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Acta Crystallogr Sect E Struct Rep Online. 2010 November 1; 66(Pt 11): m1448.
Published online 2010 October 23. doi:  10.1107/S160053681004119X
PMCID: PMC3009362

Dichloridobis(1-ethyl-2,6-dimethyl­pyridinium-4-olate-κO)zinc(II)

Abstract

In the title compound, [ZnCl2(C9H13NO)2], the ZnII ion is coordinated by two Cl anions and two O atoms of two zwitterionic organic ligands in a distorted tetra­hedral arrangement. In the crystal, mol­ecules are linked into sheets parallel to the bc plane by C—H(...)Cl and C—H(...)O hydrogen bonds and weak π–π inter­actions [centroid–centroid distance = 3.669 (1) Å].

Related literature

For general background to pyridinium compounds, see: Anwar et al. (1997 [triangle], 1999 [triangle]); Damiano et al. (2007 [triangle]); Darensbourg et al. (2003 [triangle]); Mootz & Wusson (1981 [triangle]). For hydrogen-bond motifs, see: Bernstein et al. (1995 [triangle]). For the preparation of 1-ethyl-2,6-dimethyl-4(1H)-pyridinone trihydrate, see: Garratt (1963 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-m1448-scheme1.jpg

Experimental

Crystal data

  • [ZnCl2(C9H13NO)2]
  • M r = 438.68
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-m1448-efi1.jpg
  • a = 30.365 (2) Å
  • b = 8.5366 (6) Å
  • c = 15.7982 (12) Å
  • β = 94.281 (4)°
  • V = 4083.7 (5) Å3
  • Z = 8
  • Mo Kα radiation
  • μ = 1.48 mm−1
  • T = 293 K
  • 0.25 × 0.25 × 0.23 mm

Data collection

  • Bruker SMART APEXII area-detector diffractometer
  • Absorption correction: multi-scan (SADABS, Bruker, 2008 [triangle]) T min = 0.709, T max = 0.727
  • 19140 measured reflections
  • 5069 independent reflections
  • 4248 reflections with I > 2σ(I)
  • R int = 0.042

Refinement

  • R[F 2 > 2σ(F 2)] = 0.031
  • wR(F 2) = 0.084
  • S = 0.99
  • 5069 reflections
  • 233 parameters
  • H-atom parameters constrained
  • Δρmax = 0.61 e Å−3
  • Δρmin = −0.56 e Å−3

Data collection: APEX2 (Bruker, 2008 [triangle]); cell refinement: SAINT (Bruker, 2008 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 (Farrugia, 1997 [triangle]); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009 [triangle]).

Table 1
Selected bond lengths (Å)
Table 2
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S160053681004119X/ci5172sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S160053681004119X/ci5172Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

MT and AP thank the UGC, India, for financial support in the form of a Research Fellowship in Science for Meritorious Students.

supplementary crystallographic information

Comment

Organic pyridinium salts have been widely used as guest molecules in the construction of supramolecular architecture in the field of chemistry (Damiano et al., 2007). Pyridinium cations are good candidates for second-harmonic generation (SHG) materials because they possess large hyperpolarizabilities (β) irrespective of the short cutoff wavelength. Since pyridinium cations are ionic species, they possess an easy tunability into noncentrosymmetric structures by changing counter anions (Anwar et al., 1997, 1999). The zinc halides substituted in pyridines lead to a variety of complexes involving zinc centers and were shown to be catalytically active for the coupling of carbon dioxide and epoxides to provide high molecular weight polycarbonates and cyclic carbonates (Darensbourg et al., 2003). As a part of our interest, we report here the crystal structure of the title pyridinium dichlorozinc(II) complex.

