Bis[μ-1,3-bis(4,5-dihydroimidazol-2-yl)benzene-κ2N:N′]bis[dichloridozinc(II)] N,N′-dimethylformamide disolvate

Cheng, L.; Zhang, Y.-W.; Sun, Y.-Y.; Zhang, G.

doi:10.1107/S1600536808027773

metal-organic compounds

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ISSN: 2056-9890

Volume 64| Part 10| October 2008| Page m1236

doi:10.1107/S1600536808027773

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Bis[μ-1,3-bis(4,5-dihydroimidazol-2-yl)benzene-κ²N:N′]bis[dichloridozinc(II)] N,N′-dimethylformamide disolvate

Lin Cheng,^a ^* Ya-Wen Zhang,^a Yan-Yan Sun ^a and Gong Zhang ^b

^aDepartment of Chemistry and Chemical Engineering, Southeast University, Nanjing, People's Republic of China, and ^bDepartment of Chemistry and Chemical Engineering, State Key Laboratory of Coordination Chemistry, Nanjing University, Nanjing, People's Republic of China
^*Correspondence e-mail: cep02chl@yahoo.com.cn

(Received 28 August 2008; accepted 29 August 2008; online 6 September 2008)

The title compound, [Zn₂Cl₄(C₁₂H₁₄N₄)₂]·2C₃H₇NO, is located on a centre of inversion with one half of a complex molecule and one dimethylformamide solvent molecule in the asymmetric unit. The Zn^II ion is tetrahedrally coordinated by two organic ligands and two chloride ions. Each organic ligand acts as a bidentate ligand, connecting two Zn^II ions, resulting in a dimeric [2:2] metallamacrocyclic structure. Adjacent molecules are further linked by N—H⋯Cl hydrogen bonds and the solvent is linked to the complex by N—H⋯O hydrogen bonds.

Related literature

For related structures, see: Ren et al. (2004 , 2007 ).

Experimental

Crystal data

[Zn₂Cl₄(C₁₂H₁₄N₄)₂]·2C₃H₇NO
M_r = 847.28
Monoclinic, P 2₁ /c
a = 8.1774 (11) Å
b = 8.5032 (12) Å
c = 27.097 (4) Å
β = 92.890 (2)°
V = 1881.8 (4) Å³
Z = 2
Mo Kα radiation
μ = 1.60 mm⁻¹
T = 123 (2) K
0.43 × 0.27 × 0.20 mm

Data collection

Bruker APEX CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2000 ) T_min = 0.546, T_max = 0.740
13375 measured reflections
3659 independent reflections
3215 reflections with I > 2σ(I)
R_int = 0.043

Refinement

R[F² > 2σ(F²)] = 0.034
wR(F²) = 0.087
S = 1.05
3659 reflections
217 parameters
H-atom parameters constrained
Δρ_max = 0.54 e Å⁻³
Δρ_min = −0.48 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1C⋯Cl2ⁱ	0.88	2.74	3.241 (2)	117
N3—H3A⋯O1	0.88	2.12	2.870 (3)	143
Symmetry code: (i) x, y-1, z.

Data collection: SMART (Bruker, 2000 ); cell refinement: SMART; data reduction: SAINT (Bruker, 2000); 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 I, global. DOI: 10.1107/S1600536808027773/bt2778sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808027773/bt2778Isup2.hkl

checkCIF report

Comment top

Recently, the photophysical properties of coordination compounds of d₁₀ monovalent ions of the coinage metals have been of great interests. And metallomacrocyclic compounds are a rapidly growing field concerning due to their rich luminescent properties (Ren et al. 2004). Here, we present the syntheses and structural characterization of a dimeric [2:2] metallomacrocyclic compound [Zn₂(bib)₂Cl₂].2DMF (bib = 1,3-bis(4,5-Dihydro-1H-imidazol-2-yl)benzene).

The asymmetric unit of the title compound, [Zn₂(bib)₂Cl₂].2DMF, contains one Zn(II) cation, one bib ligand, two chloride ions and one DMF molecule. In the compound, the Zn(II) ion displays a tetrahedral geometry, being surrounded by two bib ligands and two chloride ions. Each bib acts as a bidentate ligand and every two bib ligands ligate a pair of Zn(II) ions resulting in a dimeric [2:2] metallomacrocyclic structure. Adjacent molecules are further linked by the N-H···Cl hyrogen bonds and the solvent is linked to the complex by N-H···O hydrogen bonds.

