Volcano Plots of Reaction Yields in Cross-Coupling Catalysis

It is critical to identify the influence of phosphine ligands on cross-coupling reactions to obtain a higher yield. In order to reveal ligands' effects, many descriptors have been proposed, which allow statistical analysis to be implemented in mining the structure-property relationship and providing mechanistic insights. This work combines the steric and electronic effects into a descriptor, %V_bur (min) - 3·HOMO-LUMO gap (eV) where %V_bur (min) is the minimum percent buried volume and the Boltzmann averaged gap is used. Volcano plots were well presented by yields (y-axis) and the descriptor (x-axis) for Ni- and Pd-catalyzed cross-coupling reactions. In addition, volcano peaks in these plots can be located to optimize reaction yields for experiments. Our work sheds light on the reaction mechanisms of phosphine ligands and delivers a strategy for choosing ligands in cross-coupling catalysis.