In the title molecule (Fig. 1), the ZnII atom is coordinated by a pair of pyridinium oxide group and terminal halide ions in a distorted tetrahedral arrangement. The organic ligand exists in a zwitterionic structure, involving a conjugated pyridinium fragment. The C atoms of methyl substituents at C2, C6, C12 and C16 lie in the plane of the corresponding pyridinium rings, which are evident from the C9—C2—N1—C6 [176.99 (16)°], C10—C6—N1—C2 [-175.51 (17)°], C19—C12—N11—C16 [178.46 (18)°] and C20—C16—N11—C12 [-178.4 (2)°] torsion angles. The C—C bond of the ethyl groups attached at N1 and N11 are approximately perpendicular to the attached pyridinium ring, which can be seen from the C8—C7—N1—C2 [93.7 (2)°] and C18—C17—N11—C12 [90.0 (2)°] torsion angles. The sum of the bond angles around the protonated nitrogen atoms N1 [360.0°] and N11 [359.99°] of both the pyridinium rings is in accordance with sp2 character. Due to protonation of N1 and N11 atoms of the pyridinium rings, the C2—N1—C6 and C12—N11—C16 angles are widened in comparison with the literature value (Mootz & Wusson, 1981). The pyridinium rings are planar and oriented each other at an angle of 67.79 (8)°.

The packing of the molecules in the unit cell is promoted by the existence of weak C—H···O, C—H···Cl and π···π types of intermolecular interactions. The C8—H8A···O1 interaction leads to the formation of a centrosymmetric R22(16) dimer (Bernstein et al., 1995). The Cl1 atom acts as an acceptor in a linear fashion for the methyl group hydrogen from the neighbouring molecule [Fig. 2 and Table 2]. The C13—H13···Cl2 intermolecular interaction also contributes to the crystal packing, which form zigzag chains along the c axis. The crystal structure is further augmented by π···π interaction between adjacent pyridinium rings [Cg1(x, y, z)···Cg1(-x, y, 1/2-z) = 3.669 (1) Å; where Cg1 is the centroid of the (N1-C6) ring, Fig.2].

Experimental

1-Ethyl-2,6-dimethyl-4(1H)pyridinone trihydrate (EDMP.3H2O) was synthesized according to the reported method (Garratt, 1963). The title complex was prepared by the reaction of ZnCl2 with EDMP.3H2O in a 1:2 molar ratio in aqueous medium. Single crystals were harvested after a typical growth period of 15 days from a saturated aqueous solution at 303 K by slow evaporation of the solvent.

Refinement

H atoms were positioned geometrically (C-H = 0.93-0.97 Å) and allowed to ride on their parent atoms, with Uiso(H) = 1.5Ueq(C) for methyl H and 1.2Ueq(C) for other H atoms.

Figures

Fig. 1.
The molecular structure of the title compound, showing 50% probability displacement ellipsoids.
Fig. 2.
The crystal packing of the title compound. H atoms not involved in hydrogen bonding (dashed lines) have been omitted for clarity.

Crystal data

[ZnCl2(C9H13NO)2]F(000) = 1824
Mr = 438.68Dx = 1.427 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 5069 reflections
a = 30.365 (2) Åθ = 1.3–28.3°
b = 8.5366 (6) ŵ = 1.48 mm1
c = 15.7982 (12) ÅT = 293 K
β = 94.281 (4)°Block, yellow
V = 4083.7 (5) Å30.25 × 0.25 × 0.23 mm
Z = 8

Data collection

Bruker SMART APEXII area-detector diffractometer5069 independent reflections
Radiation source: fine-focus sealed tube4248 reflections with I > 2σ(I)
graphiteRint = 0.042
ω and [var phi] scansθmax = 28.3°, θmin = 1.3°
Absorption correction: multi-scan (SADABS, Bruker, 2008)h = −40→40
Tmin = 0.709, Tmax = 0.727k = −11→10
19140 measured reflectionsl = −21→20

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.031H-atom parameters constrained
wR(F2) = 0.084w = 1/[σ2(Fo2) + (0.0343P)2 + 3.3394P] where P = (Fo2 + 2Fc2)/3
S = 0.99(Δ/σ)max = 0.001
5069 reflectionsΔρmax = 0.61 e Å3
233 parametersΔρmin = −0.56 e Å3
0 restraintsExtinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.00082 (11)

