Computer-assisted discovery of novel amino acid derived sulfides for enantioselective epoxidation of aldehydes

With the aid of molecular modeling, thiazolidine derivatives have been desi gned as catalysts for epoxidation of aldehydes. Accessible from amino acids , the thiazolidine derivatives can be synthesized in both enantiomeric form s and with a diverse array of substituents. A representative member, (S)-N- tert-butoxycarbonyl-2,2-dimethyl-4- isopropyl thiazolidine, of the thiazoli dine family has been prepared, and it has been shown to catalyze the format ion of trans-stilbene oxide with high enantioselectivity. Experimental and theoretical characterization has allowed the evaluation of the factors affe cting enantioselectivity, facilitating the design of second-generation thia zolidines and other chiral sulfides as epoxidation catalysts. (C) 2001 Else vier Science Ltd. All rights reserved.