A Novel Acylmethylpyridinol Ligand Containing Dinuclear Iron Complex Closely Related to [Fe]-Hydrogenase

On synthesizing the PMB-protected mononuclear iron complexes [2-C­(O)­CH2-6-PMBOC5H3N]­Fe­(CO)3I (6) and [2-C­(O)­CH2-6-PMBOC5H3N]­Fe­(CO)2(2-SC5H4N) (7), the novel acylmethylpyridinol ligand containing dinuclear iron complex [2-C­(O)­CH2-6-HOC5H3N]­Fe2(CO)4[2′-C­(O)­CH2-6′-OC5H3N]­(2-SC5H4N) (9), which is closely related to the active site of [Fe]-hydrogenase, has been prepared unexpectedly via removal of the PMB protecting group from 7 under the action of excess trifluoroacetic acid. The [Fe]-hydrogenase-related complex 9 and its precursor complexes 6 and 7 have been fully characterized by elemental analysis, spectroscopy, and X-ray crystallography.