Abstract
The reactions between Mn(CO)5X(X = Cl, Br) and bis(diphenylarsino) methane, dam, have been studied. The most surprising feature of the system is the lack of complexes of the type [Mn(CO)3(dam)X]. Binuclear complexes [Mn2(CO)6(dam)X2] dominate the system and these show unusual disproportionation to Mn0 and Mn11. The reactions with the corresponding ditertiary phosphine, dpm, are much simpler and no binuclear complexes were observed. Infrared and N.M.R. studies have helped to elucidate the structures of the compounds prepared.