Crystal structure of tetra-methyl-ammonium 1,1,7,7-tetra-cyano-hepta-2,4,6-trienide.

ABSTRACT: The title compound, C₄H₁₂N⁺·C₁₁H₅N₄ ^-, contains one tetra-methyl-ammonium cation and one 1,1,7,7-tetra-cyano-hepta-2,4,6-trienide anion in the asymmetric unit. The anion is in an all-trans conjugated C=C bonds conformation. Two terminal C(CN)₂ di-nitrile moieties are slightly twisted from the polymethine main chain to which they are attached [C(CN)₂/C₅ dihedral angles = 6.1?(2) and 7.1?(1)°]. The C-C bond distances along the hepta-dienyl chain vary in the narrow range 1.382?(2)-1.394?(2)?Å, thus indicating the significant degree of conjugation. In the crystal, the anions are linked into zigzag chains along the [10] direction by C-H?N(nitrile) short contacts. The anti-parallel chains stack along the [110] direction with alternating separations between the neighboring anions in stacks of 3.291 and 3.504?Å. The C-H?N short contacts and stacking inter-actions combine to link the anions into layers parallel to the (01) plane and separated by columns of tetra-methyl-ammonium cations.

SUBMITTER: Bogdanov G 

PROVIDER: S-EPMC6727047 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature