Disilenyl Silylene Reactivity of a Cyclotrisilene

Abstract

The highly reactive silicon congeners of cyclopropene, cyclotrisilenes (c-Si3R4), typically undergo either paddition to the Si=Si double bond or s-insertion into the Si@ Si single bond. In contrast, treatment of c-Si3Tip4 (Tip = 2,4,6- iPr3C6H2 ) with styrene and benzil results in ring opening of the three-membered ring to formally yield the [1+2]- and [1+4] cycloaddition product of the isomeric disilenyl silylene to the C=C bond and the 1,2-diketone p system, respectively. At elevated temperature, styrene is released from the [1+2]- addition product leading to the thermodynamically favored housane species after [2+2] cycloaddition of styrene and cSi3Tip4.