Preparation of 3-Methylenesilacyclobutane and Its Use in Organic Synthesis.

Abstract Treatment of 3-methylene-1,1-diphenylsilacyclobutane ( 1a ) with dihalo-melhyllithium provided ring expanded 2-halo-4-methylenesilacyclopentane. Heating a mixture of 1a and carbonyl compound such as PhCHO or PhCOMe at reflux in 1,2-dichloroethane afforded 5 methylene 1,1 diphenyl-2-oxa-1-silacyclohexane which was converted into 3-methylene-1,5-alkanediol monomethyl ether upon treatment with dimethyl acelal in the presence of Lewis acid catalyst. Treatment of ketoaldehyde (PhCOCH 2 CHO) with 1a under BF 3 · OEt 2 catalysis gave 3-methylene-1-phenyl-8 oxabicyclo[3.2.1]octane in one pot