The Experts below are selected from a list of 54 Experts worldwide ranked by ideXlab platform
John C. Gordon - One of the best experts on this subject based on the ideXlab platform.
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Why Does Alkylation of the N–H Functionality within M/NH Bifunctional Noyori-Type Catalysts Lead to Turnover?
Journal of the American Chemical Society, 2017Co-Authors: Pavel A. Dub, Brian L. Scott, John C. GordonAbstract:Molecular metal/NH bifunctional Noyori-type catalysts are remarkable in that they are among the most efficient artificial catalysts developed to date for the Hydrogenation of carbonyl functionalities (loadings up to ∼10-5 mol %). In addition, these catalysts typically exhibit high C═O/C═C chemo- and enantioselectivities. This unique set of properties is traditionally associated with the operation of an unconventional mechanism for homogeneous catalysts in which the chelating ligand plays a key role in facilitating the catalytic reaction and enabling the aforementioned selectivities by delivering/accepting a proton (H+) via its N-H bond cleavage/formation. A recently revised mechanism of the Noyori Hydrogenation reaction (Dub, P. A. et al. J. Am. Chem. Soc. 2014, 136, 3505) suggests that the N-H bond is not cleaved but serves to stabilize the turnover-determining transition states (TDTSs) via strong N-H···O hydrogen-bonding interactions (HBIs). The present paper shows that this is consistent with the largely ignored experimental fact that alkylation of the N-H functionality within M/NH bifunctional Noyori-type catalysts leads to detrimental catalytic activity. The purpose of this work is to demonstrate that decreasing the strength of this HBI, ultimately to the limit of its complete absence, are conditions under which the same alkylation may lead to beneficial catalytic activity.
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Why Does Alkylation of the N–H Functionality within M/NH Bifunctional Noyori-Type Catalysts Lead to Turnover?
2017Co-Authors: Pavel A. Dub, Brian L. Scott, John C. GordonAbstract:Molecular metal/NH bifunctional Noyori-type catalysts are remarkable in that they are among the most efficient artificial catalysts developed to date for the Hydrogenation of carbonyl functionalities (loadings up to ∼10–5 mol %). In addition, these catalysts typically exhibit high CO/CC chemo- and enantioselectivities. This unique set of properties is traditionally associated with the operation of an unconventional mechanism for homogeneous catalysts in which the chelating ligand plays a key role in facilitating the catalytic reaction and enabling the aforementioned selectivities by delivering/accepting a proton (H+) via its N–H bond cleavage/formation. A recently revised mechanism of the Noyori Hydrogenation reaction (Dub, P. A. et al. J. Am. Chem. Soc. 2014, 136, 3505) suggests that the N–H bond is not cleaved but serves to stabilize the turnover-determining transition states (TDTSs) via strong N–H···O hydrogen-bonding interactions (HBIs). The present paper shows that this is consistent with the largely ignored experimental fact that alkylation of the N–H functionality within M/NH bifunctional Noyori-type catalysts leads to detrimental catalytic activity. The purpose of this work is to demonstrate that decreasing the strength of this HBI, ultimately to the limit of its complete absence, are conditions under which the same alkylation may lead to beneficial catalytic activity
Pavel A. Dub - One of the best experts on this subject based on the ideXlab platform.
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Why Does Alkylation of the N–H Functionality within M/NH Bifunctional Noyori-Type Catalysts Lead to Turnover?
Journal of the American Chemical Society, 2017Co-Authors: Pavel A. Dub, Brian L. Scott, John C. GordonAbstract:Molecular metal/NH bifunctional Noyori-type catalysts are remarkable in that they are among the most efficient artificial catalysts developed to date for the Hydrogenation of carbonyl functionalities (loadings up to ∼10-5 mol %). In addition, these catalysts typically exhibit high C═O/C═C chemo- and enantioselectivities. This unique set of properties is traditionally associated with the operation of an unconventional mechanism for homogeneous catalysts in which the chelating ligand plays a key role in facilitating the catalytic reaction and enabling the aforementioned selectivities by delivering/accepting a proton (H+) via its N-H bond cleavage/formation. A recently revised mechanism of the Noyori Hydrogenation reaction (Dub, P. A. et al. J. Am. Chem. Soc. 2014, 136, 3505) suggests that the N-H bond is not cleaved but serves to stabilize the turnover-determining transition states (TDTSs) via strong N-H···O hydrogen-bonding interactions (HBIs). The present paper shows that this is consistent with the largely ignored experimental fact that alkylation of the N-H functionality within M/NH bifunctional Noyori-type catalysts leads to detrimental catalytic activity. The purpose of this work is to demonstrate that decreasing the strength of this HBI, ultimately to the limit of its complete absence, are conditions under which the same alkylation may lead to beneficial catalytic activity.
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Why Does Alkylation of the N–H Functionality within M/NH Bifunctional Noyori-Type Catalysts Lead to Turnover?
