silylenes
Silylenes are silicon-centered species featuring a two-coordinate silicon atom with two substituents and a formal Si(II) oxidation state. They are the silicon analogs of carbenes and possess a lone pair on silicon along with a vacant p orbital, giving rise to unusual reactivity and high sensitivity to air and moisture. In contrast to more common silanes, silylenes are divalent and often exist only as transient intermediates, though stabilized variants can be isolated under carefully controlled conditions.
The electronic structure of silylenes can accommodate both singlet and triplet states. The relative energies of
Synthesis and stabilization typically rely on generating the Si(II) center from precursors by photolysis or thermolysis,
Reactions of silylenes include additions to multiple bonds and insertions into Si–H and C–H bonds, as well