Energetics of key Au(III)-substrate adducts relevant to catalytic hydroarylation of alkynes
Matthieu Regnacq1, Denis Lesage1, Marte S M Holmsen2,3,4
1Institut Parisien de Chimie Moléculaire - IPCM UMR 8232, CNRS/Sorbonne Université, 75252 Paris Cedex 05, France. yves.gimbert@univ-grenoble-alpes.fr.
Abstract:
(P,C)-cyclometalated Au(III) complexes have shown remarkable ability to catalyze the intermolecular hydroarylation of alkynes. Evidence of an outer-sphere mechanism has been provided in a previous study and is confirmed here by analysing the experimental data and DFT calculations. In this work, we propose evaluation of critical energies of dissociation of Au(III) complexes with different substrates via energy-resolved mass spectrometry (ERMS) experiments and kinetic modelling. The kinetic model is based on a multi-collisional approach. On the one hand, the classification confirms the mechanism previously proposed; on the other hand, it supports the collisional model and its application to particularly fragile adducts.
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