Synthesis and X-ray crystallographic analysis of some 1,6-dihydro-1,2,4,5- tetrazines

Abstract

Eight 1,6-dihydro-1,2,4,5-tetrazines (2a-2h) were synthesised by reaction of sodium borohydride with 3,6-substituted-1,2,4,5-tetrazines. The structure of 2c was confirmed by single-crystal X-ray diffraction. The central six-membered ring of 2c has an obvious unsymmetrical boat conformation. It could be considered that the molecule has a homoaromaticity.