Related literature top

For related structures, see: Ren et al. (2004); (2007)

Experimental top

To a solution of ZnCl₂.2H₂O (0.172 g, 1 mmol) in CH₃OH (5 ml), an aqueous solution (5 ml) of bib (0.214 g, 1 mmol) was added. After the mixture was stirred for half an hour, white precipitate was filtrated, dried and collected. Then the white solids were completely dissolved into 2 ml DMF by heating. The DMF solution are placed into a glass test tube, and ether vapors were slowly diffused into the solution. After four weeks, colorless block crystals were obtained [yield 10% (8.5 mg) based on Zn(II)].

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SMART (Bruker, 2000); data reduction: SAINT (Bruker, 2000); 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 title compound with 30% thermal ellipsoids. Symmetry code: a: 1 - x, 1 - y, -z.
	Fig. 2. Partial packing diagram of the title compound. The H atoms bonded to C atoms are omitted for clarity.

Bis[µ-1,3-bis(4,5-dihydroimidazol-2-yl)benzene-κ²N:N']bis[dichloridozinc(II)] N,N'-dimethylformamide disolvate top

Crystal data top

[Zn₂Cl₄(C₁₂H₁₄N₄)₂]·2C₃H₇NO	F(000) = 872
M_r = 847.28	D_x = 1.495 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 781 reflections
a = 8.1774 (11) Å	θ = 2.4–28.0°
b = 8.5032 (12) Å	µ = 1.60 mm⁻¹
c = 27.097 (4) Å	T = 123 K
β = 92.890 (2)°	Block, colorless
V = 1881.8 (4) Å³	0.43 × 0.27 × 0.20 mm
Z = 2

Data collection top

Bruker APEX CCD diffractometer	3659 independent reflections
Radiation source: fine-focus sealed tube	3215 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.043
phi and ω scan	θ_max = 26.0°, θ_min = 2.8°
Absorption correction: multi-scan (SADABS; Sheldrick, 2000)	h = −10→9
T_min = 0.546, T_max = 0.740	k = −10→10
13375 measured reflections	l = −31→33

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)] = 0.034	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.087	H-atom parameters constrained
S = 1.05	w = 1/[σ²(F_o²) + (0.0445P)² + 0.1856P] where P = (F_o² + 2F_c²)/3
3659 reflections	(Δ/σ)_max = 0.001
217 parameters	Δρ_max = 0.54 e Å⁻³
0 restraints	Δρ_min = −0.48 e Å⁻³

Crystal data top

[Zn₂Cl₄(C₁₂H₁₄N₄)₂]·2C₃H₇NO	V = 1881.8 (4) Å³
M_r = 847.28	Z = 2
Monoclinic, P2₁/c	Mo Kα radiation
a = 8.1774 (11) Å	µ = 1.60 mm⁻¹
b = 8.5032 (12) Å	T = 123 K
c = 27.097 (4) Å	0.43 × 0.27 × 0.20 mm
β = 92.890 (2)°

Data collection top

Bruker APEX CCD diffractometer	3659 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2000)	3215 reflections with I > 2σ(I)
T_min = 0.546, T_max = 0.740	R_int = 0.043
13375 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.034	0 restraints
wR(F²) = 0.087	H-atom parameters constrained
S = 1.05	Δρ_max = 0.54 e Å⁻³
3659 reflections	Δρ_min = −0.48 e Å⁻³
217 parameters

