Crystal structure and Hirshfeld surface analysis of 6-amino-8-phenyl-1,3,4,8-tetra-hydro-2 H-pyrido[1,2- a]pyrimidine-7,9-dicarbo-nitrile

Abstract

In the title compound, C₁₆H₁₅N₅, the 1,4-di-hydro-pyridine ring has a shallow boat conformation, while the 1,3-diazinane ring adopts an envelope conformation. In the crystal, pairwise N-H⋯N hydrogen bonds generate centrosymmetric dimers featuring R ² ₂(12) motifs and C-H⋯N contacts connect these dimers to form double layers lying parallel to (001). Weak C-H⋯π and N-H⋯π inter-actions help to consolidate the double layers and van der Waals inter-actions occur between layers. A Hirshfeld surface analysis indicates that the most significant contributions to the crystal packing are from H⋯H (38.5%), N⋯H/H⋯N (33.3%) and C⋯H/H⋯C (27.3%) contacts.

Keywords: Hirshfeld surface analysis; crystal structure; cyclo­addition product; pyrido[1,2-a]pyrimidine.