catena-Poly[[di­bromidomercury(II)]-μ-3,6-bis­­(2-pyridyl­sulfan­yl)pyridazine-κ²N³:N⁶]

In the title coordination polymer, [HgBr₂(C₁₄H₁₀N₄S₂)]_n, the Hg^II atom is four-coordinated in a distorted tetra­hedral geometry by the two N atoms of the pyridyl groups of different 3,6-bis­(2-pyridyl­sulfan­yl)pyridazine ligands and two Br atoms. The bridging function of the cis ligands leads to a helical chain structure along [100].

Related literature

For metal coordination compounds with 3,6-bis­(2-pyridyl­thio) pyridazine, see: Chen et al. (1996); Mandal et al. (1987, 1988); Song et al. (2011); Woon et al. (1986).

Experimental

Crystal data

• [HgBr₂(C₁₄H₁₀N₄S₂)]

• M_r = 658.78

• Monoclinic, C 2/c

• a = 16.393 (3) Å

• b = 12.4954 (19) Å

• c = 9.7648 (16) Å

• β = 117.444 (3)°

• V = 1775.1 (5) ų

• Z = 4

• Mo Kα radiation

• μ = 13.41 mm⁻¹

• T = 223 K

• 0.55 × 0.30 × 0.26 mm

Data collection

• Rigaku Saturn diffractometer

• Absorption correction: multi-scan (REQAB; Jacobson, 1998) T_min = 0.013, T_max = 0.030

• 5341 measured reflections

• 2013 independent reflections

• 1688 reflections with I > 2σ(I)

• R_int = 0.032

Refinement

• R[F² > 2σ(F²)] = 0.038

• wR(F²) = 0.080

• S = 1.00

• 2013 reflections

• 107 parameters

• H-atom parameters constrained

• Δρ_max = 1.56 e Å⁻³

• Δρ_min = −2.20 e Å⁻³

Data collection: CrystalClear (Rigaku, 2001); cell refinement: CrystalClear; data reduction: CrystalStructure (Rigaku, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.

Supporting information

S1. Comment

In recent years, metal complexes of N-containing heterocyclic flexible thioethers ligands especially attracted considerable interest. The ligand 3,6-bis(2-pyridylthio) pyridazine (PTP) is interesting bridging ligand and is able to act as bridges between metal centers to form dinuclear (Chen et al., 1996; Mandal et al., 1987, 1988; Woon et al., 1986) and coordination polymer (Song et al. 2011). Herein, we report the crystal structure of Hg^II complex (I).

The title complex (I) is one-dimensional chain coordination polymer. Each Hg^II atom is in a distorted tetrahedral geometry with two N atoms from two different PTP ligands and two bromide (Fig. 1). Its structure is isomorphous with HgI₂ complex (Song et al., 2011). Complex (I) has a compressed N—Hg—N angle of 98.8 (2)° and an expanded Br—Hg—Br angle of 140.84 (4)°, whereas for iodide structure the compressed N—Hg—N angle and expanded I—Hg—I angle are 96.6 (2)° and 144.01 (2)° (Song et al., 2011), respectively. As HgI₂ complex (Song et al., 2011), HgBr₂ units of the complex (I) are connected to each other by cis-PTP ligands through the pyridyl nitrogen atoms into a one-dimensional chain along [100] (Fig. 2). The ligand adopts a pronounced syn twist, creating an angle of 15.3 (1)° between the pyridine planes and angles of 83.2 (1)° between the pyridine planes and the pyridazine plane. The two pyridyl groups in PTP are not coplanar, and the bending of the ligand and its coordination at the Hg(II) center result in one-dimensional chains that adopt a helical twist. The isomorphous structure results from tetrahedral coordination geometry Hg^II ions.

Related literature

For metal coordination compounds with 3,6-bis(2-pyridylthio) pyridazine, see: Chen et al. (1996); Mandal et al. (1987, 1988); Song et al. (2011); Woon et al. (1986).

S2. Experimental

The ligand 3,6-bis(2-pyridylthio) pyridazine (PTP) was prepared according to the general procedure reported by Woon et al. (1986). For preparation of the title compound, a solution of HgBr₂ (18.5 mg, 0.05 mmol) in acetone (2 ml) was slowly added to a solution of PTP (15 mg, 0.05 mmol) in CH₃OH (2 ml). The mixture was stirred for 0.5 h at room temperature, and then filtered and kept in the refrigerator (-18 C°). After 48 h, yellow prismatic single-crystals (I) of suitable for X-ray analysis was obtained in 67.2% yield. IR (cm^-1): 3039.81.w, 2368.58w, 1581.62m, 1450.47m, 1427.32m, 1396.46 s, 833.25w, 771.52 s, 632.65w, 578.64w. Anal. Found: C, 25.53; H, 1.51; N, 8.46. Calcd. For C₁₄H₁₀Br₂HgN₄S₂: C, 25.50; H, 1.32; N, 8.50.

