Synthesis, structures, and electrochemistry of diiron toluene-3,4-dithiolate complexes containing phosphine ligands

In this paper, four diiron toluene-3,4-dithiolate complexes with phosphine ligands were synthesized and characterized. Treatment of complex [Fe 2 (CO) 6 { μ -SC 6 H 3 (CH 3 )S}] ( 1 ) with the corresponding phosphine ligands ethyl diphenylphosphinite, 4-(dimethylamino)phenyldiphenylphosphine, 2-(diphenylphosphino)biphenyl, or vinyldiphenylphosphine in the presence of Me 3 NO·2H 2 O as the CO-oxidative agent afforded the products [Fe 2 (CO) 5 ( L ){ μ -SC 6 H 3 (CH 3 )S}] ( L = Ph 2 POCH 2 CH 3 , 2 ; Ph 2 P(4-C 6 H 4 NMe 2 ), 3 ; Ph 2 P(2-C 6 H 4 Ph), 4 ; Ph 2 PCH = CH 2 , 5 ) in 68–88% yields. The complexes 2 – 5 were characterized by elemental analysis, IR, NMR spectroscopy, as well as by X-ray diffraction analysis. Furthermore, the electrochemistry of these complexes was studied by cyclic voltammetry.