Enantioselective α-C(sp3)-H Borylation of Masked Primary Alcohols Enabled by Iridium Catalysis
Qian Gao1,2, Yinwu Li3, Lili Chen1
1State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China.
Abstract:
Functional group-directed site- and enantioselective C(sp3)-H functionalization of alcohols or masked alcohols represents a formidable challenge. We herein report the first example of iridium-catalyzed asymmetric α-C(sp3)-H borylation of primary alcohol-derived carbamates by the judicious choice of directing groups. A variety of chiral borylated carbamates were obtained with good to high enantioselectivities. We also demonstrated the synthetic utility by taking advantage of the highly transformable feature of C-B bonds and the leaving ability of carbamates.
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