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Acta Cryst. (2008). E64, m1408-m1409    [ doi:10.1107/S1600536808032704 ]

Di-[mu]-chlorido-dichlorido-bis{[mu]-6,6'-dimethoxy-2,2'-[o-phenylenebis(nitrilomethylidyne)]diphenolato}dilead(II)dizinc(II) N,N'-dimethylformamide disolvate

H. Wang, D. Zhang and L.-F. Zhang

Abstract top

The title compound, [Pb2Zn2(C22H18N2O4)2Cl4]·2C3H7NO, was synthesized using a step-by-step method and has a slipped sandwich configuration. The coordination environment of the Zn2+ ion is distorted square-pyramidal and it is coordinated by N2O2 of the Schiff base ligand and chloride; each Pb2+ ion is coordinated by the four 6,6'-dimethoxy-2,2'-[o-phenylenebis(nitrilomethylidyne)]diphenolate (L) O atoms and two chloride ions. The ZnIIPbII dinuclear unit, through an inversion-symmetry operation, forms a tetrameric complex with double chloride bridges.

Comment top

Heterometallic complexes have been intensively studied owing to their unique physical and chemical properties (Ward et al., 2007 and Ni et al., 2005). In addition, these compounds exist at the active sites of many metalloenzymes and play important roles in biological systems (Karlin, 1993). It is necessary to extend the application of heterometallic compounds. Herein, a novel heterometallic tetranuclear (ZnIIPbII)2 compound has been obtained using step-by-step method and its structure is depcited.

The compound I is a tetranuclear neutral complex with a slipped sandwich configuration (Fig. 1). Each Zn(II) is coordinated in a square-pyramidal geometry with the basal square formed by two nitrogen atoms and two oxygen atoms from L ligand, with the apical position occupied by terminal chlorine atom. The coordination environment of each Pb(II) is a distorted octahedral geometry composed of four oxygen atoms from ligand and two bridging chlorine atoms. Zn(II) and Pb(II) are connected via two bridging oxygen atoms of the ligand, and two Pb(II) atoms are connected by two bridging chlorine atoms. The bond lengths of Zn—O, Zn—N and Zn—Cl are normal (Korupoju et al., 2000). Through π-π interaction between the rings C9—C14 and C16—C21 [symmetry code; (i) -1 + x, y, z] with centroid distance of 3.730 (3) /A [Cg1··· Cg2i ] the discrete tetranuclear (ZnIIPbII)2 units forms a supramolecular structure (Fig. 2).

Related literature top

For related literature, see: Karlin (1993); Korupoju et al. (2000); Lo et al. (2004); Ni et al. (2005); Sui et al. (2007); Ward (2007).

Experimental top

The H2L ligand and complex ZnL was synthesized according to the literature (Lo et al., 2004; Sui et al. 2007). Synthesis of the compound I was obtained by allowing the mixure of ZnL (0.088 g, 0.2 mmol) and PbCl2.2H2O(0.063 g, 0.2 mmol) to be refluxed in the DMF solution, cooled down to room temperature, then filtered, and suitable yellow crystals were obtained by slow evaporation of the filtrate at room temperature (yield: about 45%).

Refinement top

All H-atoms bound to carbon were refined using a riding model with distance C—H = 0.93 Å, Uiso = 1.2Ueq (C) for aromatic atoms and C—H = 0.96 Å, Uiso = 1.5Ueq (C) for methyl atoms.

