Bis[methyl 2-(2-pyridylmethyl­idene)hydrazinecarbodithio­ato]zinc(II)

In the title compound, [Zn(C₈H₈N₃S₂)₂], the Zn atom is coordinated by the two ligands in a tridentate manner, via the pyridyl N, the azomethine N and the thiol­ate S atom; the coordination geometry is distorted octa­hedral, with the two ligands in the mer configuration (two S atoms and two pyridyl N atoms are cis with respect to each other and the azomethine N atoms is trans). The mol­ecules are linked by C—H...S hydrogen bonds, forming a three-dimensional network structure.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.006 Å
• R factor = 0.034
• wR factor = 0.079
• Data-to-parameter ratio = 18.8

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       0.99
PLAT220_ALERT_2_C Large Non-Solvent    C     Ueq(max)/Ueq(min) ...       2.55 Ratio
PLAT222_ALERT_3_C Large Non-Solvent    H     Ueq(max)/Ueq(min) ...       3.03 Ratio
PLAT232_ALERT_2_C Hirshfeld Test Diff (M-X)  Zn1    -   S3      ..       6.91 su
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         C7
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for        C15
PLAT420_ALERT_2_C D-H Without Acceptor       N3     -   H3A    ...          ?
PLAT420_ALERT_2_C D-H Without Acceptor       N6     -   H6A    ...          ?
PLAT717_ALERT_1_C D...A   Unknown or Inconsistent Label ..........         SL

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           27.13
           From the CIF: _reflns_number_total               4584
           Count of symmetry unique reflns         2462
           Completeness (_total/calc)            186.19%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured      2122
           Fraction of Friedel pairs measured     0.862
           Are heavy atom types Z>Si present        yes
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature .        293 K
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          1

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   9 ALERT level C = Check and explain
   4 ALERT level G = General alerts; check

   3 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   6 ALERT type 2 Indicator that the structure model may be wrong or deficient
   2 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

The wide variety of biological activity exhibited by thiosemicarbazones (Kasuga et al., 2001) and Schiff bases derived from S-alkyldithiocarbazates (Akbar Ali et al., 2001) and their interesting coordination chemistry have stimulated considerable research interest in these compounds (Casas et al., 2000). Some Schiff bases of S-alkyl esters of dithiocarbazic acid and their complexes were found to display antifungal and antibacterial properties (Tarafder et al., 2003). Recently we reported the Co(II) complex of the S-containing Schiff base ligand methyl 2-pyridylmethylidenehydrazinecarbodithioate (NNS^-) (Lin et al., 2007). As a part of structural studies of compounds containing the sulfur-nitrogen chelating ligand (Chen et al., 2003a,b), we report here the synthesis and structure of the compound, bis(methyl 2-pyridylmethylidenehydrazinecarbodithioato)zinc(II), Zn(NNS)₂.

The Zn atom is six-coordinated by the two tridentate NNS^- anions in a distorted octahedral geometry (Fig. 1). The ligands chelate the Zn(II) ion via the pyridyl N, the azomethine N, and the thiolate S atoms in a mer-configuration with four five-membered rings. The two azomethine N atoms (N2 and N5) are trans to each other, while the sulfur atoms (S1 and S3) and pyridyl N atoms (N1 and N4) are in cis positions. The two almost planar ligands [maximum deviation from their least-squares planes is 0.038 (3) Å] approach the central Zn(II) atom in an orthogonal orientation. The pyridyl ring and the two five-membered chelate rings formed by each ligand display very small dihedral angles between the planes. For each ligand, the maximum dihedral angle of 2.5 (1)° is between two neighbouring five-membered chelate rings (viz. Zn1—S1—C7—N3—N2 and Zn1—N1—C5—C6—N2).

The molecules are linked by C—H···S hydrogen bonds. As shown in Fig. 2, each molecular unit forms four acceptor/donor hydrogen bonds with four neighboring molecular units. resulting in a three-dimensional network structure.

Related literature

For general background, see: Akbar Ali et al. (2001); Casas et al. (2000); Kasuga et al. (2001); Tarafder et al. (2003). For related structures, see: Chen et al. (2003a,b); Lin et al. (2007).

