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Acta Cryst. (2008). E64, m692-m693    [ doi:10.1107/S160053680801057X ]

Dichloridobis(5-m-tolyl-1,3,4-thiadiazol-2-ylamine-[kappa]N3)zinc(II)

B. Wang, R. Wan, L.-H. Yin, F. Han and J.-T. Wang

Abstract top

In the molecule of the title compound, [ZnCl2(C9H9N3S)2], the ZnII atom is four-coordinated by two N atoms from two 5-m-tolyl-1,3,4-thiadiazol-2-ylamine ligands and two Cl anions in a distorted tetrahedral geometry. Intramolecular N-H...N, N-H...Cl and C-H...S hydrogen bonds result in the formation of one planar and one non-planar five-membered, one non-planar six-membered and one non-planar seven-membered ring. The six- and seven-membered rings have twist conformations, while the non-planar five-membered ring adopts an envelope conformation with the S atom displaced by 0.541 (3) Å from the plane of the other ring atoms. The planar five-membered ring is oriented at dihedral angles of 1.74 (3) and 1.08 (3)°, respectively, with respect to the adjacent aromatic and thiadiazole rings. In the crystal structure, intermolecular N-H...Cl hydrogen bonds link the molecules into a three-dimensional network.

Comment top

As a series of superior ligands, thiadiazoles and their derivatives can coordinate to many metal ions with nitrogen or sulfur atoms of the five-membered ring. In particular N,N'-linkage ligands, such as 1,3,4-thiadiazoles, are very versatile compounds that are able to bridge a wide range of inter-metallic separations through two close adjacent N donors (Alzuet et al., 2003). These complexes have received considerable attention in the past few years, due to their certain antibacterial and antifungal activities (Shen et al., 2004).

In the molecule of (I), (Fig. 1), ZnII atom is four-coordinated by two N atoms from two 5-m-tolyl-[1,3,4]thiadiazol-2-ylamine ligands and two Cl anions. It has a distorted tetrahedral coordination geometry (Table 1). Rings A (C2-C7), B (N1/N2/S1/C8/C9), C (N4/N5/S2/C17/C18) and D (C11-C16) are, of course, planar. The dihedral angles between them are A/B = 1.87 (3)°, A/C = 14.55 (3)°, A/D = 27.98 (4)°, B/C = 14.63 (4)°, B/D = 28.43 (3)° and C/D = 14.21 (3)°. The intramolecular N-H···N, N-H···Cl and C-H···S hydrogen bonds (Table 2) result in the formation of one planar F (S1/C4/C5/H5A/C8) and one non-planar G (S2/C15-C17/H16A) five-membered, one non-planar H (Zn/Cl1/N5/N6/H6B/C18) six-membered and one non-planar E (Zn/N2-N5/H3B/C9) seven-membered rings. Ring F is oriented with respect to the adjacent rings A and B at dihedral angles of A/F = 1.74 (3)° and B/F = 1.08 (3)°. So, rings A, B and F are nearly coplanar. Rings E and H have twisted conformations, having total puckering amplitudes, QT, of 0.712 (3) and 0.424 (2) Å, respectively (Cremer & Pople, 1975). Ring G adopts envelope conformation with sulfur atom displaced by -0.541 (3) Å from the plane of the other ring atoms.

In the crystal structure, intermolecular N-H···Cl hydrogen bonds (Table 2) link the molecules to form a three-dimensional network (Fig. 2), in which they may be effective in the stabilization of the structure.

Related literature top

For general background, see: Alzuet et al. (2003); Shen et al. (2004). For ring puckering parameters, see: Cremer & Pople (1975).

Experimental top

For the preparation of the title compound, the solution of ZnCl2 (0.5 mmol) in ethanol (20 ml) was added slowly to a solution of 5-m-tolyl-[1,3,4]- thiadiazol-2-ylamine (1.0 mmol) in ethanol (20 ml), and then heated under reflux for 2 h. The reaction mixture was left to cool to room temperature, and then filtered. The solid was recrystallized from ethanol to give the title compound, (I), (m.p. 453 K). Crystals of (I) suitable for X-ray analysis were obtained by slow evaporation of an acetone solution.

