Palladium-catalyzed stereospecific epoxide-opening reaction of (gamma),(delta)-epoxy-(alpha),(beta)-unsaturated esters with an alkylboronic acid leading to (gamma),(delta)-vicinal diols with double inversion of the configuration

A palladium-catalyzed stereospecific epoxide-opening reaction of (gamma),(delta)-epoxy-(alpha),(beta)-unsaturated esters with an alkylboronic acid leading to (gamma),(delta)-vicinal diols is described, which proceeds with retention of the configuration, i.e., via two consecutive SN2 processes, to afford the corresponding (gamma),(delta)-cyclic boronates in high yields.