New chiral catalysts for phospho-transfer

Chiral salcyan complexes of aluminium are effective air and water tolerant enantioselective catalysts for the hydrophosphonylation of carbonyls. Complexes of the form [(R,R)-salcyan]AlX (X = OH, OR) result in product enantioselectivity changes (Delta ee) of ca. 100% compared to those returned in the presence of related complexes [(R,X)-salcyen]AlX even though they both possess a chiral ligand framework with the same absolute stercochemistry. (C) 2000 Elsevier Science Ltd. All rights reserved.