Refinement top

H atoms were positioned geometrically, with N-H = 0.86 Å (for NH2) and C-H = 0.93 and 0.96 Å for aromatic and methyl H, respectively, and constrained to ride on their parent atoms with Uiso(H) = xUeq(C,N), where x = 1.5 for methyl H, and x = 1.2 for all other H atoms.

Computing details top

Data collection: CAD-4 Software (Enraf–Nonius, 1989); cell refinement: CAD-4 Software (Enraf–Nonius, 1989); data reduction: XCAD4 (Harms & Wocadlo, 1995); 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
[Figure 1] Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. Hydrogen bonds are shown as dashed lines.
[Figure 2] Fig. 2. A partial packing diagram of (I). Hydrogen bonds are shown as dashed lines.
Dichloridobis(5-m-tolyl-1,3,4-thiadiazol-2-ylamine-κN3)zinc(II) top
Crystal data top
[ZnCl2(C9H9N3S)2]F000 = 1056
Mr = 518.77Dx = 1.584 Mg m−3
Monoclinic, P21/cMelting point: 453 K
Hall symbol: -P 2ybcMo Kα radiation
λ = 0.71073 Å
a = 10.826 (2) ÅCell parameters from 25 reflections
b = 11.233 (2) Åθ = 10–13º
c = 17.892 (4) ŵ = 1.58 mm−1
β = 90.10 (3)ºT = 298 (2) K
V = 2175.8 (7) Å3Block, yellow
Z = 40.20 × 0.10 × 0.10 mm
Data collection top
Enraf–Nonius CAD-4
diffractometer		Rint = 0.0000
Radiation source: fine-focus sealed tubeθmax = 25.2º
Monochromator: graphiteθmin = 1.9º
T = 298(2) Kh = −12→12
ω/2θ scansk = 0→13
Absorption correction: ψ scan
(North et al., 1968)		l = 0→21
Tmin = 0.742, Tmax = 0.8583 standard reflections
3917 measured reflections every 120 min
3917 independent reflections intensity decay: none
2310 reflections with I > 2σ(I)
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.086H-atom parameters constrained
wR(F2) = 0.211  w = 1/[σ2(Fo2) + (0.05P)2 + 19P]
where P = (Fo2 + 2Fc2)/3
S = 1.02(Δ/σ)max < 0.001
3917 reflectionsΔρmax = 0.62 e Å−3
256 parametersΔρmin = −0.97 e Å−3
Primary atom site location: structure-invariant direct methodsExtinction correction: none
Crystal data top
[ZnCl2(C9H9N3S)2]V = 2175.8 (7) Å3
Mr = 518.77Z = 4
Monoclinic, P21/cMo Kα
a = 10.826 (2) ŵ = 1.58 mm−1
b = 11.233 (2) ÅT = 298 (2) K
c = 17.892 (4) Å0.20 × 0.10 × 0.10 mm
β = 90.10 (3)º
Data collection top
Enraf–Nonius CAD-4
diffractometer		2310 reflections with I > 2σ(I)
Absorption correction: ψ scan
