Complete reversal of enantioselection using oxazoline-containing Schiff base ligands derived from L-serine in enantioselective addition of diketene to aldehydes

摘要

Starting from one stereogenic center (in this case from L-serine), we obtained two chiral Schiff bases possessing oxazoline moieties, each of which recognized a different enantioface of aldehydes with a high enantionteric excess [up to 93% ee (R) and 89% ee (S)] in the addition reaction of diketene to 2-furfural. (c) 2006 Elsevier Ltd. All rights reserved.