S2. Experimental

A solution of Zn(ClO₄)₂ (363 mg, 1.00 mmol) in CH₃OH (20 ml) was slowly added to a solution of methyl 2-pyridylmethylidenehydrazinecarbodithioate (HNNS) (410 mg, 1.95 mmol) in CH₃OH (10 ml). The resultant black-purple solution was stirred under N₂ for 2 h at 323 K and then filtered. After addition of diethyl ether (20 ml), the filtrate was cooled to 253 K. A microcrystalline solid was collected after 24 h and dried under vacuum (yield: 264 mg, 55%). Brown block-shaped crystals suitable for X-ray diffraction were obtained in 2 d by slow diffusion of diethyl ether into a dilute solution of the title complex in methanol. The assigned structure was substantiated by elemental analysis; calculated for C₁₆H₁₆N₆ZnS₄: C 39.51, H 3.30, N 17.29%; found: C 39.46, H 3.38, N 17.23%.

S3. Refinement

All H atoms were placed in idealized positions (C—H = 0.93 or 0.97 Å), and refined in the riding-model approximation. U_iso(H) = xU_eq(carrier atom), where x = 1.5 for methyl and 1.2 for all other H atoms.

Computing details

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT (Bruker, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Bruker, 1998); software used to prepare material for publication: SHELXTL (Bruker, 1998) and local programs.

Figures

	Fig. 1. The molecular structure of the title compound. Dispacement ellipsoids are drawn at the 30% probability level. Hydrogen atoms have been omitted for clarity.
	Fig. 2. A view of the three-dimensional molecular network parallel to (010), formed by weak intermolecular C—H···S hydrogen bonds (dotted lines). Hydrogen atoms not involved in hydrogen bonds have been omitted.

Bis[methyl 2-(2-pyridylmethylidene)hydrazinecarbodithioato]zinc(II)

Crystal data

[Zn(C8H8N3S2)2]	F(000) = 1000
Mr = 487.97	Dx = 1.525 Mg m^−3
Orthorhombic, Pna21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P2c-2n	Cell parameters from 5120 reflections
a = 18.630 (7) Å	θ = 2.8–26.8°
b = 9.160 (3) Å	µ = 1.56 mm^−1
c = 12.457 (4) Å	T = 293 K
V = 2125.8 (13) Å^3	Block, colorless
Z = 4	0.25 × 0.22 × 0.17 mm

Data collection

Bruker SMART CCD area-detector diffractometer	4584 independent reflections
Radiation source: fine-focus sealed tube	3257 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.028
ϕ and ω scans	θmax = 27.1°, θmin = 2.2°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −23→13
Tmin = 0.745, Tmax = 0.777	k = −11→11
11500 measured reflections	l = −15→15

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)] = 0.034	H-atom parameters constrained
wR(F^2) = 0.079	w = 1/[σ^2(Fo^2) + (0.0305P)^2 + 0.1243P] where P = (Fo^2 + 2Fc^2)/3
S = 1.04	(Δ/σ)max < 0.001
4584 reflections	Δρmax = 0.25 e Å^−3
244 parameters	Δρmin = −0.30 e Å^−3
1 restraint	Absolute structure: Flack (1983), 2122 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.013 (12)