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT-Plus (Bruker, 2001); data reduction: SAINT-Plus (Bruker, 2001); program(s) used to solve structure: SHELXL97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: XP in SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. A view of (I) with the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level, solvate DMF molecules are ommited for clarity.
[Figure 2] Fig. 2. A view of crystal packing based on π–π interactions.
Di-µ-chlorido-dichlorido-bis{µ-6,6'-dimethoxy-2,2'-[o- phenylenebis(nitrilomethylidyne)]diphenolato}dilead(II)dizinc(II) N,N'-dimethylformamide disolvate top
Crystal data top
[Zn2Pb2(C22H18N2O4)2Cl4]·2C3H7NOF(000) = 1528
Mr = 1581.88Dx = 1.952 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3748 reflections
a = 7.4955 (6) Åθ = 1.9–26.5°
b = 32.119 (3) ŵ = 7.38 mm−1
c = 11.2366 (9) ÅT = 295 K
β = 95.729 (2)°Block, yellow
V = 2691.7 (4) Å30.20 × 0.15 × 0.10 mm
Z = 2
Data collection top
Bruker APEXII CCD area-detector
diffractometer		4719 independent reflections
Radiation source: fine-focus sealed tube3176 reflections with I > 2σ(I)
graphiteRint = 0.063
Detector resolution: 0 pixels mm-1θmax = 25.0°, θmin = 1.9°
φ and ω scansh = −8→7
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)		k = −38→37
Tmin = 0.320, Tmax = 0.526l = −13→12
13373 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.038Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.066H-atom parameters constrained
S = 0.93 w = 1/[σ2(Fo2) + (0.017P)2]
where P = (Fo2 + 2Fc2)/3
4719 reflections(Δ/σ)max = 0.001
336 parametersΔρmax = 0.55 e Å−3
0 restraintsΔρmin = −0.64 e Å−3
Crystal data top
[Zn2Pb2(C22H18N2O4)2Cl4]·2C3H7NOV = 2691.7 (4) Å3
Mr = 1581.88Z = 2
Monoclinic, P21/cMo Kα radiation
a = 7.4955 (6) ŵ = 7.38 mm−1
b = 32.119 (3) ÅT = 295 K
c = 11.2366 (9) Å0.20 × 0.15 × 0.10 mm
β = 95.729 (2)°
Data collection top
Bruker APEXII CCD area-detector
diffractometer		4719 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)		3176 reflections with I > 2σ(I)
Tmin = 0.320, Tmax = 0.526Rint = 0.063
13373 measured reflectionsθmax = 25.0°
Refinement top
R[F2 > 2σ(F2)] = 0.038H-atom parameters constrained
wR(F2) = 0.066Δρmax = 0.55 e Å−3
S = 0.93Δρmin = −0.64 e Å−3
4719 reflectionsAbsolute structure: ?
336 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
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
xyzUiso*/Ueq
C11.1566 (10)−0.0054 (2)0.1667 (6)0.067 (2)
H1A1.0503−0.01770.19260.100*
H1B1.2482−0.02630.16550.100*
H1C1.13000.00590.08790.100*
C21.3705 (10)0.0487 (2)0.2264 (6)0.0448 (19)
C31.4939 (10)0.0359 (2)0.1533 (6)0.054 (2)
H31.47540.01090.11180.065*
C41.6467 (10)0.0591 (2)0.1391 (6)0.057 (2)
H41.72870.05000.08780.068*
C51.6746 (9)0.0953 (2)0.2017 (6)0.0458 (19)
H51.77780.11060.19320.055*
C61.5510 (8)0.11026 (19)0.2791 (5)0.0309 (16)