(North et al., 1968)		Rint = 0.0000
Tmin = 0.742, Tmax = 0.8583 standard reflections
3917 measured reflections every 120 min
3917 independent reflections intensity decay: none
Refinement top
R[F2 > 2σ(F2)] = 0.086? restraints
wR(F2) = 0.211H-atom parameters constrained
S = 1.02  w = 1/[σ2(Fo2) + (0.05P)2 + 19P]
where P = (Fo2 + 2Fc2)/3
3917 reflectionsΔρmax = 0.62 e Å−3
256 parametersΔρmin = −0.97 e Å−3
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 > 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
xyzUiso*/Ueq
Zn0.06433 (12)0.26059 (8)0.14033 (6)0.0679 (4)
Cl10.1115 (3)0.1322 (2)0.05026 (15)0.0820 (8)
Cl20.1997 (3)0.26430 (19)0.23734 (15)0.0794 (8)
S10.0144 (3)0.65934 (18)0.09796 (14)0.0734 (8)
S2−0.2594 (3)0.06983 (19)0.25635 (15)0.0797 (9)
N10.1364 (8)0.4722 (6)0.0595 (4)0.065 (2)
N20.0424 (7)0.4353 (6)0.1087 (4)0.065 (2)
N3−0.1161 (10)0.5103 (6)0.1810 (5)0.083 (3)
H3B−0.13210.44100.19900.099*
H3C−0.15880.57100.19480.099*
N4−0.1619 (7)0.2723 (6)0.2312 (4)0.0616 (19)
N5−0.0944 (7)0.1933 (6)0.1914 (4)0.0612 (19)
N6−0.0809 (9)−0.0115 (6)0.1629 (5)0.088 (3)
H6B−0.01870.00090.13410.106*
H6C−0.1088−0.08260.16880.106*
C10.4997 (13)0.5883 (12)−0.1215 (8)0.114 (5)
H1B0.49350.5048−0.11070.171*
H1C0.57900.6171−0.10580.171*
H1D0.49030.6007−0.17430.171*
C20.4016 (12)0.6533 (9)−0.0812 (6)0.082 (3)
C30.3158 (11)0.5948 (9)−0.0373 (6)0.080 (3)
H3A0.32260.5125−0.03350.096*
C40.2196 (12)0.6500 (8)0.0019 (5)0.077 (3)
C50.2031 (9)0.7744 (8)−0.0049 (6)0.068 (3)
H5A0.13900.81410.01910.081*
C60.2915 (11)0.8363 (10)−0.0513 (7)0.085 (3)
H6A0.28460.9181−0.05790.102*
C70.3826 (13)0.7774 (10)−0.0845 (7)0.086 (3)
H7A0.43860.8218−0.11230.104*
C80.1285 (11)0.5868 (7)0.0515 (5)0.071 (3)
C9−0.0319 (12)0.5226 (7)0.1353 (6)0.068 (3)
C10−0.6334 (10)0.2481 (11)0.4112 (7)0.092
H10A−0.67450.29950.44610.138*
H10B−0.61500.17350.43500.138*
H10C−0.68610.23440.36890.138*
C11−0.5168 (9)0.3049 (9)0.3860 (6)0.069 (2)
C12−0.4872 (10)0.4201 (9)0.4035 (5)0.071 (2)
H12A−0.53990.46360.43410.085*
C13−0.3872 (10)0.4703 (9)0.3782 (6)0.079 (3)
H13A−0.37110.54940.39010.095*
C14−0.3029 (10)0.4072 (8)0.3333 (6)0.071 (3)
H14A−0.22920.44070.31690.085*
C15−0.3377 (9)0.2900 (7)0.3149 (5)0.060 (2)
C16−0.4505 (10)0.2402 (8)0.3390 (5)0.070 (2)
