BETA-TRIALKYLSILYL-BETA,GAMMA-UNSATURATED ALDEHYDE AND PREPARATION THEREOF

摘要

NEW MATERIAL:A compound expressed by formula I (R1 is H or lower alkyl; R2 and R3 are lower alkyl). EXAMPLE:2-Methyl-3-trimethylsilyl-3-octenal. USE:An intermediate for synthesizing stereoselectively various erythro and threo alcohols. PREPARATION:For example, an epoxy compound expressed by formula II (R4 is a protecting group of the hydroxyl group) is condensed with a Grignard reagent expressed by formula III (X1 is halogen) preferably at 2:1-1:3 ratio between the former and the latter in a solvent, e.g. diethyl ether, to prepare a condensate expressed by formula IV, which is then hydrolyzed in the presence of an acid substance, e.g. dichloroacetic acid, to remove the protecting group therefrom. The resultant diol expressed by formula V is then oxidized with periodic acid.