catena-Poly[[dichloridozinc(II)]-μ-1,1′-(hexane-1,6-di­yl)diimidazole-κ2N3:N3′]

Bao, W.-L.

doi:10.1107/S1600536809037696

metal-organic compounds

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ISSN: 2056-9890

Volume 65| Part 10| October 2009| Page m1239

doi:10.1107/S1600536809037696

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catena-Poly[[dichloridozinc(II)]-μ-1,1′-(hexane-1,6-diyl)diimidazole-κ²N³:N^3′]

Wen-Li Bao ^a ^*

^aCriminal Investigation Department, Jilin Public Security Academy, Changchun 130117, People's Republic of China
^*Correspondence e-mail: ll_bao@yahoo.com.cn

(Received 9 September 2009; accepted 17 September 2009; online 26 September 2009)

In the structure of the polymeric title compound, [ZnCl₂(C₁₂H₁₈N₄)]_n or [ZnCl₂(L)]_n, where L = 1,1′-(hexane-1,6-diyl)diimidazole, the Zn^II centre is coordinated by two N atoms of two different L ligands and by two chloride anions in a distorted tetrahedral geometry. The organic ligand links adjacent metals to form a polymeric chain along the c axis. The chains are further connected into layers parallel to the bc plane by intermolecular C—H⋯Cl hydrogen bonds. Two C atoms of the central hexyl chain are disordered over two positions with site-occupancy factors of 0.5.

Related literature

For general background on coordination polymers, see: Batten & Robson (1998 ). For a related structure, see: Yang et al. (2008 ).

Experimental

Crystal data

[ZnCl₂(C₁₂H₁₈N₄)]
M_r = 354.57
Orthorhombic, P b c a
a = 11.255 (6) Å
b = 11.713 (8) Å
c = 23.653 (15) Å
V = 3118 (3) Å³
Z = 8
Cu Kα radiation
μ = 5.27 mm⁻¹
T = 293 K
0.31 × 0.25 × 0.22 mm

Data collection

Oxford Diffraction Gemini R Ultra diffractometer
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.]$ ) T_min = 0.56, T_max = 0.85
21446 measured reflections
2778 independent reflections
2080 reflections with I > 2σ(I)
R_int = 0.053

Refinement

R[F² > 2σ(F²)] = 0.038
wR(F²) = 0.106
S = 1.03
2778 reflections
190 parameters
2 restraints
H-atom parameters constrained
Δρ_max = 0.24 e Å⁻³
Δρ_min = −0.39 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C3—H3⋯Cl1ⁱ	0.93	2.77	3.698 (5)	176
Symmetry code: (i) $[-x+{\script{1\over 2}}, y-{\script{1\over 2}}, z]$ .

Data collection: CrysAlis CCD (Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.]$ ); cell refinement: CrysAlis RED (Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.]$ ); data reduction: CrysAlis RED; 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

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809037696/rz2360sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809037696/rz2360Isup2.hkl

checkCIF report

Comment top

The design and synthesis of metal-organic coordination polymers are of great interest due to their tremendous potential applications (Batten & Robson, 1998). The selection of the ligands is extremely important because changing their geometries can control the topologies of the resulting coordination frameworks. So far, the rigid rod-like spacer 4,4'-bipyridine is well known in the design of metal-organic polymers. However, flexible N-donor ligands such as 1,1'-(hexane-1,6-diyl)diimidazole (L) have not been so well explored (Yang et al., 2008).

The asymmetric unit of the title compound comprises a zinc(II) cation, a 1,1'-(hexane-1,6-diyl)diimidazole ligand, and two chloride anions (Fig. 1). The metal centre is coordinated by two N atoms of two different L ligands, and two Cl anions in a distorted tetrahedral geometry. The C4 and C5 carbon atoms of the hexyl chain are disordered over two positions with site occupancy factors of 0.5. The organic ligand links metal centers at (0.5-x, 1.-y, 0.5+z) and (0.5-x, 1.-y, -0.5+z) to form a polymeric one-dimensional chain (Fig. 2). Adjacent chains are connected by C—H···Cl hydrogen bonds (Table 1) into layers parallel to the bc plane.

Related literature top

For general background on coordination polymers, see: Batten & Robson (1998). For a related structure, see: Yang et al. (2008).

