Dimethylsilanethione - Generation by retro-ene reaction and cycloaddition with ketene

Article abstract of DOI:10.1016/0040-4039(96)01532-8

Dimethylsilanethione was cleanly generated, under flash vacuum thermolysis conditions, by retro-ene cleavage of propargylthiodimethylsilane. The cothermolysis of this latter and ketene dimer led in 60% yield to an only [2 + 2] cycloadduct, 2,2-dimethyl-4-methylene-2-sila-3-thiaoxetane, which in turn can be cleaved at higher temperature to give hexamethylcyclotrisiloxane.