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Alkyne metathesis is an organic reaction involving the redistribution of alkyne chemical bonds. This reaction is closely related to olefin metathesis. Metal-catalyzed alkyne metathesis was first described in 1968 by Bailey, et al. The Bailey system utilized a mixture of tungsten and silicon oxides at temperatures as high as 450 °C. In 1974 Mortreux reported the use of a homogeneous catalyst—molybdenum hexacarbonyl at 160 °C—to observe an alkyne scrambling phenomenon, in which an unsymmetrical alkyne equilibrates with its two symmetrical derivatives. ==History== The Mortreux system consists of the molybdenum catalyst molybdenum hexacarbonyl Mo(CO)6 and resorcinol cocatalyst. In 1975 T.J. Katz proposed a metal carbyne and a metallacyclobutadiene as an intermediate and in 1981 R.R. Schrock characterized several metallacyclobutadiene complexes that were catalytically active. : The Schrock catalyst system tris(''t''-butoxy)(2,2-dimethylpropylidyne)tungsten(VI) is unreactive towards alkenes. On the other hand Fischer carbenes have no value in alkyne or alkene metathesis. : The Schrock catalyst is commercially available and is prepared by amidation of tungsten tetrachloride with lithium dimethylamide to a W2(NMe2)6 which undergoes alcoholysis by tert-butoxy groups with ''tert''-butanol. : This alkylidyne complex undergoes a metathesis with neoheptyne to give the final product. In 2001, Fürstner reported a new molybdenum catalyst replacing alkoxide with aniline ligands. : 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「Alkyne metathesis」の詳細全文を読む スポンサード リンク
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