A comparative study of reactivity and selectivity of chiral diamines and structurally analogous amino alcohol ligands in enantioselective alkylations with diethylzinc

Abstract

A series of chiral delta-diamines and structurally analogous delta-amino alcohols derived from natural tartaric acid were synthesized and a comparative study of their activity and selectivity in the enantioselective alkylation of aromatic aldehydes was carried out. Our results show that in general the delta-diamines were found to be better chiral inducers than the corresponding delta-amino alcohols. The highest selectivity was observed when benzaldehyde was alkylated in the presence of the benzylic diamine, giving (R)-1-phenylpropanol with an ee of 42%. Copyright © 2008 John Wiley & Sons, Ltd.