Structure of 2,2'-(5- tert-butyl-1,3-phenyl-ene)bis-(1-pentyl-1 H-benzimidazol-3-ium) tetra-chlorido-mercurate(II)

Varsha Rani; Harkesh B Singh; Ray J Butcher

doi:10.1107/S2056989017004303

Structure of 2,2'-(5- tert-butyl-1,3-phenyl-ene)bis-(1-pentyl-1 H-benzimidazol-3-ium) tetra-chlorido-mercurate(II)

Acta Crystallogr E Crystallogr Commun. 2017 Mar 24;73(Pt 4):560-563. doi: 10.1107/S2056989017004303. eCollection 2017 Apr 1.

Authors

Varsha Rani¹, Harkesh B Singh¹, Ray J Butcher²

Affiliations

¹ Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400 076, India.
² Department of Chemistry, Howard University, 525 College Street NW, Washington, DC 20059, USA.

Abstract

In the title salt, (C₃₄H₄₄N₄)[HgCl₄], the [C₃₄H₄₄N₄]²⁺ cations and [HgCl₄]^2- anions are linked by N-H⋯Cl hydrogen bonds. One of the two n-pentyl side chains was refined as disordered over two sets of sites, with occupancies of 0.733 (18) and 0.267 (18). The geometry around the Hg^II atom in the [HgCl₄]^2- anion is distorted tetra-hedral, with bond angles ranging from 98.16 (3) to 120.68 (3)°. In the [HgCl₄]^2- anion, there are two short Hg-Cl bonds [2.4120 (9) and 2.4171 (11) Å], one inter-mediate Hg-Cl bond [2.4716 (12) Å] and one long Hg-Cl bond [2.6579 (13) Å] for the Cl atom involved in a trifurcated hydrogen bond as an acceptor, including two N-H⋯Cl⋯H-N interactions as well as one C-H⋯Cl inter-action. There are several C-H⋯Cl inter-actions, with C⋯Cl distances ranging from 3.492 (3) to 3.796 (3) Å. These link the cations and anions into a zigzag chain along the c-axis direction. In addition, there are Cl⋯Cl halogen bonds, as well as π-π inter-actions, with centroid-to-centroid distances of 3.4765 (18) Å, which link one of the two benzimidazole moieties into dimeric units.

Keywords: (benzimidazol-2-yl)benzene ligands; crystal structure; hydrogen bonding; tetrachloridomercurate(II) salt.