 2011Co-Authors: Keith R Fandrick, Daniel R Fandrick, Jonathan T Reeves, Nelu Grinberg, Wenjie Li, Bruce Z Lu, Chris H. SenanayakeAbstract:An operationally simple copper–BINAP-catalyzed, highly enantioselective Propargylation of ketones is presented. The methodology was developed as an enantioselective process for methyl ethyl ketone and shown to be applicable to a wide variety of prochiral ketones. The resulting homopropargyl adducts are versatile latent carbonyls from which γ-butyrolactones, β-hydroxy methyl ketones, and β-hydroxycarboxylates are readily obtained.
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A General Copper–BINAP-Catalyzed Asymmetric Propargylation of Ketones with Propargyl Boronates
Journal of the American Chemical Society, 2011Co-Authors: Keith R Fandrick, Daniel R Fandrick, Jonathan T Reeves, Nelu Grinberg, Wenjie Li, Bruce Z Lu, Shengli Ma, Chris H. SenanayakeAbstract:An operationally simple copper–BINAP-catalyzed, highly enantioselective Propargylation of ketones is presented. The methodology was developed as an enantioselective process for methyl ethyl ketone and shown to be applicable to a wide variety of prochiral ketones. The resulting homopropargyl adducts are versatile latent carbonyls from which γ-butyrolactones, β-hydroxy methyl ketones, and β-hydroxycarboxylates are readily obtained.
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copper catalyzed asymmetric Propargylation of aldehydes
Journal of the American Chemical Society, 2010Co-Authors: Daniel R Fandrick, Jonathan T Reeves, Keith R Fandrick, Jinhua J Song, Wenjun Tang, Andrew G Capacci, Sonia Rodriguez, Chris H. SenanayakeAbstract:The highly enantio- and regioselective copper catalyzed asymmetric Propargylation of aldehydes with a propargyl borolane reagent is reported. The methodology demonstrated broad functional group tolerance and provided high enantioselectivities for aliphatic, vinyl, and aryl aldehydes. The utility of the TMS homopropargylic alcohols was demonstrated by the facile conversion to a chiral dihydropyranone.
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highly diastereoselective zinc catalyzed Propargylation of tert butanesulfinyl imines
Organic Letters, 2010Co-Authors: Daniel R Fandrick, Jonathan T Reeves, Keith R Fandrick, Jinhua J Song, Courtney S. Johnson, Chris H. SenanayakeAbstract:A zinc-catalyzed diastereoselective Propargylation of t-butanesulfinyl imines is presented. The methodology provided both aliphatic and aryl homopropargylic amines in up to 98:2 and 99.8:0.2 dr, respectively. The utility of the homopropargylic amines was demonstrated by the application to the synthesis of a cis-substituted pyrido-indole through a diastereoselective Pictet−Spengler cyclization.
Jinhua J Song - One of the best experts on this subject based on the ideXlab platform.
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zinc catalyzed and mediated asymmetric Propargylation of trifluoromethyl ketones with a propargyl boronate
Journal of Organic Chemistry, 2013Co-Authors: Daniel R Fandrick, Jonathan T Reeves, Johanna M Bakonyi, Prasanth R Nyalapatla, Oliver Niemeier, Deniz Akalay, Keith R Fandrick, Wolfgang Wohlleben, Swetlana Ollenberger, Jinhua J SongAbstract:The development of zinc-mediated and -catalyzed asymmetric Propargylations of trifluoromethyl ketones with a propargyl borolane and the N-isopropyl-l-proline ligand is presented. The methodology provided moderate to high stereoselectivity and was successfully applied on a multikilogram scale for the synthesis of the Glucocorticoid agonist BI 653048. A mechanism for the boron–zinc exchange with a propargyl borolane is proposed and supported by modeling at the density functional level of theory. A water acceleration effect on the zinc-catalyzed Propargylation was discovered, which enabled a catalytic process to be achieved. Reaction progress analysis supports a predominately rate limiting exchange for the zinc-catalyzed Propargylation. A catalytic amount of water is proposed to generate an intermediate that catalyzes the exchange, thereby facilitating the reaction with trifluoromethyl ketones.
