Trifluoromethylborylation of Unactivated Alkenes via an Electron Donor-Acceptor (EDA) Complex
1Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405-7102, United States.
Abstract:
This communication describes a straightforward method for the trifluoromethylborylation of unactivated alkenes. The reaction proceeds through the formation of an electron donor-acceptor (EDA) complex between a trifluoromethylthiophenium salt and bis(catechol)diboron under broad-spectrum white-light irradiation. Due to the mild reaction conditions, the trifluoromethylborylation tolerates a wide range of functional groups, including esters, acids, alcohols, epoxides, and a variety of heterocycles. The reaction does not require a transition metal catalyst and tolerates both air and moisture, proceeding under concentrated conditions (1 M). Mechanistic studies provide a general reaction coordinate for the overall transformation.
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