Atomic nitrogen partially hydrogenated

For reasons already frequently mentioned—cf., for example, pp. 106,178,196—the partially hydrogenated aromatic nucleus is not stable hence the bracketed intermediate product tends to change into the benzenoid form, while hydrogen wanders from the nitrogen to the oxygen atom. 

Triazene dyes in which the terminal nitrogen atom is cyclically bound are obtained by coupling heterocyclic diazonium salts with partially hydrogenated N heterocycles. In 17 alkylation was subsequently performed with ethylene oxide [40],... 

This requires that the carbonyl carbon, the nitrogen, and the two atoms attached to each of them (the a-carbon and the oxygen bonded to the carbonyl carbon and the hydrogen and the other a-carbon bonded to the nitrogen) must all lie in the same plane. The most stable conformation has the bulky a-carbons in a trans relationship about the carbon-nitrogen partial double bond, as shown in the preceding structure. 

Fastrup et al. [9] presented a detailed experimental study of the hydrogenation of an iron-based surface precovered with atomic nitrogen using the temperature-programmed surface reaction (TPSR) method. Their modeling results clearly demonstrate the effect of the initial coverage of N- and the effect of the H2 partial pressure. The kinetic mechanism of the TPSR experiment can be written as depicted below. 

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