Scandium trisdodecylsulfate (STDS). A new type of Lewis acid that forms stable dispersion systems with organic substrates in water and accelerates aldol reactions much faster in water than in organic solvents

A new type of Lewis acid, scandium trisdodecylsulfate (STDS), was prepared. In the presence of a catalytic amount of STDS, aldol reactions of silyl enol ethers with aldehydes proceeded smoothly in wafer without using any organic solvents. It was proven that stable dispersion systems including the catalyst and organic substrates were formed in water and that catalytic activity in water was much higher than that in organic solvents. As far as we know, this is the first example of Lewis acid catalysis in stable dispersion system in water. (C) 1998 Elsevier Science Ltd. All rights reserved.