Premium
Charge‐assisted hydrogen bonding in salts of 2‐amino‐1 H ‐benzimidazole with 3‐phenylpropynoic acid and oct‐2‐ynoic acid
Author(s) -
Arderne Charmaine,
Olivier Denise K.,
Ndinteh Derek T.
Publication year - 2015
Publication title -
acta crystallographica section c
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.304
H-Index - 17
ISSN - 2053-2296
DOI - 10.1107/s2053229615001047
Subject(s) - hydrogen bond , monoclinic crystal system , molecule , crystallography , benzimidazole , crystal structure , chemistry , ring (chemistry) , hydrogen , ion , stereochemistry , organic chemistry
The 100 K structures of two salts, namely 2‐amino‐1 H ‐benzimidazolium 3‐phenylpropynoate, C 7 H 8 N 3 + ·C 9 H 5 O 2 − , (I), and 2‐amino‐1 H ‐benzimidazolium oct‐2‐ynoate, C 7 H 8 N 3 + ·C 8 H 11 O 2 − , (II), both have monoclinic symmetry (space group P 2 1 / c ) and display N—H...O hydrogen bonding. Both structures show packing with corrugated sheets of hydrogen‐bonded molecules lying parallel to the [001] direction. Two hydrogen‐bonded ring motifs can be identified and described with graph sets R 2 2 (8) and R 4 4 (16), respectively, in both (I) and (II). Computational chemistry calculations performed on both compounds show that the hydrogen‐bonded ion pairs are more energetically favourable in the crystal structure than their hydrogen–bonded neutral molecule counterparts.