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Yian Shi - One of the best experts on this subject based on the ideXlab platform.
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Phosphine Oxide sc otf 3 catalyzed highly regio and enantioselective bromoaminocyclization of e cinnamyl tosylcarbamates an approach to a class of synthetically versatile functionalized molecules
Organic Letters, 2016Co-Authors: Hongjie Pan, Yian Shi, Hu Huang, Weigang Liu, Hua TianAbstract:A highly regio- and enantioselective bromoaminocyclization of (E)-cinnamyl tosylcarbamates catalyzed by a chiral Phosphine Oxide-Sc(OTf)3 complex is described. A wide variety of optically active aryl 5-bromo-1,3-oxazinan-2-ones can be obtained with high yield and enantioselectivity.
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chiral Phosphine Oxide sc otf 3 complex catalyzed enantioselective bromoaminocyclization of 2 benzofuranylmethyl n tosylcarbamates approach to a novel class of optically active spiro compounds
Organic Letters, 2015Co-Authors: Yian ShiAbstract:An efficient enantioselective bromoaminocyclization of 2-benzofuranylmethyl N-tosylcarbamates catalyzed by a chiral Phosphine Oxide-Sc(OTf)(3) complex is described. A wide variety of optically active spiro benzofuran oxazolidinones can be obtained with high enantioselectivities.
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enantioselective 6 endo bromoaminocyclization of 2 4 dienyl n tosylcarbamates catalyzed by a chiral Phosphine Oxide sc otf 3 complex a dramatic additive effect
Organic and Biomolecular Chemistry, 2015Co-Authors: Hu Huang, Yian Shi, Hongjie Pan, Hua Tian, Yudong Cai, Mao LiuAbstract:An effective enantioselective 6-endo bromoaminocyclization of 2,4-dienyl N-tosylcarbamates catalyzed by a chiral Phosphine Oxide-Sc(OTf)(3) complex is described. A wide variety of optically active 5-bromo-1,3-oxazinan-2-ones containing various functional groups can be obtained in 61-91% yields and 92-99% ees. An additive, such as NaCl, has been found to be crucial for the reaction process.
Makoto Nakajima - One of the best experts on this subject based on the ideXlab platform.
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Recent advances in asymmetric Phosphine Oxide catalysis
Tetrahedron Letters, 2020Co-Authors: Shunsuke Kotani, Makoto NakajimaAbstract:Abstract Phosphine Oxides are versatile catalysts in organic synthesis and mediate a broad range of transformations. In this digest, we reviewed the recent developments in Phosphine Oxide-catalyzed asymmetric reactions. The enantioselective double aldol reactions, enantioselective aldol reaction of carboxylic acids, and enantioselective halocyclizations were discussed. These novel Phosphine Oxide-catalyzed processes are vital for the stereoselective synthesis and functionalization of useful organic molecules and intermediates.
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catalytic enantioselective aldol reactions of unprotected carboxylic acids under Phosphine Oxide catalysis
Angewandte Chemie, 2018Co-Authors: Shunsuke Kotani, Masaharu Sugiura, Masamichi Ogasawara, Yusaku Yoshiwara, Makoto NakajimaAbstract:The first catalytic enantioselective aldol reaction of various unprotected carboxylic acids is described. In the presence of a chiral bis(Phosphine Oxide) as a Lewis base catalyst, carboxylic acids were activated with silicon tetrachloride to form the corresponding bis(trichlorosilyl)enediolates in situ, which subsequently underwent an aldol reaction with an aldehyde or a ketone to produce β-hydroxycarboxylic acids in high enantioselectivities of up to 92 % ee.
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Stereoselective Synthesis of Highly Functionalized 2,3-Dihydro-4-pyranones Using Phosphine Oxide as Catalyst
Chemical & pharmaceutical bulletin, 2016Co-Authors: Shunsuke Kotani, Shiki Miyazaki, Kazuya Kawahara, Yasushi Shimoda, Masaharu Sugiura, Makoto NakajimaAbstract:2,3-Dihydro-4-pyranones were synthesized stereoselectively using a chiral Phosphine Oxide as the catalyst. The Phosphine Oxide sequentially activated silicon tetrachloride and promoted the double aldol reaction of 4-methoxy-3-buten-2-one with aldehydes. Subsequent stereoselective cyclization afforded the corresponding highly functionalized 2,3-dihydro-4-pyranones bearing three contiguous chiral centers in good yields and with high diastereo- and enantioselectivities.
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Phosphine Oxide catalyzed enantioselective intramolecular aldol reaction via regioselective enolization of unsymmetrical diketones with tetrachlorosilane
Organic Letters, 2014Co-Authors: Shunsuke Kotani, Masaharu Sugiura, Masamichi Ogasawara, Shohei Aoki, Makoto NakajimaAbstract:The Phosphine Oxide-catalyzed asymmetric intramolecular aldol reactions of diketones were investigated. The combination of tetrachlorosilane and a chiral Phosphine Oxide catalyst promoted the acetyl-selective enolization of diketones, and the subsequent intramolecular aldol reaction occurred in an enantioselective manner. The introduction of two trimethylsilyl groups at the 4- and 4′-positions in BINAP diOxide catalyst improved the enantioselectivity. This reaction provides an effective synthetic method to access β-tertiary-hydroxy cyclohexanones in high yields and with high enantioselectivity.
