A biocatalyticapproach towards a range of 4‐aryloxazolidinones is developed using a halohydrin dehalogenase from Ilumatobacter coccineus (HheG) as biocatalyst. The method is based on the HheG‐catalyzed α‐position regioselective ring‐opening of styrene oxide derivatives with cyanate as a nucleophile, producing the corresponding 4‐aryloxazolidinones in moderate to good yields. Synthesis of enantiopure
enantio‐ and regioselective ring‐opening of styrene oxides with cyanate was developed by using the halohydrin dehalogenase HheC from Agrobacterium radiobacter AD1, generating the corresponding chiral 5‐aryl‐2‐oxazolidinones in up to 47% yield and 90% ee. Additionally, the origin of enantioselectivity and regioselectivity of the HheC‐catalyzed cyanate‐mediatedring‐opening process was uncovered by single