Reactions of an Isolable Dialkylsilylene with Ketones

The reactions of isolable dialkylsilylene 2,2,5,5-tetrakis(trimethylsilyl)-1-silacyclopentane-1,1-diyl
with different types of ketones such as adamantanone, acetone, benzophenone,
and cyclopropenones proceed smoothly at room temperature to afford
the corresponding siloxirane, silyl enol ether, 2-oxa-silacyclopentene,
and unusual cyclopropenylsilanes, respectively, without formation
of any secondary or side-reaction products. The electronic structure
of various types of model carbonyl silaylides was investigated using
DFT calculations. The diversity of the reaction modes is explained
by invoking the substituent effects on the electronic nature of the
initially formed carbonyl silaylides.