Amino alcohol-catalyzed asymmetric alkylation of benzaldehydes by dialkylzines can be achieved in supercritical fluoroform (scCH(3)) and supercritical ethane (SCC2H6) with high conversion and enantio selectivity. The higher enantioselectivity in ethane compared to CHF3 suggests that solvent polarity affects the reaction. The enantioselectivity in scCHF(3) is strongly pressure dependent. (C) 2002 Elsevier Science B.V. All rights reserved.