DUGi

A comprehensive study of olefin metathesis catalyzed by Ru-based catalysts

http://dugi.udg.edu/item/http:@@@@hdl.handle.net@@2072@@268704

During a Ru-catalyzed reaction of an olefin with an alkylidene moiety that leads to a metallacycle intermediate, the cis insertion ofthe olefin can occur from two different directions, namely side and bottom with respect to the phosphine or N-heterocyclic ligand(NHC), depending on the first or second generation Grubbs catalyst. Here, DFT calculations unravel to which extent the bottomcoordination of olefins with respect is favored over the side coordination through screening a wide range of catalysts, including firstand second generation Grubbs catalysts as well as the subsequent Hoveyda derivatives. The equilibrium between bottom and sidecoordination is influenced by sterics, electronics, and polarity of the solvent. The side attack is favored for sterically less demandingNHC and/or alkylidene ligands. Moreover the generation of a 14-electron species is also discussed, with either pyridine or phosphineligands to dissociate

A.P. thanks the Spanish MINECO for a project CTQ2014-59832-JIN, and European Commission for a Career Integration Grant (CIG09-GA-2011-293900)

Beilstein-Institut