The title compound, C16H13N5, was synthesized by coupling aminotetrazole with chalcone in the presence of an amine organocatalyst derived from chincona alkaloid. There are two molecules, A and B, in the asymmetric unit. In molecule A, the dihedral angles between the partly hydrogenated pyrimidine ring system (r.m.s. deviation = 0.056 Å) and the sp2- and sp3-bonded phenyl groups are 33.32 (11) and 86.53 (11)°, respectively. The equivalent data for molecule B are 0.049 Å, and 27.05 (10) and 85.27 (11)°, respectively. In the crystal, A+B dimers linked by pairs of N—H...N hydrogen bonds generate R22(8) loops. The dimers are linked by aromatic π–π stacking interactions [shortest centroid–centroid separation = 3.5367 (15) Å], which results in a three-dimensional network.