Phospho-Aldol Catalysis via Chiral Schiff Base Complexes of

Organometallics 2000, 19, 4445-4457

4445

Phospho-Aldol Catalysis via Chiral Schiff Base Complexes of Aluminum† Julian P. Duxbury, Justin N. D. Warne, Rashfeena Mushtaq, Caroline Ward, Mark Thornton-Pett, Mingliang Jiang, Robert Greatrex, and Terence P. Kee* School of Chemistry, University of Leeds, Leeds LS2 9JT, U.K. Received May 5, 2000

Chiral complexes of aluminum containing the salcyen ligand framework, [(R,R)-salcyen]AlX (X ) Me, OSiMe2tBu), catalyze the asymmetric addition of diorgano-H-phosphonates to carbonyls: the phospho-aldol reaction. Reaction proceeds smoothly at ambient temperature in various solvents and under aerobic conditions, to afford R-hydroxyphosphonate esters (MeO)2P(O)CHR(OH), with enantiomeric excesses (ee’s)