The Experts below are selected from a list of 39918 Experts worldwide ranked by ideXlab platform
Choon-hong Tan - One of the best experts on this subject based on the ideXlab platform.
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catalytic diastereoselective tandem conjugate addition Elimination Reaction of morita baylis hillman c adducts by c c bond cleavage
Chemistry-an Asian Journal, 2012Co-Authors: Wenguo Yang, Choon-hong Tan, Davin Tan, Richmond Lee, Yuanhang Pan, Kuowei Huang, Zhiyong JiangAbstract:Through the cleavage of the C-C bond, the first catalytic tandem conjugate addition-Elimination Reaction of Morita-Baylis-Hillman C adducts has been presented. Various S(N)2'-like C-, S-, and P-allylic compounds could be obtained with exclusive E configuration in good to excellent yields. The Michael product could also be easily prepared by tuning the β-C-substituent group of the α-methylene ester under the same Reaction conditions. Calculated relative energies of various transition states by DFT methods strongly support the observed chemoselectivity and diastereoselectivity.
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tandem conjugate addition Elimination Reaction promoted by chiral pyrrolidinyl sulfonamide cps
Chemical Communications, 2008Co-Authors: Ruijuan Low, Yong-peng Goh, Zhiyong Jiang, Choon-hong TanAbstract:Chiral pyrrolidinyl sulfonamides have been found to promote the conjugate addition-Elimination Reaction between activated allylic bromides and 1,3-dicarbonyl compounds with high enantioselectivities and the highly functionalised products can be used to generate a variety of interesting enantiomerically pure compounds via simple transformations.
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Tandem conjugate addition–Elimination Reaction promoted by chiral pyrrolidinyl sulfonamide (CPS)
Chemical Communications, 2008Co-Authors: Ruijuan Low, Yong-peng Goh, Zhiyong Jiang, Choon-hong TanAbstract:Chiral pyrrolidinyl sulfonamides have been found to promote the conjugate addition-Elimination Reaction between activated allylic bromides and 1,3-dicarbonyl compounds with high enantioselectivities and the highly functionalised products can be used to generate a variety of interesting enantiomerically pure compounds via simple transformations.
Zhiyong Jiang - One of the best experts on this subject based on the ideXlab platform.
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catalytic diastereoselective tandem conjugate addition Elimination Reaction of morita baylis hillman c adducts by c c bond cleavage
Chemistry-an Asian Journal, 2012Co-Authors: Wenguo Yang, Choon-hong Tan, Davin Tan, Richmond Lee, Yuanhang Pan, Kuowei Huang, Zhiyong JiangAbstract:Through the cleavage of the C-C bond, the first catalytic tandem conjugate addition-Elimination Reaction of Morita-Baylis-Hillman C adducts has been presented. Various S(N)2'-like C-, S-, and P-allylic compounds could be obtained with exclusive E configuration in good to excellent yields. The Michael product could also be easily prepared by tuning the β-C-substituent group of the α-methylene ester under the same Reaction conditions. Calculated relative energies of various transition states by DFT methods strongly support the observed chemoselectivity and diastereoselectivity.
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tandem conjugate addition Elimination Reaction promoted by chiral pyrrolidinyl sulfonamide cps
Chemical Communications, 2008Co-Authors: Ruijuan Low, Yong-peng Goh, Zhiyong Jiang, Choon-hong TanAbstract:Chiral pyrrolidinyl sulfonamides have been found to promote the conjugate addition-Elimination Reaction between activated allylic bromides and 1,3-dicarbonyl compounds with high enantioselectivities and the highly functionalised products can be used to generate a variety of interesting enantiomerically pure compounds via simple transformations.