Special details

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)

xyzUiso*/Ueq
C2−0.01906 (5)1.0155 (2)0.10794 (11)0.0359 (4)
C30.01997 (6)0.9693 (2)0.14837 (11)0.0374 (4)
H30.02550.86290.15580.045*
C40.05235 (5)1.0787 (2)0.17944 (11)0.0364 (4)
C50.04059 (5)1.2375 (2)0.16743 (12)0.0383 (4)
H50.06031.31450.18800.046*
C60.00144 (6)1.2821 (2)0.12668 (11)0.0377 (4)
C7−0.07005 (6)1.2200 (3)0.04757 (12)0.0466 (4)
H7A−0.07971.13750.00820.056*
H7B−0.06461.31310.01470.056*
C8−0.10658 (6)1.2540 (3)0.10526 (14)0.0568 (5)
H8A−0.11111.16390.13990.085*
H8B−0.13341.27770.07150.085*
H8C−0.09841.34190.14090.085*
C9−0.05273 (7)0.8962 (3)0.07675 (14)0.0507 (5)
H9A−0.08100.92410.09560.076*
H9B−0.04420.79490.09880.076*
H9C−0.05450.89310.01590.076*
C10−0.00998 (7)1.4522 (2)0.11818 (15)0.0554 (5)
H10A−0.03411.47550.15200.083*
H10B−0.01831.47590.05980.083*
H10C0.01521.51420.13740.083*
C120.26273 (6)0.9691 (2)0.45067 (12)0.0416 (4)
C130.21875 (6)0.9588 (2)0.42739 (12)0.0419 (4)
H130.19870.99300.46500.050*
C140.20270 (6)0.8981 (2)0.34832 (11)0.0391 (4)
C150.23516 (6)0.8424 (2)0.29655 (13)0.0459 (4)
H150.22630.79640.24470.055*
C160.27915 (6)0.8540 (2)0.32029 (13)0.0434 (4)
C170.34104 (6)0.9425 (2)0.41988 (14)0.0468 (4)
H17A0.34511.03630.45420.056*
H17B0.35610.95810.36860.056*
C180.36164 (8)0.8059 (3)0.46811 (18)0.0676 (7)
H18A0.34770.79250.52020.101*
H18B0.39260.82540.48050.101*
H18C0.35780.71270.43440.101*
C190.27833 (7)1.0377 (3)0.53495 (15)0.0652 (7)
H19A0.29341.13460.52640.098*
H19B0.29810.96570.56490.098*
H19C0.25341.05670.56760.098*
C200.31287 (8)0.7970 (4)0.26254 (16)0.0698 (7)
H20A0.29810.75090.21270.105*
H20B0.33150.72010.29160.105*
H20C0.33060.88360.24630.105*
Cl10.08868 (2)0.63005 (6)0.23807 (5)0.06526 (17)
Cl20.163428 (18)0.86170 (7)0.10513 (3)0.05362 (14)
N1−0.02813 (5)1.17136 (17)0.09508 (9)0.0364 (3)
N110.29302 (5)0.92018 (19)0.39652 (10)0.0401 (3)
