Dioxygen Activation by Gold(I)-Distorted Porphyrin Dinuclear Complexes.

Interactions between gold-based materials and dioxygen (O 2 ) have motivated researchers to understand reaction mechanisms for O 2 activation by homo- and heterogeneous gold catalysts. In this work, gold(I) porphyrin dinuclear complexes were synthesized with a saddle-distorted porphyrin ligand. The gold(I) porphyrin complexes showed unprecedented O 2 activation in the presence of protic solvents to form gold(III) tetradentate porphyrin complexes. Mechanistic insights into the O 2 activation by the gold(I) center were elucidated by spectroscopic measurements and theoretical calculations, revealing that dissociation of halides on the gold(I) center by alcohol solvents and hydrogen bonding of an N-H proton in the distorted porphyrin with dioxygen played important roles in establishing the unique reactivities of gold(I) complexes.