The reaction of molibdenum(VI) dioxo derivatives with hetrocumulenes

The reactions of ArNSO (Ar = p-MeC6H4) with cis-Mo(O)2(chel)2 (chel = S2CNEt2, CH3COCH- COCHH3) give the molybdenum(VI) oxo-arylimido derivatives, Mo(O)(NAr)(hel)2, and sulphur dioxide. From cis-Mo(O)2(S2CNEt2)2 and CyNCO (Cy = C6H11) the dimeric Mo2O3(S2CNEt2)4 is obtained, with the concomitant formation of carbon dioxide and biuret, (CyNHCO)2NCy. The spectroscopic properties of the molybdenum(VI) oxo-arylimido derivatives are reported and the possible reaction mechanisms are discussed