Enantioselective Silylcyanation of Aldehydes and Ketones by a Titanium Catalyst Prepared from a Partially Hydrolyzed Titanium Alkoxide and a Schiff Base Ligand

✍ Scribed by Kazuhiko Yoshinaga; Takushi Nagata

• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 148 KB
• Volume: 351
• Category: Article
• ISSN: 1615-4150
• DOI: 10.1002/adsc.200900207

✦ Synopsis

Abstract

In the presence of small amount (0.2–1.0 mol%) of a titanium complex catalyst prepared from a partially hydrolyzed titanium alkoxide and an optically active tridentate Schiff base ligand, the enantioselective silylcyanation of aldehydes and ketones proceeded in a short reaction time at room temperature to afford the corresponding optically active cyanohydrin derivatives in excellent chemical yield with high enantiomeric excess (86–97% ee). The results indicate that partially hydrolyzed titanium alkoxides are a promising titanium source for the preparation of efficient catalysts for asymmetric synthesis.