Visible-Light-Induced Regioselective Functionalization of α-Olefin: Development of One-Pot Photo-Synthesis of
Saki Maejima1, Eiji Yamaguchi1, Akichika Itoh1
1Laboratory of Pharmaceuticals Synthetic Chemistry, Gifu Pharmaceutical University 1-25-4 Daigaku-nishi, Gifu 501-1196, Japan.
Abstract:
A method for the catalytic regioselective synthesis of C3-substituted dihydrobenzofurans (DHBs) via [2 + 2] photocycloaddition of alkene and p-benzoquinone is developed. This method realizes the rapid synthesis of DHBs with readily available substrates and simple reaction conditions by using Lewis acid B(C6F5)3 and Lewis base P(o-tol)3 as a catalyst in combination with the classical Paternò-Büchi reaction.
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