C71.3931 (9)0.0871 (2)0.2908 (5)0.0339 (16)
C81.5982 (8)0.14809 (19)0.3455 (6)0.0349 (17)
H81.71410.15820.34330.042*
C91.5514 (8)0.20447 (19)0.4732 (5)0.0308 (16)
C101.7104 (8)0.22575 (19)0.4619 (6)0.0350 (17)
H101.78750.21670.40730.042*
C111.7534 (10)0.2602 (2)0.5317 (6)0.048 (2)
H111.86070.27400.52440.058*
C121.6408 (10)0.2745 (2)0.6123 (6)0.052 (2)
H121.67220.29780.65890.062*
C131.4798 (9)0.2540 (2)0.6236 (6)0.0427 (19)
H131.40190.26410.67630.051*
C141.4350 (8)0.21857 (19)0.5565 (5)0.0303 (16)
C151.1756 (9)0.1993 (2)0.6481 (6)0.0408 (18)
H151.20670.22020.70360.049*
C161.0212 (9)0.1750 (2)0.6657 (6)0.0363 (17)
C170.9185 (10)0.1873 (2)0.7569 (6)0.057 (2)
H170.95370.21070.80200.069*
C180.7699 (11)0.1665 (3)0.7822 (7)0.073 (3)
H180.70500.17570.84340.088*
C190.7150 (10)0.1318 (2)0.7177 (7)0.059 (2)
H190.61370.11730.73600.071*
C200.8083 (9)0.1183 (2)0.6266 (6)0.0422 (18)
C210.9628 (8)0.13985 (19)0.5965 (6)0.0322 (16)
C220.5984 (9)0.0631 (2)0.5684 (6)0.059 (2)
H22A0.58490.04000.51420.088*
H22B0.50060.08210.55100.088*
H22C0.59870.05320.64910.088*
C231.2723 (12)0.0874 (3)0.8580 (7)0.087 (3)
H23A1.39620.07980.87450.130*
H23B1.25430.10100.78170.130*
H23C1.19940.06280.85680.130*
C241.3274 (12)0.1533 (3)0.9737 (8)0.092 (3)
H24A1.45160.14590.98910.138*
H24B1.28990.16781.04170.138*
H24C1.31130.17100.90460.138*
C251.0834 (13)0.1067 (3)1.0144 (8)0.082 (3)
H251.05380.12531.07290.099*
N11.4929 (7)0.16881 (15)0.4072 (4)0.0302 (12)
N21.2753 (7)0.19497 (15)0.5626 (4)0.0341 (13)
N31.2211 (9)0.1160 (2)0.9524 (6)0.069 (2)
O11.2183 (7)0.02728 (14)0.2479 (4)0.0568 (14)
O21.2672 (5)0.09841 (12)0.3583 (4)0.0358 (11)
O31.0450 (6)0.12607 (12)0.5055 (4)0.0411 (12)
O40.7656 (6)0.08411 (14)0.5550 (4)0.0484 (13)
O50.9982 (10)0.0763 (2)0.9986 (7)0.126 (3)
Zn11.22386 (10)0.15710 (2)0.41482 (7)0.0330 (2)
Pb11.00874 (4)0.060131 (8)0.40830 (2)0.04083 (10)
Cl11.0695 (2)0.19248 (6)0.26480 (16)0.0515 (5)
Cl21.1909 (2)0.02574 (6)0.59314 (17)0.0555 (5)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.079 (6)0.048 (5)0.072 (6)−0.013 (4)−0.002 (5)−0.025 (5)
C20.053 (5)0.046 (5)0.037 (4)0.000 (4)0.012 (4)−0.010 (4)
C30.062 (6)0.042 (5)0.059 (5)−0.006 (4)0.016 (5)−0.025 (4)
C40.057 (5)0.058 (5)0.058 (5)0.003 (4)0.024 (4)−0.027 (5)
C50.034 (4)0.061 (5)0.043 (5)0.006 (4)0.008 (4)−0.001 (4)
C60.034 (4)0.029 (4)0.032 (4)0.005 (3)0.011 (3)0.002 (3)
C70.038 (4)0.033 (4)0.029 (4)0.008 (3)0.000 (3)0.005 (3)
C80.027 (4)0.032 (4)0.046 (4)−0.006 (3)0.006 (4)0.007 (3)
C90.025 (4)0.037 (4)0.031 (4)0.003 (3)0.000 (3)0.002 (3)
C100.029 (4)0.039 (4)0.036 (4)−0.004 (3)0.002 (3)−0.002 (3)
C110.045 (5)0.043 (5)0.054 (5)−0.016 (4)−0.004 (4)−0.002 (4)
C120.051 (5)0.051 (5)0.054 (5)−0.007 (4)0.012 (4)−0.014 (4)
C130.042 (5)0.038 (4)0.049 (5)0.002 (3)0.009 (4)0.000 (4)
C140.030 (4)0.030 (4)0.030 (4)−0.002 (3)−0.004 (3)0.003 (3)