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copper catalyzed asymmetric Propargylation of aldehydes
Journal of the American Chemical Society, 2010Co-Authors: Daniel R Fandrick, Jonathan T Reeves, Keith R Fandrick, Jinhua J Song, Wenjun Tang, Andrew G Capacci, Sonia Rodriguez, Chris H. SenanayakeAbstract:The highly enantio- and regioselective copper catalyzed asymmetric Propargylation of aldehydes with a propargyl borolane reagent is reported. The methodology demonstrated broad functional group tolerance and provided high enantioselectivities for aliphatic, vinyl, and aryl aldehydes. The utility of the TMS homopropargylic alcohols was demonstrated by the facile conversion to a chiral dihydropyranone.
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highly diastereoselective zinc catalyzed Propargylation of tert butanesulfinyl imines
Organic Letters, 2010Co-Authors: Daniel R Fandrick, Jonathan T Reeves, Keith R Fandrick, Jinhua J Song, Courtney S. Johnson, Chris H. SenanayakeAbstract:A zinc-catalyzed diastereoselective Propargylation of t-butanesulfinyl imines is presented. The methodology provided both aliphatic and aryl homopropargylic amines in up to 98:2 and 99.8:0.2 dr, respectively. The utility of the homopropargylic amines was demonstrated by the application to the synthesis of a cis-substituted pyrido-indole through a diastereoselective Pictet−Spengler cyclization.
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Zinc catalyzed and mediated Propargylations with propargyl boronates.
Organic Letters, 2010Co-Authors: Daniel R Fandrick, Jonathan T Reeves, Keith R Fandrick, Jinhua J Song, Courtney S. Johnson, Chris H. SenanayakeAbstract:The utility of allenyl and propargyl boronates for the Propargylation of aldehydes and ketones mediated by zinc is presented. The reaction is catalytic in zinc with allenyl or propargyl borolanes. The Propargylation with crystalline and air-stable propargyl diethanolamine boronates was also achieved. A catalytic cycle is proposed, and preliminary mechanistic studies are discussed.
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Regioselective allene synthesis and Propargylations with propargyl diethanolamine boronates.
Organic Letters, 2009Co-Authors: Daniel R Fandrick, Jonathan T Reeves, Jinhua J Song, Chris H. SenanayakeAbstract:The utility of propargyl diethanolamine boronates as reagents for the preparation of allenes and homopropargylic alcohols is presented. Protonolysis with TFA and electrophilic substitution with N-halosuccinimides proceeded with inversion to provide the corresponding allene in high yield and regioselectivity. Alternatively, the Propargylation of aldehydes was achieved with use of the in situ generated lithiated complex.
Yoshiaki Nishibayashi - One of the best experts on this subject based on the ideXlab platform.
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construction of chiral tri and tetra arylmethanes bearing quaternary carbon centers copper catalyzed enantioselective Propargylation of indoles with propargylic esters
Angewandte Chemie, 2016Co-Authors: Kouhei Tsuchida, Yasushi Senda, Kazunari Nakajima, Yoshiaki NishibayashiAbstract:Copper-catalyzed enantioselective Propargylation of indoles with propargylic esters and sequential Huisgen cycloaddition with azides lead to the construction of chiral triarylmethanes, bearing a quaternary carbon center, with high to excellent enantioselectivities. The result described herein can be used in the enantioselective preparation of a tetraarylmethane.
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Construction of Chiral Tri‐ and Tetra‐Arylmethanes Bearing Quaternary Carbon Centers: Copper‐Catalyzed Enantioselective Propargylation of Indoles with Propargylic Esters
Angewandte Chemie, 2016Co-Authors: Kouhei Tsuchida, Yasushi Senda, Kazunari Nakajima, Yoshiaki NishibayashiAbstract:Copper-catalyzed enantioselective Propargylation of indoles with propargylic esters and sequential Huisgen cycloaddition with azides lead to the construction of chiral triarylmethanes, bearing a quaternary carbon center, with high to excellent enantioselectivities. The result described herein can be used in the enantioselective preparation of a tetraarylmethane.
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ruthenium catalyzed Propargylation of aromatic compounds with propargylic alcohols
Journal of the American Chemical Society, 2002Co-Authors: Yoshiaki Nishibayashi, Masato Yoshikawa, Youichi Inada, Masanobu Hidai, Sakae UemuraAbstract:A novel ruthenium-catalyzed Propargylation of aromatic compounds with propargylic alcohols has been found to afford the corresponding propargylated aromatic products in good yields with complete regioselectivity. The catalytic reaction provides a potential usefulness for practical application in organic synthesis, because the selective Propargylation of aromatic compounds with an aromatic C−H bond cleavage is generally difficult.
