1,2-cycloaddition reactions of dihalocarbenes (:CCl2, :CBr2, CF3 CCl) to some pi-bonded organosilanes under phase transfer catalytic conditions

The dihalocarbenes of the type :CXY (X = Y = Br, Cl; X not equal Y = CF3, Cl) have been generated by the reaction of the corresponding haloform and aqueous potassium hydroxide solution in the presence of phase transfer catalysts like 18-Crown-6 and Cetrimide(R). 1,2-Cycloaddition reactions of the carbenes have been carried outwith tetraorganosilanes having one or two allyl or vinyl groups, where the addition of carbenes takes place easily on both the allyl functionalities irrespective of the methyl or phenyl groups attached with silicon. Whereas in the case of vinylsilanes, similar addition reactions are found to be partial.