An optically active 3-aryl-3-hydroxypropionate 3a was prepared by lipase-catalyzed kinetic hydrolysis of a diastereomeric mixture of 3-aryl-3-(α-chloroacetoxy)propionate 6 in good conversion yield with adequate purity (>95% de). This enzymatic reaction proceeded with great efficiency as measured by reaction rate, chemical yield and stereoselectivity. The compound 3a was converted to J-114,870 1a, a novel ultra-broad spectrum carbapenem, without significant epimerization.