H16A−0.47690.16580.32270.084*
C17−0.2499 (9)0.2250 (7)0.2652 (5)0.057 (2)
C18−0.1351 (9)0.0809 (8)0.1990 (6)0.063 (2)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Zn0.1219 (10)0.0225 (5)0.0593 (7)0.0009 (5)−0.0147 (6)0.0037 (5)
Cl10.134 (2)0.0377 (12)0.0743 (17)0.0062 (14)−0.0046 (16)−0.0073 (11)
Cl20.134 (2)0.0332 (11)0.0712 (16)−0.0054 (13)−0.0253 (15)0.0062 (11)
S10.134 (2)0.0210 (10)0.0646 (15)0.0045 (12)−0.0170 (15)0.0042 (10)
S20.146 (3)0.0255 (11)0.0671 (16)−0.0043 (13)−0.0155 (16)0.0022 (11)
N10.114 (7)0.035 (4)0.046 (4)−0.009 (4)−0.003 (4)0.001 (3)
N20.114 (7)0.022 (3)0.059 (5)0.010 (4)−0.013 (5)−0.003 (3)
N30.159 (9)0.024 (4)0.066 (6)−0.001 (5)−0.011 (6)0.004 (4)
N40.084 (5)0.037 (3)0.064 (4)−0.002 (3)−0.003 (4)−0.001 (3)
N50.095 (5)0.033 (3)0.055 (4)0.004 (3)−0.002 (4)0.000 (3)
N60.130 (8)0.025 (4)0.110 (7)0.000 (4)−0.002 (6)−0.008 (4)
C10.130 (11)0.082 (9)0.130 (12)0.000 (8)0.006 (9)−0.015 (9)
C20.125 (10)0.058 (6)0.064 (6)−0.028 (6)0.014 (6)0.005 (5)
C30.127 (9)0.041 (5)0.072 (7)0.003 (6)−0.010 (7)−0.017 (5)
C40.146 (10)0.037 (5)0.047 (5)−0.014 (6)−0.032 (6)0.004 (4)
C50.074 (6)0.040 (5)0.090 (7)0.000 (4)−0.013 (5)0.007 (5)
C60.094 (8)0.049 (6)0.112 (9)−0.024 (6)−0.020 (7)0.029 (6)
C70.119 (10)0.055 (6)0.085 (8)−0.006 (7)−0.020 (7)0.019 (6)
C80.131 (9)0.030 (4)0.052 (5)−0.009 (5)−0.030 (6)0.008 (4)
C90.129 (9)0.024 (4)0.051 (6)−0.002 (5)−0.022 (6)0.002 (4)
C100.0920.0920.0920.0000.0000.000
C110.072 (5)0.059 (5)0.077 (6)−0.006 (4)−0.020 (4)0.004 (4)
C120.084 (6)0.060 (5)0.069 (6)0.007 (4)−0.007 (4)−0.007 (4)
C130.091 (6)0.056 (5)0.090 (6)0.001 (4)−0.004 (5)−0.013 (5)
C140.094 (6)0.043 (4)0.076 (6)−0.002 (4)−0.002 (5)−0.002 (4)
C150.094 (5)0.037 (4)0.049 (5)0.017 (4)−0.011 (4)−0.004 (4)
C160.105 (6)0.045 (4)0.061 (5)−0.003 (4)−0.014 (4)0.002 (4)
C170.094 (5)0.034 (4)0.043 (4)−0.003 (4)−0.006 (4)−0.007 (3)
C180.074 (5)0.037 (4)0.077 (5)0.003 (4)−0.025 (4)−0.004 (4)
Geometric parameters (Å, °) top
Zn—Cl12.223 (3)C3—H3A0.9300
Zn—Cl22.270 (3)C4—C51.414 (12)
Zn—N22.056 (6)C4—C81.505 (14)
Zn—N52.089 (8)C5—C61.446 (14)
S1—C81.698 (11)C5—H5A0.9300
S1—C91.748 (9)C6—C71.328 (15)
S2—C181.699 (11)C6—H6A0.9300
S2—C171.753 (8)C7—H7A0.9300
N1—N21.410 (8)C9—N31.234 (13)
N1—C81.298 (11)C10—C111.485 (14)
