research communications
II coordination polymer with an unsymmetrical dipyridyl ligand: catena-poly[[[dichloridomercury(II)]-μ-N-(pyridin-4-ylmethyl)pyridin-3-amine-κ2N:N′] chloroform hemisolvate]
of an HgaDepartment of Food and Nutrition, Kyungnam College of Information and Technology, Busan 47011, Republic of Korea, bDepartment of Science Education, Kyungnam University, Changwon 51767, Republic of Korea, and cResearch Institute of Natural Science, Gyeongsang National University, Jinju 52828, Republic of Korea
*Correspondence e-mail: dh2232@kyungnam.ac.kr, kmpark@gnu.ac.kr
The LCl2]·0.5CHCl3}n (L = N-(pyridin-4-ylmethyl)pyridin-3-amine, C11H11N3), contains one HgII ion, one bridging L ligand, two chloride ligands and a chloroform solvent molecule with half-occupancy that is disordered about a crystallographic twofold rotation axis. Each HgII ion is coordinated by two pyridine N atoms from two symmetry-related L ligands and two chloride anions in a highly distorted tetrahedral geometry with bond angles falling in the range 99.05 (17)–142.96 (7)°. Each L ligand bridges two HgII ions, forming polymeric zigzag chains propagating in [010]. In the crystal, the chains are linked by intermolecular N/C—H⋯Cl hydrogen bonds together with weak C—H⋯π interactions, resulting in the formation of a three-dimensional supramolecular network, which is further stabilized by C—Cl⋯π interactions between the solvent chloroform molecules and the pyridine rings of L [chloride-to-centroid distances = 3.442 (11) and 3.626 (13) Å]. In addition, weak Cl⋯Cl contacts [3.320 (5) Å] between the chloroform solvent molecules and the coordinating chloride anions are also observed.
of the title compound, {[HgKeywords: crystal structure; HgII compound; unsymmetrical dipyridyl ligand; zigzag coordination polymer.
CCDC reference: 1507232
1. Chemical context
A variety of coordination polymers have been explored extensively over the last two decades because of their fascinating architectures and their useful applications in materials chemistry (Silva et al., 2015; Furukawa et al., 2014; Robson, 2008; Leong & Vittal, 2011). In this area of research, symmetrical dipyridyl ligands composed of two terminal pyridines with same substituted nitrogen positions have been used mainly for the design and construction of the coordination polymers. By contrast, investigations based on unsymmetrical dipyridyl ligands, with the nitrogen atoms in different positions on each of the two terminal pyridines, are still rare (Uemura et al., 2008; Khlobystov et al., 2003). Recently, our group and that of Gao have already reported AgI coordination polymers with some unsymmetrical dipyridyl ligands such as N-(pyridine-3-ylmethyl)pyridine-2-amine (Lee et al., 2013; Zhang et al., 2013), N-(pyridine-2-ylmethyl)pyridine-3-amine (Ju et al., 2014; Moon & Park, 2014; Moon et al., 2014; Zhang et al., 2013) and N-(pyridine-4-ylmethyl)pyridine-3-amine (Lee et al., 2015; Moon et al., 2015; Zhang et al., 2013). As a part of our ongoing efforts to construct coordination polymers with such unsymmetrical dipyridyl ligands, we prepared the title compound obtained by the reaction of mercury(II) chloride with an unsymmetrical dipyridyl ligand, namely N-(pyridine-4-ylmethyl)pyridine-3-amine, synthesized according to a literature procedure (Lee et al., 2013). Herein, we report the of the title compound.
2. Structural commentary
The LCl2]·0.5CHCl3}n, L = N-(pyridine-4-ylmethyl)pyridine-3-amine, C11H11N3, comprises one HgII ion, one L ligand, two chloride anions and one half-molecule of chloroform. The solvent molecule is disordered over two orientations of equal occupancy about the crystallographic twofold rotation axis. As shown in Fig. 1, the coordination geometry of each HgII ion is highly distorted tetrahedral with two coordination sites being occupied by two pyridine N atoms from two symmetry-related L ligands. The geometry of the HgII ion is completed by the coordination of two chloride ions. The tetrahedral angles around the HgII ion fall in the range of 99.05 (17)–142.96 (7)° (Table 1).
of the title compound, {[HgEach L ligand bridges two HgII ions into an infinite zigzag chain propagating along the b axis (Fig. 2). The separation between the HgII ions through a L ligand in the chain is 8.1033 (6) Å. In the L ligand, the Cpy—N—C—Cpy torsion angle is −70.9 (7)° while the dihedral angle between two terminal pyridine ring planes is 85.0 (2)°. The conformation of the L ligand, along with the the Npy—Hg—Npy coordination angle [99.05 (17)°], may induce the zigzag topology of the chain.