For related literature, see: Bruker (1998).

Experimental top

Zinc chloride (0.5 mmol) and L (0.5 mmol) were placed in water (12 ml), and triethylamine was added until the pH value of the solution was 5.5. The solution was heated in a 23-ml Teflon-lined stainless-steel autoclave at 450 K for 3 days. The autoclave was allowed to cool to room temperature over several hours. Colourless blocks were isolated in about 48% yield.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell refinement: CrysAlis RED (Oxford Diffraction, 2006); data reduction: CrysAlis RED (Oxford Diffraction, 2006); 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 top

	Fig. 1. The asymmetric unit of the title compound, showing the atomic numbering scheme and displacement ellipsoids drawn at the 30% probability level. Only one component of the disordered carbon atoms is shown. [Symmetry code: (i) 1/2-x, 1-y, 1/2+z].
	Fig. 2. View of the polymeric chain in the title compound. H atoms are omitted for clarity.

catena-Poly[[dichloridozinc(II)]-µ-1,1'-(hexane-1,6- diyl)diimidazole-κ²N³:N^3'] top

Crystal data top

[ZnCl₂(C₁₂H₁₈N₄)]	F(000) = 1456
M_r = 354.57	D_x = 1.511 Mg m⁻³
Orthorhombic, Pbca	Cu Kα radiation, λ = 1.54184 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 2778 reflections
a = 11.255 (6) Å	θ = 3.1–67.2°
b = 11.713 (8) Å	µ = 5.27 mm⁻¹
c = 23.653 (15) Å	T = 293 K
V = 3118 (3) Å³	Block, colourless
Z = 8	0.31 × 0.25 × 0.22 mm

Data collection top

Oxford Diffraction Gemini R Ultra diffractometer	2778 independent reflections
Radiation source: fine-focus sealed tube	2080 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.053
Detector resolution: 10.0 pixels mm^-1	θ_max = 67.2°, θ_min = 5.4°
ω scans	h = −12→13
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006)	k = −13→12
T_min = 0.56, T_max = 0.85	l = −28→27
21446 measured reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.038	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.106	H-atom parameters constrained
S = 1.03	w = 1/[σ²(F_o²) + (0.0617P)² + 0.9261P] where P = (F_o² + 2F_c²)/3
2778 reflections	(Δ/σ)_max = 0.001
190 parameters	Δρ_max = 0.24 e Å⁻³
2 restraints	Δρ_min = −0.39 e Å⁻³

Crystal data top

[ZnCl₂(C₁₂H₁₈N₄)]	V = 3118 (3) Å³
M_r = 354.57	Z = 8
Orthorhombic, Pbca	Cu Kα radiation
a = 11.255 (6) Å	µ = 5.27 mm⁻¹
b = 11.713 (8) Å	T = 293 K
c = 23.653 (15) Å	0.31 × 0.25 × 0.22 mm

Data collection top

Oxford Diffraction Gemini R Ultra diffractometer	2778 independent reflections
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006)	2080 reflections with I > 2σ(I)
T_min = 0.56, T_max = 0.85	R_int = 0.053
21446 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.038	2 restraints
wR(F²) = 0.106	H-atom parameters constrained
S = 1.03	Δρ_max = 0.24 e Å⁻³
2778 reflections	Δρ_min = −0.39 e Å⁻³
190 parameters

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.

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 > 2sigma(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 (Å²) top

