Crystal structure and Hirshfeld surface analysis of 6-imino-8-(4-methylphenyl)-1,3,4,6-tetrahydro-2H-pyrido[1,2-a]pyrimidine-7,9-dicarbonitrile

In the ten-membered 1,3,4,6-tetrahydro-2H-pyrido[1,2-a]pyrimidine ring system of the title compound, C17H15N5, the 1,2-dihydropyridine ring is essentially planar (r.m.s. deviation = 0.001 Å), while the 1,3-diazinane ring has a distorted twist-boat conformation. In the crystal, molecules are linked by N—H...N and C—H...N hydrogen bonds, forming a three-dimensional network. In addition, C—H...π interactions form layers parallel to the (100) plane. Thus, crystal-structure cohesion is ensured. According to a Hirshfeld surface study, H...H (40.4%), N...H/H...N (28.6%) and C...H/H...C (24.1%) interactions are the most important contributors to the crystal packing.