Abstract Silacyclopentadienylmethylene generated from thermolysis and photolysis of 1- methyl-2, 3, 4, 5-tetraphenylsilacyclopentadienyl-diazomethane and-diazirine rearranges to silabenzene by ring expansion and to 5-silafulvene by 1, 2-migration of a methyl group. These intermediates were successfully trapped by alcohols, diene, and ketone.