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Tandem conjugate addition–Elimination Reaction promoted by chiral pyrrolidinyl sulfonamide (CPS)
Chemical Communications, 2008Co-Authors: Ruijuan Low, Yong-peng Goh, Zhiyong Jiang, Choon-hong TanAbstract:Chiral pyrrolidinyl sulfonamides have been found to promote the conjugate addition-Elimination Reaction between activated allylic bromides and 1,3-dicarbonyl compounds with high enantioselectivities and the highly functionalised products can be used to generate a variety of interesting enantiomerically pure compounds via simple transformations.
Valerie Vaissier Welborn - One of the best experts on this subject based on the ideXlab platform.
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interplay of water and a supramolecular capsule for catalysis of reductive Elimination Reaction from gold
Nature Communications, 2020Co-Authors: Valerie Vaissier Welborn, Teresa HeadgordonAbstract:Supramolecular assemblies have gained tremendous attention due to their ability to catalyze Reactions with the efficiencies of natural enzymes. Using ab initio molecular dynamics, we identify the origin of the catalysis by the supramolecular capsule Ga4L612- on the reductive Elimination Reaction from gold complexes and assess their similarity to natural enzymes. By comparing the free energies of the reactants and transition states for the catalyzed and uncatalyzed Reactions, we determine that an encapsulated water molecule generates electric fields that contributes the most to the reduction in the activation free energy. Although this is unlike the biomimetic scenario of catalysis through direct host-guest interactions, the electric fields from the nanocage also supports the transition state to complete the reductive Elimination Reaction with greater catalytic efficiency. However it is also shown that the nanocage poorly organizes the interfacial water, which in turn creates electric fields that misalign with the breaking bonds of the substrate, thus identifying new opportunities for catalytic design improvements in nanocage assemblies.
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Interplay of water and a supramolecular capsule for catalysis of reductive Elimination Reaction from gold
Nature Communications, 2020Co-Authors: Valerie Vaissier Welborn, Wan-lu Li, Teresa Head-gordonAbstract:Supramolecular catalytic assemblies attract enormous interest due to their activity that rivals natural enzymes. Using ab initio molecular dynamics, the authors show that a gold catalyst in a Ga_4L_612^- nanocage, while impeded by reorganization energy, is accelerated by hosting a catalytic water molecule. Supramolecular assemblies have gained tremendous attention due to their ability to catalyze Reactions with the efficiencies of natural enzymes. Using ab initio molecular dynamics, we identify the origin of the catalysis by the supramolecular capsule Ga_4L_6^12− on the reductive Elimination Reaction from gold complexes and assess their similarity to natural enzymes. By comparing the free energies of the reactants and transition states for the catalyzed and uncatalyzed Reactions, we determine that an encapsulated water molecule generates electric fields that contributes the most to the reduction in the activation free energy. Although this is unlike the biomimetic scenario of catalysis through direct host-guest interactions, the electric fields from the nanocage also supports the transition state to complete the reductive Elimination Reaction with greater catalytic efficiency. However it is also shown that the nanocage poorly organizes the interfacial water, which in turn creates electric fields that misalign with the breaking bonds of the substrate, thus identifying new opportunities for catalytic design improvements in nanocage assemblies.
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interplay of water and a supramolecular capsule for catalysis of reductive Elimination Reaction from gold
arXiv: Chemical Physics, 2019Co-Authors: Valerie Vaissier Welborn, Teresa HeadgordonAbstract:Supramolecular assemblies have gained tremendous attention due to their apparent ability to catalyze Reactions with the efficiencies of natural enzymes. Using Born-Oppenheimer molecular dynamics and density functional theory, we identify the origin of the catalytic power of the supramolecular assembly Ga$_4$L$_{612-}$ on the reductive Elimination Reaction from gold complexes and their similarity to enzymes. By comparing the catalyzed and uncatalyzed Reaction in explicit solvent to identify the Reaction free energies of the reactants, transition states, and products, we determine that a catalytic moiety -- an encapsulated water molecule -- generates electric fields that contribute significant reduction in the activation free energy. Although this is unlike the biomimetic scenario of catalysis through direct host-guest interactions, the nanocage host preconditions the transition state for greater sensitivity to electric field projections onto the breaking carbon bonds to complete the reductive Elimination Reaction with greater catalytic efficiency. However it is also shown that the nanocage poorly organizes the interfacial water, which in turn creates electric fields that misalign with the breaking bonds of the substrate, thus identifying new opportunities for catalytic design improvements in nanocage assemblies.
