Crystal structure and Hirshfeld surface analysis of a pyridiniminium bromide salt: 1-[2-(adamantan-1-yl)-2-oxoethyl]pyridin-4-iminium bromide

In the cation of the title salt, C17H23N2O+center dot Br-, the adamantyl moiety and the pyridiniminium ring are inclined to the ketone bridge by torsion angles of -78.1 (2) (C-C-C=O) and 58.3 (2)degrees (C-C-N-C), respectively, and the ketone bridge has a C-C-C-N torsion angle of 174.80 (15)degrees. In the crystal, the cations are connected into chains parallel to the c axis by C-H center dot center dot center dot O hydrogen bonds. The chains are further linked into layers parallel to the bc plane by N-H center dot center dot center dot Br and C-H center dot center dot center dot Br hydrogen bonds, C-H center dot center dot center dot pi interactions and pi-pi stacking interactions [centroid-to-centroid distance = 3.5657 (11) angstrom]. A Hirshfeld surface analysis, which comprises the d(norm) surface, electrostatic potential map and two-dimensional fingerprint plots, was carried out to verify the contribution of the various intermolecular interactions.