Crystal structure and Hirshfeld surface analysis of 4-allyl-6-bromo-2-(4-chloro-phen-yl)-4H-imidazo[4,5-b]pyridine

The title compound, C15H11BrClN3, is built up from a planar imidazo[4,5-b]pyridine unit linked to phenyl and allyl substituents. The allyl substituent is rotated significantly out of the imidazo[4,5-b]pyridine plane, while the benzene ring is inclined by 3.84 (6)° to the ring system. In the crystal, mol-ecules are linked via a pair of weak inter-molecular C-H⋯N hydrogen bonds, forming an inversion dimer with an R 2 2(20) ring motif. The dimers are further connected by π-π stacking inter-actions between the imidazo[4,5-b]pyridine ring systems [centroid-centroid distances = 3.7161 (13) and 3.8478 (13) Å]. The important contributions to the Hirshfeld surface are H⋯H (35.9%), H⋯Cl/Cl⋯H (15.0%), H⋯C/C⋯H (12.4%), H⋯Br/Br⋯H (10.8%), H⋯N/N⋯H (7.5%), C⋯Br/Br⋯C (5.9%), C⋯C (5.5%) and C⋯N/N⋯C (4.0%) contacts.