Enantioselective Hydrolactonization Catalyzed by Chiral Borophosphates
Kuai Yu1,2, Xiangqing Feng1,2, Haifeng Du1,2
1Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
Abstract:
The direct asymmetric hydrolactonization of olefinic carboxylic acids without the aid of electrophilic initiators remains a significant challenge in synthetic chemistry. Herein, we report an enantioselective, metal-free hydrolactonization of olefinic carboxylic acids utilizing an in situ-generated chiral borophosphate as the catalyst. A variety of optically active lactones were obtained in excellent yields with good to high enantioselectivities. This protocol provides a facile and efficient approach to the construction of lactones bearing methyl-substituted tertiary stereocenters.
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