Transition metal reactions of silanes II. The reaction of cycloalkenes with various hydrosilanes and carbon monoxide catalyzed by Co2(CO)8

The reaction of cycloalkenes(cyclopentene, cyclohexene, cycloheptene, cyclooctene, 1-methylcyclohexene, and norbornene) with Et₂MeSiH and carbon monoxide in the presence of Co₂(CO)₈ gave the corresponding diethylmethylsiloxymethylenecycloalkenes. In such reactions of cyclohexene, the following hydrosilanes gave the corresponding siloxymethylenecyclohexanes: Me₃SiH, EtMe₂SiH, Et₂MeSiH, Et₃SiH, PhMe₂SiH, Ph₂MeSiH. Effects of the reaction conditions(the pressure of carbon monoxide, the temperature, and the molar ratio of cyclohexene to Et₂MeSiH) were examined. The yield of diethylmethylsiloxymethylenecyclohexane increased remarkably with increasing molar ratio of cyclohexene to Et₂MeSiH. At higher temperature, the yield of the isomerization product, 1-(diethylmethylsiloxymethyl)-cyclohex-1-ene, increased.