Confronting the Challenge of Asymmetric Carbonyl Addition to Sterically Bulky Isatins: Upgrading
Wenjing Guo1, Shuming Zhan1, Han Yang1
1Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, P. R. China.
Abstract:
Catalytic asymmetric addition of arylboronic acids to ketones is a powerful transformation for directly delivering chiral tertiary alcohols. However, there is no successful example of enantioselective addition to steric bulky isatins, which contain bulky substituent at the 4-position. To confront this challenge, in this work a dirhodium/(BTFM-Garphos) system was developed that showed extremely high activity and stereoselectivity, and the reactions were usually finished within a few minutes.
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