Crystal structure and Hirshfeld surface analysis of two imidazo[1,2-a]pyridine derivatives: N-tert-butyl-2-(4-methoxyphenyl)-5-methylimidazo[1,2-a]pyridin-3-amine and N-tert-butyl-2-[4-(dimethylamino)phenyl]imidazo[1,2-a]pyridin-3-amine

Abstract

In the title imidazo[1,2-a]pyridine derivatives, N-tert-butyl-2-(4-methoxyphenyl)-5-methylimidazo[1,2-a]pyridin-3-amine, C19H23N3O, (I), and N-tert-butyl-2-[4-(dimethylamino)phenyl]imidazo[1,2-a]pyridin-3-amine, C19H24N4, (II), the 4-methoxyphenyl ring in (I) and the 4-(dimethylamino)phenyl ring in (II) are inclined to the respective imidazole rings by 26.69 (9) and 31.35 (10)°. In the crystal of (I), molecules are linked by N - H⋯N hydrogen bonds, forming chains propagating along the [001] direction. The chains are linked by C - H⋯π interactions, forming layers parallel to the (010) plane. In (II), the crystal packing also features N - H⋯N hydrogen bonds, which together with C - H⋯N hydrogen bonds link molecules to form chains propagating along the c-axis direction. The chains are linked by C - H⋯π interactions to form layers parallel to the (100) plane. Inversion-related layers are linked by offset π-π interactions [intercentroid distance = 3.577 (1) Å]. The intermolecular interactions of both compounds were analyzed using Hirshfeld surface analysis and two-dimensional fingerprint plots.