Stereoselective Synthesis of 1,2,3-Triol Derivatives from α,β-Unsaturated Acylsilanes

The stereoselective synthesis of 1,2,3-triol derivatives having contiguous stereogenic centers from alpha,beta-unsaturated acylsilanes 1 was described. The oxidation of an olefin moiety of 1 with osmium tetroxide proceeded smoothly to give the corresponding 2,3-syn-dihydroxyacylsilanes 2. The protection of two hydroxy groups of 2 followed by a nucleophilic reaction to the silyl carbonyl group gave the corresponding silylated triol derivatives (7 and 8) with high stereoselectivity, depending on the kind of nucleophilic reagents. The deprotection for 7 and 8 and the following protodesilylation gave two isomers of possible four 1,2,3-triol derivatives. The stereoselective triol synthesis by asymmetric diolization of alpha-silylated allyl alcohols 11 derived by nucleophilic addition to 1 was also investigated. (C) 2014 Wiley Periodicals, Inc.