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
Zn1	0.056290 (19)	0.37624 (4)	−0.00480 (4)	0.05017 (12)
S1	0.06703 (6)	0.16722 (11)	−0.12754 (9)	0.0649 (3)
S2	0.16269 (7)	0.12965 (14)	−0.30631 (10)	0.0782 (4)
S3	0.15974 (5)	0.33863 (11)	0.11758 (9)	0.0641 (3)
S4	0.16648 (8)	0.15980 (16)	0.30963 (11)	0.0885 (4)
N1	0.05862 (16)	0.6151 (3)	0.0248 (2)	0.0548 (9)
N2	0.11660 (15)	0.4672 (3)	−0.1347 (2)	0.0494 (7)
N3	0.14624 (17)	0.3833 (4)	−0.2142 (2)	0.0587 (8)
H3A	0.1757	0.4172	−0.2611	0.070*
N4	−0.06136 (14)	0.3920 (3)	−0.0321 (2)	0.0527 (8)
N5	0.00813 (14)	0.2761 (3)	0.1317 (2)	0.0468 (7)
N6	0.04532 (16)	0.2141 (3)	0.2144 (2)	0.0563 (8)
H6A	0.0252	0.1636	0.2642	0.068*
C1	0.0304 (2)	0.6883 (5)	0.1059 (4)	0.0695 (11)
H1A	−0.0021	0.6405	0.1504	0.083*
C2	0.0468 (3)	0.8328 (5)	0.1276 (4)	0.0782 (13)
H2A	0.0268	0.8802	0.1864	0.094*
C3	0.0925 (3)	0.9028 (5)	0.0616 (4)	0.0806 (13)
H3B	0.1043	0.9998	0.0746	0.097*
C4	0.1219 (2)	0.8307 (4)	−0.0255 (4)	0.0708 (12)
H4A	0.1532	0.8780	−0.0723	0.085*
C5	0.1034 (2)	0.6868 (4)	−0.0407 (3)	0.0519 (9)
C6	0.13319 (19)	0.6008 (4)	−0.1282 (3)	0.0540 (9)
H6B	0.1638	0.6431	−0.1783	0.065*
C7	0.1259 (2)	0.2492 (5)	−0.2121 (3)	0.0513 (10)
C8	0.2232 (3)	0.2385 (6)	−0.3797 (5)	0.123 (2)
H8A	0.2461	0.1801	−0.4337	0.185*
H8B	0.2589	0.2776	−0.3320	0.185*
H8C	0.1976	0.3172	−0.4133	0.185*
C9	−0.0957 (2)	0.4483 (5)	−0.1153 (4)	0.0715 (11)
H9A	−0.0695	0.4984	−0.1670	0.086*
C10	−0.1684 (2)	0.4357 (5)	−0.1283 (4)	0.0832 (14)
H10A	−0.1906	0.4778	−0.1876	0.100*
C11	−0.2080 (2)	0.3619 (5)	−0.0549 (4)	0.0846 (15)
H11A	−0.2573	0.3521	−0.0632	0.102*
C12	−0.1735 (2)	0.3019 (5)	0.0324 (4)	0.0729 (12)
H12A	−0.1993	0.2519	0.0848	0.087*
C13	−0.09986 (19)	0.3174 (4)	0.0405 (3)	0.0529 (9)
C14	−0.05961 (18)	0.2558 (4)	0.1289 (3)	0.0543 (9)
H14A	−0.0826	0.2026	0.1824	0.065*
C15	0.1136 (2)	0.2385 (4)	0.2107 (3)	0.0535 (10)
C16	0.1042 (3)	0.0692 (7)	0.3960 (4)	0.131 (2)
H16A	0.1298	0.0223	0.4533	0.197*
H16B	0.0781	−0.0027	0.3558	0.197*
