Abstract The ester function of ethyl cis-(±)-2-hydroxycyclopentane-1-carboxylate [(±)-1] and ethyl (±)-5-hydroxycyclopent-1-enecarboxylate [(±)-2] was demonstrated to undergo hydrolysis, as a side-reaction, during asymmetric (E> 200) O-acylation with Candida antarctica lipase B (CAL-B) as catalyst and vinyl acetate as acyl donor in t-BuOMe at 30 C. This competition of acylation and undesirable hydrolysis draws attention to CAL-B- ...
