English: 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 Montreux reported the use of a homogeneous catalyst—molybdenum hexacarbonyl at 160 °C--to observe an alkyne scrambling phenomenon, in which an unsymmetric alkyne equilibrates with its two symmetrical derivative.