3. Supramolecular features
In the crystal, adjacent zigzag chains are linked by intermolecular N—H⋯Cl hydrogen bonds and weak intermolecular C—H⋯π interactions (Table 2), forming a layer extending parallel to the bc plane (Figs. 2 and 3). Furthermore, neighboring layers are packed by C—H⋯Cl hydrogen bonds (Table 2), resulting in the formation of a three-dimensional supramolecular network (Fig. 3). This three-dimensional network is further stabilized by C—Cl⋯π interactions (Chifotides & Dunbar, 2013; Matter et al., 2009) between the solvent chloroform molecules and the pyridine rings of L with Cl4⋯Cg2 = 3.442 (11) Å, C12—Cl4⋯Cg2 = 170.7 (8)°, Cl5⋯Cg2iv = 3.626 (13) Å and C12—Cl5⋯Cg2iv 144.1 (8)° [yellow dashed lines in Figs. 1, 2 and 3; Cg2 is the centroid of the N2/C7–C11 ring; symmetry code: (iv) −x, y, −z + ]. In addition, weak intermolecular Cl⋯Cl contacts between the solvent chloroform molecule and the coordinating chloride anion [Cl1⋯Cl3v = 3.320 (5) Å, Hg1—Cl1⋯Cl3v = 126.70 (14) and Cl1⋯Cl3v—C12v = 169.2 (8)°; symmetry code: (v) x + , y + , z] are observed.
4. Synthesis and crystallization
The L ligand was synthesized according to a literature method (Lee et al., 2013). X-ray-quality single crystals of the title compound were obtained by slow diffusion of a methanol solution of HgCl2 into a chloroform solution of the L ligand.
5. Refinement
Crystal data, data collection and structure . A reflection affected by the beamstop was omitted from the final The chloroform molecule is disordered over two sets of sites about a twofold rotation axis with equal occupancy. The C—Cl bond lengths were restrained using the DFIX instructions in SHELXL2014/7 (Sheldrick, 2015). All H atoms were positioned geometrically with d(C—H) = 0.93 Å for Csp2—H, 0.97 Å for methylene C—H, 0.98 Å for methine C—H, and 0.86 Å for amine N—H, and were refined as riding with Uiso(H) = 1.2Ueq(C,N).
details are summarized in Table 3
|
Supporting information
CCDC reference: 1507232
https://doi.org/10.1107/S2056989016015310/sj5509sup1.cif
contains datablocks I, New_Global_Publ_Block. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989016015310/sj5509Isup2.hkl
Data collection: APEX2 (Bruker, 2014); cell
SAINT (Bruker, 2014); data reduction: SAINT (Bruker, 2014); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: DIAMOND (Brandenburg, 2010); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).[HgCl2(C11H11N3)]·0.5CHCl3 | F(000) = 1928 |
Mr = 516.40 | Dx = 2.137 Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71073 Å |
