In his recent review of the chemistry of silacyclopropanes,'Seyferth noted the many attempts which preceded his first successful synthesis of 1972.2 There are no recorded failures in the synthesis of silacyclopropenes, for, with the notable exception discussed below, the idea that a silacyclopropene might prove to be stable did not dawn on the chemical world until Seyferth uncovered the unexpected stability of the saturated compound.
