Hydrazido complexes bridging

There is only one reported mononuclear hydrazido(2—) complex for the titanium group, [Ti(r/5-CjHj)2(NNSiMe3)2].498 Other hydrazido complexes are known but involve bridging hydrazido groups (see below). For reasons not yet fully understood, titanium is apparently reluctant to form four electron metal-nitrogen multiple bonds. 

Complexes of the (ra s-lTcO(OH)] and [TCO2] Cores Oxo-Bridged (Tc203l and Other Binuclear Complexes [TcSl Complexes Nitrido Complexes Imido and Hydrazido Complexes Complexes Not Containing Multiply Bonded Ligands... 

A proposed reaction pathway by which ammonia is formed is shown in Scheme 6. After the dissociation of phosphine, attack by another hydrazido complex (e.g., A) to form a bridged species, C, is proposed. Hydrazido complexes such as A are known to be good nucleophiles. For example, they react in acid catalyzed reactions with aldehydes and ketones to form diazoalkane complexes (e.g.. Equations 4 and... 

Recrystallization of 40d in the presence of A TV-dimethylbydrazine affords the N,N-dimethylhydrazine-bridged dinuclear vanadinm(V) hydrazido complex 40d-DMH-40d. The single-crystal X-ray structure determination of 40d-DMH-40d confirms that two 40d units are bridged by 7V,A -dimethylhydrazine to form the 2 1 complex in anti-configuration, wherein each vanadium center is a hexacoordi-nate geometry (Fig. 3.30b) [114]. This hydrazido complex 40d-DMH-40d has the near-linear V(l)-N(2)-N(3) angles of 171.8(7) and 174.0(7)° with the V(l)-N(2) distances of 1.663(7) and 1.690(7) A, respectively. 

Figure 88. Generation of diazenido-hydrazido complexes from [Mo02(S2CNR2)2] and their subsequent rearrangement to give binuclear diazenido-bridged complexes.

Hydrazido(2-) complexes, 2,141-151 bond lengths and angles, 2,145 bridging, 2,150 chemistry, 2,145 electrochemical reduction, 2,147 Group VI, 2,148... 

As a bridging ligand the hydrazido(2-) species can be visualized as adopting two forms. Form 25 has been observed only in the complex [ (TJ5-C5H5)Mo(NO)I 2(NNMe2)] (211). 

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