The Experts below are selected from a list of 285 Experts worldwide ranked by ideXlab platform
Min Shi - One of the best experts on this subject based on the ideXlab platform.
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dabco agoac cooperatively catalyzed α sulfenylation of isocyanoacetates with n sulfanyl Succinimides
Tetrahedron Letters, 2019Co-Authors: Meixin Zhao, Qiang Liu, Ronghui Jiang, Min ShiAbstract:Abstract The first organo/metal cooperatively catalyzed α-sulfenylation of isocyanoacetates with N-(sulfanyl)Succinimides has been developed. The reaction condition was suitable to α-aryl and alkyl-substituted isocyanoactates as well as N-(arylthio)Succinimides, affording the corresponding products with high yields (90–96%). Preliminary asymmetric organocatalysis has also been evaluated.
Min Yang - One of the best experts on this subject based on the ideXlab platform.
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unexpected fluorescence from polymers containing dithio amino Succinimides
Polymer Chemistry, 2015Co-Authors: Junjie Yan, Bin Zheng, Donghui Pan, Runlin Yang, Lizhen Wang, Min YangAbstract:Fluorescent polymers without conventional fluorescent units are attracting extensive interest because of their excellent biocompatibility. Succinimides are generally known as common fluorescence quenchers of proteins due to some degree of electron transfer between the excited state and the quencher. In this work, we observed unexpected fluorescence from succinimide-containing polymers. We synthesized a series of Succinimides and found that 2,3-dithio-succinimide and 2-amino-succinimide were fluorescent, presenting solvent-dependent emission. This study is the first to report that nonfluorescent Succinimides become fluorescent only by thiol and amine group substitutions, without employing any fluorescent units. The unusual fluorescence of dithio/amino-Succinimides resulted from the spatial separation of HOMO and LUMO based on density functional theory calculations. Compared with monomers, polymers containing 2-amino-succinimide exhibited substantial fluorescence enhancement (maximum of ∼200-fold) because of the isolation effect, in which nonradiative decay among succinimide fluorophores was significantly suppressed.
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Unexpected fluorescence from polymers containing dithio/amino-Succinimides
Polymer Chemistry, 2015Co-Authors: Junjie Yan, Bin Zheng, Donghui Pan, Runlin Yang, Lizhen Wang, Min YangAbstract:Fluorescent polymers without conventional fluorescent units are attracting extensive interest because of their excellent biocompatibility. Succinimides are generally known as common fluorescence quenchers of proteins due to some degree of electron transfer between the excited state and the quencher. In this work, we observed unexpected fluorescence from succinimide-containing polymers. We synthesized a series of Succinimides and found that 2,3-dithio-succinimide and 2-amino-succinimide were fluorescent, presenting solvent-dependent emission. This study is the first to report that nonfluorescent Succinimides become fluorescent only by thiol and amine group substitutions, without employing any fluorescent units. The unusual fluorescence of dithio/amino-Succinimides resulted from the spatial separation of HOMO and LUMO based on density functional theory calculations. Compared with monomers, polymers containing 2-amino-succinimide exhibited substantial fluorescence enhancement (maximum of ∼200-fold) because of the isolation effect, in which nonradiative decay among succinimide fluorophores was significantly suppressed.
Xumu Zhang - One of the best experts on this subject based on the ideXlab platform.
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Highly Enantioselective Synthesis of Chiral Succinimides via Rh/Bisphosphine-Thiourea-Catalyzed Asymmetric Hydrogenation
ACS Catalysis, 2016Co-Authors: Zhengyu Han, Zongpeng Zhang, Caiyou Chen, Qian Wang, Xiu-qin Dong, Xumu ZhangAbstract:We have successfully developed a highly enantioselective hydrogenation of various 3-aryl and 3-methyl maleinimides to access enantiomerically pure 3-substituted Succinimides catalyzed by Rh/bisphosphine-thiourea (ZhaoPhos). This efficient catalytic system furnished the desired 3-substituted succinimide products with high yields and enantioselectivities (up to 99% yield, full conversions, almost all 3-aryl succinimide products up to 99% ee, and 3-methyl succinimide with 83% ee). Our catalytic system has a strong substrate tolerance and generality. Whether the N-substituted group of maleinimides is H or other protecting groups, the maleinimides were hydrogenated well (up to >99% ee, 99% yield). Moreover, the hydrogenation succinimide products can be readily utilized for the construction of biologically active molecules, such as chiral amides and pyrrolidines.
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Highly Enantioselective Synthesis of Chiral Succinimides via Rh/Bisphosphine-Thiourea-Catalyzed Asymmetric Hydrogenation
2016Co-Authors: Zhengyu Han, Zongpeng Zhang, Caiyou Chen, Qian Wang, Xiu-qin Dong, Xumu ZhangAbstract:We have successfully developed a highly enantioselective hydrogenation of various 3-aryl and 3-methyl maleinimides to access enantiomerically pure 3-substituted Succinimides catalyzed by Rh/bisphosphine-thiourea (ZhaoPhos). This efficient catalytic system furnished the desired 3-substituted succinimide products with high yields and enantioselectivities (up to 99% yield, full conversions, almost all 3-aryl succinimide products up to 99% ee, and 3-methyl succinimide with 83% ee). Our catalytic system has a strong substrate tolerance and generality. Whether the N-substituted group of maleinimides is H or other protecting groups, the maleinimides were hydrogenated well (up to >99% ee, 99% yield). Moreover, the hydrogenation succinimide products can be readily utilized for the construction of biologically active molecules, such as chiral amides and pyrrolidines
Giorgio Bencivenni - One of the best experts on this subject based on the ideXlab platform.
