Diazene ligand

Upon coordination, the diazene ligand can adopt one of three potential configurations (16-18). 

The total electronic coordination energy of frans-diazene is —73.1 kJ/mol including the estimated total hydrogen bond energy of (—)20 kJ/mol for the mononuclear complex irons-2(N2H2) (see above). Thus, the stabilization of the unstable diazene ligand by hydrogen... 

Oxidation of the hydrazine complex formed by the reaction of (t] -C5H5)Mn(CO)2(THF) with hydrazine (Scheme 9.2) gives a dinitrogen complex (t -C5H5)Mn(CO)2(N2). Methylation of the N2 ligand with MeLi followed by treatment with methyl cation converts the N2 complex into a dimethyldiazene complex, from which the diazene ligand is released by applying N2 pressure (eq (3)) [10]. 

Neither 77 nor 79 could be converted to diazene complexes Cp2M=N—NH2 (M = Ti, V) by desilylation with ethereal hydrochloric acid because along with the Me3Si/H exchange, the diazene ligand is dislodged (49). The protolysis [Eq. (125)] takes place in 90% (Ti) and 75%... 

Insertion reactions of arenediazonium ions into metal-carbon bonds are rather rare. Legzdins et al. (1989) found the chromium complex 10.40 with a methyl-(aryl)diazene ligand in the reaction of [Cr(C5H5)(NO)2(CH3)] with 4-nitrobenzene-diazonium tetrafluoroborate. 

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