S3. Refinement

H atoms were included in calculated positions refined as part of a riding with C—H distances of 0.94Å (aromatic H), and with U_iso= 1.2U_eq(C).

Computing details

Data collection: CrystalClear (Rigaku, 2001); cell refinement: CrystalClear (Rigaku, 2001); data reduction: CrystalStructure (Rigaku, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures

	Fig. 1. The the coordination environment of Hg^II center of complex(I), with atom labels and 30% probability displacement ellipsoids for non-H atoms.
	Fig. 2. Perspective view of the 1-D helical chain structure of complex(I).

catena-Poly[[dibromidomercury(II)]-µ-3,6-bis(2- pyridylsulfanyl)pyridazine-κ²N³:N⁶]

Crystal data

[HgBr2(C14H10N4S2)]	F(000) = 1216
Mr = 658.78	Dx = 2.465 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71075 Å
Hall symbol: -C 2yc	Cell parameters from 2664 reflections
a = 16.393 (3) Å	θ = 3.6–27.5°
b = 12.4954 (19) Å	µ = 13.41 mm^−1
c = 9.7648 (16) Å	T = 223 K
β = 117.444 (3)°	Prism, yellow
V = 1775.1 (5) Å^3	0.55 × 0.30 × 0.26 mm
Z = 4

Data collection

Rigaku Saturn diffractometer	2013 independent reflections
Radiation source: fine-focus sealed tube	1688 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.032
Detector resolution: 14.63 pixels mm^-1	θmax = 27.5°, θmin = 3.6°
ω scans	h = −18→21
Absorption correction: multi-scan (REQAB; Jacobson, 1998)	k = −9→16
Tmin = 0.013, Tmax = 0.030	l = −12→10
5341 measured reflections

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.038	H-atom parameters constrained
wR(F^2) = 0.080	w = 1/[σ^2(Fo^2) + (0.0419P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 1.00	(Δ/σ)max < 0.001
2013 reflections	Δρmax = 1.56 e Å^−3
107 parameters	Δρmin = −2.20 e Å^−3
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.00186 (14)

Special details

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Hg1	0.5000	0.24799 (3)	0.2500	0.03257 (15)
Br1	0.37219 (4)	0.18078 (6)	0.00215 (7)	0.03794 (19)
S1	0.63765 (10)	0.19500 (16)	0.09685 (16)	0.0354 (4)
N1	0.5935 (3)	0.3774 (4)	0.1882 (5)	0.0300 (11)
N2	0.5304 (3)	0.2847 (4)	−0.1745 (5)	0.0282 (11)
C1	0.6470 (3)	0.3344 (5)	0.1311 (6)	0.0272 (13)
C2	0.7060 (4)	0.3982 (7)	0.0995 (7)	0.0438 (18)
H2A	0.7442	0.3669	0.0625	0.053*
C3	0.7083 (4)	0.5050 (8)	0.1218 (7)	0.051 (2)
H3	0.7469	0.5486	0.0984	0.062*
C4	0.6537 (4)	0.5493 (6)	0.1790 (7)	0.0440 (16)
H4	0.6530	0.6236	0.1937	0.053*
C5	0.6000 (4)	0.4815 (6)	0.2142 (8)	0.0427 (16)
H5	0.5657	0.5113	0.2598	0.051*
C6	0.5593 (3)	0.1942 (5)	−0.1028 (6)	0.0284 (12)
C7	0.5306 (4)	0.0926 (6)	−0.1734 (7)	0.0411 (15)
H7	0.5525	0.0287	−0.1176	0.049*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Hg1	0.0342 (2)	0.0283 (2)	0.0378 (2)	0.000	0.01890 (15)	0.000
Br1	0.0372 (3)	0.0317 (4)	0.0401 (3)	−0.0041 (3)	0.0137 (3)	0.0007 (3)
S1	0.0382 (7)	0.0330 (10)	0.0332 (7)	0.0155 (7)	0.0148 (6)	0.0078 (7)
N1	0.029 (2)	0.021 (3)	0.041 (2)	−0.003 (2)	0.018 (2)	0.000 (2)
N2	0.030 (2)	0.019 (3)	0.031 (2)	0.000 (2)	0.0111 (19)	−0.004 (2)
C1	0.018 (2)	0.035 (4)	0.025 (2)	0.003 (2)	0.007 (2)	0.008 (2)
C2	0.032 (3)	0.063 (6)	0.043 (3)	−0.013 (3)	0.023 (3)	−0.009 (3)
C3	0.050 (4)	0.059 (6)	0.045 (3)	−0.032 (4)	0.022 (3)	−0.004 (4)
C4	0.045 (3)	0.029 (4)	0.054 (4)	−0.012 (3)	0.019 (3)	−0.002 (3)
C5	0.041 (3)	0.028 (4)	0.066 (4)	−0.003 (3)	0.030 (3)	−0.004 (3)
C6	0.028 (3)	0.026 (4)	0.036 (3)	0.008 (2)	0.019 (2)	0.008 (3)
C7	0.066 (4)	0.015 (3)	0.048 (3)	0.005 (3)	0.030 (3)	0.010 (3)