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enantioselective morita baylis hillman reaction catalyzed by a chiral Phosphine Oxide
ChemInform, 2014Co-Authors: Shunsuke Kotani, Masaharu Sugiura, Masaya Ito, Hirono Nozaki, Masamichi Ogasawara, Makoto NakajimaAbstract:A hypervalent silicon complex generated from a chiral Phosphine Oxide catalyst and SiCl4 reacts with vinyl ketones (I) to give the corresponding γ-chloro silyl enol ether intermediates.
Hongjie Pan - One of the best experts on this subject based on the ideXlab platform.
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Phosphine Oxide sc otf 3 catalyzed highly regio and enantioselective bromoaminocyclization of e cinnamyl tosylcarbamates an approach to a class of synthetically versatile functionalized molecules
Organic Letters, 2016Co-Authors: Hongjie Pan, Yian Shi, Hu Huang, Weigang Liu, Hua TianAbstract:A highly regio- and enantioselective bromoaminocyclization of (E)-cinnamyl tosylcarbamates catalyzed by a chiral Phosphine Oxide-Sc(OTf)3 complex is described. A wide variety of optically active aryl 5-bromo-1,3-oxazinan-2-ones can be obtained with high yield and enantioselectivity.
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enantioselective 6 endo bromoaminocyclization of 2 4 dienyl n tosylcarbamates catalyzed by a chiral Phosphine Oxide sc otf 3 complex a dramatic additive effect
Organic and Biomolecular Chemistry, 2015Co-Authors: Hu Huang, Yian Shi, Hongjie Pan, Hua Tian, Yudong Cai, Mao LiuAbstract:An effective enantioselective 6-endo bromoaminocyclization of 2,4-dienyl N-tosylcarbamates catalyzed by a chiral Phosphine Oxide-Sc(OTf)(3) complex is described. A wide variety of optically active 5-bromo-1,3-oxazinan-2-ones containing various functional groups can be obtained in 61-91% yields and 92-99% ees. An additive, such as NaCl, has been found to be crucial for the reaction process.
Hu Huang - One of the best experts on this subject based on the ideXlab platform.
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Phosphine Oxide sc otf 3 catalyzed highly regio and enantioselective bromoaminocyclization of e cinnamyl tosylcarbamates an approach to a class of synthetically versatile functionalized molecules
Organic Letters, 2016Co-Authors: Hongjie Pan, Yian Shi, Hu Huang, Weigang Liu, Hua TianAbstract:A highly regio- and enantioselective bromoaminocyclization of (E)-cinnamyl tosylcarbamates catalyzed by a chiral Phosphine Oxide-Sc(OTf)3 complex is described. A wide variety of optically active aryl 5-bromo-1,3-oxazinan-2-ones can be obtained with high yield and enantioselectivity.
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enantioselective 6 endo bromoaminocyclization of 2 4 dienyl n tosylcarbamates catalyzed by a chiral Phosphine Oxide sc otf 3 complex a dramatic additive effect
Organic and Biomolecular Chemistry, 2015Co-Authors: Hu Huang, Yian Shi, Hongjie Pan, Hua Tian, Yudong Cai, Mao LiuAbstract:An effective enantioselective 6-endo bromoaminocyclization of 2,4-dienyl N-tosylcarbamates catalyzed by a chiral Phosphine Oxide-Sc(OTf)(3) complex is described. A wide variety of optically active 5-bromo-1,3-oxazinan-2-ones containing various functional groups can be obtained in 61-91% yields and 92-99% ees. An additive, such as NaCl, has been found to be crucial for the reaction process.
Hua Tian - One of the best experts on this subject based on the ideXlab platform.
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Phosphine Oxide sc otf 3 catalyzed highly regio and enantioselective bromoaminocyclization of e cinnamyl tosylcarbamates an approach to a class of synthetically versatile functionalized molecules
Organic Letters, 2016Co-Authors: Hongjie Pan, Yian Shi, Hu Huang, Weigang Liu, Hua TianAbstract:A highly regio- and enantioselective bromoaminocyclization of (E)-cinnamyl tosylcarbamates catalyzed by a chiral Phosphine Oxide-Sc(OTf)3 complex is described. A wide variety of optically active aryl 5-bromo-1,3-oxazinan-2-ones can be obtained with high yield and enantioselectivity.
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enantioselective 6 endo bromoaminocyclization of 2 4 dienyl n tosylcarbamates catalyzed by a chiral Phosphine Oxide sc otf 3 complex a dramatic additive effect
Organic and Biomolecular Chemistry, 2015Co-Authors: Hu Huang, Yian Shi, Hongjie Pan, Hua Tian, Yudong Cai, Mao LiuAbstract:An effective enantioselective 6-endo bromoaminocyclization of 2,4-dienyl N-tosylcarbamates catalyzed by a chiral Phosphine Oxide-Sc(OTf)(3) complex is described. A wide variety of optically active 5-bromo-1,3-oxazinan-2-ones containing various functional groups can be obtained in 61-91% yields and 92-99% ees. An additive, such as NaCl, has been found to be crucial for the reaction process.