The recognition of a new pathway for the reaction of molecular oxygen with a Pd(II)-hydride to produce a Pd(II)-hydroperoxide

A DFT study of the mechanistic details of the insertion of molecular oxygen into the palladium(II) hydride bond of trans-[PdH(O2Ac)(IMes)2] complex to form the Pd(II)-hydroperoxide was carried out. Results show that the involved singlet and triplet stationary points are different. Particularly, before the formation of a stable singlet intermediate the hopping from triplet to singlet surface occurs. Rearrangement of this intermediate structure through a low lying transition state gives formation of the final hydroperoxo complex.