Rhodium-catalyzed regioselective opening of vinyl epoxides with Et3N·3HF reagent – formation of allylic fluorohydrins

Abstract

A highly regioselective rhodium-catalyzed ring-opening of vinyl epoxides with Et₃N·3HF reagent to form branched allylic fluorohydrins is described. The reaction occurs at room temperature under ambient air and relies on RhCOD₂BF₄ as an effective catalyst, providing the desired 1,2-addition allylic fluorohydrins in moderate to good yields with excellent levels of regioselectivity. Mechanistic studies demonstrate that the regioselective ring-opening of enantiopure vinyl epoxide occurs with inversion of stereochemistry.