Enzymatic resolution of 2-dialkylaminomethylcyclopentanols and -cycloheptanols

Extensive lipase screening was performed in relation to the asymmetric acetylation of rac-2-dialkylaminomethylcyclanols 1-5. The lipase PS- and Novozym 435-catalysed resolutions of compounds 1-5 were based on asymmetric acylation of the secondary OH group at the R-stereogenic centre with various vinyl eaters, in different organic media. High enantioselectivity (E>200) was observed when vinyl acetate was used as acylating agent, with diethyl ether or with diisopropyl ether as solvent. The reaction rates were markedly affected by the size of the alicyclic ring, and by the solvent. (C) 1999 Elsevier Science Ltd. All rights reserved.