Carbonyl halides of the Group VI transition metals. XX. Substituted dialkyldithiocarbamato complexes of molybdenum halocarbonyls and their oxidation

Abstract

Complexes of the type Mo(CO)₂RPh₃(dtc)₂ (R = P, As, Sb; dtc = dialkyldithiocarbamato) have been prepared by the interaction of sodium dialkyldithiocarbamates with, for example, dichlorobis(triphenylphosphine)trioarbonylmolybdenum(11). In solution the complexes are susceptible to oxidation, but the product obtained depends strongly upon the nature of the solvent used. In acetone solution oxidation yields complexes of the type No₂O₃(dtc)₄; this reaction is very similar to that reported previously for the oxidation of the parent compounds Mo(CO)₃(dtc)₂ and Mo(CO)₂(dtc)₂. However, oxidation of Mo(CO)₂RPh₃(dtc)₂ in carbon tetrachloride-benzene mixture gives molybdenum(VI) derivatives of empirical formulae MoO₂(dtc)₂. The properties of these compounds are different from those reported by Moore and Larson for other compounds of the same formula. Infrared and mass spectrometric studies have shown that our complexes are dimeric and it has been confirmed that those of Moore and Larson are monomeric.