Synthesis and structure of the mercury chloride complex of 2,2′-(2-bromo-5-tert-butyl-1,3-phenylene)bis(1-methyl-1H-benzimidazole)

Abstract

In the title mercury complex, the HgII atom is coordinated by two Cl atoms and by two N atoms from two 2,2′-(2-bromo-5-tert-butyl-1,3-phenyl­ene)bis­(1-methyl-1H-benzimidazole) ligands, which gives rise to a zigzag helical 1-D polymer propagating along the b-axis direction.

Structure of the mercury(II) mixed-halide (Br/Cl) complex of 2,2′-(5-tert-butyl-1,3-phenylene)bis(1-pentyl-1H-benzo[d]imidazole)

“…The dihedral angles between the two sets of benzimidazole moieties are 76.4 (3) and 88.0 (2) ( Table 1), while their dihedral angles with the central ring are 60.1 (3)/59.5 (3) and 50.1 (3)/60.2 (2) . These values are significantly different from those observed in the related complex (Rani et al, 2017), where the corresponding angles are 54.9 (6) and 65.6 (4) between the two benzimidazole moieties (two values due to the disorder of one of these moieties) and 55.6 (1) and 89.3 (5)/79.2 (5) with the central ring. Further, the four pentyl side chains have adopted quite different conformations.…”

“…There are two such sites in the asymmetric unit and in one site, the Br/Cl occupancy is 0.599 (9):0.401 (9) and in the other site the ratio is 0.431 (9):0.569 (9), giving an overall composition (L) 2 HgBr 1.52 Cl 0.48 , where L is 2,2 0 -(5-tert-butyl-1,3-phenylene)bis(1-pentyl-1H-benzimidazole). Unlike the case with the recently published structure (Rani et al, 2017) of a related ligand where both coordinating positions are blocked by substituents (Br and tert-butyl), even though in the present ligand one position is open for the formation of an Hg-C bond, the basic arrangement is the same as in the previous structure.…”

“…The two sets of Hg-N bond lengths are 2.313 (7)/2.343 (6) and 2.316 (6)/2.327 (6) Å , which span a wider range than that observed (Rani et al, 2017) in a structurally similar complex [2.333 (4)-2.338 (4) Å ]. The two sets of Hg-Cl and Hg-Br bond lengths are 2.37 (2)/2.48 (4) (the larger s.u.…”

Structure of 2,2′-(5-tert-butyl-1,3-phenylene)bis(1-pentyl-1H-benzimidazol-3-ium) tetrachloridomercurate(II)

“…2. Unlike a similar structure published recently containing a closely related ligand (Rani et al, 2017a), where the Hg atom is bonded to an N atom from the benzimidazole moiety, in this instance a salt has been obtained due to the different conditions of the reaction. The structure has been published of a salt containing the tetrachloridomercurate(II) anion (Herbst et al, 2013) and a closely related ligand with nhexyl rather than n-pentyl side chains, which was the result of an attempted transmetallate reaction between Hg and Au.…”

Synthesis, biological evaluation and model membrane studies on metal complexes containing aromatic N,O-chelate ligands

“…In addition to their biological relevance, this motif is broadly used as ligand in organometallic and coordination chemistry. For example, 2-arylbenzimidazoles can form bonds through substituents on the benzene ring (non-core) and the nitrogen atom (with sp 2 hybridization) of the imidazole, forming stable complexes with various metals, either as monodentate ligands [6,7], N,O-chelate bidentate ligands [8,9], or N,N,O-chelate tridentate ligands [10]. However, the studies of complexes of 2-arylbenzimidazoles with rare earth elements are scarce [11].…”