Oxazolidinone Synthesis through Halohydrin Dehalogenase-Catalyzed Dynamic Kinetic Resolution

An efficient dynamic kinetic resolution protocol using a single enzyme is described. Both the kinetic resolution and substrate racemization are catalyzed by halohydrin dehalogenase from Agrobacterium radiobacter AD1 (HheC). The HheC-catalyzed reaction of epibromohydrin and 2-bromomethyl-2-methyloxirane with sodium cyanate afforded 5-substituted 2-oxazolidinones in high yields (97% and 87%) and high optical purity (89% and > 99% ee) in the presence of catalytic amounts of bromide ion. These compounds are valuable building blocks with diverse synthetic applications.