Novel Catalyst for Enantioselective Allylboration of Aldehydes

Conventional techniques for the allylation of aldehydes typically require the use of toxic or unstable reagents and require high catalyst loading (e.g. 20 mol%). For example, Brown allylation requires two molar equivalents of a chiral inductor. As a result, industry is seeking alternative methods of aldehyde allylation.

University of Alberta researchers have developed a second generation chiral Bronsted acid catalyst that provides 94-96% enantiomeric excess for many aldehydes at a catalyst loading as low as 2 mol%. The results obtained with the new catalyst are significantly better than the first generation catalyst reported in Angewandte Chemie Int. Ed. 2006, 45, 2426-2428.

• High enantioselectivity and high yields.
• Non-toxic.
• Simple and convenient reaction procedure.
• Requires only a small (catalytic) amount of the chiral inductor.
• Employs a stable commercial reagent.
• Novel diol catalyst is recoverable.
• Low cost of production.