a = 16.6906 (14) Å | Cell parameters from 3870 reflections |
b = 9.1942 (8) Å | θ = 2.0–28.3° |
c = 21.0159 (17) Å | µ = 10.16 mm−1 |
β = 95.501 (2)° | T = 298 K |
V = 3210.2 (5) Å3 | Block, colorless |
Z = 8 | 0.4 × 0.3 × 0.3 mm |
Bruker APEXII CCD area detector diffractometer | 2189 reflections with I > 2σ(I) |
phi and ω scans | Rint = 0.044 |
Absorption correction: multi-scan (SADABS; Bruker, 2014) | θmax = 26.0°, θmin = 2.5° |
Tmin = 0.521, Tmax = 0.928 | h = −12→20 |
8852 measured reflections | k = −11→10 |
3151 independent reflections | l = −24→25 |
Refinement on F2 | 3 restraints |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.033 | H-atom parameters constrained |
wR(F2) = 0.074 | w = 1/[σ2(Fo2) + (0.034P)2] where P = (Fo2 + 2Fc2)/3 |
S = 0.99 | (Δ/σ)max = 0.001 |
3151 reflections | Δρmax = 0.58 e Å−3 |
190 parameters | Δρmin = −0.83 e Å−3 |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
Hg1 | 0.32126 (2) | 0.66479 (3) | 0.10699 (2) | 0.06180 (11) | |
Cl1 | 0.44104 (11) | 0.8055 (2) | 0.11123 (9) | 0.0766 (5) | |
Cl2 | 0.18389 (11) | 0.6629 (2) | 0.06581 (9) | 0.0839 (6) | |
N1 | 0.3676 (3) | 0.4300 (6) | 0.0825 (2) | 0.0548 (13) | |
N2 | 0.1898 (3) | 0.1323 (5) | 0.2816 (2) | 0.0568 (13) | |
N3 | 0.2853 (4) | 0.0648 (6) | 0.0611 (2) | 0.0641 (15) | |
H3 | 0.3015 | −0.0182 | 0.0486 | 0.077* | |
C1 | 0.3176 (4) | 0.3179 (7) | 0.0811 (3) | 0.0522 (15) | |
H1 | 0.2663 | 0.3330 | 0.0938 | 0.063* | |
C2 | 0.4398 (4) | 0.4134 (8) | 0.0648 (3) | 0.0693 (18) | |
H2 | 0.4749 | 0.4922 | 0.0662 | 0.083* | |
C3 | 0.4649 (5) | 0.2790 (10) | 0.0439 (4) | 0.080 (2) | |
H3A | 0.5163 | 0.2687 | 0.0310 | 0.096* | |
C4 | 0.4152 (5) | 0.1641 (8) | 0.0423 (3) | 0.075 (2) | |
H4 | 0.4322 | 0.0742 | 0.0284 | 0.090* | |
C5 | 0.3372 (4) | 0.1798 (7) | 0.0618 (3) | 0.0562 (16) | |
C6 | 0.2052 (4) | 0.0749 (7) | 0.0800 (3) | 0.0615 (17) | |
H6A | 0.1761 | −0.0130 | 0.0667 | 0.074* | |
H6B | 0.1780 | 0.1559 | 0.0576 | 0.074* | |
C7 | 0.2007 (4) | 0.0955 (7) | 0.1513 (2) | 0.0499 (15) | |
C8 | 0.1386 (4) | 0.1686 (7) | 0.1738 (3) | 0.0636 (17) | |
H8 | 0.0986 | 0.2093 | 0.1454 | 0.076* | |
C9 | 0.1348 (4) | 0.1821 (7) | 0.2375 (3) | 0.0664 (18) | |
H9 | 0.0904 | 0.2298 | 0.2512 | 0.080* | |
C10 | 0.2502 (4) | 0.0629 (7) | 0.2600 (3) | 0.0677 (19) | |
H10 | 0.2895 | 0.0249 | 0.2897 | 0.081* | |
C11 | 0.2594 (4) | 0.0424 (7) | 0.1953 (3) | 0.0618 (18) | |
H11 | 0.3040 | −0.0060 | 0.1825 | 0.074* | |
C12 | 0.0095 (13) | −0.2965 (16) | 0.2726 (7) | 0.128 (8) | 0.5 |
H12 | 0.0355 | −0.3356 | 0.3128 | 0.153* | 0.5 |
