Crystal structure of 4-amino-1-(4-methylbenzyl)pyridinium bromide

Abstract

The title mol­ecular salt, C13H15N2 +·Br−, crystallized with two independent ion pairs (A and B) in the asymmetric unit. In the cations, the planes of the pyridine and benzene rings are inclined to one another by 79.32 (8) and 82.30 (10)° in ion pairs A and B, respectively. In the crystal, the anions and cations are connected by N—H⋯Br hydrogen bonds, forming a centrosymmetric tetra­mer-like unit enclosing an R 8 4(16) ring motif. These units are linked via C—H⋯Br hydrogen bonds, forming a three-dimensional network.

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

“…However, the N2-C15 bond length [1.325 (2) Å ] is shorter than expected for an NH 2 -C ar single bond [1.38 (3) Å ], indicating partial double-bond character. Similar bond lengths are found in related compounds with an N + C double bond (Chidan Kumar et al, 2017;Sharmila et al, 2014;Yue et al, 2013).…”

The crystal structure of zwitterionic 2-{[(4-iminiumyl-3-methyl-1,4-dihydropyridin-1-yl)methyl]carbamoyl}benzoate hemihydrate

“…1) are generally within normal ranges. However, the N3-C3 [1.335 (3) Å in both molecules] are shorter than expected for an NH 2 -C ar single bond [1.38 (3) Å ], but are similar to those found in related compounds with an N + C double bond (Sharmila et al, 2014;Sun et al, 2015). The C-O bonds in the carboxylate units [C15A-O3A = 1.247 (3) Å and C15A-O2A = 1.257 (3) Å ] in molecule A, with comparable values in molecule B, are similar to values found in other deprotonated carboxylate groups (Hemamalini & Fun, 2010).…”

“…A search for iminopyridine derivatives using 4-( 4 -azanylidene)-4H-1 2 -pyridine as the skeleton gave 15 hits, although none of these were zwitterionic derivatives comparable to the title compound. Of these, only three had aromatic rings in the cation in addition to the iminopoyridine unit (Sharmila et al, 2014;Pei et al, 2013)…”

Crystal structure and Hirshfeld surface analysis of a pyridiniminium bromide salt: 1-[2-([1,1′-biphenyl]-4-yl)-2-oxoethyl]-3-methyl-1,4-dihydropyridin-4-iminium bromide

“…The bond lengths and angles in the cation are generally within normal ranges. However, the N2-C17 bond [1.337 (2) Å ] is shorter than expected for an NH 2 -C ar single bond [1.38 (3) Å ] although similar bond lengths have been observed in related compounds with an N + C double bond (Chidan Kumar et al, 2017;Sharmila et al, 2014;Yue et al, 2013).…”