Tetrahydroisoquinoline-Based N-Oxides as Chiral Organocatalysts for the Asymmetric Allylation of Aldehydes

The short synthesis of a series of novel chiral N-oxideorganocatalysts and their evaluation in the asymmetric allylation reaction of aromatic and a-beta-unsaturated aldehydes with allyltrichlorosilane is reported. These readily modifiable organocatalysts are the first of their kind based on the tetrahydroisoquinoline framework. The chiral homoallyl products were obtained with good chemical efficiency (up to 93% yield) and high enantioselectivity (up to 91%ee) under mild reaction conditions (23 degrees C).