Special details top

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 (Å²) top

	x	y	z	U_iso*/U_eq
Zn1	0.48008 (3)	0.59217 (3)	0.126447 (9)	0.01901 (11)
Cl1	0.75119 (7)	0.59787 (7)	0.12124 (2)	0.03078 (16)
Cl2	0.39514 (8)	0.76920 (7)	0.18274 (2)	0.03058 (17)
N1	0.3153 (3)	0.1342 (2)	0.15690 (7)	0.0258 (5)
H1C	0.2681	0.0467	0.1462	0.031*
N2	0.4140 (2)	0.3782 (2)	0.15104 (7)	0.0207 (4)
N3	0.8313 (2)	0.3109 (2)	−0.00124 (7)	0.0229 (4)
H3A	0.8515	0.2981	0.0307	0.028*
N4	0.6803 (2)	0.3684 (2)	−0.06974 (7)	0.0204 (4)
C1	0.3390 (4)	0.1829 (3)	0.20863 (9)	0.0317 (6)
H1A	0.4348	0.1300	0.2251	0.038*
H1B	0.2406	0.1617	0.2274	0.038*
C2	0.3685 (3)	0.3594 (3)	0.20290 (9)	0.0287 (6)
H2A	0.2681	0.4198	0.2091	0.034*
H2B	0.4581	0.3955	0.2261	0.034*
C3	0.3786 (3)	0.2473 (3)	0.12837 (8)	0.0196 (5)
C4	0.3941 (3)	0.2201 (3)	0.07490 (8)	0.0190 (5)
C5	0.2771 (3)	0.1283 (3)	0.04869 (9)	0.0211 (5)
H5A	0.1897	0.0817	0.0653	0.025*
C6	0.2896 (3)	0.1059 (3)	−0.00154 (9)	0.0221 (5)
H6A	0.2091	0.0454	−0.0195	0.026*
C7	0.4181 (3)	0.1707 (3)	−0.02578 (8)	0.0200 (5)
H7A	0.4255	0.1550	−0.0603	0.024*
C8	0.5371 (3)	0.2590 (2)	0.00036 (8)	0.0185 (5)
C9	0.5245 (3)	0.2843 (3)	0.05072 (8)	0.0190 (5)
H9A	0.6048	0.3453	0.0686	0.023*
C10	0.6822 (3)	0.3157 (3)	−0.02469 (8)	0.0188 (5)
C11	0.9542 (3)	0.3309 (3)	−0.03839 (8)	0.0248 (5)
H11A	0.9963	0.2285	−0.0496	0.030*
H11B	1.0469	0.3971	−0.0259	0.030*
C12	0.8515 (3)	0.4138 (3)	−0.07927 (9)	0.0256 (5)
H12A	0.8659	0.5292	−0.0772	0.031*
H12B	0.8819	0.3774	−0.1123	0.031*
N5	0.8751 (3)	0.1284 (3)	0.16839 (8)	0.0381 (6)
C13	0.8524 (5)	0.2201 (5)	0.21257 (12)	0.0666 (11)
H13A	0.8509	0.3322	0.2042	0.100*
H13B	0.9426	0.1990	0.2369	0.100*
H13C	0.7483	0.1911	0.2265	0.100*
C14	0.8795 (7)	−0.0394 (5)	0.17315 (14)	0.0913 (17)
H14A	0.8958	−0.0869	0.1408	0.137*
H14B	0.7758	−0.0766	0.1855	0.137*
H14C	0.9698	−0.0697	0.1963	0.137*
C15	0.8906 (3)	0.1948 (3)	0.12484 (10)	0.0328 (6)
H15A	0.8902	0.3064	0.1239	0.039*
O1	0.9055 (2)	0.1264 (2)	0.08571 (6)	0.0313 (4)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Zn1	0.02203 (17)	0.02012 (16)	0.01476 (16)	0.00103 (10)	−0.00025 (11)	0.00084 (10)
Cl1	0.0216 (3)	0.0318 (3)	0.0388 (4)	−0.0006 (2)	−0.0008 (3)	0.0019 (3)
Cl2	0.0501 (4)	0.0242 (3)	0.0176 (3)	0.0052 (3)	0.0033 (3)	−0.0022 (2)
N1	0.0358 (12)	0.0240 (10)	0.0179 (10)	−0.0066 (9)	0.0033 (9)	0.0009 (8)
N2	0.0265 (11)	0.0222 (10)	0.0135 (10)	0.0017 (8)	0.0020 (8)	0.0011 (7)
N3	0.0216 (11)	0.0327 (11)	0.0144 (10)	−0.0011 (9)	−0.0005 (8)	0.0020 (8)
N4	0.0194 (10)	0.0252 (10)	0.0167 (10)	0.0023 (8)	0.0026 (8)	0.0006 (8)
C1	0.0473 (17)	0.0289 (13)	0.0194 (13)	−0.0010 (12)	0.0065 (11)	0.0035 (10)
C2	0.0439 (16)	0.0279 (13)	0.0145 (12)	0.0012 (11)	0.0038 (11)	0.0021 (10)
C3	0.0179 (12)	0.0227 (11)	0.0180 (12)	0.0022 (9)	0.0003 (9)	0.0033 (9)
C4	0.0210 (12)	0.0178 (11)	0.0182 (12)	0.0022 (9)	0.0009 (9)	−0.0002 (9)
C5	0.0190 (12)	0.0204 (11)	0.0240 (13)	0.0017 (9)	0.0014 (10)	0.0028 (9)
C6	0.0215 (13)	0.0194 (11)	0.0245 (13)	0.0020 (9)	−0.0065 (10)	−0.0011 (9)
C7	0.0235 (13)	0.0201 (11)	0.0160 (11)	0.0045 (9)	−0.0021 (9)	0.0007 (9)
C8	0.0212 (12)	0.0184 (11)	0.0159 (11)	0.0028 (9)	−0.0006 (9)	0.0015 (9)
C9	0.0210 (12)	0.0186 (11)	0.0171 (12)	0.0018 (9)	−0.0010 (9)	−0.0009 (9)
C10	0.0233 (13)	0.0169 (10)	0.0161 (12)	0.0019 (9)	−0.0002 (9)	−0.0024 (9)
C11	0.0198 (12)	0.0338 (13)	0.0208 (12)	0.0004 (10)	0.0008 (10)	0.0015 (10)
C12	0.0217 (13)	0.0340 (14)	0.0211 (13)	0.0005 (10)	0.0017 (10)	0.0049 (10)
N5	0.0468 (15)	0.0488 (15)	0.0192 (12)	−0.0060 (11)	0.0050 (10)	−0.0011 (10)
C13	0.071 (3)	0.096 (3)	0.0334 (19)	0.009 (2)	0.0134 (17)	−0.0192 (18)
C14	0.184 (5)	0.052 (2)	0.038 (2)	−0.034 (3)	0.008 (3)	0.0071 (18)
C15	0.0330 (16)	0.0336 (14)	0.0318 (15)	0.0057 (12)	0.0013 (11)	0.0033 (12)
O1	0.0307 (10)	0.0468 (11)	0.0163 (9)	0.0015 (8)	−0.0001 (7)	0.0016 (8)