O10.08947 (4)1.04133 (16)0.21754 (10)0.0509 (3)
O20.16095 (4)0.89431 (19)0.32761 (9)0.0514 (3)
Zn10.126091 (6)0.85132 (2)0.221676 (13)0.03522 (8)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C20.0331 (8)0.0397 (9)0.0349 (9)−0.0027 (7)0.0028 (6)−0.0047 (7)
C30.0367 (8)0.0331 (8)0.0420 (10)0.0009 (7)0.0001 (7)−0.0038 (7)
C40.0311 (8)0.0414 (9)0.0365 (9)0.0019 (7)0.0006 (6)−0.0082 (7)
C50.0337 (8)0.0372 (9)0.0442 (10)−0.0028 (7)0.0040 (7)−0.0086 (7)
C60.0366 (8)0.0377 (9)0.0395 (9)0.0019 (7)0.0082 (7)−0.0019 (7)
C70.0382 (9)0.0612 (12)0.0391 (10)0.0070 (8)−0.0048 (7)0.0064 (9)
C80.0358 (10)0.0771 (15)0.0569 (13)0.0145 (10)−0.0002 (9)0.0079 (11)
C90.0406 (10)0.0522 (11)0.0583 (13)−0.0106 (8)−0.0028 (9)−0.0086 (10)
C100.0540 (12)0.0411 (11)0.0712 (15)0.0064 (9)0.0054 (10)0.0025 (10)
C120.0338 (8)0.0507 (10)0.0400 (10)−0.0015 (7)0.0008 (7)−0.0080 (8)
C130.0310 (8)0.0549 (11)0.0399 (10)0.0011 (7)0.0034 (7)−0.0087 (8)
C140.0317 (8)0.0471 (10)0.0380 (9)0.0013 (7)0.0003 (7)−0.0002 (8)
C150.0391 (9)0.0613 (12)0.0366 (10)0.0061 (8)−0.0023 (7)−0.0105 (8)
C160.0363 (9)0.0532 (11)0.0408 (10)0.0074 (7)0.0042 (7)−0.0036 (8)
C170.0316 (8)0.0511 (11)0.0574 (12)−0.0015 (8)0.0010 (8)0.0057 (9)
C180.0505 (13)0.0731 (15)0.0773 (17)0.0136 (11)−0.0076 (11)0.0157 (13)
C190.0414 (11)0.0977 (19)0.0556 (13)−0.0049 (11)−0.0026 (9)−0.0305 (13)
C200.0456 (12)0.106 (2)0.0580 (14)0.0179 (12)0.0083 (10)−0.0213 (14)
Cl10.0609 (3)0.0442 (3)0.0936 (5)−0.0149 (2)0.0257 (3)−0.0035 (3)
Cl20.0553 (3)0.0670 (3)0.0395 (3)−0.0098 (2)0.0095 (2)0.0006 (2)
N10.0302 (7)0.0440 (8)0.0349 (8)0.0032 (6)0.0014 (5)−0.0004 (6)
N110.0280 (7)0.0478 (9)0.0439 (8)0.0019 (6)−0.0009 (6)−0.0009 (7)
O10.0375 (7)0.0462 (7)0.0660 (9)0.0066 (6)−0.0154 (6)−0.0122 (7)
O20.0296 (6)0.0840 (10)0.0399 (7)0.0028 (6)−0.0032 (5)−0.0090 (7)
Zn10.02879 (11)0.03822 (13)0.03829 (13)−0.00233 (7)0.00007 (8)−0.00281 (8)

