Siliconcarbon multiple-bonded (pπpπ)intermediates : II. Chemical reactivity and selectivity of thermally generated 1,1-dimethyl-1-silaethene (Me2SiCH2)

The order of reactivity and the selectivity of 1,1-dimethyl-1-silaethene (Me₂SiCH₂), generated from 1,1-dimethylsilacyclobutane at 611°, toward a variety of substrates was determined using standard competition experiments. The observed reactivity order was Ph₂CO>ROH, ArOH ? m-ClPhNH₂ CH₃CN, which indicates that with these substrates and under the reaction conditions used, Me₂SiCH₂ is behaving like an electrophilic species. Within a given class of substrates, polar effects were found to be generally unimportant, while increased steric effects caused a decrease in rate (up to 50%).