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|Section2= }} Silylenes are chemical compounds containing a divalent silicon atom without any electrical charge. Both dicoordinate and tricoordinate silylenes are reported in the literature. They are considered to be heavier analogues of carbene. In earlier times, they were called ''silene'', but this is a mistake, as that term means compounds of π-bonded silicon: Si=C. The generic term analogous to carbene is "silicene." Silylenes have been proposed as reactive intermediates and are so unstable that they usually cannot be isolated. While carbenes are observed in either the triplet or singlet state depending on the nature of the substituents, silylenes typically have a singlet ground state because the energy gap between the 3s and 3p orbitals of the silicon atom is very large and so the singlet-triplet gaps are enormous. ==History== The first experimental chemical observation of silylene as an intermediate was demonstrated by P.S. Skell and E.J. Goldstein in 1964. The first stable silylene was synthesized and isolated as a diamino silylene, ''N,N’''-di-''tert''-butyl-1,3-diaza-2-silacyclopent-4-en-2-ylidene, in 1994 by M. Denk et al.〔Denk, M., Green, J.C., Metzler, N., Wagner, M. (1994), ''Electronic structure of a stable silylene: photoelectron spectra and calculations''. Journal of the Chemical Society, Dalton Transactions, 2405–2410.〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Silylene」の詳細全文を読む スポンサード リンク
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