Date Published: August 01, 2012
Publisher: International Union of Crystallography
Author(s): Ioannis Tiritiris, Willi Kantlehner.
In the title molecular salt, C14H22N3+·Br−, the ring incorporating the guanidinium grouping exhibits a half-chair conformation and the dihedral angle between the N—C—N and C—C—C planes is 55.0 (3)°. The C—N bond lengths in the central CN3 unit are 1.333 (4), 1.338 (3) and 1.341 (4) Å, indicating partial double-bond character. The central C atom is bonded to the three N atoms in a nearly ideal trigonal–planar geometry and the positive charge is delocalized in the CN3 plane. The distances between the N atom and the terminal methyl C atoms [1.453 (4)–1.461 (4) Å] are all close to a typical single C—N bond length.
For the crystal structure of N,N,N′,N′- tetramethylchloroformamidinium chloride, see: Tiritiris & Kantlehner (2008 ▶). For the synthesis of 1-methyl-2-dimethylamino-1,4,5,6-tetrahydropyrimidine and derived guanidinium salts, see: Tiritiris & Kantlehner (2012b ▶). For the structure of 2-dimethylamino-1-(2-ethoxy-2-oxoethyl)-3-methyl-3,4,5,6-tetrahydropyrimidin-1-ium tetraphenylborate see: Tiritiris & Kantlehner (2012a ▶).