C150.046 (5)0.038 (4)0.040 (4)−0.006 (3)0.012 (4)0.003 (3)
C160.043 (4)0.035 (4)0.033 (4)−0.001 (3)0.016 (4)0.002 (3)
C170.057 (5)0.053 (5)0.065 (6)−0.007 (4)0.025 (5)−0.018 (4)
C180.076 (6)0.073 (7)0.081 (7)−0.017 (5)0.056 (5)−0.017 (5)
C190.047 (5)0.063 (6)0.073 (6)−0.014 (4)0.031 (5)−0.007 (5)
C200.035 (4)0.046 (5)0.046 (5)−0.004 (3)0.009 (4)0.003 (4)
C210.026 (4)0.034 (4)0.038 (4)0.005 (3)0.011 (3)−0.004 (3)
C220.050 (5)0.063 (5)0.063 (5)−0.020 (4)0.010 (4)0.012 (4)
C230.084 (7)0.093 (7)0.088 (7)−0.016 (6)0.037 (6)−0.029 (6)
C240.101 (8)0.070 (7)0.101 (8)−0.049 (6)−0.007 (6)−0.013 (6)
C250.089 (8)0.074 (7)0.090 (7)−0.029 (6)0.043 (6)−0.018 (6)
N10.029 (3)0.029 (3)0.033 (3)0.000 (3)0.007 (3)−0.001 (3)
N20.032 (3)0.034 (3)0.038 (3)−0.006 (2)0.011 (3)−0.001 (3)
N30.067 (5)0.073 (5)0.068 (5)−0.018 (4)0.017 (4)−0.010 (4)
O10.069 (4)0.044 (3)0.060 (3)−0.015 (3)0.018 (3)−0.023 (3)
O20.034 (3)0.030 (3)0.045 (3)−0.002 (2)0.013 (2)−0.005 (2)
O30.043 (3)0.033 (3)0.051 (3)−0.003 (2)0.023 (2)−0.003 (2)
O40.035 (3)0.046 (3)0.065 (3)−0.012 (2)0.013 (3)−0.004 (3)
O50.115 (6)0.114 (7)0.158 (7)−0.039 (5)0.063 (5)−0.014 (5)
Zn10.0303 (4)0.0303 (4)0.0393 (5)−0.0020 (3)0.0080 (4)−0.0011 (4)
Pb10.03765 (16)0.03548 (16)0.05010 (18)−0.00722 (14)0.00808 (13)−0.00237 (15)
Cl10.0443 (11)0.0581 (13)0.0522 (12)0.0087 (9)0.0043 (10)0.0121 (10)
Cl20.0504 (12)0.0521 (12)0.0621 (13)−0.0162 (9)−0.0032 (10)0.0058 (10)
Geometric parameters (Å, °) top
C1—O11.437 (7)C17—C181.354 (10)
C1—H1A0.9600C17—H170.9300
C1—H1B0.9600C18—C191.370 (9)
C1—H1C0.9600C18—H180.9300
C2—C31.361 (9)C19—C201.367 (9)
C2—O11.373 (8)C19—H190.9300
C2—C71.432 (8)C20—O41.379 (7)
C3—C41.389 (9)C20—C211.420 (8)
C3—H30.9300C21—O31.321 (7)
C4—C51.365 (9)C22—O41.444 (7)
C4—H40.9300C22—H22A0.9600
C5—C61.416 (8)C22—H22B0.9600
C5—H50.9300C22—H22C0.9600
C6—C71.415 (8)C23—N31.483 (9)
C6—C81.451 (8)C23—H23A0.9600
C7—O21.319 (7)C23—H23B0.9600
C8—N11.286 (7)C23—H23C0.9600
C8—H80.9300C24—N31.446 (9)
C9—C101.391 (8)C24—H24A0.9600
C9—N11.411 (7)C24—H24B0.9600
C9—C141.416 (8)C24—H24C0.9600
C10—C111.375 (8)C25—O51.172 (9)
C10—H100.9300C25—N31.335 (10)
C11—C121.377 (9)C25—H250.9300
C11—H110.9300N1—Zn12.062 (5)
C12—C131.392 (9)N2—Zn12.064 (5)
C12—H120.9300O1—Pb12.720 (5)
C13—C141.389 (8)O2—Zn12.026 (4)
C13—H130.9300O2—Pb12.408 (4)
C14—N21.424 (7)O3—Zn12.025 (4)
C15—N21.283 (7)O3—Pb12.386 (4)
C15—C161.426 (8)O4—Pb12.690 (5)
C15—H150.9300Zn1—Cl12.2544 (18)
C16—C171.399 (9)Pb1—Cl22.6138 (18)
C16—C211.416 (8)
O1—C1—H1A109.5O3—C21—C20118.4 (6)
O1—C1—H1B109.5C16—C21—C20118.2 (6)
H1A—C1—H1B109.5O4—C22—H22A109.5
O1—C1—H1C109.5O4—C22—H22B109.5
H1A—C1—H1C109.5H22A—C22—H22B109.5
H1B—C1—H1C109.5O4—C22—H22C109.5
C3—C2—O1125.5 (7)H22A—C22—H22C109.5
C3—C2—C7120.8 (7)H22B—C22—H22C109.5
O1—C2—C7113.7 (6)N3—C23—H23A109.5
C2—C3—C4121.7 (7)N3—C23—H23B109.5
