highly carbon‐selective difluoromethylation of soft carbon nucleophiles including β‐ketoesters, malonates, oxindoles, benzofuranones and ketenesilylacetals with a difluoromethylated sulfonium ylide under mild conditions was described. Mechanistic studies suggest that these difluoromethylating reactions proceed via a difluorocarbene pathway.
Chiral Calcium Phosphate Catalyzed Enantioselective Amination of 3-Aryl-2-benzofuranones
作者:Ruihan Liu、Suvratha Krishnamurthy、Zhenwei Wu、K. S. Satyanarayana Tummalapalli、Jon C. Antilla
DOI:10.1021/acs.orglett.0c03059
日期:2020.10.16
4-tert-butyl-phenyl substituted (R)-[H8]-BINOL chiral calcium phosphate catalyzedenantioselectiveamination of 3-aryl-2-benzofuranones with dibenzyl azodicarboxylate is described. The catalyst loading of the reaction is 1 mol %. This transformation is facile and has a high degree atom economy, which gave products with good yields and high enantioselectivities (79% to 99%). This reaction has excellent ee
Organocatalytic Asymmetric Branching Sequence of MBH Carbonates: Access to Chiral Benzofuran-2(3<i>H</i>)-one Derivatives with Three Stereocenters
作者:Chuanle Zhu、Lijun Yang、Jing Nie、Yan Zheng、Junan Ma
DOI:10.1002/cjoc.201200809
日期:2012.11
An organocatalyticasymmetricbranchingsequence was realized in the presence of 10 mol% of (DHQD)2AQN, affording the sequential products with three stereocentres, including two quaternary carbon centres, in 47%–79% yields with 85%–99% ee.
An organocatalytic asymmetric reaction of benzofuran-2(3H)-ones with naphthoquinones is disclosed. The current method provides a direct way to furnish arylation of benzofuran-2(3H)-ones in high yields with excellent enantioselectivities. A cooperative...
An efficient, chiralbifunctional phase-transfer catalyst with an intramolecular amino functionality has been designed and successfully applied to highly enantioselective amination of 3-aryloxindoles and 3-arylbenzofuran-2(3H)-ones with bis(adamantyl) azodicarboxylate. Optically active amination products were generally obtained in high yield with high enantioselectivity. The origin of stereoselectivity