Cl3 | −0.0016 (4) | −0.4392 (6) | 0.2177 (3) | 0.1288 (19) | 0.5 |
Cl4 | 0.0705 (7) | −0.1706 (11) | 0.2464 (6) | 0.201 (5) | 0.5 |
Cl5 | −0.0803 (8) | −0.2208 (14) | 0.2885 (6) | 0.230 (7) | 0.5 |
U11 | U22 | U33 | U12 | U13 | U23 | |
Hg1 | 0.06149 (17) | 0.07271 (18) | 0.05193 (16) | 0.00720 (15) | 0.00918 (12) | −0.00275 (14) |
Cl1 | 0.0576 (10) | 0.0833 (12) | 0.0887 (13) | 0.0035 (9) | 0.0056 (10) | 0.0198 (10) |
Cl2 | 0.0639 (11) | 0.1104 (15) | 0.0748 (11) | 0.0191 (11) | −0.0065 (9) | −0.0262 (11) |
N1 | 0.052 (3) | 0.069 (3) | 0.044 (3) | 0.012 (3) | 0.006 (3) | −0.001 (2) |
N2 | 0.053 (3) | 0.078 (4) | 0.040 (3) | 0.007 (3) | 0.009 (3) | 0.006 (2) |
N3 | 0.096 (4) | 0.052 (3) | 0.047 (3) | 0.018 (3) | 0.019 (3) | −0.004 (2) |
C1 | 0.053 (4) | 0.063 (4) | 0.041 (3) | 0.017 (3) | 0.007 (3) | −0.001 (3) |
C2 | 0.056 (4) | 0.083 (5) | 0.070 (4) | 0.019 (4) | 0.011 (4) | 0.008 (4) |
C3 | 0.065 (5) | 0.097 (6) | 0.083 (6) | 0.030 (5) | 0.026 (4) | 0.020 (5) |
C4 | 0.099 (6) | 0.072 (5) | 0.057 (4) | 0.032 (5) | 0.027 (4) | 0.010 (4) |
C5 | 0.070 (4) | 0.066 (4) | 0.034 (3) | 0.023 (4) | 0.010 (3) | 0.007 (3) |
C6 | 0.074 (5) | 0.061 (4) | 0.047 (4) | 0.002 (4) | −0.004 (4) | 0.001 (3) |
C7 | 0.061 (4) | 0.053 (3) | 0.036 (3) | 0.000 (3) | 0.002 (3) | 0.006 (3) |
C8 | 0.052 (4) | 0.082 (4) | 0.053 (4) | 0.017 (4) | −0.011 (3) | 0.007 (4) |
C9 | 0.052 (4) | 0.089 (5) | 0.059 (4) | 0.015 (4) | 0.005 (3) | −0.002 (4) |
C10 | 0.065 (4) | 0.083 (5) | 0.055 (4) | 0.018 (4) | 0.004 (4) | 0.017 (3) |
C11 | 0.061 (4) | 0.083 (5) | 0.042 (3) | 0.029 (4) | 0.008 (3) | 0.003 (3) |
C12 | 0.18 (2) | 0.108 (14) | 0.098 (18) | 0.000 (18) | 0.04 (2) | −0.024 (10) |
Cl3 | 0.147 (5) | 0.100 (3) | 0.135 (4) | −0.006 (4) | −0.011 (5) | −0.026 (3) |
Cl4 | 0.208 (10) | 0.167 (7) | 0.234 (11) | −0.120 (7) | 0.051 (8) | −0.057 (7) |
Cl5 | 0.184 (9) | 0.242 (12) | 0.281 (15) | −0.077 (9) | 0.110 (10) | −0.150 (11) |
Hg1—N1 | 2.367 (5) | C4—C5 | 1.409 (10) |
Hg1—Cl2 | 2.3718 (19) | C4—H4 | 0.9300 |
Hg1—Cl1 | 2.3759 (18) | C6—C7 | 1.519 (7) |
Hg1—N2i | 2.385 (5) | C6—H6A | 0.9700 |
N1—C2 | 1.303 (8) | C6—H6B | 0.9700 |
N1—C1 | 1.326 (8) | C7—C8 | 1.358 (8) |
N2—C10 | 1.310 (8) | C7—C11 | 1.371 (8) |
N2—C9 | 1.323 (8) | C8—C9 | 1.352 (9) |
N2—Hg1ii | 2.386 (5) | C8—H8 | 0.9300 |
N3—C5 | 1.366 (8) | C9—H9 | 0.9300 |
N3—C6 | 1.434 (8) | C10—C11 | 1.394 (8) |
N3—H3 | 0.8600 | C10—H10 | 0.9300 |
C1—C5 | 1.382 (8) | C11—H11 | 0.9300 |
C1—H1 | 0.9300 | C12—Cl4 | 1.670 (15) |
C2—C3 | 1.389 (11) | C12—Cl5 | 1.713 (17) |
C2—H2 | 0.9300 | C12—Cl3 | 1.746 (13) |