C2—C3—H3119.2H23A—C23—H23B109.5
C4—C3—H3119.2N3—C23—H23C109.5
C5—C4—C3118.9 (7)H23A—C23—H23C109.5
C5—C4—H4120.5H23B—C23—H23C109.5
C3—C4—H4120.5N3—C24—H24A109.5
C4—C5—C6122.0 (7)N3—C24—H24B109.5
C4—C5—H5119.0H24A—C24—H24B109.5
C6—C5—H5119.0N3—C24—H24C109.5
C7—C6—C5118.9 (6)H24A—C24—H24C109.5
C7—C6—C8123.7 (6)H24B—C24—H24C109.5
C5—C6—C8117.3 (6)O5—C25—N3123.1 (10)
O2—C7—C6124.2 (6)O5—C25—H25118.5
O2—C7—C2118.2 (6)N3—C25—H25118.5
C6—C7—C2117.6 (6)C8—N1—C9121.9 (5)
N1—C8—C6125.4 (6)C8—N1—Zn1125.7 (4)
N1—C8—H8117.3C9—N1—Zn1112.3 (4)
C6—C8—H8117.3C15—N2—C14122.3 (6)
C10—C9—N1125.1 (6)C15—N2—Zn1126.2 (5)
C10—C9—C14119.6 (6)C14—N2—Zn1111.4 (4)
N1—C9—C14115.3 (5)C25—N3—C24122.8 (8)
C11—C10—C9119.8 (6)C25—N3—C23120.2 (7)
C11—C10—H10120.1C24—N3—C23117.1 (7)
C9—C10—H10120.1C2—O1—C1118.4 (5)
C10—C11—C12121.3 (7)C2—O1—Pb1117.8 (4)
C10—C11—H11119.3C1—O1—Pb1122.2 (4)
C12—C11—H11119.3C7—O2—Zn1125.6 (4)
C11—C12—C13119.7 (7)C7—O2—Pb1129.2 (4)
C11—C12—H12120.1Zn1—O2—Pb1104.13 (17)
C13—C12—H12120.1C21—O3—Zn1127.4 (4)
C14—C13—C12120.2 (7)C21—O3—Pb1127.7 (4)
C14—C13—H13119.9Zn1—O3—Pb1104.90 (17)
C12—C13—H13119.9C20—O4—C22117.7 (5)
C13—C14—C9119.3 (6)C20—O4—Pb1117.0 (4)
C13—C14—N2124.7 (6)C22—O4—Pb1125.3 (4)
C9—C14—N2116.0 (5)O3—Zn1—O280.49 (16)
N2—C15—C16125.8 (6)O3—Zn1—N1144.11 (18)
N2—C15—H15117.1O2—Zn1—N188.19 (18)
C16—C15—H15117.1O3—Zn1—N288.00 (18)
C17—C16—C21117.8 (6)O2—Zn1—N2141.06 (18)
C17—C16—C15117.4 (6)N1—Zn1—N279.7 (2)
C21—C16—C15124.8 (6)O3—Zn1—Cl1107.95 (13)
C18—C17—C16122.6 (7)O2—Zn1—Cl1108.74 (13)
C18—C17—H17118.7N1—Zn1—Cl1107.94 (14)
C16—C17—H17118.7N2—Zn1—Cl1110.20 (15)
C17—C18—C19120.1 (7)O3—Pb1—O266.18 (14)
C17—C18—H18120.0O3—Pb1—Cl289.13 (11)
C19—C18—H18120.0O2—Pb1—Cl291.86 (10)
C20—C19—C18120.3 (7)O3—Pb1—O461.20 (14)
C20—C19—H19119.8O2—Pb1—O4127.37 (14)
C18—C19—H19119.8Cl2—Pb1—O488.05 (11)
C19—C20—O4125.7 (7)O3—Pb1—O1126.94 (14)
C19—C20—C21121.0 (7)O2—Pb1—O160.79 (14)
O4—C20—C21113.4 (6)Cl2—Pb1—O194.14 (12)
O3—C21—C16123.4 (6)O4—Pb1—O1171.53 (14)
Table 1
Selected geometric parameters (Å, °) top
N1—Zn12.062 (5)O3—Zn12.025 (4)
N2—Zn12.064 (5)O3—Pb12.386 (4)
O1—Pb12.720 (5)O4—Pb12.690 (5)
O2—Zn12.026 (4)Zn1—Cl12.2544 (18)
O2—Pb12.408 (4)Pb1—Cl22.6138 (18)
O3—Zn1—O280.49 (16)O3—Pb1—O266.18 (14)
O3—Zn1—N1144.11 (18)O3—Pb1—Cl289.13 (11)
O2—Zn1—N188.19 (18)O2—Pb1—Cl291.86 (10)
O3—Zn1—N288.00 (18)O3—Pb1—O461.20 (14)
O2—Zn1—N2141.06 (18)O2—Pb1—O4127.37 (14)
N1—Zn1—N279.7 (2)Cl2—Pb1—O488.05 (11)
O3—Zn1—Cl1107.95 (13)O3—Pb1—O1126.94 (14)
O2—Zn1—Cl1108.74 (13)O2—Pb1—O160.79 (14)
N1—Zn1—Cl1107.94 (14)Cl2—Pb1—O194.14 (12)
N2—Zn1—Cl1110.20 (15)O4—Pb1—O1171.53 (14)
Acknowledgements top

This work was supported by the Natural Science Foundation of China and the Post-Doctoral Innovation Project of Shandong Province.

references
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