Performance of density functional theory on homogeneous gold catalysis

The performance of 32 density functionals to describe the homogeneous gold catalysis of propargyl esters has been tested. These catalytic reactions are very commonly rather complex, numerous intermediates can be found along the reaction profile and the individual reaction steps are often associated to very small barrier heights. In this scenario, the experimental kinetic study of the catalytic mechanisms is very challenging. A computational approach to this problem provides invaluable help to gain insight into these mechanisms. However the high accuracy needed to describe such highly branched paths with low energy transition states poses many practical problems for cost-efficient DFT methods. The lack of accurate experimental or high-level computational data to employ as validation sets for these methods is also an added difficulty. High-level computational data needed to validate these functionals have been obtained at the CCSD/def2-TZVPP//CCSD/def2-SVP level and, with such data, we aim to help discern the best density functional recipe for homogeneous gold catalysis.