LAUSR

As the [2Fe]H subsite models of [FeFe]-hydrogenases, a series of PNP-chelated and -bridged diiron dithiolate complexes 1a–f and 2a–f together with the three related monophosphine complexes 3a–c were prepared by the selective substitutions of the all-carbonyl complex Fe2(μ-pdt)(CO)6 (A, pdt = SCH2CH2CH2S) with aminodiphosphines (Ph2P)2NR (denoted as PNP) under different reaction conditions. The first UV irradiation of the toluene solutions of A with different PNP ligands (PNP = (Ph2P)2NR; R = (CH2)3Me, (CH2)3NMe2, (CH2)3Si(OEt)3, C6H5, C6H4OMe-p, C6H4CO2Me-p) readily afforded the target PNP-chelated complexes Fe2(μ-pdt)(CO)4{(κ2-Ph2P)2NR} (1a–f), while the reflux of xylene solutions of A with the aforementioned PNP ligands produced the PNP-bridged complexes Fe2(μ-pdt)(CO)4{(μ-Ph2P)2NR} (2a–f). Comparatively, treatments of A and one type of PNP ligand with N-aryl substituents R (R = C6H5, C6H4OMe-p, C6H4CO2Me-p) in MeCN at room temperature in the presence of the decarbonylating agent Me3NO·2H2O formed the u...