H16C	0.0713	0.1393	0.4253	0.197*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Zn1	0.0438 (2)	0.0553 (2)	0.0514 (2)	−0.00346 (17)	0.0087 (2)	0.0044 (2)
S1	0.0754 (7)	0.0579 (6)	0.0615 (6)	−0.0133 (5)	0.0076 (6)	−0.0041 (5)
S2	0.0750 (8)	0.0874 (9)	0.0721 (7)	0.0010 (6)	0.0107 (6)	−0.0295 (6)
S3	0.0393 (5)	0.0865 (7)	0.0665 (6)	0.0000 (5)	0.0002 (5)	−0.0022 (6)
S4	0.0793 (9)	0.0942 (9)	0.0921 (9)	0.0049 (7)	−0.0400 (8)	0.0142 (7)
N1	0.0497 (16)	0.0497 (16)	0.065 (3)	0.0043 (15)	0.0092 (15)	−0.0022 (14)
N2	0.0492 (16)	0.053 (2)	0.0462 (16)	−0.0006 (14)	0.0097 (14)	0.0008 (15)
N3	0.0558 (19)	0.071 (2)	0.0496 (18)	−0.0080 (16)	0.0192 (15)	−0.0006 (16)
N4	0.0441 (16)	0.0578 (18)	0.056 (2)	−0.0011 (14)	0.0030 (14)	0.0111 (14)
N5	0.0418 (17)	0.0534 (17)	0.0451 (15)	−0.0013 (13)	0.0030 (14)	0.0051 (14)
N6	0.057 (2)	0.065 (2)	0.0474 (17)	−0.0068 (15)	−0.0047 (15)	0.0106 (15)
C1	0.066 (3)	0.073 (3)	0.070 (3)	0.007 (2)	0.016 (2)	−0.002 (2)
C2	0.097 (3)	0.068 (3)	0.070 (3)	0.021 (2)	0.008 (3)	−0.011 (2)
C3	0.101 (4)	0.058 (3)	0.083 (3)	0.007 (3)	−0.005 (3)	−0.009 (2)
C4	0.080 (3)	0.057 (2)	0.076 (4)	−0.004 (2)	0.002 (2)	0.005 (2)
C5	0.051 (2)	0.044 (2)	0.060 (2)	0.0033 (17)	−0.0019 (17)	0.0037 (16)
C6	0.056 (2)	0.052 (2)	0.055 (2)	−0.0081 (17)	0.0097 (19)	0.0076 (18)
C7	0.051 (2)	0.058 (3)	0.045 (2)	−0.0007 (19)	−0.0046 (16)	−0.0083 (18)
C8	0.119 (4)	0.148 (5)	0.103 (4)	−0.015 (4)	0.053 (4)	−0.024 (4)
C9	0.060 (3)	0.079 (3)	0.076 (3)	0.000 (2)	−0.003 (2)	0.026 (3)
C10	0.066 (3)	0.089 (3)	0.095 (3)	0.001 (2)	−0.026 (3)	0.032 (3)
C11	0.047 (2)	0.093 (4)	0.114 (4)	−0.004 (2)	−0.018 (3)	0.023 (3)
C12	0.048 (2)	0.090 (3)	0.080 (3)	−0.019 (2)	0.002 (2)	0.016 (2)
C13	0.039 (2)	0.060 (2)	0.059 (2)	0.0024 (17)	0.0026 (17)	0.0065 (18)
C14	0.045 (2)	0.069 (2)	0.049 (2)	−0.0080 (17)	0.0058 (19)	0.0063 (18)
C15	0.051 (2)	0.056 (3)	0.054 (2)	0.0061 (19)	−0.0101 (19)	−0.0152 (17)
C16	0.158 (6)	0.146 (5)	0.090 (4)	−0.045 (4)	−0.054 (4)	0.052 (4)

