Wayne L. Carrick

The nature of the decomposition of phenylvanadium oxide dichloride

The reaction of diphenylmercury and vanadium oxide trichloride in cyclohexane solution at 25° initially yielded phenylmercuric chloride and the unstable phenylvanadium oxide dichloride whose decomposition has been studied. When a diphenylmercury/vanadium oxide trichloride ratio > 1 was employed, the biphenyl formation rate was accelerated and more than one chlorine on the vanadium was replaced by a phenyl group. When this ratio was < 1, the rate of biphenyl appearance was retarded and, on acid hydrolysis, benzene, phenol and biphenyl were recovered. It was shown that all cyclohexane-soluble, phenyl-bearing species (e.g. PhnVOCl3-n, Ph2Hg) interchanged phenyl groups very rapidly. The appearance of biphenyl was thought to be due to the concerted decomposition of an unstable di-σ-phenylvanadium intermediate.