| Abstract: | The two‐step one‐pot oxidative decarbonylation of [Fe2(S2C2H4)(CO)4(PMe3)2] ( 1 ) with [FeCp2]PF6, followed by addition of phosphane ligands, led to a series of diferrous dithiolato carbonyls 2 – 6 , containing three or four phosphane ligands. In situ measurements indicate efficient formation of 1 2+ as the initial intermediate of the oxidation of 1 , even when a deficiency of the oxidant was employed. Subsequent addition of PR3 gave rise to [Fe2(S2C2H4)(μ‐CO)(CO)3(PMe3)3]2+ ( 2 ) and [Fe2(S2C2H4)(μ‐CO)(CO)2(PMe3)2(PR3)2]2+ (R=Me 3 , OMe 4 ) as principal products. One terminal CO ligand in these complexes was readily substituted by MeCN, and [Fe2(S2C2H4)(μ‐CO)(CO)2(PMe3)3(MeCN)]2+ ( 5 ) and [Fe2(S2C2H4)(μ‐CO)(CO)(PMe3)4(MeCN)]2+ ( 6 ) were fully characterized. Relevant to the Hred state of the active site of Fe‐only hydrogenases, the unsymmetrical derivatives 5 and 6 feature a semibridging CO ligand trans to a labile coordination site. |