Geometric parameters (Å, º) top

Zn1—N4ⁱ	1.9978 (19)	C5—H5A	0.9500
Zn1—N2	2.0205 (19)	C6—C7	1.382 (3)
Zn1—Cl1	2.2291 (7)	C6—H6A	0.9500
Zn1—Cl2	2.2764 (7)	C7—C8	1.394 (3)
N1—C3	1.353 (3)	C7—H7A	0.9500
N1—C1	1.465 (3)	C8—C9	1.390 (3)
N1—H1C	0.8800	C8—C10	1.477 (3)
N2—C3	1.298 (3)	C9—H9A	0.9500
N2—C2	1.480 (3)	C11—C12	1.528 (3)
N3—C10	1.347 (3)	C11—H11A	0.9900
N3—C11	1.468 (3)	C11—H11B	0.9900
N3—H3A	0.8800	C12—H12A	0.9900
N4—C10	1.300 (3)	C12—H12B	0.9900
N4—C12	1.487 (3)	N5—C15	1.320 (3)
N4—Zn1ⁱ	1.9978 (19)	N5—C14	1.433 (4)
C1—C2	1.529 (3)	N5—C13	1.449 (4)
C1—H1A	0.9900	C13—H13A	0.9800
C1—H1B	0.9900	C13—H13B	0.9800
C2—H2A	0.9900	C13—H13C	0.9800
C2—H2B	0.9900	C14—H14A	0.9800
C3—C4	1.479 (3)	C14—H14B	0.9800
C4—C9	1.391 (3)	C14—H14C	0.9800
C4—C5	1.400 (3)	C15—O1	1.221 (3)
C5—C6	1.383 (3)	C15—H15A	0.9500

