Dynamic Kinetic Resolution for Construction of Three Transannular Stereocenters of Dihydrobenzofuranols.

A handy and effective method was established to obtain the cis-2,3-dihydrobenzofuranols having three stereocenters, involving asymmetric transfer hydrogenation of benzofuranones via dynamic kinetic resolution. The general applicability of this method was examined with different benzofuran-3-(2 H)-ones, and stereoselectivities of 85-99% ee and up to 98/2 dr were obtained.