A Biomimetic Model for the Active Site of [Fe]‑H₂ase Featuring a 2‑Methoxy-3,5-dimethyl-4-phosphato-6-acylmethylpyridine Ligand

Herein, we report the first 3,5-dimethyl-4-phosphatopyridine moiety containing [Fe]-H₂ase model, [2-MeO-3,5-Me₂-4-OPO­(OPh)₂-6-COCH₂C₅N]­Fe­(CO)₂(η²-6-Me-2-SC₅H₃N) (7), prepared by a multistep synthetic method including seven separate reaction steps. The first three reaction steps are utilized to prepare the organic precursors 4-TBSO-3,5,6-trimethyl-2-pyridone (1), 2-methoxy-4-TBSO-3,5,6-trimethylpyridine (2), and 2-methoxy-4-TBSO-3,5-dimethyl-6-chloromethylpyridine (3). The next three reaction steps are used to prepare the organometallic precursors (2-MeO-4-TBSO-3,5-Me₂-6-COCH₂C₅N)­Fe­(CO)₃I (4), (2-MeO-4-TBSO-3,5-Me₂-6-COCH₂C₅N)­Fe­(CO)₂(η²-6-Me-2-SC₅H₃N) (5), and (2-MeO-4-HO-3,5-Me₂-6-COCH₂C₅N)­Fe­(CO)₂(η²-6-Me-2-SC₅H₃N) (6). The final step is employed to prepare target model 7 by an esterification reaction of 6 with OP­(OPh)₂Cl in the presence of Et₃N. All of the prepared organic and organometallic compounds are new and have been characterized by elemental analysis and spectroscopy and, for some of them, by X-ray crystallography.