Synthesis, structure and electrochemical properties of diiron S-(−)-1-Phenylethylazadithiolate complexes

Abstract

A novel diiron S-(−)-1-phenylethylazadithiolate complex, Fe2[(μ-SCH2)2NCH(CH3)Ph](CO)6 (1), has been prepared by the condensation of Fe2(μ-SH)2(CO)6, CH2O and S-(−)-1-phenylethylamine. Furthermore, the reaction of complex 1 and phosphine ligands (PPh3, P(C6H4-4-F)3, dppe) in the presence of the decarbonylation agent Me3NO·2H2O resulted in the formation of the phosphine-substituted diiron S-(−)-1-phenylethylazadithiolate complexes Fe2[(μ-SCH2)2NCH(CH3)Ph](CO)5(PPh3) (2), Fe2[(μ-SCH2)2NCH(CH3)Ph](CO)5[P(C6H4-4-F)3] (3) and {Fe2[(μ-SCH2)2NCH(CH3)Ph](CO)5}2(Ph2PCH2CH2PPh2) (4). Complexes 1–4 have been fully characterized by elemental analysis, FTIR and NMR (1H, 13C, 31P) spectroscopies, and for 1, 2 and 4 by X-ray crystallography. Moreover, complexes 1 and 2 were found to be catalysts for hydrogen production in the presence of acid under electrochemical conditions. According to the electrochemical observations, a possible catalytic mechanism for complexes 1 and 2 was proposed.