Catalytic Hydrogen Generation from the Hydrolysis of Silanes by Ruthenium Complexes

Dimeric Ru(II) complexes Ru2(CO)4L2X4 (L = CO or PPh3; X = Cl or Br) have been found to catalyze the hydrolysis of silanes to produce hydrogen gas and silanols with turnover numbers in excess of 104 at room temperature. Deuteration and mass spectrometric studies have established that the hydrogen gas originates from one hydrogen atom from water and the other from silane. Ruthenium hydride intermediates have been detected in the NMR spectrum during the early stage of the reaction, while the FTIR spectra of more stable complexes such as Ru(CO)2(PPh3)(THF)Br2 and Ru(CO)2(PPh3)2(H)Br have been recorded upon completion of catalysis. A mechanism has been proposed to account for the ruthenium-catalyzed silane hydrolysis based on the experimental data.