A one-dimensional HgII coordination polymer based on bis­(pyridin-3-ylmeth­yl)sulfane

Moon, S.-H.; Kang, Y.; Park, K.-M.

doi:10.1107/S205698901701619X

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Volume 73| Part 12| December 2017| Pages 1871-1874

https://doi.org/10.1107/S205698901701619X

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A one-dimensional Hg^II coordination polymer based on bis(pyridin-3-ylmethyl)sulfane

Suk-Hee Moon,^a Youngjin Kang ^b ^* and Ki-Min Park ^c ^*

^aDepartment of Food and Nutrition, Kyungnam College of Information and Technology, Busan 47011, Republic of Korea, ^bDivision of Science Education, Kangwon National University, Chuncheon 24341, Republic of Korea, and ^cResearch institute of Natural Science, Gyeongsang National University, Jinju 52828, Republic of Korea
^*Correspondence e-mail: kangy@kangwon.ac.kr, kmpark@gnu.ac.kr

Edited by J. Simpson, University of Otago, New Zealand (Received 5 November 2017; accepted 9 November 2017; online 17 November 2017)

The reaction of mercury(II) chloride with bis(pyridin-3-ylmethyl)sulfane (L, C₁₂H₁₂N₂S) in methanol afforded the title crystalline coordination polymer catena-poly[[dichloridomercury(II)]-μ-bis(pyridin-3-ylmethyl)sulfane-κ²N:N′], [HgCl₂L]_n. The asymmetric unit consists of one Hg^II cation, one L ligand and two chloride anions. Each Hg^II ion is coordinated by two pyridine N atoms from separate L ligands and two chloride anions. The metal adopts a highly distorted tetrahedral geometry, with bond angles about the central atom in the range 97.69 (12)–153.86 (7)°. Each L ligand bridges two Hg^II ions, forming an infinite –(Hg–L)_n– zigzag chain along the b axis, with an Hg⋯Hg separation of 10.3997 (8) Å. In the crystal, adjacent chains are connected by intermolecular C—H⋯Cl hydrogen bonds, together with Hg—Cl⋯π interactions [chloride-to-centroid distance = 3.902 (3) Å], that form between a chloride anion and the one of the pyridine rings of L, generating a two-dimensional layer extending parallel to (101). These layers are further linked by intermolecular C—H⋯π hydrogen bonds, forming a three-dimensional supramolecular network.

Keywords: crystal structure; Hg^II compound; dipyridyl ligand; zigzag coordination polymer; hydrogen bonding; C—H⋯π interactions.

CCDC reference: 1584773

1. Chemical context

The structural topology of coordination polymers generated from the self-assembly of transition metal ions and organic molecules functioning as spacer ligands depends mainly on the structures of the spacer ligands and the coordination geometries adopted by the metal ions. The flexibility, length and coordinating ability of the spacer ligands exert strong influences on the formation of coordination polymers and their resulting diverse topologies (Zheng et al., 2009 ; Leong & Vittal, 2011 ; Liu et al. 2011 ). For this reason, both rigid and flexible dipyridyl-type spacer ligands with strong coordinating ability and functional characteristics have been widely used to construct a variety of coordination polymers with interesting structures and attractive potential applications in material science (Silva et al., 2015 ; Furukawa et al., 2014 ; Wang et al., 2012 ).

Our group has also synthesized the flexible dipyridyl-type ligand bis(pyridine-3-ylmethyl)sulfane (L), and has reported its Ag^I and Co^II coordination polymers (Moon et al., 2017a ,b ). Our continuing interest in the development of coordination polymers based on this ligand led us to investigate a coordination polymer with an Hg^II cation. The reaction of mercury(II) chloride with L (synthesized according to a previously reported procedure: Park et al., 2010 ; Lee et al., 2012 ) afforded the title compound. Herein, we describe its structure, which involves a one-dimensional zigzag-chain.

2. Structural commentary

Fig. 1 shows the molecular structure of the title compound, [HgLCl₂]_n, L = bis(pyridine-3-ylmethyl)sulfane, C₁₂H₁₂N₂S. The asymmetric unit comprises one Hg^II cation, one L ligand and two chloride anions. The Hg^II ion is four-coordinated, binding to two Cl anions and two pyridine N atoms from two separate symmetry-related L ligands, forming a highly distorted tetrahedral geometry (Fig. 1), with the tetrahedral angles falling in the range of 97.69 (12)–153.86 (7)° (Table 1). The S atoms of the L ligands are surprisingly not bound to the soft Hg^II cations. Each L ligand bridges two Hg^II cations, resulting in an infinite zigzag chain propagating along the b-axis direction (Fig. 2). The separation between the Hg^II ions in the chain is 10.3997 (8) Å. In the L ligand, the dihedral angle between the two terminal pyridine rings is 78.52 (18)°, and the flexible thioether moiety [C4–C6–S1–C7–C8] shows a bent arrangement with a gauche--anti configuration [C4—C6—S1—C7 = 71.9 (5)°; C6—S1—C7—C8 = 172.1 (5)°]. The conformation of the L ligand, along with its N_py—Hg—N_py coordination angle [98.39 (16)°], may induce the zigzag topology of the chain.

