Synthesis and stereoselective aldol reaction of dihydroxyacetone derivatives

Efficient synthetic methods for 1,3-di-O-benzyldihydroxyacetone (3) and 1,3-O-cyclohexylidenedihydroxyacetone (8) were developed. TiCl4-mediated aldol reaction of the silyl enol ether of 3 with aldehydes gave syn aldol products while the reaction of the silyl enol ether of 8 with aldehydes afforded anti aldol products.