1,4-Di-[2-phenyl-1-diazenyl]perhydro-1,4-diazepine: X-ray crystal structure

1,4-Di-2-phenyl-1-diazenyl]perhydro-1,4-diazepine (1) has been synthesized by reaction of benzenediazonium chloride with homopiperazine (perhydro-1,4-diazepine). The crystal structure of 1 has been determined by single crystal X-ray diffraction analysis. The bis-triazene (1) adopts an extended conformation which precludes any close intramolecular interaction of the phenyl rings. The heterocyclic seven-membered ring adopts a chair conformation, with the triazene side chains occupying alternate axial and equatorial positions consistent with cis-geometry. Internal torsion angles of the seven-membered ring have been measured. The crystal packing is determined by short contacts between C=H groups of phenyl rings and nitrogens of triazene moieties and by van der Waals interactions, with no evidence for intermolecular – interactions. This work establishes the structure of the product of diazonium coupling with homopiperazine as 1,4-di(E)-2-phenyl-1-diazenyl]perhydro-1,4-diazepine. Crystal data: 1 C₁₇H₂₀N₆, monoclinic, space group P2₁/n, a = 9.1838(5) Å, b = 12.1095(6) Å, c = 15.0081(8) Å, = 101.320(2), V = 1636.6(2) Å,³ for Z = 4.