1,1-Dimethyl-1-silacyclohexan-4-one and Its Germanium Analogue via Boracyclic Intermediates

Article abstract of DOI:10.1021/jo00188a010

The hydroboration of divinyldimethylsilane (3) was examined by using representative hydroborating agents with the finding that 9-borabicyclo<3.3.1>nonane (9-BBN) gives a single 1,5-diboryl adduct.An exchange reaction of this adduct with borane-methyl sulfide complex (BMS) gives, after methanolysis, the corresponding B-methoxy-4-silaborinane product (10) isomerically pure in 80percent isolated yield.Several reactions of this silaboracycle are investigated including its conversion to 1,1-dimethyl-1-silacyclohexan-4-one (1) in 67percent isolated yield.A related method is reported for the preparation of the corresponding germanium compound (22).Spectroscopic data for these heterocyclic derivatives are presented.