N2—C91.355 (12)C10—H10A0.9600
N3—H3B0.8600C10—H10B0.9600
N3—H3C0.8600C10—H10C0.9600
N4—C171.250 (11)C11—C161.324 (11)
N5—N41.353 (10)C11—C121.370 (13)
N5—C181.344 (11)C12—C131.302 (14)
N6—H6B0.8600C12—H12A0.9300
N6—H6C0.8600C13—C141.409 (13)
C1—C21.478 (16)C13—H13A0.9300
C1—H1B0.9600C14—C151.408 (12)
C1—H1C0.9600C14—H14A0.9300
C1—H1D0.9600C15—C161.411 (13)
C2—C31.383 (14)C15—C171.494 (12)
C2—C71.411 (15)C16—H16A0.9300
C3—C41.402 (15)C18—N61.357 (12)
N2—Zn—N5111.8 (3)C7—C6—H6A119.7
N2—Zn—Cl1116.5 (2)C5—C6—H6A119.7
N5—Zn—Cl1105.8 (2)C6—C7—C2125.6 (12)
N2—Zn—Cl2105.5 (2)C6—C7—H7A117.2
N5—Zn—Cl2101.7 (2)C2—C7—H7A117.2
Cl1—Zn—Cl2114.67 (12)N1—C8—C4119.3 (10)
C8—S1—C988.6 (5)N1—C8—S1118.0 (8)
C18—S2—C1786.3 (4)C4—C8—S1122.7 (7)
C8—N1—N2108.2 (8)N3—C9—N2126.2 (9)
C9—N2—N1115.8 (7)N3—C9—S1124.4 (8)
C9—N2—Zn131.5 (6)N2—C9—S1109.4 (8)
N1—N2—Zn111.7 (5)C11—C10—H10A109.5
C9—N3—H3B120.0C11—C10—H10B109.5
C9—N3—H3C120.0H10A—C10—H10B109.5
H3B—N3—H3C120.0C11—C10—H10C109.5
C17—N4—N5112.9 (7)H10A—C10—H10C109.5
C18—N5—N4112.7 (8)H10B—C10—H10C109.5
C18—N5—Zn130.8 (7)C16—C11—C12122.4 (10)
N4—N5—Zn116.0 (5)C16—C11—C10114.8 (10)
C18—N6—H6B120.0C12—C11—C10122.4 (10)
C18—N6—H6C120.0C13—C12—C11121.7 (10)
H6B—N6—H6C120.0C13—C12—H12A119.2
C2—C1—H1B109.5C11—C12—H12A119.2
C2—C1—H1C109.5C12—C13—C14121.3 (10)
H1B—C1—H1C109.5C12—C13—H13A119.3
C2—C1—H1D109.5C14—C13—H13A119.3
H1B—C1—H1D109.5C15—C14—C13115.5 (10)
H1C—C1—H1D109.5C15—C14—H14A122.3
C3—C2—C7113.3 (11)C13—C14—H14A122.3
C3—C2—C1121.8 (10)C14—C15—C16122.0 (9)
C7—C2—C1124.9 (11)C14—C15—C17115.2 (9)
C2—C3—C4125.1 (10)C16—C15—C17122.7 (8)
C2—C3—H3A117.5C11—C16—C15116.6 (9)
C4—C3—H3A117.5C11—C16—H16A121.7
C3—C4—C5119.2 (10)C15—C16—H16A121.7
C3—C4—C8125.1 (9)N4—C17—C15124.6 (8)
C5—C4—C8115.7 (10)N4—C17—S2115.1 (7)
C4—C5—C6116.1 (10)C15—C17—S2120.2 (7)
C4—C5—H5A121.9N5—C18—N6121.9 (9)
C6—C5—H5A121.9N5—C18—S2113.0 (7)
C7—C6—C5120.7 (10)N6—C18—S2125.1 (7)
N5—Zn—N2—C925.7 (10)C9—S1—C8—C4−179.4 (8)
Cl1—Zn—N2—C9147.6 (8)N1—N2—C9—N3−177.0 (10)
Cl2—Zn—N2—C9−84.0 (9)Zn—N2—C9—N3−9.3 (16)
N5—Zn—N2—N1−166.2 (5)N1—N2—C9—S10.3 (10)
Cl1—Zn—N2—N1−44.4 (6)Zn—N2—C9—S1167.9 (5)
Cl2—Zn—N2—N184.1 (5)C8—S1—C9—N3176.8 (10)
N2—Zn—N5—C18156.5 (8)C8—S1—C9—N2−0.5 (7)
Cl1—Zn—N5—C1828.7 (9)C16—C11—C12—C13−4.5 (13)
