Chemoenzymatic synthesis of (S)-moprolol

Herein we describe part of the chemoenzymatic synthesis of (S)-moprolol, starting from commercially available 2-methoxyphenol (I), Scheme 1. Initially, the reaction between phenol I and epichlorohydrin resulted in a mixture of chlorohydrin II (66%) and the epoxide III (22%). Since the goal was to obtain the chlorohydrin II, epoxide III was treated with concentrated HCl to produce II with an overall yield of 87%. Then, the chlorohydrin II was converted into the corresponding acetate IV in a yield of 93%.