1-Vinyl-5-amino-1H-tetrazole: X-ray molecular and crystal structures and quantum-chemical DFT calculations

The crystal and molecular structures of 1-vinyl-5-amino-1H-tetrazole (VAT) were determined by single crystal X-ray diffraction. The amino group lies in the plane of the tetrazole ring and valence angles around the N atom are close to 120°, the exocyclic CNamino bond being substantially shorter in comparison with “normal” CN bond. Natural bond orbital analysis was performed, using density functional theory B3LYP method, to explain the structural peculiarities of crystalline VAT. By using MO calculations, relative stability of all possible tautomeric forms of protonated VAT molecule was investigated.