Geometric parameters (Å, º)

Hg1—N1	2.485 (5)	C2—C3	1.350 (12)
Hg1—N1^i	2.485 (5)	C2—H2A	0.9400
Hg1—Br1	2.5056 (6)	C3—C4	1.371 (10)
Hg1—Br1^i	2.5056 (6)	C3—H3	0.9400
S1—C1	1.767 (7)	C4—C5	1.373 (9)
S1—C6	1.773 (5)	C4—H4	0.9400
N1—C5	1.321 (9)	C5—H5	0.9400
N1—C1	1.349 (7)	C6—C7	1.417 (9)
N2—C6	1.299 (8)	C7—C7^ii	1.365 (12)
N2—N2^ii	1.347 (9)	C7—H7	0.9400
C1—C2	1.394 (9)
N1—Hg1—N1^i	98.8 (2)	C1—C2—H2A	120.0
N1—Hg1—Br1	108.55 (10)	C2—C3—C4	119.4 (6)
N1^i—Hg1—Br1	96.77 (10)	C2—C3—H3	120.3
N1—Hg1—Br1^i	96.77 (10)	C4—C3—H3	120.3
N1^i—Hg1—Br1^i	108.55 (10)	C3—C4—C5	117.8 (7)
Br1—Hg1—Br1^i	140.84 (4)	C3—C4—H4	121.1
C1—S1—C6	99.7 (3)	C5—C4—H4	121.1
C5—N1—C1	117.4 (5)	N1—C5—C4	124.4 (6)
C5—N1—Hg1	126.8 (4)	N1—C5—H5	117.8
C1—N1—Hg1	115.6 (4)	C4—C5—H5	117.8
C6—N2—N2^ii	119.5 (4)	N2—C6—C7	124.2 (5)
N1—C1—C2	120.9 (6)	N2—C6—S1	119.1 (5)
N1—C1—S1	117.0 (4)	C7—C6—S1	116.7 (5)
C2—C1—S1	122.0 (5)	C7^ii—C7—C6	116.4 (3)
C3—C2—C1	120.0 (6)	C7^ii—C7—H7	121.8
C3—C2—H2A	120.0	C6—C7—H7	121.8
N1^i—Hg1—N1—C5	11.6 (4)	S1—C1—C2—C3	177.5 (5)
Br1—Hg1—N1—C5	111.9 (5)	C1—C2—C3—C4	1.5 (10)
Br1^i—Hg1—N1—C5	−98.4 (5)	C2—C3—C4—C5	1.3 (10)
N1^i—Hg1—N1—C1	−172.8 (4)	C1—N1—C5—C4	3.8 (9)
Br1—Hg1—N1—C1	−72.5 (3)	Hg1—N1—C5—C4	179.3 (5)
Br1^i—Hg1—N1—C1	77.2 (3)	C3—C4—C5—N1	−4.1 (10)
C5—N1—C1—C2	−0.7 (8)	N2^ii—N2—C6—C7	−0.2 (9)
Hg1—N1—C1—C2	−176.7 (4)	N2^ii—N2—C6—S1	−178.8 (5)
C5—N1—C1—S1	180.0 (4)	C1—S1—C6—N2	1.6 (4)
Hg1—N1—C1—S1	3.9 (5)	C1—S1—C6—C7	−177.1 (4)
C6—S1—C1—N1	96.6 (4)	N2—C6—C7—C7^ii	0.6 (10)
C6—S1—C1—C2	−82.8 (5)	S1—C6—C7—C7^ii	179.2 (6)
N1—C1—C2—C3	−1.9 (9)

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