Some organoperoxo complexes of Zr(IV), Th(IV), Mo(VI), W(VI) and U(VI)

New organoperoxo complexes containing S-benzyldithiocarbazate, NH2NHCSSCH2C6H5(L) have been synthesized and characterized. The complexes have the general formulae, M(L-)2(O2), [M=Zr(IV) and Th(IV)], M'(L-)2(O2)2, [M'=Mo(VI), W(VI) and U(VI)] and M'(L-)2(O2)2.L', [M'=W(VI) and U(VI), L'=OPPh3 or OAsPh3 and L-=deprotonated form of S-benzyldithiocarbazate]. The complexes could only be prepared in alkaline medium where L behaves as a uni-negative bidentate ligand. The IR spectra of the complexes reveal that v1 mode of the M(O2) grouping, which is essentially ν(O-O), shifts to lower wavenumbers with increase in atomic number of metals in a particular group. The IR spectra also indicate that the v1 mode varies somewhat with the choice of L'L; arsine oxides give rise to generally lower frequencies. The complexes oxidize PPh3 and AsPh3 to OPPh3 and OAsPh3, respectively. (author)