Hydrogen Loss from the Shvo Catalyst

At high temperatures in toluene-d₈, the ruthenium hydride monomer has been observed to lose hydrogen to reform an unsaturated species which is trapped by another hydride compound. We are studying the kinetics of this process, trapping the unsaturated species with PPh₃. We have also observed acceleration of hydrogen loss in the presence of alcohol or water, presumably due to a hydrogen bonded bridge via the protic solvent, which provides a lower energy pathway for H₂ loss and hydrogen exchange.