Abstract
A theoretical study of a double activation mechanism that deactivates a family of second-generation Ru-based catalysts is presented. DFT calculations are used to rationalize the complex mechanistic pathway from the starting precatalyst to the experimentally characterized decomposition products. We thoroughly study all intermediates proposed by Grubbs and co-workers, characterizing them with different computational tools as aromaticity and Mayer Bond Order. In particular, we show that all the intermediates proposed by Grubbs and co-workers are indeed possible intermediates of the deactivation pathway, although the sequence of steps is somewhat different. Finally, we reveal why free PCy3 is fundamental to shift the equilibrium towards double C-H activation. (C) 2010 Elsevier B.V. All rights reserved.