LIPASE AKG MEDIATED RESOLUTIONS OF ALPHA,ALPHA-DISUBSTITUTED 1,2-DIOLS IN ORGANIC-SOLVENTS - REMARKABLY HIGH REGIOSELECTIVITY AND ENANTIOSELECTIVITY

Diols 1, which contain adjacent tertiary and primary hydroxy groups, c an be selectively mono-acylated at the primary hydroxy group by many l ipases in organic solvents, Since the reaction does not take place at the chiral tertiary centre itself, observed enantioselectivities are u sually low. Only the combination of one lipase, lipase AKG (Amano, Pse udomonas sp.), with selected substrates gives high enantioselectivitie s (E 20 to > 200), Also, the solvent and acyl donor employed influence s the outcome, On the basis of the results of Lipase AKG towards subst rates 1 an active site model for this specific lipase has been develop ed, which can account for the results obtained, Fu!! experimental deta ils on the synthesis of diols 1 and enzymatic preparation of acetates 2 are given, Also, the absolute stereochemistry of the enzymatically p repared diols 1 has been established by independent synthesis from (R) -mandelic acid.