Arderne Charmaine, Olivier Denise K, Ndinteh Derek T
Department of Chemistry, University of Johannesburg, PO Box 524, Auckland Park, Johannesburg 2006, South Africa.
Department of Applied Chemistry, University of Johannesburg, PO Box 524, Auckland Park, Johannesburg 2006, South Africa.
Acta Crystallogr C Struct Chem. 2015 Feb;71(Pt 2):146-51. doi: 10.1107/S2053229615001047. Epub 2015 Jan 24.
The 100 K structures of two salts, namely 2-amino-1H-benzimidazolium 3-phenylpropynoate, C7H8N3(+)·C9H5O2(-), (I), and 2-amino-1H-benzimidazolium oct-2-ynoate, C7H8N3(+)·C8H11O2(-), (II), both have monoclinic symmetry (space group P21/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.
