Spectroscopic characterization of a Ru(III)-OCl intermediate: a structural mimic of haloperoxidase enzymes.

Haloperoxidase enzymes utilize metal hypohalite species to halogenate aliphatic and aromatic C-H bonds to C-X (X = Cl, Br, I) in nature. In this work, we report the synthesis and spectroscopic characterization of a unique Ru III -OCl species as a structural mimic of haloperoxidase enzymes. The reaction of [(BnTPEN)Ru II (NCCH 3 )] 2+ (BnTPEN = N 1 -benzyl- N 1 , N 2 , N 2 -tris(pyridine-2-ylmethyl)ethane-1,2-diamine) with hypochlorite in the presence of an acid in CH 3 CN : H 2 O mixtures generated a novel [(BnTPEN)Ru III -OCl] 2+ species that persists for 4.5 h at room temperature. This new species was characterized by UV-vis absorption, EPR, and resonance Raman spectroscopic techniques, and ESI-MS. The Ru III -OCl species is capable of performing oxygen atom transfer and hydrogen atom abstraction to various organic substrates.