Nitrite reduction by copper through ligand-mediated proton and electron transfer.

Nitrite reduction by a copper complex featuring a proton-responsive tripodal ligand is demonstrated. Gaseous nitric oxide was confirmed as the sole NO by-product in quantitative yield. DFT calculations predict that nitrite reduction occurs a proton and electron transfer process mediated by the ligand. The reported mechanism parallels nitrite reduction by copper nitrite reductase.