Our First Dinitrogen Complexes

Complex 3 was a real surprise. It contained a side-on bound dinitrogen fragment bridging the two zirconium centres with a N-N bond distance of 1.548(7) A, the longest N-N bond distance in a dinitrogen complex. When we 

Dinitrogen Activation by Early Transition Metal-Amido Phosphine Complexes 

Despite the faet that we had in our hands a strongly activated dinitrogen fragment and a relatively unexploited bonding mode for N2, reaetivity studies were hampered by the fact that the PNP ligand system was prone to phosphorus decoordination. Attempts to add HCl in a controlled fashion generally resulted 

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