Crystal structure, Hirshfeld surface analysis and DFT study of 6-bromo-3-(5-bromo-hex-yl)-2-[4-(di-methyl-amino)-phen-yl]-3 H-imidazo[4,5- b]pyridine

Acta Crystallogr E Crystallogr Commun. 2020 Jul 10;76(Pt 8):1234-1238. doi: 10.1107/S2056989020008889. eCollection 2020 Aug 1.


In the title mol-ecule, C20H24Br2N4, the imidazo-pyridine moiety is not planar as indicated by the dihedral angle of 2.0 (2)° between the constituent rings; the 4-di-methyl-amino-phenyl ring is inclined to the mean plane of the imidazole ring by 27.4 (1)°. In the crystal, two sets of C-H⋯π(ring) inter-actions form stacks of mol-ecules extending parallel to the a-axis direction. Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from H⋯H (42.2%), H⋯C/C⋯H (23.1%) and H⋯Br/Br⋯H (22.3%) inter-actions. The optimized structure calculated using density functional theory (DFT) at the B3LYP/ 6-311 G(d,p) level is compared with the experimentally determined structure in the solid state. The calculated HOMO-LUMO energy gap is 2.3591 eV.

Keywords: C—H⋯π(ring) inter­action; DFT calculation; Hirshfeld surface analysis; crystal structure; imidazo­pyridine.

Grant support

This work was funded by Tulane University grant . Hacettepe University Scientific Research Project Unit grant 013 D04 602 004 to T. Hökelek.