Direct Evidence for Intermolecular Oxidative Addition of σ(Si-Si) Bonds to Gold

Oxidative addition plays a major role in transitionmetal catalysis, but this elementary step remains very elusive in gold chemistry. It is now revealed that in the presence of GaCl3, phosphine gold chlorides promote the oxidative addition of disilanes at low temperature. The ensuing bis(silyl) gold(III) complexes were characterized by quantitative P-31 and Si-29 NMR spectroscopy. Their structures (distorted Y shape) and the reaction profile of sigma(Si-Si) bond activation were analyzed by DFT calculations. These results provide evidence for the intermolecular oxidative addition of sigma(Si-Si) bonds to gold and open promising perspectives for the development of new gold-catalyzed redox transformations.