Synthesis and reactivity of functional 1-methyl-silacyclopentenes

The silylenes MeSiCl, MeSiOMe and MeSiNMe2 can be thermally generated from disilanes and trapped by butadiene, isoprene and 2,3-dimethylbutadiene to give functionally-substituted silacyclopentenes. Some examples of cycloadditions to heterodienes are included to demonstrate the scope and mechanism of the reaction. The reactivity of 1-chloro-1-methyl-silacyclopent- 3-ene has been studied.