Applied Catalysis A: General, Vol.375, No.2, 247-251, 2010
Enantioselective addition of diethylzinc to aldehydes catalyzed by D-glucosamine derivatives: Highly pronounced effect of trifluoromethylsulfonamide
We present the synthesis of beta-hydroxy sulfonamides derived from D-glucosamine and their application as ligands in titanium tetraisopropoxide promoted enantioselective addition of diethylzinc to benzaldehyde and selected aromatic and aliphatic aldehydes. The N-trifluoromethylosulfonamido-D-glucosamine derivative is one of the most active ligands known and only 1 mol% of the ligand is sufficient for efficient catalysis of diethylzinc addition. The reaction is highly enantioselective for some aromatic aldehydes and enantiomeric excess up to 99% was obtained. (C) 2010 Elsevier B.V. All rights reserved.
Keywords:D-Glucosamine;Diethylzinc;Titanium tetraisopropoxide;Enantioselective;Trifluoromethylsulfonamide