	x	y	z	U_iso*/U_eq	Occ. (<1)
C1	0.4404 (3)	0.8003 (3)	0.51805 (15)	0.0642 (9)
H1	0.4892	0.8643	0.5167	0.077*
C2	0.4434 (4)	0.7132 (4)	0.48146 (17)	0.0805 (12)
H2	0.4927	0.7061	0.4501	0.097*
C3	0.3080 (4)	0.6823 (4)	0.54427 (16)	0.0786 (12)
H3	0.2460	0.6482	0.5640	0.094*
C4	0.3724 (8)	0.5226 (7)	0.4718 (3)	0.0589 (17)	0.50
H4A	0.4425	0.5193	0.4480	0.071*	0.50
H4B	0.3766	0.4621	0.4998	0.071*	0.50
C5	0.2614 (8)	0.5143 (8)	0.4375 (4)	0.068 (2)	0.50
H5A	0.2580	0.5744	0.4094	0.082*	0.50
H5B	0.1916	0.5192	0.4615	0.082*	0.50
C4'	0.2942 (11)	0.5275 (8)	0.4825 (4)	0.088 (3)	0.50
H4'1	0.3111	0.4674	0.5095	0.105*	0.50
H4'2	0.2091	0.5410	0.4823	0.105*	0.50
C5'	0.3341 (11)	0.4935 (10)	0.4261 (4)	0.102 (4)	0.50
H5'1	0.4191	0.4801	0.4267	0.122*	0.50
H5'2	0.3183	0.5547	0.3995	0.122*	0.50
C6	0.2708 (5)	0.3860 (4)	0.40691 (19)	0.0887 (14)
H6A	0.2973	0.3341	0.4363	0.106*
H6B	0.1898	0.3641	0.3980	0.106*
C7	0.3336 (4)	0.4423 (4)	0.3080 (2)	0.0847 (13)
H7A	0.3863	0.4186	0.2778	0.102*
H7B	0.3618	0.5156	0.3217	0.102*
C8	0.3429 (4)	0.3571 (4)	0.3554 (2)	0.0870 (13)
H8A	0.3178	0.2831	0.3415	0.104*
H8B	0.4257	0.3506	0.3664	0.104*
C9	0.2099 (4)	0.4585 (3)	0.28368 (16)	0.0683 (10)
H9A	0.1563	0.4816	0.3137	0.082*
H9B	0.2119	0.5193	0.2559	0.082*
C10	0.2002 (3)	0.3110 (3)	0.20743 (14)	0.0615 (9)
H10	0.2583	0.3444	0.1849	0.074*
C11	0.0662 (3)	0.1975 (3)	0.23820 (14)	0.0592 (8)
H11	0.0137	0.1364	0.2407	0.071*
C12	0.0775 (3)	0.2814 (3)	0.27673 (14)	0.0615 (8)
H12	0.0352	0.2887	0.3103	0.074*
Zn1	0.31792 (3)	0.87724 (3)	0.625633 (16)	0.04733 (16)
Cl1	0.43448 (8)	1.03207 (8)	0.61904 (4)	0.0671 (2)
Cl2	0.12350 (7)	0.91670 (9)	0.63202 (3)	0.0642 (2)
N1	0.3546 (2)	0.7805 (2)	0.55749 (10)	0.0532 (6)
N2	0.3600 (5)	0.6368 (3)	0.49914 (15)	0.0942 (13)
N3	0.1635 (3)	0.3541 (2)	0.25686 (11)	0.0557 (7)
N4	0.1445 (2)	0.2161 (3)	0.19457 (10)	0.0533 (6)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0628 (19)	0.069 (2)	0.061 (2)	0.0015 (17)	0.0093 (16)	−0.0059 (16)
C2	0.099 (3)	0.080 (3)	0.062 (2)	0.024 (3)	0.011 (2)	−0.012 (2)
C3	0.121 (3)	0.058 (2)	0.057 (2)	−0.023 (2)	0.008 (2)	−0.0031 (17)
C4	0.063 (4)	0.060 (4)	0.053 (4)	0.013 (4)	0.005 (4)	−0.006 (3)
C5	0.065 (5)	0.091 (6)	0.050 (4)	0.025 (4)	0.000 (4)	0.005 (4)
C4'	0.107 (8)	0.073 (6)	0.084 (7)	−0.017 (6)	0.023 (6)	−0.022 (5)
C5'	0.089 (7)	0.101 (8)	0.116 (8)	−0.031 (6)	0.030 (6)	−0.072 (7)
C6	0.123 (4)	0.074 (3)	0.069 (3)	−0.021 (3)	−0.019 (2)	−0.0079 (19)
C7	0.078 (3)	0.090 (3)	0.087 (3)	−0.021 (2)	0.015 (2)	−0.008 (2)
C8	0.064 (2)	0.095 (3)	0.103 (3)	−0.007 (2)	−0.012 (2)	−0.003 (3)
C9	0.089 (3)	0.052 (2)	0.063 (2)	−0.0029 (19)	0.0126 (18)	−0.0050 (15)
C10	0.073 (2)	0.062 (2)	0.0498 (17)	−0.0024 (18)	0.0185 (15)	0.0018 (15)
C11	0.0557 (18)	0.062 (2)	0.0603 (19)	−0.0009 (16)	0.0095 (15)	0.0014 (15)
C12	0.0626 (19)	0.070 (2)	0.0517 (18)	0.0045 (19)	0.0181 (15)	−0.0010 (15)
Zn1	0.0504 (3)	0.0487 (3)	0.0429 (2)	0.00272 (17)	−0.00423 (16)	−0.00345 (15)
Cl1	0.0643 (5)	0.0595 (5)	0.0776 (5)	−0.0137 (4)	−0.0092 (4)	−0.0075 (4)
Cl2	0.0480 (4)	0.0808 (6)	0.0637 (5)	0.0066 (4)	−0.0064 (3)	−0.0068 (4)
N1	0.0620 (15)	0.0520 (16)	0.0457 (13)	−0.0003 (13)	0.0016 (11)	−0.0028 (11)
N2	0.176 (4)	0.0519 (18)	0.0544 (18)	0.001 (2)	0.001 (2)	−0.0125 (14)
N3	0.0665 (16)	0.0536 (16)	0.0470 (14)	0.0053 (13)	0.0101 (12)	−0.0004 (11)
N4	0.0555 (14)	0.0562 (17)	0.0481 (13)	0.0054 (13)	0.0080 (11)	0.0016 (11)

