Phenyl-functionalized diiron propanedithiolato complexes with a chelated 1,2-bis(diphenylphosphino)benzene ligand

Reaction of 1,2-bis(diphenylphosphino)benzene (dppbz) with PhpdtFe₂(CO)₆ (A) in hot acetonitrile yielded a chelated complex, PhpdtFe₂(CO)₄(κ²-dppbz) (1), in moderate yield. Further treatment using an excess of HBF₄·Et₂O resulted in the protonation of 1 at room temperature in dichloromethane solution, forming a hydride [Phpdt(μ-H)Fe₂(CO)₄(κ²-dppbz)]BF₄ (2). The chemical structures of both complexes were fully characterized by spectroscopic methods and X-ray crystallography, and the electronic structures were further investigated by UV-vis spectroscopy. The cyclic voltammetry (CV) of 1 in the absence and presence of acetic acid were also investigated.