N4ⁱ—Zn1—N2	103.21 (8)	C6—C7—C8	120.1 (2)
N4ⁱ—Zn1—Cl1	124.35 (6)	C6—C7—H7A	120.0
N2—Zn1—Cl1	108.90 (6)	C8—C7—H7A	120.0
N4ⁱ—Zn1—Cl2	101.17 (6)	C9—C8—C7	119.9 (2)
N2—Zn1—Cl2	106.18 (6)	C9—C8—C10	120.1 (2)
Cl1—Zn1—Cl2	111.47 (3)	C7—C8—C10	119.9 (2)
C3—N1—C1	108.03 (19)	C8—C9—C4	119.9 (2)
C3—N1—H1C	126.0	C8—C9—H9A	120.1
C1—N1—H1C	126.0	C4—C9—H9A	120.1
C3—N2—C2	107.20 (19)	N4—C10—N3	114.9 (2)
C3—N2—Zn1	132.35 (16)	N4—C10—C8	124.9 (2)
C2—N2—Zn1	119.66 (14)	N3—C10—C8	120.2 (2)
C10—N3—C11	107.93 (18)	N3—C11—C12	100.39 (18)
C10—N3—H3A	126.0	N3—C11—H11A	111.7
C11—N3—H3A	126.0	C12—C11—H11A	111.7
C10—N4—C12	106.62 (19)	N3—C11—H11B	111.7
C10—N4—Zn1ⁱ	139.15 (17)	C12—C11—H11B	111.7
C12—N4—Zn1ⁱ	114.22 (14)	H11A—C11—H11B	109.5
N1—C1—C2	101.20 (19)	N4—C12—C11	104.02 (19)
N1—C1—H1A	111.5	N4—C12—H12A	111.0
C2—C1—H1A	111.5	C11—C12—H12A	111.0
N1—C1—H1B	111.5	N4—C12—H12B	111.0
C2—C1—H1B	111.5	C11—C12—H12B	111.0
H1A—C1—H1B	109.3	H12A—C12—H12B	109.0
N2—C2—C1	104.55 (19)	C15—N5—C14	120.2 (3)
N2—C2—H2A	110.8	C15—N5—C13	122.1 (3)
C1—C2—H2A	110.8	C14—N5—C13	117.7 (3)
N2—C2—H2B	110.8	N5—C13—H13A	109.5
C1—C2—H2B	110.8	N5—C13—H13B	109.5
H2A—C2—H2B	108.9	H13A—C13—H13B	109.5
N2—C3—N1	115.0 (2)	N5—C13—H13C	109.5
N2—C3—C4	124.7 (2)	H13A—C13—H13C	109.5
N1—C3—C4	120.2 (2)	H13B—C13—H13C	109.5
C9—C4—C5	120.0 (2)	N5—C14—H14A	109.5
C9—C4—C3	120.4 (2)	N5—C14—H14B	109.5
C5—C4—C3	119.6 (2)	H14A—C14—H14B	109.5
C6—C5—C4	119.6 (2)	N5—C14—H14C	109.5
C6—C5—H5A	120.2	H14A—C14—H14C	109.5
C4—C5—H5A	120.2	H14B—C14—H14C	109.5
C7—C6—C5	120.5 (2)	O1—C15—N5	126.3 (3)
C7—C6—H6A	119.7	O1—C15—H15A	116.9
C5—C6—H6A	119.7	N5—C15—H15A	116.9

Symmetry code: (i) −x+1, −y+1, −z.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1C···Cl2ⁱⁱ	0.88	2.74	3.241 (2)	117
N3—H3A···O1	0.88	2.12	2.870 (3)	143

Symmetry code: (ii) x, y−1, z.

Experimental details

Crystal data
Chemical formula	[Zn₂Cl₄(C₁₂H₁₄N₄)₂]·2C₃H₇NO
M_r	847.28
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	123
a, b, c (Å)	8.1774 (11), 8.5032 (12), 27.097 (4)
β (°)	92.890 (2)
V (Å³)	1881.8 (4)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	1.60
Crystal size (mm)	0.43 × 0.27 × 0.20

Data collection
Diffractometer	Bruker APEX CCD diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 2000)
T_min, T_max	0.546, 0.740
No. of measured, independent and observed [I > 2σ(I)] reflections	13375, 3659, 3215
R_int	0.043
(sin θ/λ)_max (Å⁻¹)	0.617

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.034, 0.087, 1.05
No. of reflections	3659
No. of parameters	217
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.54, −0.48

Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), 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
N1—H1C···Cl2ⁱ	0.88	2.74	3.241 (2)	117.2
N3—H3A···O1	0.88	2.12	2.870 (3)	143.2

Symmetry code: (i) x, y−1, z.

Acknowledgements

The authors thank the Program for Young Excellent Talents in Southeast University for financial support.

References

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