Synthesis and crystal structure of a new mercury(II) chlorine complex with nitronyl nitroxides, C15H19Cl4Hg2N4O2

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

In the title mercury complex, catena-poly[[di-chlorido-mercury(II)]-μ-2,2'-(2-bromo-5-tert-butyl-1,3-phenyl-ene)bis-(1-methyl-1H-benzimidazole)-κ2N3:N3'], [HgCl2(C26H25BrN4)] n , 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-phenyl-ene)bis-(1-methyl-1H-benzimidazole) ligands. The metal cation adopts a distorted tetrahedral coordination geometry with with bond angles around mercury of 100.59 (15)° [N-Hg-N] and 126.35 (7)° [Cl-Hg-Cl]. This arrangement 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-phenyl-ene)bis-(1-pentyl-1H-benzo[d]imidazole)

The mercury(II) complex of 2,2'-(5-tert-butyl-1,3-phenyl-ene)bis-(1-pentyl-1H-benz-imidazole), namely catena-poly[[dihalogenido-mercury(II)]-μ-2,2'-(5-tert-butyl-1,3-phenyl-ene)bis-(1-pentyl-1H-benzimidazole)-κ2N3:N3'], [HgBr1.52Cl0.48(C34H42N4)], 2, has a polymeric structure bridging via the N atoms from the benzimidazole moieties of the ligand. The compound crystallizes in the ortho-rhom-bic space group Pca21 and is a racemic twin [BASF = 0.402 (9)]. The geometry around the HgII atom is distorted tetra-hedral, with the HgII atom coordinated to two N atoms, one Br atom, and a fourth coordination site is occupied by a mixed halide (Br/Cl). For the two ligands in the asymmetric unit, there is disorder with one of the two tert-butyl groups and benzimidazole moieties showing twofold disorder, with occupancy factors of 0.57 (2):0.43 (2) for the tert-butyl group and 0.73 (3):0.27 (3) for the benzimidazole group. In addition, there is threefold disorder for two of the four n-pentyl groups, with occupancy factors of 0.669 (4):0.177 (4):0.154 (4) and 0.662 (4):0.224 (4):0.154 (4), respectively. The mol-ecules form a one-dimensional helical polymer propagating in the b-axis direction. The helices are held together by intra-strand C-H⋯Br and C-H⋯Cl inter-actions. Each strand is further linked by inter-strand C-H⋯Br and C-H⋯Cl inter-actions. In addition, there are weak C-H⋯N inter-strand inter-actions which further stabilize the structural arrangement.