Metathesis case studies

Case Study Developing a Ruthenium-Carbene Catalyst for Acrylonitrile Metathesis... 

The most plausible inference from these studies is to consider for the metathesis reaction a nonconcerted reaction mechanism involving a five-membered metallocyclic intermediate. In the case of the metathesis of propene, this can be visualized as follows ... 

Despite the numerous reports concerning NHC-Ru olefin metathesis initiators, a complex incorporating a carbene that has only one exocyclic substituent adjacent to the carbenic centre was not reported until 2008. Studies by Grubbs and co-workers led to the development of ruthenium-based catalysts bearing such carbene ligands, in this case incorporating thiazole-2-ylidenes [63] (Fig. 3.19). 

---