Geometric parameters (Å, º) top

C1—C2	1.338 (6)	C6—H6B	0.9700
C1—N1	1.362 (4)	C7—C8	1.505 (7)
C1—H1	0.9300	C7—C9	1.519 (6)
C2—N2	1.362 (6)	C7—H7A	0.9700
C2—H2	0.9300	C7—H7B	0.9700
C3—N1	1.302 (5)	C8—H8A	0.9700
C3—N2	1.329 (6)	C8—H8B	0.9700
C3—H3	0.9300	C9—N3	1.473 (5)
C4—C5	1.492 (12)	C9—H9A	0.9700
C4—N2	1.493 (8)	C9—H9B	0.9700
C4—H4A	0.9700	C10—N4	1.312 (5)
C4—H4B	0.9700	C10—N3	1.339 (4)
C5—C6	1.672 (10)	C10—H10	0.9300
C5—H5A	0.9700	C11—C12	1.346 (5)
C5—H5B	0.9700	C11—N4	1.374 (4)
C4'—C5'	1.464 (8)	C11—H11	0.9300
C4'—N2	1.531 (7)	C12—N3	1.372 (5)
C4'—H4'1	0.9700	C12—H12	0.9300
C4'—H4'2	0.9700	Zn1—N4ⁱ	2.008 (3)
C5'—C6	1.516 (10)	Zn1—N1	2.013 (3)
C5'—H5'1	0.9700	Zn1—Cl2	2.2415 (13)
C5'—H5'2	0.9700	Zn1—Cl1	2.2438 (12)
C6—C8	1.502 (7)	N4—Zn1ⁱⁱ	2.008 (3)
C6—H6A	0.9700

