ACTA CRYSTALLOGRAPHICA SECTION E-CRYSTALLOGRAPHIC COMMUNICATIONS, vol.80, pp.378-382, 2024 (ESCI)
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 angstrom), while the 1,3-diazinane ring has a distorted twist-boat conformation. In the crystal, molecules are linked by N-H center dot center dot center dot N and C-H center dot center dot center dot N hydrogen bonds, forming a three-dimensional network. In addition, C-H center dot center dot center dot pi interactions form layers parallel to the (100) plane. Thus, crystal-structure cohesion is ensured. According to a Hirshfeld surface study, H center dot center dot center dot H (40.4%), N center dot center dot center dot H/H center dot center dot center dot N (28.6%) and C center dot center dot center dot H/H center dot center dot center dot C (24.1%) interactions are the most important contributors to the crystal packing.