Catalytic Atroposelective Dynamic Kinetic Resolution of Biaryl Lactones with Activated Isocyanides
Linghui Qian1, Ling-Fei Tao1, Wen-Tao Wang1
1College of Pharmaceutical Sciences, and Hangzhou Institute of Innovative Medicine, Zhejiang University, Hangzhou 310058, China.
Abstract:
We report herein an unprecedented atroposelective dynamic kinetic resolution of Bringmann's lactones with C-nucleophiles. By the use of activated isocyanides as the reagent, a wide range of novel axially chiral oxazole-substituted biaryl phenols were accessed in high yields with high enantioselectivities. Key to the success of this process lies in the tandem atroposelective addition of isocyanides to the lactone substrate followed by a rapid cyclization, overcoming the challenge of stereochemical leakage induced by lactol formation.
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