Metal Complexes with an Intact, Coordinating but Bent Organoazide Ligand

6 Metal Complexes with an Intact, Coordinating but Bent Organoazide Ligand 

Parallel to the work of Bergman et al., Cummins et al. published a closely related system obtained from a vanadium(in) precursor and mesityl azide leading to a vanadium(V) diazenylimido complex, which loses dinitrogen already at room temperature. Interestingly, the loss of dinitrogen from the vanadium(V)diazenylimido complex follows second-order kinetics and crossover was found in a double labelling experiment, which is in contrast to the observations of Bergman et al. with tantalum complexes. 

Just a few years later, Floriani et al. described the reaction between a tungsten(IV) calixarene system and phenyl azide giving under oxidation to tungsten(VI) the corresponding diazenylimido complex, which again looses dinitrogen.  

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