Table 1
Selected geometric parameters (Å, °)

Hg1—Cl1	2.3610 (16)	Hg1—N2ⁱ	2.434 (5)
Hg1—Cl2	2.3751 (16)	Hg1—N1	2.436 (5)

Cl1—Hg1—Cl2	153.86 (7)	Cl1—Hg1—N1	97.69 (12)
Cl1—Hg1—N2ⁱ	100.29 (12)	Cl2—Hg1—N1	97.91 (13)
Cl2—Hg1—N2ⁱ	98.03 (12)	N2ⁱ—Hg1—N1	98.39 (16)
Symmetry code: (i) $[-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ .

Figure 1
View of the molecular structure of the title compound, showing the atom-numbering scheme [symmetry codes: (i) −x + $[{1\over 2}]$ , y − $[{1\over 2}]$ , −z + $[{1\over 2}]$ ; (ii) −x + $[{1\over 2}]$ , y + $[{1\over 2}]$ , −z + $[{1\over 2}]$ ]. Displacement ellipsoids are drawn at the 50% probability level.

Figure 2
The polymeric zigzag chain propagating along the b-axis direction. H atoms are omitted for clarity.

3. Supramolecular features

In the crystal structure, adjacent zigzag chains are connected by C10—H10⋯Cl1 hydrogen bonds (Fig. 3, Table 2) and Hg—Cl⋯π interactions (Chifotides & Dunbar, 2013 ; Matter et al., 2009 ) between the chloride anions and the pyridine rings of L with Cl2⋯Cg1^iv = 3.902 (3) Å and Hg1—Cl2⋯Cg1^iv = 77.21 (6)° [Fig. 3; Cg1 is the centroid of the N1/C1–C5 ring; symmetry code: (iv) −x + 1, −y + 1, −z + 1], generating layers extending parallel to (101). Neighboring layers are linked by C2—H2⋯Cg2 hydrogen bonds (Table 2; Fig. 4), resulting in the formation of a three-dimensional supramolecular network.

Table 2
Hydrogen-bond geometry (Å, °)

Cg2 is the centroid of the N2/C8–C12 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C10—H10⋯Cl1ⁱⁱ	0.93	2.80	3.526 (6)	136
C2—H2⋯Cg2ⁱⁱⁱ	0.93	2.89	3.689 (7)	145
Symmetry codes: (ii) -x, -y+1, -z; (iii) -x, -y+1, -z+1.

Figure 3
The layer formed through intermolecular C–H⋯Cl hydrogen bonds (yellow dashed lines) and Hg—Cl⋯π interactions (black dashed lines) between the zigzag chains. H atoms not involved in intermolecular interactions are omitted for clarity.

Figure 4
The three-dimensional supramolecular network generated by intermolecular C—H⋯π interactions (yellow dashed lines) between the layers of polymer chains. H atoms not involved in intermolecular interactions are omitted for clarity.

4. Database survey

A search of the Cambridge Structural Database (Version 5.38, update May 2017; Groom et al., 2016 ) for the title ligand (L) gave three hits. Two (REJCAL, RENHOI; Hanton et al., 2006 ) are copper(I) iodide coordination polymers adopting staircase- and loop-type structures, respectively. The other (EXEZOW; Seo et al., 2003 ) is a cyclic dimer-type silver(I) BF₄ complex. Recently, our group has also reported the crystal structures of silver(I) (Moon et al., 2017a) and cobalt(II) (Moon et al., 2017b) NO₃ coordination polymers that display twisted ribbon- and loop-type topologies, respectively. In these complexes, the flexible thioether moiety (C_py–C–S–C–C_py) of the L ligand adopts a bent arrangement that is similar to that of the Hg^II polymer described here. However, the title compound displays a zigzag topology and is the first example of an Hg^II coordination polymer with the ligand L.

5. Synthesis and crystallization

The L ligand was synthesized according to a literature method (Park et al., 2010; Lee et al., 2012). Crystals of the title compound were obtained by slow evaporation of a methanol solution of L with HgCl₂ in a 1:1 molar ratio.

