Amine-Nitrile Hydrogen Bonding: Tetracyanoethylene as Electron Donor in the Carbazole-Tetracyanoethylene 1:2 Complex
Journal of Organic Chemistry
The crystal and molecular structure of the carbazole-tetracyanothylene (TCNE) molecular complex is examined by single-crystal X-ray diffraction. The complex crystallizes in the monoclinic space group P2,/n, a = 7.273 A, b = 6.129 A, c = 22.942 A, p = 95.76', V = 1017.5 A3, Z = 4, final residual values R = 0.067, R, = 0.058. The complex in the solid state has the unusual stoichiometry 1 carbazole:2 TCNE. The carbazole is centrosymmetrically disordered about the origin of the unit cell and participates in intermolecular hydrogen bonding between the amino hydrogen (H9) of carbazole and a nitrile lone electron pair of TCNE with angles (carbazole) N9-H9-.NT5 (TCNE) 168' and (carbazole) H9-NT5=CT5 (TCNE) 156', distance (carbazole) N9-NT5 (TCNE) 3.155 A. Additionally, apparent T interactions involving carbazole and TCNE are less extensive than in related complexes.
Masnovi, J.; Baker, R. J.; Towns, R. L. R.; Chen, Z. Amine-nitrile hydrogen bonding: tetracyanoethylene as electron donor in the carbazole-tetracyanoethylene 1:2 complex. J. Org. Chem. 1991, 56, 176-179.