Geometric parameters (Å, º)

Zn1—N5	2.130 (3)	C1—H1A	0.9300
Zn1—N2	2.139 (3)	C2—C3	1.346 (7)
Zn1—N1	2.219 (3)	C2—H2A	0.9300
Zn1—N4	2.223 (3)	C3—C4	1.384 (6)
Zn1—S1	2.4584 (13)	C3—H3B	0.9300
Zn1—S3	2.4814 (13)	C4—C5	1.376 (5)
S1—C7	1.697 (4)	C4—H4A	0.9300
S2—C7	1.744 (4)	C5—C6	1.456 (5)
S2—C8	1.761 (5)	C6—H6B	0.9300
S3—C15	1.710 (4)	C8—H8A	0.9600
S4—C15	1.735 (4)	C8—H8B	0.9600
S4—C16	1.786 (6)	C8—H8C	0.9600
N1—C1	1.321 (5)	C9—C10	1.368 (5)
N1—C5	1.339 (4)	C9—H9A	0.9300
N2—C6	1.264 (4)	C10—C11	1.356 (6)
N2—N3	1.370 (4)	C10—H10A	0.9300
N3—C7	1.286 (5)	C11—C12	1.377 (6)
N3—H3A	0.8600	C11—H11A	0.9300
N4—C9	1.323 (5)	C12—C13	1.384 (5)
N4—C13	1.341 (4)	C12—H12A	0.9300
N5—C14	1.276 (4)	C13—C14	1.447 (5)
N5—N6	1.365 (4)	C14—H14A	0.9300
N6—C15	1.293 (4)	C16—H16A	0.9600
N6—H6A	0.8600	C16—H16B	0.9600
C1—C2	1.385 (6)	C16—H16C	0.9600
N5—Zn1—N2	173.15 (11)	C5—C4—C3	117.7 (4)
N5—Zn1—N1	107.46 (11)	C5—C4—H4A	121.1
N2—Zn1—N1	74.43 (11)	C3—C4—H4A	121.1
N5—Zn1—N4	74.61 (10)	N1—C5—C4	122.9 (4)
N2—Zn1—N4	112.15 (11)	N1—C5—C6	115.4 (3)
N1—Zn1—N4	88.90 (11)	C4—C5—C6	121.7 (4)
N5—Zn1—S1	101.26 (8)	N2—C6—C5	118.6 (3)
N2—Zn1—S1	77.89 (8)	N2—C6—H6B	120.7
N1—Zn1—S1	150.43 (8)	C5—C6—H6B	120.7
N4—Zn1—S1	92.05 (8)	N3—C7—S1	128.7 (3)
N5—Zn1—S3	77.11 (8)	N3—C7—S2	118.1 (3)
N2—Zn1—S3	96.37 (9)	S1—C7—S2	113.2 (2)
N1—Zn1—S3	91.11 (8)	S2—C8—H8A	109.5
N4—Zn1—S3	150.32 (8)	S2—C8—H8B	109.5
S1—Zn1—S3	102.17 (4)	H8A—C8—H8B	109.5
C7—S1—Zn1	95.42 (14)	S2—C8—H8C	109.5
C7—S2—C8	104.2 (2)	H8A—C8—H8C	109.5
C15—S3—Zn1	95.79 (13)	H8B—C8—H8C	109.5
C15—S4—C16	104.6 (2)	N4—C9—C10	122.6 (4)
C1—N1—C5	117.7 (3)	N4—C9—H9A	118.7
C1—N1—Zn1	128.3 (3)	C10—C9—H9A	118.7
C5—N1—Zn1	113.2 (2)	C11—C10—C9	120.0 (4)
C6—N2—N3	119.4 (3)	C11—C10—H10A	120.0
C6—N2—Zn1	117.2 (2)	C9—C10—H10A	120.0
N3—N2—Zn1	122.7 (2)	C10—C11—C12	118.6 (4)
C7—N3—N2	113.8 (3)	C10—C11—H11A	120.7
C7—N3—H3A	123.1	C12—C11—H11A	120.7
N2—N3—H3A	123.1	C11—C12—C13	118.6 (4)
C9—N4—C13	117.9 (3)	C11—C12—H12A	120.7
C9—N4—Zn1	128.5 (3)	C13—C12—H12A	120.7
C13—N4—Zn1	113.0 (2)	N4—C13—C12	122.3 (4)
C14—N5—N6	117.5 (3)	N4—C13—C14	115.8 (3)
C14—N5—Zn1	117.2 (2)	C12—C13—C14	122.0 (4)
N6—N5—Zn1	124.6 (2)	N5—C14—C13	118.5 (3)
C15—N6—N5	113.6 (3)	N5—C14—H14A	120.8
C15—N6—H6A	123.2	C13—C14—H14A	120.8
N5—N6—H6A	123.2	N6—C15—S3	127.7 (3)
N1—C1—C2	123.1 (4)	N6—C15—S4	117.5 (3)
N1—C1—H1A	118.5	S3—C15—S4	114.8 (2)
C2—C1—H1A	118.5	S4—C16—H16A	109.5
C3—C2—C1	118.4 (4)	S4—C16—H16B	109.5
C3—C2—H2A	120.8	H16A—C16—H16B	109.5
C1—C2—H2A	120.8	S4—C16—H16C	109.5
C2—C3—C4	120.2 (4)	H16A—C16—H16C	109.5
C2—C3—H3B	119.9	H16B—C16—H16C	109.5
C4—C3—H3B	119.9

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2A···Sl^i	0.93	2.94	3.715 (3)	142
C12—H12A···S3^ii	0.93	2.79	3.526 (4)	138

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