Cl2—Zn—N5—C18−91.4 (8)C10—C11—C12—C13−177.0 (10)
N2—Zn—N5—N4−32.2 (7)C11—C12—C13—C14−1.7 (13)
Cl1—Zn—N5—N4−160.0 (6)C12—C13—C14—C153.2 (14)
Cl2—Zn—N5—N479.9 (6)C13—C14—C15—C160.9 (14)
C8—N1—N2—C90.2 (11)C13—C14—C15—C17178.1 (8)
C8—N1—N2—Zn−169.9 (6)C12—C11—C16—C158.2 (14)
C18—N5—N4—C17−1.7 (12)C10—C11—C16—C15−178.8 (9)
Zn—N5—N4—C17−174.6 (6)C14—C15—C16—C11−6.5 (14)
C7—C2—C3—C4−1.0 (17)C17—C15—C16—C11176.6 (8)
C1—C2—C3—C4−179.3 (11)N5—N4—C17—C15178.4 (8)
C2—C3—C4—C52.6 (17)N5—N4—C17—S22.6 (11)
C2—C3—C4—C8−178.1 (10)C14—C15—C17—N4−11.5 (14)
C3—C4—C5—C6−1.8 (15)C16—C15—C17—N4165.6 (9)
C8—C4—C5—C6178.9 (9)C14—C15—C17—S2164.0 (7)
C4—C5—C6—C7−0.4 (16)C16—C15—C17—S2−18.8 (12)
C5—C6—C7—C22(2)C18—S2—C17—N4−2.2 (8)
C3—C2—C7—C6−1.5 (19)C18—S2—C17—C15−178.2 (8)
C1—C2—C7—C6176.8 (13)N4—N5—C18—N6179.1 (9)
C3—C4—C8—N1−0.5 (15)Zn—N5—C18—N6−9.4 (14)
C5—C4—C8—N1178.8 (9)N4—N5—C18—S20.0 (10)
C3—C4—C8—S1179.6 (8)Zn—N5—C18—S2171.5 (5)
C5—C4—C8—S1−1.1 (13)C17—S2—C18—N51.1 (7)
C9—S1—C8—N10.7 (8)C17—S2—C18—N6−178.0 (9)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N3—H3B···N40.862.012.864 (10)174
N3—H3C···Cl2i0.862.533.332 (8)156
N6—H6B···Cl10.862.533.320 (9)152
N6—H6C···Cl2ii0.862.603.345 (8)146
C5—H5A···S10.932.623.040 (10)108
C10—H10C···Cl2iii0.962.683.599 (12)161
C16—H16A···S20.932.853.184 (10)103
Symmetry codes: (i) −x, y+1/2, −z+1/2; (ii) −x, y−1/2, −z+1/2; (iii) x−1, y, z.
Table 1
Selected geometric parameters (Å, °) top
Zn—Cl12.223 (3)Zn—N22.056 (6)
Zn—Cl22.270 (3)Zn—N52.089 (8)
N2—Zn—N5111.8 (3)N2—Zn—Cl2105.5 (2)
N2—Zn—Cl1116.5 (2)N5—Zn—Cl2101.7 (2)
N5—Zn—Cl1105.8 (2)Cl1—Zn—Cl2114.67 (12)
Table 2
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N3—H3B···N40.862.012.864 (10)174
N3—H3C···Cl2i0.862.533.332 (8)156
N6—H6B···Cl10.862.533.320 (9)152
N6—H6C···Cl2ii0.862.603.345 (8)146
C5—H5A···S10.932.623.040 (10)108
C10—H10C···Cl2iii0.962.683.599 (12)161
C16—H16A···S20.932.853.184 (10)103
Symmetry codes: (i) −x, y+1/2, −z+1/2; (ii) −x, y−1/2, −z+1/2; (iii) x−1, y, z.
Acknowledgements top

The authors thank Professor Hua-Qin Wang, Analysis Centre, Nanjing University, for performin the X-ray crystallographic analysis.

references
References top

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