2017Co-Authors: Pavel A. Dub, Brian L. Scott, John C. GordonAbstract:Molecular metal/NH bifunctional Noyori-type catalysts are remarkable in that they are among the most efficient artificial catalysts developed to date for the Hydrogenation of carbonyl functionalities (loadings up to ∼10–5 mol %). In addition, these catalysts typically exhibit high CO/CC chemo- and enantioselectivities. This unique set of properties is traditionally associated with the operation of an unconventional mechanism for homogeneous catalysts in which the chelating ligand plays a key role in facilitating the catalytic reaction and enabling the aforementioned selectivities by delivering/accepting a proton (H+) via its N–H bond cleavage/formation. A recently revised mechanism of the Noyori Hydrogenation reaction (Dub, P. A. et al. J. Am. Chem. Soc. 2014, 136, 3505) suggests that the N–H bond is not cleaved but serves to stabilize the turnover-determining transition states (TDTSs) via strong N–H···O hydrogen-bonding interactions (HBIs). The present paper shows that this is consistent with the largely ignored experimental fact that alkylation of the N–H functionality within M/NH bifunctional Noyori-type catalysts leads to detrimental catalytic activity. The purpose of this work is to demonstrate that decreasing the strength of this HBI, ultimately to the limit of its complete absence, are conditions under which the same alkylation may lead to beneficial catalytic activity
Brian L. Scott - One of the best experts on this subject based on the ideXlab platform.
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Why Does Alkylation of the N–H Functionality within M/NH Bifunctional Noyori-Type Catalysts Lead to Turnover?
Journal of the American Chemical Society, 2017Co-Authors: Pavel A. Dub, Brian L. Scott, John C. GordonAbstract:Molecular metal/NH bifunctional Noyori-type catalysts are remarkable in that they are among the most efficient artificial catalysts developed to date for the Hydrogenation of carbonyl functionalities (loadings up to ∼10-5 mol %). In addition, these catalysts typically exhibit high C═O/C═C chemo- and enantioselectivities. This unique set of properties is traditionally associated with the operation of an unconventional mechanism for homogeneous catalysts in which the chelating ligand plays a key role in facilitating the catalytic reaction and enabling the aforementioned selectivities by delivering/accepting a proton (H+) via its N-H bond cleavage/formation. A recently revised mechanism of the Noyori Hydrogenation reaction (Dub, P. A. et al. J. Am. Chem. Soc. 2014, 136, 3505) suggests that the N-H bond is not cleaved but serves to stabilize the turnover-determining transition states (TDTSs) via strong N-H···O hydrogen-bonding interactions (HBIs). The present paper shows that this is consistent with the largely ignored experimental fact that alkylation of the N-H functionality within M/NH bifunctional Noyori-type catalysts leads to detrimental catalytic activity. The purpose of this work is to demonstrate that decreasing the strength of this HBI, ultimately to the limit of its complete absence, are conditions under which the same alkylation may lead to beneficial catalytic activity.
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Why Does Alkylation of the N–H Functionality within M/NH Bifunctional Noyori-Type Catalysts Lead to Turnover?
2017Co-Authors: Pavel A. Dub, Brian L. Scott, John C. GordonAbstract:Molecular metal/NH bifunctional Noyori-type catalysts are remarkable in that they are among the most efficient artificial catalysts developed to date for the Hydrogenation of carbonyl functionalities (loadings up to ∼10–5 mol %). In addition, these catalysts typically exhibit high CO/CC chemo- and enantioselectivities. This unique set of properties is traditionally associated with the operation of an unconventional mechanism for homogeneous catalysts in which the chelating ligand plays a key role in facilitating the catalytic reaction and enabling the aforementioned selectivities by delivering/accepting a proton (H+) via its N–H bond cleavage/formation. A recently revised mechanism of the Noyori Hydrogenation reaction (Dub, P. A. et al. J. Am. Chem. Soc. 2014, 136, 3505) suggests that the N–H bond is not cleaved but serves to stabilize the turnover-determining transition states (TDTSs) via strong N–H···O hydrogen-bonding interactions (HBIs). The present paper shows that this is consistent with the largely ignored experimental fact that alkylation of the N–H functionality within M/NH bifunctional Noyori-type catalysts leads to detrimental catalytic activity. The purpose of this work is to demonstrate that decreasing the strength of this HBI, ultimately to the limit of its complete absence, are conditions under which the same alkylation may lead to beneficial catalytic activity
Gunda I Georg - One of the best experts on this subject based on the ideXlab platform.
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practical syntheses of the c12 c21 epothilone subunit via catalytic asymmetric reductions itsuno corey oxazaborolidine reduction and asymmetric Noyori Hydrogenation
Tetrahedron Letters, 2004Co-Authors: Emily A Reiff, Sajiv K Nair, B Narayan S Reddy, Jun Inagaki, John T Henri, Jack F Greiner, Gunda I GeorgAbstract:Abstract Two practical catalytic asymmetric reductions to introduce the epothilone C15 stereocenter are described (Itsuno–Corey reduction and Noyori Hydrogenation).
Victor Polo - One of the best experts on this subject based on the ideXlab platform.
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a bonding evolution theory study on the catalytic Noyori Hydrogenation reaction
Molecular Physics, 2019Co-Authors: Julen Munarriz, Ruben Laplaza, Victor PoloAbstract:The electronic rearrangements involved in Noyori Hydrogenation reactions with double bonds (ethene and formaldehyde) are analysed using the bonding evolution theory. The study and analysis of the c...
