Dinitrogen bonding

The existence of side-on dinitrogen bonded to nickel in the structures (57) and (58) has recently been explained within the EH formalism in terms of n back-bonding interactions.24 ... 

The rate of substitution reactions can give a measure of the activation energy, and with the usual assumptions of transition state theory, the metal-dinitrogen bond energy. The enthalpy value thus obtained (88) for [Mo(N2)2(Ph2PCH2CH2PPh2)2] is 116 kJ mol-1. Parallel stud-... 

Dinitrogen has been shown to adopt an end-on bonding arrangement in those phosphine-containing complexes that have been isolated and characterized. In most of these complexes, dinitrogen bonds in a linear end-on arrangement either to one metal G (e.g., 15, 23, 43, 50, 52, and... 

Organophosphine ligands are particularly successful in helping the metal provide a favorable coordination site that is sufficiently electron-rich to provide strong back-donation into the vacant dinitrogen tt -orbitals and help stabilize the metal-dinitrogen bond. 

For a given electron complement the nature of the metal, the co -ligands and the geometry of the complex also influence the stability of the metal - dinitrogen bond [11-14]. 

Dinitrogen Bond Scission and Ammonia Formation with the B-Diketimate Ligand System... 

Smith JM, Lachicotte RJ, Pittard KA, et al. Stepwise reduction of dinitrogen bond order by a low-coordinate iron complex. J Am Chem Soc. 2001 123 9222-9223. Smith JM, Sadique AR, Cundari TR, et al. Studies of low-coordinate iron dinitrogen complexes. J Am Chem Soc. 2006 128 756-769. 

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