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remote control of axial chirality aminocatalytic desymmetrization of n arylmaleimides via vinylogous michael addition
Journal of the American Chemical Society, 2014Co-Authors: Nicola Di Iorio, Michele Mancinelli, Alessia Ciogli, Paolo Righi, Andrea Mazzanti, Giorgio BencivenniAbstract:Remote control of the axial chirality of N-(2-t-butylphenyl)Succinimides was realized via the vinylogous Michael addition of 3-substituted cyclohexenones to N-(2-t-butylphenyl)maleimides. 9-Amino(9-deoxy)epi-quinine promoted the enantioselective desymmetrization, leading to atropisomeric Succinimides with two adjacent stereocenters.
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Remote Control of Axial Chirality: Aminocatalytic Desymmetrization of N‑Arylmaleimides via Vinylogous Michael Addition
2014Co-Authors: Nicola Di Iorio, Michele Mancinelli, Alessia Ciogli, Paolo Righi, Andrea Mazzanti, Giorgio BencivenniAbstract:Remote control of the axial chirality of N-(2-t-butylphenyl)Succinimides was realized via the vinylogous Michael addition of 3-substituted cyclohexenones to N-(2-t-butylphenyl)maleimides. 9-Amino(9-deoxy)epi-quinine promoted the enantioselective desymmetrization, leading to atropisomeric Succinimides with two adjacent stereocenters
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Remote control of axial chirality: aminocatalytic desymmetrization of N‑arylmaleimides via vinylogous Michael Addition
'American Chemical Society (ACS)', 2014Co-Authors: Nicola Di Iorio, Michele Mancinelli, Paolo Righi, Andrea Mazzanti, Ciogli Alessia, Giorgio BencivenniAbstract:Remote control of the axial chirality of N- (2-t-butylphenyl)Succinimides was realized via the vinylogous Michael addition of 3-substituted cyclohexenones to N-(2-t-butylphenyl)maleimides. 9-Amino(9-deoxy)epi-quinine promoted the enantioselective desymmetrization, leading to atropisomeric Succinimides with two adjacent stereocenters
Junjie Yan - One of the best experts on this subject based on the ideXlab platform.
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unexpected fluorescence from polymers containing dithio amino Succinimides
Polymer Chemistry, 2015Co-Authors: Junjie Yan, Bin Zheng, Donghui Pan, Runlin Yang, Lizhen Wang, Min YangAbstract:Fluorescent polymers without conventional fluorescent units are attracting extensive interest because of their excellent biocompatibility. Succinimides are generally known as common fluorescence quenchers of proteins due to some degree of electron transfer between the excited state and the quencher. In this work, we observed unexpected fluorescence from succinimide-containing polymers. We synthesized a series of Succinimides and found that 2,3-dithio-succinimide and 2-amino-succinimide were fluorescent, presenting solvent-dependent emission. This study is the first to report that nonfluorescent Succinimides become fluorescent only by thiol and amine group substitutions, without employing any fluorescent units. The unusual fluorescence of dithio/amino-Succinimides resulted from the spatial separation of HOMO and LUMO based on density functional theory calculations. Compared with monomers, polymers containing 2-amino-succinimide exhibited substantial fluorescence enhancement (maximum of ∼200-fold) because of the isolation effect, in which nonradiative decay among succinimide fluorophores was significantly suppressed.
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Unexpected fluorescence from polymers containing dithio/amino-Succinimides
Polymer Chemistry, 2015Co-Authors: Junjie Yan, Bin Zheng, Donghui Pan, Runlin Yang, Lizhen Wang, Min YangAbstract:Fluorescent polymers without conventional fluorescent units are attracting extensive interest because of their excellent biocompatibility. Succinimides are generally known as common fluorescence quenchers of proteins due to some degree of electron transfer between the excited state and the quencher. In this work, we observed unexpected fluorescence from succinimide-containing polymers. We synthesized a series of Succinimides and found that 2,3-dithio-succinimide and 2-amino-succinimide were fluorescent, presenting solvent-dependent emission. This study is the first to report that nonfluorescent Succinimides become fluorescent only by thiol and amine group substitutions, without employing any fluorescent units. The unusual fluorescence of dithio/amino-Succinimides resulted from the spatial separation of HOMO and LUMO based on density functional theory calculations. Compared with monomers, polymers containing 2-amino-succinimide exhibited substantial fluorescence enhancement (maximum of ∼200-fold) because of the isolation effect, in which nonradiative decay among succinimide fluorophores was significantly suppressed.
