Nitriles imido metal complexes

In the imido systems the n n transition is shifted to lower energy (518 nm) and markedly decreases in intensity. On the other hand, upon substitution of the anionic trans-ligands by acetonitrile the n->-n transition is found at 450 nm, shifting to 525 nm upon protonation. Moreover, the metal-N(nitrido) stretching frequency increases to 1016 cm From a chemical viewpoint it is important that the nitrido-nitrile complex can be... 

Cyclopentadienylamine)scandium(2,3-dimethyl-l,3-butadiene) 7 was synthesized in good yield, as shown in Scheme 2. Complex 7 reacted with benzonitrile to form a /rz-imido complex 8, the structure of which was characterized by single crystal X-ray diffraction. This product 8 was proposed to be formed by nitrile insertion followed by an attack of another diene methylene group on the carbon atom of the imido intermediate.3 An unsaturated metal imido species was formed, which easily dimerized to produce 8. However, the yield of 8 was not reported. 

This is analogous to the previously described method (Section II,A,2) for making bridging-dinitrogen complexes. Metal chlorides and hydrides also react with nitriles to yield imido complexes, as shown in reaction (77) (6, 165, 280). 

It is possible to synthesize imido complexes by cleavage of a N-H or N-Si bond of an amine, upon complexation with an oxide or a metal chloride, by metathesis, by reaction with a nitrile, by electrophilic attack of a nitride or by other reactions of various nitrogen-containing precursors ... 

The CP3UCHPR3 complexes also undergo insertion into the CsN bonds of nitriles and the C s O bonds of metal carbonyls. Thus, Cramer et al. [39] reported that insertion reactions with acetonitrile yield uranium imido complexes ... 

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