title: 9-Ethynyl-9H-carbazole.
abstract: The title compound, C(14)H(9)N, is the second crystallographically characterized example of an ynamine with an H atom in the C-terminal position. There are two independent mol-ecules (A and B) in the asymmetric unit. The structures of both mol-ecules are essentially planar (r.m.s. deviation = 0.0312 and 0.0152 Å). The N-C(sp) bond lengths are 1.353 (4) and 1.350 (4) Å, and those of the acetyl-ene bonds are 1.189 (4) and 1.190 (4) Å. The C(sp)-H bond lengths are 0.95 (5) and 0.97 (4) Å. These geometries are consistent with those of the previously reported ynamine characterized by crystallography. In the crystal, the mol-ecules stack along the c axis, forming two kinds of columnar structures. The acetyl-ene C atoms of mol-ecule A have a short contact [3.341 (4) Å and 3.396 (4) Å] with an adjacent mol-ecule A at the C-C bond of the fused part, which originates in π-π stacking inter-action; no remarkable spatial contact is recognized within the stacking of mol-ecule B.
authors.affiliation: Department of Material Science and Chemistry, Wakayama University, Sakaedani, Wakayama, 640-8510,  Japan.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Tabata
authors.forename: Tsunehisa
authors.initials: T
authors.lastname: Okuno