C3—C4 | 1.342 (10) | C12—H12 | 0.9800 |
C3—H3A | 0.9300 | ||
N1—Hg1—Cl2 | 103.82 (14) | C1—C5—C4 | 115.5 (7) |
N1—Hg1—Cl1 | 102.31 (14) | N3—C6—C7 | 114.6 (5) |
Cl2—Hg1—Cl1 | 142.96 (7) | N3—C6—H6A | 108.6 |
N1—Hg1—N2i | 99.05 (17) | C7—C6—H6A | 108.6 |
Cl2—Hg1—N2i | 101.20 (14) | N3—C6—H6B | 108.6 |
Cl1—Hg1—N2i | 100.11 (13) | C7—C6—H6B | 108.6 |
C2—N1—C1 | 120.0 (6) | H6A—C6—H6B | 107.6 |
C2—N1—Hg1 | 120.0 (5) | C8—C7—C11 | 117.5 (5) |
C1—N1—Hg1 | 119.7 (4) | C8—C7—C6 | 121.0 (5) |
C10—N2—C9 | 115.6 (5) | C11—C7—C6 | 121.5 (6) |
C10—N2—Hg1ii | 122.4 (4) | C9—C8—C7 | 119.9 (6) |
C9—N2—Hg1ii | 122.0 (4) | C9—C8—H8 | 120.0 |
C5—N3—C6 | 123.7 (5) | C7—C8—H8 | 120.0 |
C5—N3—H3 | 118.2 | N2—C9—C8 | 124.5 (6) |
C6—N3—H3 | 118.2 | N2—C9—H9 | 117.7 |
N1—C1—C5 | 123.7 (6) | C8—C9—H9 | 117.7 |
N1—C1—H1 | 118.2 | N2—C10—C11 | 124.3 (6) |
C5—C1—H1 | 118.2 | N2—C10—H10 | 117.8 |
N1—C2—C3 | 120.6 (7) | C11—C10—H10 | 117.8 |
N1—C2—H2 | 119.7 | C7—C11—C10 | 118.1 (6) |
C3—C2—H2 | 119.7 | C7—C11—H11 | 120.9 |
C4—C3—C2 | 120.3 (7) | C10—C11—H11 | 120.9 |
C4—C3—H3A | 119.8 | Cl4—C12—Cl5 | 110.8 (10) |
C2—C3—H3A | 119.8 | Cl4—C12—Cl3 | 109.4 (9) |
C3—C4—C5 | 119.9 (7) | Cl5—C12—Cl3 | 113.3 (11) |
C3—C4—H4 | 120.1 | Cl4—C12—H12 | 107.7 |
C5—C4—H4 | 120.1 | Cl5—C12—H12 | 107.7 |
N3—C5—C1 | 123.1 (6) | Cl3—C12—H12 | 107.7 |
N3—C5—C4 | 121.4 (6) | ||
C2—N1—C1—C5 | 0.3 (9) | N3—C6—C7—C8 | 150.4 (6) |
Hg1—N1—C1—C5 | 174.1 (4) | N3—C6—C7—C11 | −29.1 (9) |
C1—N1—C2—C3 | 0.6 (9) | C11—C7—C8—C9 | −2.3 (10) |
Hg1—N1—C2—C3 | −173.3 (5) | C6—C7—C8—C9 | 178.2 (6) |
N1—C2—C3—C4 | −0.8 (11) | C10—N2—C9—C8 | −1.6 (10) |
C2—C3—C4—C5 | 0.1 (11) | Hg1ii—N2—C9—C8 | 179.0 (5) |
C6—N3—C5—C1 | 0.1 (9) | C7—C8—C9—N2 | 2.3 (11) |
C6—N3—C5—C4 | −179.6 (5) | C9—N2—C10—C11 | 1.1 (10) |
N1—C1—C5—N3 | 179.5 (5) | Hg1ii—N2—C10—C11 | −179.5 (5) |
N1—C1—C5—C4 | −0.8 (9) | C8—C7—C11—C10 | 1.9 (10) |
C3—C4—C5—N3 | −179.7 (6) | C6—C7—C11—C10 | −178.7 (6) |
C3—C4—C5—C1 | 0.6 (9) | N2—C10—C11—C7 | −1.4 (11) |
C5—N3—C6—C7 | −70.9 (7) |
Symmetry codes: (i) −x+1/2, y+1/2, −z+1/2; (ii) −x+1/2, y−1/2, −z+1/2. |
Cg1 is the centroid of the N1/C1–C5 ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H3···Cl2iii | 0.86 | 2.78 | 3.467 (5) | 138 |
C8—H8···Cl1iv | 0.93 | 2.80 | 3.654 (6) | 153 |
C6—H6B···Cg1iii | 0.97 | 2.71 | 3.465 (7) | 135 |
Symmetry codes: (iii) −x+1/2, −y+1/2, −z; (iv) x−1/2, y−1/2, z. |
Acknowledgements
This work was supported by the National Research Foundation of Korea (NRF) project (2015R1D1A3A01020410).
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