“…For example, X-ray diffraction was reported to show 3,6-bis(4-chlorobenzyl)-1,4-dihydro-1,2,4,5-tetrazine to have an obvious chair conformation without homoaromatic structure, 8 but 1,3,4,6-tetramethyl-1,4dihydro-1,2,4,5-tetrazine was analysed by X-ray diffraction and a possible homoaromatic structure was identified. 9 There seems to be much confusion over the structures of 1,2-and 1,4-dihydro-1,2,4,5-tetrazine isomers, and the same compound is often formulated as both structures. In most cases, the dihydro structure which would be the first reaction product is presented, or the authors have formulated their compounds in the dihydro structure which seemed to be the most accepted at that time.…”