Abstract Bicyclo [3.2. 0] hept-2-en-6-ols, central building blocks for the synthesis of chiral cyclobutane and-pentane systems, were prepared with up to> 99% ee by lipase catalysed resolution of their acetates, butyrates, or isobutyrates. Substituents at C-7 vicinal to the reaction site reduced both enantioselectivity and reaction rate, whereas variation of the acid moiety showed a smaller influence. Among the lipase tested, those from Pseudomonas sp ...