Regioselective Radical Hydroboration of -Difluoroalkenes: Synthesis of α-Borylated Organofluorines.

Org Lett

Hefei National Laboratory for Physical Sciences at the Microscale, Center for Excellence in Molecular Synthesis of CAS, and Department of Chemistry , University of Science and Technology of China, 96 Jinzhai Road , Hefei , Anhui 230026 , China.

Published: October 2019

A regioselective radical hydroboration of -difluoroalkenes was developed for the synthesis of α-difluoroalkylborons. The reaction features excellent regioselectivity, broad substrate scope, and good functional group capability. DFT calculations implicated the remarkable α-selectivity was driven from the kinetically and thermodynamically more favorable α-addition step. The resulting α-difluoroalkylborons could be readily converted into NHC-borane-tethered monofluoroalkenes, which demonstrated unique reactivity and applicability in the synthesis of monofluoroalkene derivatives through transformations of the boron unit.

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http://dx.doi.org/10.1021/acs.orglett.9b03173DOI Listing

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