Synthesis and structure of an arylselenenium(II) cation, [C34H41N4Se+]2[Hg(SeCN)4]2−, based on a 5-tert-butyl-1,3-bis(1-pentyl-1H-benzimidazol-2-yl)benzene scaffold

Abstract

In the title salt, bis{[5-tert-butyl-1,3-bis(1-pentyl-1H-benzimidazol-2-yl)benzene]selenium} tetrakis(selenocyanato)mercury, (C34H41N4Se)2[Hg(SeCN)4], the arylselenenium cations, [C34H41N4Se]+, are linked through [Hg(SeCN)4]2− anions by C—H...N hydrogen bonds. In the cation, the geometry around the Se atom in the 5-tert-butyl-1,3-bis(1-pentyl-1H-benzimidazol-2-yl)benzene scaffold is T-shaped, resulting from the coordination of Se by the C atom of the central aromatic ring and the N atoms of both of the benzimidazole moieties. The trans Se—N bond lengths are almost equal [2.087 (3) and 2.099 (3) Å] and the Se—C bond length is 1.886 (3) Å. The N—Se—N angle is 159.29 (11)°. The geometry around the HgII atom in the [Hg(SeCN)4]2− anion is distorted tetrahedral, with Se—Hg—Se angles ranging from 88.78 (3) to 126.64 (2)°. In [Hg(SeCN)4]2−, the Hg—Se bonds are unsymmetrical [2.5972 (4) and 2.7242 (5) Å]. One of the pentyl substituents is disordered over two equivalent conformations, with occupancies of 0.852 (8) and 0.148 (8).

Keywords

• crystal structure
• arylselenenium(II) cation
• tetraselenocyanatemercury(II) anion