Hydrazido 2— > complexes preparation

We have made several other V" complexes by displacing the hydrazine ligand in [V(N2H4)(NS3)] with Cl , N3 CN , MeCN or CNBu , and have prepared a series of imido-complexes [V(NAr)(NS3)] (Ar = various substituted phenyl groups), and of hydrazido-complexes [V(NNR R )(NS3)] (R R = methyl or phenyl) from reactions of [V(0)(NS3)] with aryl isocyanates or 1,1-disubstituted hydrazines, respectively. Structural studies on several of these compounds always reveal trigonal bipyramidal coordination about the V atom. The V-N distance in the V(NS3) system, as a result of the shape of the NS3, is sensitive to... 

The most widely used methods for the syntheses of monohydrazido(2—) complexes have been from the parent hydrazide and metal oxo or halide complexes with formal elimination of water (equation 168), hydrogen halide (equation 169) or trimethylchlbrosilane (equation 170). The preparation of the hydrazido(2—) complexes, shown in equation (169) and (170), shows that the driving force for the formation of metal-nitrogen multiple bonds is such that the N hydrogens are lost. 

Treatment of dinitrogen complexes which cannot be separated. However diazenido complexes can be prepared cleanly by deprotonation of the corresponding hydrazido(2-) complexes with triethylamine or aqueous potassium carbonate (102), in a medium in which the products are insoluble. For example,... 

Like their imido analogues, mixed hydrazido(2-) oxomolybdenum complexes have been prepared, including dx,trani-[Mo(NNRPh)](0)X2(bipy) (X = halide) and [Mo(NNRPh)(0)(acac)2 ]. 

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