Olefin metathesis is an important reaction of organic usually catalyzed by metal-carbene
complexes of Mo and Ru. Nowadays catalysts of 3d metals have received considerable attention since
these metals are abundant, cheap, and show low toxicity. Recently vanadium-carbene complexes with
analogous ligands to those of the Schrock carbenes have been reported as successful catalysts for
the ROMP reaction of norbornene. In this work, we use DFT calculations to understand the reaction
mechanism and the energetic performance of the V(CHSiMe3)(N-2,6-C6H6)[OC(CF3)3](PMe3)2 (VC)
complex in catalyzing the reaction of ROMP of norbornene. It was observed that the reaction takes place in
the singlet spin surface by means of the classical olefin metathesis mechanism. The deactivation pathways
towards cyclopropanations were considered and showed higher barriers than those for olefin metathesis.
The replacement of the carbene substituent SiMe3 the substituent CMe3 was also analyzed, showing no
considerable differences regarding the previous catalysts. The activity of the VC catalyst compared to the
Schrock carbenes showed that the classical catalyst has smaller barriers than the vanadium catalysts.