The development of catalytic asymmetric methods that enable access to value-added functionalities or structures,exemplified by allylic alcohols,is a highly interesting yet challenging topic from both academic and indu...The development of catalytic asymmetric methods that enable access to value-added functionalities or structures,exemplified by allylic alcohols,is a highly interesting yet challenging topic from both academic and industrial perspectives.However,before recent advances in chemical catalysis,there were scarce protocols toward constructing enantioenriched tertiary allylic alcohol scaffolds.In this context,peptide-mimic phosphonium salts were found to be highly efficient in catalytic asymmetricα-hydroxylation ofα,β-unsaturated and/orβ,Y-unsaturated compounds with satisfactory regio-and stereochemical outcomes(up to 97%yield and 95%ee).This methodology tolerates a broad array of substrates and thus provides an expeditious and unified platform for the assembly of enantioenriched tertiary allylic alcohols by avoiding the use of additional reductants and expensive metal catalysts.Furthermore,the power of this protocol is enlarged by simple conditions and the use of air as a source of hydroxyl functionality.展开更多
Kinetic resolution is one of the most commonly used methods allowing access to enantioenriched compounds.The last two decades have seen the rapid development of kinetic resolutions enabled by N-heterocyclic carbene ca...Kinetic resolution is one of the most commonly used methods allowing access to enantioenriched compounds.The last two decades have seen the rapid development of kinetic resolutions enabled by N-heterocyclic carbene catalysis,and part of the achievements have been summarized in our previous review paper published in 2017.Since then,a series of new advances have been realized,and this review will provide an update of this field covering reports from mid-2017 to 2023.展开更多
Transition-metal-catalyzed cross-coupling reactions have revolutionized synthetic approaches for forging C-C bonds.However,catalytic enantioconvergent couplings of racemic secondary organometallics with aryl electroph...Transition-metal-catalyzed cross-coupling reactions have revolutionized synthetic approaches for forging C-C bonds.However,catalytic enantioconvergent couplings of racemic secondary organometallics with aryl electrophiles remain a significant challenge.We herein describe a rare Pd-catalyzed enantioconvergent coupling of sec-alkylzinc reagents with aryl halides,providing a range of enantioenriched 1,1-diarylalkane products in excellent yield(up to 99%)and high enantioselectivity(up to 95.5:4.5 er).The reaction showed broad substrate scope and excellent functional group tolerance and was efficiently applied to the modification of pharmaceutically relevant molecules.The use of a bulky C2-symmetric chiral N-heterocyclic carbene(NHC)ligand for palladium catalyst was key to attaining high reactivity and enantioselectivity.Mechanistic studies and density functional theory calculations elucidated the enantioselectivity-determining transmetalation step and the origins of enantiocontrol by the NHC ligand.展开更多
基金Financial support was provided by the National Natural Science Foundation of China(22222109,21921002,22101189 and 22371190)the National Key R&DProgramof China(2018YFA0903500)+3 种基金Beijing National Laboratory for Molecular Sciences(BNLMs202101)Sichuan Science Foundation for Distinguished Young Scholars(2023NSFSC1921)Sichuan Provincial Natural Science Foundation(2022NSFSC1181,24NSFSC6590)Fundamental Research Funds from Sichuan University(2020SCUNL108)and Fundamental Research Funds for the Central Universities.
文摘The development of catalytic asymmetric methods that enable access to value-added functionalities or structures,exemplified by allylic alcohols,is a highly interesting yet challenging topic from both academic and industrial perspectives.However,before recent advances in chemical catalysis,there were scarce protocols toward constructing enantioenriched tertiary allylic alcohol scaffolds.In this context,peptide-mimic phosphonium salts were found to be highly efficient in catalytic asymmetricα-hydroxylation ofα,β-unsaturated and/orβ,Y-unsaturated compounds with satisfactory regio-and stereochemical outcomes(up to 97%yield and 95%ee).This methodology tolerates a broad array of substrates and thus provides an expeditious and unified platform for the assembly of enantioenriched tertiary allylic alcohols by avoiding the use of additional reductants and expensive metal catalysts.Furthermore,the power of this protocol is enlarged by simple conditions and the use of air as a source of hydroxyl functionality.
文摘Kinetic resolution is one of the most commonly used methods allowing access to enantioenriched compounds.The last two decades have seen the rapid development of kinetic resolutions enabled by N-heterocyclic carbene catalysis,and part of the achievements have been summarized in our previous review paper published in 2017.Since then,a series of new advances have been realized,and this review will provide an update of this field covering reports from mid-2017 to 2023.
基金supported by the National Key R&D Program of China(grant no.2021YFF0701600)the National Natural Science Foundation of China(grant nos.22325110,92256303,22171280,22401288,22122109,and 22271253)+6 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(grant no.XDB0610000)the Program of Shanghai Academic Research Leader(grant no.22XD1424900)the Shanghai Science and Technology Committee(grant no.24ZR1479000)the Chinese Academy of Sciences Youth Interdisciplinary Team(grant no.JCTD-2021-11)the Ningbo Natural Science Foundation(grant no.2022J017)Zhejiang Provincial Natural Science Foundation of China(grant no.LDQ23B020002)the Leading Innovation Team grant from Department of Science and Technology of Zhejiang Province(grant no.2022R01005).
文摘Transition-metal-catalyzed cross-coupling reactions have revolutionized synthetic approaches for forging C-C bonds.However,catalytic enantioconvergent couplings of racemic secondary organometallics with aryl electrophiles remain a significant challenge.We herein describe a rare Pd-catalyzed enantioconvergent coupling of sec-alkylzinc reagents with aryl halides,providing a range of enantioenriched 1,1-diarylalkane products in excellent yield(up to 99%)and high enantioselectivity(up to 95.5:4.5 er).The reaction showed broad substrate scope and excellent functional group tolerance and was efficiently applied to the modification of pharmaceutically relevant molecules.The use of a bulky C2-symmetric chiral N-heterocyclic carbene(NHC)ligand for palladium catalyst was key to attaining high reactivity and enantioselectivity.Mechanistic studies and density functional theory calculations elucidated the enantioselectivity-determining transmetalation step and the origins of enantiocontrol by the NHC ligand.