Wenguo Yang - One of the best experts on this subject based on the ideXlab platform.
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catalytic diastereoselective tandem conjugate addition Elimination Reaction of morita baylis hillman c adducts by c c bond cleavage
Chemistry-an Asian Journal, 2012Co-Authors: Wenguo Yang, Choon-hong Tan, Davin Tan, Richmond Lee, Yuanhang Pan, Kuowei Huang, Zhiyong JiangAbstract:Through the cleavage of the C-C bond, the first catalytic tandem conjugate addition-Elimination Reaction of Morita-Baylis-Hillman C adducts has been presented. Various S(N)2'-like C-, S-, and P-allylic compounds could be obtained with exclusive E configuration in good to excellent yields. The Michael product could also be easily prepared by tuning the β-C-substituent group of the α-methylene ester under the same Reaction conditions. Calculated relative energies of various transition states by DFT methods strongly support the observed chemoselectivity and diastereoselectivity.
Teresa Headgordon - One of the best experts on this subject based on the ideXlab platform.
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interplay of water and a supramolecular capsule for catalysis of reductive Elimination Reaction from gold
Nature Communications, 2020Co-Authors: Valerie Vaissier Welborn, Teresa HeadgordonAbstract:Supramolecular assemblies have gained tremendous attention due to their ability to catalyze Reactions with the efficiencies of natural enzymes. Using ab initio molecular dynamics, we identify the origin of the catalysis by the supramolecular capsule Ga4L612- on the reductive Elimination Reaction from gold complexes and assess their similarity to natural enzymes. By comparing the free energies of the reactants and transition states for the catalyzed and uncatalyzed Reactions, we determine that an encapsulated water molecule generates electric fields that contributes the most to the reduction in the activation free energy. Although this is unlike the biomimetic scenario of catalysis through direct host-guest interactions, the electric fields from the nanocage also supports the transition state to complete the reductive Elimination Reaction with greater catalytic efficiency. However it is also shown that the nanocage poorly organizes the interfacial water, which in turn creates electric fields that misalign with the breaking bonds of the substrate, thus identifying new opportunities for catalytic design improvements in nanocage assemblies.
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interplay of water and a supramolecular capsule for catalysis of reductive Elimination Reaction from gold
arXiv: Chemical Physics, 2019Co-Authors: Valerie Vaissier Welborn, Teresa HeadgordonAbstract:Supramolecular assemblies have gained tremendous attention due to their apparent ability to catalyze Reactions with the efficiencies of natural enzymes. Using Born-Oppenheimer molecular dynamics and density functional theory, we identify the origin of the catalytic power of the supramolecular assembly Ga$_4$L$_{612-}$ on the reductive Elimination Reaction from gold complexes and their similarity to enzymes. By comparing the catalyzed and uncatalyzed Reaction in explicit solvent to identify the Reaction free energies of the reactants, transition states, and products, we determine that a catalytic moiety -- an encapsulated water molecule -- generates electric fields that contribute significant reduction in the activation free energy. Although this is unlike the biomimetic scenario of catalysis through direct host-guest interactions, the nanocage host preconditions the transition state for greater sensitivity to electric field projections onto the breaking carbon bonds to complete the reductive Elimination Reaction with greater catalytic efficiency. However it is also shown that the nanocage poorly organizes the interfacial water, which in turn creates electric fields that misalign with the breaking bonds of the substrate, thus identifying new opportunities for catalytic design improvements in nanocage assemblies.
