A Tetranuclear Propane-1,3-Dithiolate Complex, [Fe2(CO)5{Ph2P(CH2)3} {(μ-SCH2)2CH2}]2, with a Bridging 1,6-Bis(diphenylphosphino)hexane Ligand

The 2:1 molar reaction of [Fe-2(CO)(6){(mu-SCH2)(2)CH2}] (1) and a bidentate diphosphine ligand, 1,6-bis(diphenylphosphino) hexane (dpph), in the presence of Me3NO resulted in the isolation of [Fe-2(CO)(5){Ph2P(CH2)(3)}{(mu-SCH2)(2)CH2}](2) (2) as red crystals in 71 % yield. The dpph ligand in compound 2, coordinates two Fe2S2 subunits as bridging mode and hence makes a linkage between two [Fe-2(CO)(5){(mu-SCH2)(2)CH2}] fragments. Each Fe2S2 butterfly of the complex consists of two fused Fe(SC-C-C-S) six-membered rings, one of which attains a chair conformation, and the other is necessarily in a boat conformation. Compound 2 has unequivocally been characterized by elemental analysis, IR, H-1 NMR and P-31 NMR spectroscopy together with single crystal X-ray diffraction studies. Crystals of 2 are triclinic, space group P-1, a = 9.918(4) angstrom, b = 10.347(3) angstrom, c = 14.581(5) angstrom, alpha =72.239(12)degrees, beta = 80.342(12)degrees, gamma = 68.550(14)degrees and Z = 1. [GRAPHICS] .