Mechanistically guided development of homogenous nickel catalysis through rapid computational catalyst screening

Abstract

Advances in understanding the mechanisms of homogeneous nickel catalysis has led to a remarkable progress in this field. However, the discovery of active catalysts is still largely based on trial and error, and the catalysts are mostly based on chelating (nitrogen) ligands. We report a combined theoretical and experimental study of nickel-catalyzed hydroarylation of vinylarenes, where experimental advances were complemented with a rapid computation catalyst screening. Once the mechanism is known and preliminary experimental data is available, the screening approach can predict other suitable ligands by assessing the electronic structure of the catalyst complex without the computationally intensive determination of the transition states. Using the approach described, we developed the reaction that proceeds under unusually mild conditions and is broadly applicable on a range of vinylarenes and (het)aryl halides, including previously inaccessible chlorides. The reaction was found to be highly dependent on the choice of ligand, with monodentate PPh3 proving optimal. Extensive quantum chemical simulations elucidated the reaction mechanism and identified Ni(PPh3)xClyH as the crucial active species.