Titanium complexes hydrazido

The hydrazido unit can be used as a Cp side arm donor substituent instead of the amido functionality and to stabilize cationic catalytic species. The synthesis and characterization of amido, chloro, and methyl Cp-hydrazido titanium complexes (C5Me4SiMe2NNMe2)TiR2 (R = NMe2, Cl, Me) (Scheme 313) have been made by general... 

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. 

An extensive series of i/2-hydrazido(l —) complexes of titanium have recently been reported467 together with X-ray crystal structures (Table 17). The bonding of the >/2-hydrazido fragment is perceptibly less symmetrical than for the Mo and W complexes due to increased multiple bonding between Ti and the monosubstituted nitrogen. 

The bis(titanium)hydrazido complex formed by HCl reaction with (h -Cp)2TiN2MgCl in MeOH reacts further with HCl to produce ... 

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