Keith R Fandrick - One of the best experts on this subject based on the ideXlab platform.
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A Computational Investigation of the Ligand-Controlled Cu-Catalyzed Site-Selective Propargylation and Allenylation of Carbonyl Compounds
Organic Letters, 2017Co-Authors: Osvaldo Gutierrez, Daniel R Fandrick, Keith R Fandrick, C. Avery Sader, Nitinchandra D. Patel, Carl A. Busacca, Marisa C. Kozlowski, Chris H. SenanayakeAbstract:A copper-catalyzed site-selective Propargylation/allenylation reaction toward carbonyl compounds has been mechanistically investigated using a computational approach. Different reaction pathways and catalytic cycles were investigated. Control of the site selectivity arises from a destabilizing interaction introduced by the phenyl-substituted ligand.
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Copper-Catalyzed Asymmetric Propargylation of Cyclic Aldimines
Organic Letters, 2016Co-Authors: Daniel R Fandrick, Keith R Fandrick, Christine A. Hart, Ifeanyi S. Okafor, Michael A. Mercadante, Sanjit Sanyal, James T. Masters, Max Sarvestani, Jennifer L. Stockdill, Nelu GrinbergAbstract:The copper-catalyzed asymmetric Propargylation of cyclic aldimines is reported. The influence of the imine trimer to inhibit the reaction was identified, and equilibrium constants between the monomer and trimer were determined for general classes of imines. Asymmetric Propargylation of a diverse series of N-alkyl and N-aryl aldimines was achieved with good to high asymmetric induction. The utility was demonstrated by a titanium catalyzed hydroamination and reduction to generate the chiral indolizidines (−)-crispine A and (−)-harmicine.
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zinc catalyzed and mediated asymmetric Propargylation of trifluoromethyl ketones with a propargyl boronate
Journal of Organic Chemistry, 2013Co-Authors: Daniel R Fandrick, Jonathan T Reeves, Johanna M Bakonyi, Prasanth R Nyalapatla, Oliver Niemeier, Deniz Akalay, Keith R Fandrick, Wolfgang Wohlleben, Swetlana Ollenberger, Jinhua J SongAbstract:The development of zinc-mediated and -catalyzed asymmetric Propargylations of trifluoromethyl ketones with a propargyl borolane and the N-isopropyl-l-proline ligand is presented. The methodology provided moderate to high stereoselectivity and was successfully applied on a multikilogram scale for the synthesis of the Glucocorticoid agonist BI 653048. A mechanism for the boron–zinc exchange with a propargyl borolane is proposed and supported by modeling at the density functional level of theory. A water acceleration effect on the zinc-catalyzed Propargylation was discovered, which enabled a catalytic process to be achieved. Reaction progress analysis supports a predominately rate limiting exchange for the zinc-catalyzed Propargylation. A catalytic amount of water is proposed to generate an intermediate that catalyzes the exchange, thereby facilitating the reaction with trifluoromethyl ketones.
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a general copper binap catalyzed asymmetric Propargylation of ketones with propargyl boronates
Journal of the American Chemical Society, 2011Co-Authors: Keith R Fandrick, Daniel R Fandrick, Jonathan T Reeves, Nelu Grinberg, Wenjie Li, Bruce Z Lu, Chris H. SenanayakeAbstract:An operationally simple copper–BINAP-catalyzed, highly enantioselective Propargylation of ketones is presented. The methodology was developed as an enantioselective process for methyl ethyl ketone and shown to be applicable to a wide variety of prochiral ketones. The resulting homopropargyl adducts are versatile latent carbonyls from which γ-butyrolactones, β-hydroxy methyl ketones, and β-hydroxycarboxylates are readily obtained.
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A General Copper–BINAP-Catalyzed Asymmetric Propargylation of Ketones with Propargyl Boronates
Journal of the American Chemical Society, 2011Co-Authors: Keith R Fandrick, Daniel R Fandrick, Jonathan T Reeves, Nelu Grinberg, Wenjie Li, Bruce Z Lu, Shengli Ma, Chris H. SenanayakeAbstract:An operationally simple copper–BINAP-catalyzed, highly enantioselective Propargylation of ketones is presented. The methodology was developed as an enantioselective process for methyl ethyl ketone and shown to be applicable to a wide variety of prochiral ketones. The resulting homopropargyl adducts are versatile latent carbonyls from which γ-butyrolactones, β-hydroxy methyl ketones, and β-hydroxycarboxylates are readily obtained.