Date Published: April 01, 2011
Publisher: International Union of Crystallography
Author(s): Jasmin Preis, Dieter Schollmeyer, Heiner Detert.
The title compound, C19H16N4, is one of the few known 3,7-diaryl-1,2,4-triazolo[4,3-c]pyrimidines. The triazolopyrimidine unit is essentially planar (r.m.s. deviation = 0.048 Å). The phenyl ring and the heterocyclic core subtend a dihedral angle of only 15.09 (6)°, whereas the m-tolyl ring is twisted by 71.80 (6)° out of the plane of the triazole ring. Two C—H⋯N hydrogen bonds and π–π stacking interactions [centroid–centroid distance = 3.7045 (8) Å] stabilize the crystal packing.
For the synthesis of higher conjugated and annulated heterocyclic π-systems, see: Detert & Schollmeyer (1999 ▶); Sugiono & Detert (2001 ▶). The acylation of tetrazoles with chloroazines and thermal ring transformation leads to triazolo annulated azines, see: Huisgen, Sauer & Seidel (1960 ▶); Huisgen, Sturm & Markgraf (1960 ▶); Huisgen et al. (1961 ▶); Glang et al. (2008 ▶). Whereas a broad variety of triazolopyrimidines are known, only two further [1,2,4]triazolo[4,3-c]pyrimidines with a 3,7-diaryl substitution have been reported so far, see: Seada et al. (1992 ▶).