Diironhexacarbonyl clusters with imide and amine ligands: hydrogen evolution catalysts

The reaction of Fe₃(CO)₁₂ and N-(4-thiolphenyl)-1,8-naphthalimide afforded a new diironhexacarbonyl complex (3). The integrity and electronic structure of 3 has been determined by elemental analysis and spectroscopy (NMR and infrared). Infrared spectrum of 3 shows peaks at 2000, 2040, and 2075?cm^?1 ascribed to stretching frequencies of the terminal metal carbonyls. Compound 4 was obtained from the reaction of Fe₃(CO)₁₂ and 4-aminothiolphenol. A comparison of the electronic, electrochemical, and electrocatalytic properties of 3 and 4 are discussed. Cyclic voltammetric studies show that 3 and 4 catalyze the reduction of acetic acid to produce hydrogen at ?2.19?V and ?1.88?V versus Fc/Fc⁺, respectively.