C2—C1—N1	109.3 (4)	C8—C7—H7B	108.4
C2—C1—H1	125.3	C9—C7—H7B	108.4
N1—C1—H1	125.3	H7A—C7—H7B	107.5
C1—C2—N2	106.5 (4)	C6—C8—C7	114.6 (4)
C1—C2—H2	126.7	C6—C8—H8A	108.6
N2—C2—H2	126.7	C7—C8—H8A	108.6
N1—C3—N2	111.7 (4)	C6—C8—H8B	108.6
N1—C3—H3	124.1	C7—C8—H8B	108.6
N2—C3—H3	124.1	H8A—C8—H8B	107.6
C5—C4—N2	102.4 (6)	N3—C9—C7	112.7 (3)
C5—C4—H4A	111.3	N3—C9—H9A	109.1
N2—C4—H4A	111.3	C7—C9—H9A	109.1
C5—C4—H4B	111.3	N3—C9—H9B	109.1
N2—C4—H4B	111.3	C7—C9—H9B	109.1
H4A—C4—H4B	109.2	H9A—C9—H9B	107.8
C4—C5—C6	103.9 (6)	N4—C10—N3	112.0 (3)
C4—C5—H5A	111.0	N4—C10—H10	124.0
C6—C5—H5A	111.0	N3—C10—H10	124.0
C4—C5—H5B	111.0	C12—C11—N4	109.4 (3)
C6—C5—H5B	111.0	C12—C11—H11	125.3
H5A—C5—H5B	109.0	N4—C11—H11	125.3
C5'—C4'—N2	108.3 (7)	C11—C12—N3	106.7 (3)
C5'—C4'—H4'1	110.0	C11—C12—H12	126.6
N2—C4'—H4'1	110.0	N3—C12—H12	126.6
C5'—C4'—H4'2	110.0	N4ⁱ—Zn1—N1	107.47 (11)
N2—C4'—H4'2	110.0	N4ⁱ—Zn1—Cl2	105.25 (8)
H4'1—C4'—H4'2	108.4	N1—Zn1—Cl2	111.74 (8)
C4'—C5'—C6	110.8 (7)	N4ⁱ—Zn1—Cl1	111.93 (9)
C4'—C5'—H5'1	109.5	N1—Zn1—Cl1	106.23 (9)
C6—C5'—H5'1	109.5	Cl2—Zn1—Cl1	114.13 (5)
C4'—C5'—H5'2	109.5	C3—N1—C1	105.8 (3)
C6—C5'—H5'2	109.5	C3—N1—Zn1	127.4 (3)
H5'1—C5'—H5'2	108.1	C1—N1—Zn1	126.7 (2)
C8—C6—C5'	100.1 (5)	C3—N2—C2	106.7 (3)
C8—C6—C5	126.0 (5)	C3—N2—C4	138.5 (5)
C8—C6—H6A	105.8	C2—N2—C4	113.0 (5)
C5'—C6—H6A	99.3	C3—N2—C4'	109.2 (5)
C5—C6—H6A	105.8	C2—N2—C4'	143.5 (5)
C8—C6—H6B	105.8	C10—N3—C12	106.5 (3)
C5'—C6—H6B	136.6	C10—N3—C9	125.4 (3)
C5—C6—H6B	105.8	C12—N3—C9	128.1 (3)
H6A—C6—H6B	106.2	C10—N4—C11	105.5 (3)
C8—C7—C9	115.4 (4)	C10—N4—Zn1ⁱⁱ	123.3 (2)
C8—C7—H7A	108.4	C11—N4—Zn1ⁱⁱ	131.2 (3)
C9—C7—H7A	108.4

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C3—H3···Cl1ⁱⁱⁱ	0.93	2.77	3.698 (5)	176

Symmetry code: (iii) −x+1/2, y−1/2, z.

Experimental details

Crystal data
Chemical formula	[ZnCl₂(C₁₂H₁₈N₄)]
M_r	354.57
Crystal system, space group	Orthorhombic, Pbca
Temperature (K)	293
a, b, c (Å)	11.255 (6), 11.713 (8), 23.653 (15)
V (Å³)	3118 (3)
Z	8
Radiation type	Cu Kα
µ (mm⁻¹)	5.27
Crystal size (mm)	0.31 × 0.25 × 0.22

Data collection
Diffractometer	Oxford Diffraction Gemini R Ultra diffractometer
Absorption correction	Multi-scan (CrysAlis RED; Oxford Diffraction, 2006)
T_min, T_max	0.56, 0.85
No. of measured, independent and observed [I > 2σ(I)] reflections	21446, 2778, 2080
R_int	0.053
(sin θ/λ)_max (Å⁻¹)	0.598

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.038, 0.106, 1.03
No. of reflections	2778
No. of parameters	190
No. of restraints	2
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.24, −0.39

Computer programs: CrysAlis CCD (Oxford Diffraction, 2006), CrysAlis RED (Oxford Diffraction, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C3—H3···Cl1ⁱ	0.93	2.77	3.698 (5)	176

Symmetry code: (i) −x+1/2, y−1/2, z.

Acknowledgements

The author thanks the Jilin Public Security Academy for supporting this work.

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