Reaction of Aryl Diazonium Salts and Diiron(I) Dithiolato Carbonyls: Evidence for Radical Intermediates

Treatment of Fe2(pdt)­(CO)4(dppv) (1) with aryldiazonium salts affords the 34 e– adducts [Fe2(pdt)­(μ-N2Ar)­(CO)4(dppv)]+ (pdt2– = 1,3-propanedithiolate, dppv = cis-C2H2(PPh2)2). Under some conditions, the same reaction gave substantial amounts of [1]+, the product of electron transfer. Consistent with the influence of electron transfer in the reactions of some electrophiles with Fe­(I)­Fe­(I) dithiolates, the reaction of [Me3S2]+ and Fe2(pdt)­(CO)4(dppbz) was found to give [Fe2(pdt)­(CO)4(dppbz)]+ as well as Me2S and Me2S2 (dppbz = 1,2-bis­(diphenylphosphino)­benzene).