6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 3. All H atoms were positioned geometrically and refined as riding: C—H = 0.93 Å for Csp²—H and 0.97 Å for methylene C—H with U_iso(H) = 1.2U_eq(C).

Table 3
Experimental details

Crystal data
Chemical formula	[HgCl₂(C₁₂H₁₂N₂S)]
M_r	487.79
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	298
a, b, c (Å)	10.4724 (11), 13.1128 (14), 10.8914 (12)
β (°)	100.1171 (18)
V (Å³)	1472.4 (3)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	10.94
Crystal size (mm)	0.45 × 0.40 × 0.30

Data collection
Diffractometer	Bruker SMART APEX CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2014 )
T_min, T_max	0.447, 0.746
No. of measured, independent and observed [I > 2σ(I)] reflections	8706, 3197, 2413
R_int	0.047
(sin θ/λ)_max (Å⁻¹)	0.639

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.033, 0.076, 1.03
No. of reflections	3197
No. of parameters	163
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.62, −1.62
Computer programs: APEX2 and SAINT (Bruker, 2014), SHELXS97 and SHELXTL (Sheldrick, 2008 ), SHELXL2014 (Sheldrick, 2015 ), DIAMOND (Brandenburg, 2010 ) and publCIF (Westrip, 2010 ).

Supporting information

CCDC reference: 1584773

Crystal structure: contains datablocks I, New_Global_Publ_Block. DOI: https://doi.org/10.1107/S205698901701619X/sj5541sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S205698901701619X/sj5541Isup2.hkl

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2014); cell refinement: 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) and publCIF (Westrip, 2010).

catena-Poly[[dichloridomercury(II)]-µ-bis(pyridin-3-ylmethyl)sulfane-κ²N:N'] top

Crystal data top

[HgCl₂(C₁₂H₁₂N₂S)]	F(000) = 912
M_r = 487.79	D_x = 2.200 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
a = 10.4724 (11) Å	Cell parameters from 9216 reflections
b = 13.1128 (14) Å	θ = 2.5–28.2°
c = 10.8914 (12) Å	µ = 10.94 mm⁻¹
β = 100.1171 (18)°	T = 298 K
V = 1472.4 (3) Å³	Plate, colorless
Z = 4	0.45 × 0.40 × 0.30 mm

Data collection top

Bruker SMART APEX CCD diffractometer	2413 reflections with I > 2σ(I)
φ and ω scans	R_int = 0.047
Absorption correction: multi-scan (SADABS; Bruker, 2014)	θ_max = 27.0°, θ_min = 2.5°
T_min = 0.447, T_max = 0.746	h = −13→11
8706 measured reflections	k = −16→10
3197 independent reflections	l = −13→13

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.033	H-atom parameters constrained
wR(F²) = 0.076	w = 1/[σ²(F_o²) + (0.0315P)²] where P = (F_o² + 2F_c²)/3
S = 1.03	(Δ/σ)_max < 0.001
3197 reflections	Δρ_max = 0.62 e Å⁻³
163 parameters	Δρ_min = −1.62 e Å⁻³

Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Hg1	0.62237 (2)	0.33807 (2)	0.42736 (2)	0.04266 (10)
Cl1	0.54910 (16)	0.36205 (14)	0.21164 (15)	0.0559 (4)
Cl2	0.75516 (17)	0.37587 (15)	0.62207 (16)	0.0633 (5)
S1	−0.06074 (16)	0.35443 (14)	0.33023 (18)	0.0598 (5)
N1	0.4127 (5)	0.3509 (4)	0.4938 (4)	0.0416 (12)
N2	−0.1449 (4)	0.6533 (4)	0.0651 (4)	0.0408 (12)
C1	0.4063 (6)	0.3940 (5)	0.6036 (6)	0.0467 (15)
H1	0.4823	0.4178	0.6525	0.056*
C2	0.2918 (7)	0.4044 (5)	0.6469 (6)	0.0551 (17)
H2	0.2897	0.4384	0.7215	0.066*
C3	0.1800 (7)	0.3642 (5)	0.5789 (7)	0.0537 (17)
H3	0.1018	0.3697	0.6079	0.064*
C4	0.1849 (6)	0.3153 (4)	0.4666 (6)	0.0414 (14)
C5	0.3037 (6)	0.3121 (4)	0.4282 (6)	0.0425 (14)
H5	0.3081	0.2812	0.3523	0.051*
C6	0.0678 (6)	0.2659 (5)	0.3898 (7)	0.0545 (17)
H6A	0.0341	0.2151	0.4405	0.065*
H6B	0.0944	0.2307	0.3201	0.065*
C7	0.0153 (6)	0.4169 (5)	0.2132 (6)	0.0462 (15)
H7A	0.0896	0.4559	0.2536	0.055*
H7B	0.0457	0.3660	0.1605	0.055*
C8	−0.0790 (5)	0.4860 (5)	0.1354 (5)	0.0403 (13)
C9	−0.0627 (5)	0.5903 (4)	0.1356 (5)	0.0379 (13)
H9	0.0090	0.6181	0.1873	0.045*
C10	−0.2482 (6)	0.6139 (5)	−0.0097 (6)	0.0464 (15)
H10	−0.3048	0.6575	−0.0601	0.056*
C11	−0.2726 (6)	0.5132 (5)	−0.0141 (6)	0.0574 (17)
H11	−0.3457	0.4882	−0.0663	0.069*
C12	−0.1897 (6)	0.4473 (5)	0.0583 (6)	0.0503 (16)
H12	−0.2068	0.3776	0.0563	0.060*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Hg1	0.03985 (13)	0.04678 (16)	0.03812 (15)	0.00356 (11)	−0.00208 (9)	−0.00140 (12)
Cl1	0.0515 (9)	0.0733 (12)	0.0385 (9)	0.0022 (8)	−0.0039 (7)	−0.0006 (8)
Cl2	0.0602 (10)	0.0726 (12)	0.0482 (10)	−0.0080 (9)	−0.0154 (8)	−0.0059 (9)
S1	0.0373 (8)	0.0776 (13)	0.0666 (12)	0.0107 (8)	0.0149 (8)	0.0249 (10)
N1	0.041 (3)	0.048 (3)	0.035 (3)	0.011 (2)	0.006 (2)	−0.002 (2)
N2	0.039 (3)	0.042 (3)	0.039 (3)	−0.004 (2)	0.000 (2)	0.002 (2)
C1	0.047 (3)	0.046 (4)	0.046 (4)	−0.003 (3)	0.004 (3)	0.001 (3)
C2	0.063 (4)	0.061 (5)	0.045 (4)	0.004 (3)	0.021 (3)	−0.009 (3)
C3	0.056 (4)	0.053 (4)	0.057 (4)	−0.001 (3)	0.024 (3)	−0.002 (3)
C4	0.043 (3)	0.033 (3)	0.049 (4)	0.011 (2)	0.009 (3)	0.012 (3)
C5	0.044 (3)	0.047 (4)	0.037 (3)	0.010 (3)	0.007 (3)	−0.003 (3)
C6	0.044 (4)	0.047 (4)	0.071 (5)	−0.001 (3)	0.008 (3)	0.017 (3)
C7	0.039 (3)	0.051 (4)	0.051 (4)	0.000 (3)	0.013 (3)	0.006 (3)
C8	0.043 (3)	0.047 (4)	0.031 (3)	0.001 (3)	0.006 (2)	−0.003 (3)
C9	0.032 (3)	0.045 (4)	0.036 (3)	−0.005 (2)	0.003 (2)	−0.002 (3)
C10	0.040 (3)	0.055 (4)	0.039 (4)	−0.005 (3)	−0.006 (3)	0.001 (3)
C11	0.056 (4)	0.055 (4)	0.053 (4)	−0.013 (3)	−0.011 (3)	−0.004 (3)
C12	0.051 (4)	0.040 (4)	0.056 (4)	−0.014 (3)	−0.002 (3)	−0.003 (3)

Geometric parameters (Å, º) top

Hg1—Cl1	2.3610 (16)	C4—C5	1.381 (8)
Hg1—Cl2	2.3751 (16)	C4—C6	1.504 (9)
Hg1—N2ⁱ	2.434 (5)	C5—H5	0.9300
Hg1—N1	2.436 (5)	C6—H6A	0.9700
S1—C6	1.810 (6)	C6—H6B	0.9700
S1—C7	1.813 (6)	C7—C8	1.490 (8)
N1—C5	1.335 (8)	C7—H7A	0.9700
N1—C1	1.336 (7)	C7—H7B	0.9700
N2—C9	1.334 (7)	C8—C9	1.378 (8)
N2—C10	1.339 (7)	C8—C12	1.402 (8)
N2—Hg1ⁱⁱ	2.434 (5)	C9—H9	0.9300
C1—C2	1.370 (8)	C10—C11	1.345 (9)
C1—H1	0.9300	C10—H10	0.9300
C2—C3	1.376 (10)	C11—C12	1.372 (9)
C2—H2	0.9300	C11—H11	0.9300
C3—C4	1.390 (9)	C12—H12	0.9300
C3—H3	0.9300

