DFT calculations have been used to determine the thermodynamic and kinetic preference for ruthenacyclobutanes resulting from the experimentally proposed interconversion pathways (olefin and alkylidene rotations) through the investigation of cross-metathesis reaction mechanism for neutral Grubbs catalyst, RuCl2(=CHEt)NHC (A), with ethylene and 1-butene as the substrates. Our results show that although the proposed interconversions are feasible due to the predicted low energy barriers (2-6 kcal/mol), the formation of ruthenacyclobutane is kinetically favored over the competitive reactions involving alkylidene rotations. In comparison with catalyst A, the reaction energy profile for cationic Piers catalyst [RuCl2(=CHPCy3)NHC+] (B) is more endothermic in nature with both ethylene and 1-butene substrates.
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledgements: A.P. thanks the Spanish MINECO for a Ramon y Cajal contract (RYC-2009-05226) and a Jose Castillejo fellowship (CAS14/00165), and European Commission for a Career Integration Grant (CIG09-GA-2011-293900).
ASJC Scopus subject areas
- Physical and Theoretical Chemistry