DOI: 10.1002/ejic.201800251 "Historical Overview of N-Heterocyclic Carbenes in Alkene Metathesis." Slugovc, C. 10.1021/acs.organomet.5b00715 "Consequences of the Electronic Tuning of Latent Ruthenium-Based Olefin Metathesis Catalysts on Their Reactivity." Żukowska, K.; Pump, E.; Pazio, A.
DOI: 10.3762/bjoc.12.17 "Variation of the Sterical Properties of the N-Heterocyclic Carbene Coligand in Thermally Triggerable Ruthenium-Based Olefin Metathesis Precatalysts/Initiators." Pump, E.; Leitgeb, A.; Kozłowska, A.; Torvisco, A.; Falivene, L.; Cavallo, L.; Grela, K.; Slugovc, C. DOI: 10.3762/bjoc.11.158 "Mechanism of the Ru-Allenylidene to Ru-Indenylidene Rearrangement in Ruthenium Precatalysts for Olefin Metathesis." Pump, E.; Slugovc, C.; Cavallo, L.; Poater, A. DOI: 10.1002/9783527674107.ch27 "Thermal effects in polymerisations – a live view differentiating between bulk effects, thermal diffusion, and oxygen inhibition” Geier, R.; Wappl, C.; Freiszmuth, H.; Slugovc, C.; Gescheidt, G.
This mechanism is called the Chauvin mechanism, after its first proponent, Yves Chauvin of the French Petroleum Institute.
Chauvin's proposal of this mechanism shortly after the discovery of metal alkylidenes by Dick Schrock at Du Pont earned him a Nobel Prize in 2005.
In particular, terminal olefins (with the double bond at the end of the chain) are converted into internal olefins (with the double bond somewhere in the middle of the chain). The surface of the metal oxides may be covered with a mixture of hydroxyl groups as well as terminal oxides (M=O groups).
The terminal oxides on the surface are the important part of the catalyst.
Olefin metathesis, or alkene metathesis, is an important process in petroleum refining and in the synthesis of important compounds such as pharmaceuticals.
The mechanism of olefin metathesis is related to pericyclic reactions like Diels Alder and [2 2] reactions.
In most cases, a [2 2] addition won't work unless photochemistry is involved, but it does work with metal alkylidenes.
The reason for this exception is thought to involve the nature of the metal-carbon double bond.