Cl1—Hg1—Cl2	153.86 (7)	C4—C6—S1	113.9 (4)
Cl1—Hg1—N2ⁱ	100.29 (12)	C4—C6—H6A	108.8
Cl2—Hg1—N2ⁱ	98.03 (12)	S1—C6—H6A	108.8
Cl1—Hg1—N1	97.69 (12)	C4—C6—H6B	108.8
Cl2—Hg1—N1	97.91 (13)	S1—C6—H6B	108.8
N2ⁱ—Hg1—N1	98.39 (16)	H6A—C6—H6B	107.7
C6—S1—C7	98.7 (3)	C8—C7—S1	110.2 (4)
C5—N1—C1	117.9 (5)	C8—C7—H7A	109.6
C5—N1—Hg1	123.0 (4)	S1—C7—H7A	109.6
C1—N1—Hg1	119.0 (4)	C8—C7—H7B	109.6
C9—N2—C10	118.8 (5)	S1—C7—H7B	109.6
C9—N2—Hg1ⁱⁱ	123.3 (4)	H7A—C7—H7B	108.1
C10—N2—Hg1ⁱⁱ	117.9 (4)	C9—C8—C12	116.7 (6)
N1—C1—C2	122.3 (6)	C9—C8—C7	122.2 (5)
N1—C1—H1	118.8	C12—C8—C7	121.0 (6)
C2—C1—H1	118.8	N2—C9—C8	123.1 (5)
C1—C2—C3	119.3 (6)	N2—C9—H9	118.4
C1—C2—H2	120.3	C8—C9—H9	118.4
C3—C2—H2	120.3	N2—C10—C11	121.9 (6)
C2—C3—C4	119.4 (6)	N2—C10—H10	119.0
C2—C3—H3	120.3	C11—C10—H10	119.0
C4—C3—H3	120.3	C10—C11—C12	120.1 (6)
C5—C4—C3	117.0 (6)	C10—C11—H11	120.0
C5—C4—C6	120.6 (6)	C12—C11—H11	120.0
C3—C4—C6	122.4 (6)	C11—C12—C8	119.3 (6)
N1—C5—C4	123.9 (6)	C11—C12—H12	120.4
N1—C5—H5	118.1	C8—C12—H12	120.4
C4—C5—H5	118.1

C5—N1—C1—C2	−3.7 (9)	C6—S1—C7—C8	172.1 (5)
Hg1—N1—C1—C2	179.6 (5)	S1—C7—C8—C9	114.8 (5)
N1—C1—C2—C3	3.8 (10)	S1—C7—C8—C12	−65.0 (7)
C1—C2—C3—C4	−1.1 (10)	C10—N2—C9—C8	−0.1 (8)
C2—C3—C4—C5	−1.4 (9)	Hg1ⁱⁱ—N2—C9—C8	176.9 (4)
C2—C3—C4—C6	177.5 (6)	C12—C8—C9—N2	−1.4 (9)
C1—N1—C5—C4	0.9 (9)	C7—C8—C9—N2	178.9 (5)
Hg1—N1—C5—C4	177.5 (4)	C9—N2—C10—C11	1.2 (9)
C3—C4—C5—N1	1.6 (9)	Hg1ⁱⁱ—N2—C10—C11	−175.9 (5)
C6—C4—C5—N1	−177.4 (5)	N2—C10—C11—C12	−0.7 (10)
C5—C4—C6—S1	−117.0 (5)	C10—C11—C12—C8	−0.8 (10)
C3—C4—C6—S1	64.1 (7)	C9—C8—C12—C11	1.8 (9)
C7—S1—C6—C4	71.9 (5)	C7—C8—C12—C11	−178.5 (6)

Symmetry codes: (i) −x+1/2, y−1/2, −z+1/2; (ii) −x+1/2, y+1/2, −z+1/2.

Hydrogen-bond geometry (Å, º) top

Cg2 is the centroid of the N2/C8–C12 ring.

D—H···A	D—H	H···A	D···A	D—H···A
C10—H10···Cl1ⁱⁱⁱ	0.93	2.80	3.526 (6)	136
C2—H2···Cg2^iv	0.93	2.89	3.689 (7)	145

Symmetry codes: (iii) −x, −y+1, −z; (iv) −x, −y+1, −z+1.

Funding information

This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2015R1D1A3A01020410) and a 2017 Research Grant from Kangwon National University (No. 520170312).

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