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 <b>6</b> is reported, and the alkene-like reactivity of compound <b>6</b> is described. The compound's structure and reactivity suggest that <b>6 </b>is not aromatic. This conclusion is corroborated by computational results on <b>6</b> and related compounds including homodesmotic reactions to test for aromatic stabilization, NICS calculations, and NBO calculations. Compound <b>6</b>, and 1,2-dihydrodiazetes in general, are concluded to be strained heterocycles with no indication for aromatic stabilization.