Are 1,2-Dihydrodiazetes Aromatic? An Experimental and Computational Investigation

A thorough experimental and computational investigation of the aromaticity of the 1,2-dihydrodiazete ring system was carried out. The X-ray crystal structure of 1,2-dihydrodiazete 6 is reported,
and the alkene-like reactivity of compound 6 is described. The compound's structure and reactivity
suggest that 6 is not aromatic. This conclusion is corroborated by computational results on 6 and
related compounds including homodesmotic reactions to test for aromatic stabilization, NICS
calculations, and NBO calculations. Compound 6, and 1,2-dihydrodiazetes in general, are concluded
to be strained heterocycles with no indication for aromatic stabilization.