Geometric parameters (Å, °)

C2—C31.362 (2)C12—C191.498 (3)
C2—N11.371 (2)C13—C141.406 (3)
C2—C91.500 (2)C13—H130.93
C3—C41.416 (2)C14—O21.286 (2)
C3—H30.93C14—C151.409 (3)
C4—O11.278 (2)C15—C161.364 (3)
C4—C51.412 (3)C15—H150.93
C5—C61.363 (2)C16—N111.368 (2)
C5—H50.93C16—C201.502 (3)
C6—N11.372 (2)C17—N111.490 (2)
C6—C101.496 (3)C17—C181.503 (3)
C7—N11.488 (2)C17—H17A0.97
C7—C81.515 (3)C17—H17B0.97
C7—H7A0.97C18—H18A0.96
C7—H7B0.97C18—H18B0.96
C8—H8A0.96C18—H18C0.96
C8—H8B0.96C19—H19A0.96
C8—H8C0.96C19—H19B0.96
C9—H9A0.96C19—H19C0.96
C9—H9B0.96C20—H20A0.96
C9—H9C0.96C20—H20B0.96
C10—H10A0.96C20—H20C0.96
C10—H10B0.96Cl1—Zn12.2292 (5)
C10—H10C0.96Cl2—Zn12.2349 (6)
C12—C131.361 (2)O1—Zn11.9649 (13)
C12—N111.367 (2)O2—Zn11.9472 (13)
C3—C2—N1120.57 (15)O2—C14—C15124.24 (17)
C3—C2—C9120.36 (17)C13—C14—C15115.41 (16)
N1—C2—C9119.07 (16)C16—C15—C14121.93 (18)
C2—C3—C4121.94 (16)C16—C15—H15119.0
C2—C3—H3119.0C14—C15—H15119.0
C4—C3—H3119.0C15—C16—N11120.19 (17)
O1—C4—C5120.54 (16)C15—C16—C20120.50 (19)
O1—C4—C3124.33 (17)N11—C16—C20119.30 (17)
C5—C4—C3115.12 (15)N11—C17—C18112.90 (17)
C6—C5—C4122.31 (16)N11—C17—H17A109.0
C6—C5—H5118.8C18—C17—H17A109.0
C4—C5—H5118.8N11—C17—H17B109.0
C5—C6—N1120.23 (16)C18—C17—H17B109.0
C5—C6—C10120.08 (17)H17A—C17—H17B107.8
N1—C6—C10119.67 (16)C17—C18—H18A109.5
N1—C7—C8112.78 (16)C17—C18—H18B109.5
N1—C7—H7A109.0H18A—C18—H18B109.5
C8—C7—H7A109.0C17—C18—H18C109.5
N1—C7—H7B109.0H18A—C18—H18C109.5
C8—C7—H7B109.0H18B—C18—H18C109.5
H7A—C7—H7B107.8C12—C19—H19A109.5
C7—C8—H8A109.5C12—C19—H19B109.5
C7—C8—H8B109.5H19A—C19—H19B109.5
H8A—C8—H8B109.5C12—C19—H19C109.5
C7—C8—H8C109.5H19A—C19—H19C109.5
H8A—C8—H8C109.5H19B—C19—H19C109.5
H8B—C8—H8C109.5C16—C20—H20A109.5
C2—C9—H9A109.5C16—C20—H20B109.5
C2—C9—H9B109.5H20A—C20—H20B109.5
H9A—C9—H9B109.5C16—C20—H20C109.5
C2—C9—H9C109.5H20A—C20—H20C109.5
H9A—C9—H9C109.5H20B—C20—H20C109.5
H9B—C9—H9C109.5C2—N1—C6119.74 (14)
C6—C10—H10A109.5C2—N1—C7120.04 (15)
C6—C10—H10B109.5C6—N1—C7120.21 (15)
H10A—C10—H10B109.5C12—N11—C16119.99 (15)
C6—C10—H10C109.5C12—N11—C17119.84 (15)
H10A—C10—H10C109.5C16—N11—C17120.15 (16)
H10B—C10—H10C109.5C4—O1—Zn1134.31 (12)
C13—C12—N11120.20 (16)C14—O2—Zn1133.29 (12)
C13—C12—C19120.27 (17)O2—Zn1—O198.22 (6)
N11—C12—C19119.51 (16)O2—Zn1—Cl1107.99 (5)
C12—C13—C14122.15 (17)O1—Zn1—Cl1114.29 (5)
C12—C13—H13118.9O2—Zn1—Cl2115.09 (4)
C14—C13—H13118.9O1—Zn1—Cl2105.10 (5)
O2—C14—C13120.34 (16)Cl1—Zn1—Cl2115.06 (2)
N1—C2—C3—C40.7 (3)C10—C6—N1—C74.0 (2)
C9—C2—C3—C4−179.34 (17)C8—C7—N1—C293.7 (2)
C2—C3—C4—O1−179.80 (18)C8—C7—N1—C6−85.9 (2)
C2—C3—C4—C51.7 (3)C13—C12—N11—C16−3.0 (3)
O1—C4—C5—C6179.59 (18)C19—C12—N11—C16178.4 (2)
C3—C4—C5—C6−1.8 (3)C13—C12—N11—C17175.60 (18)
C4—C5—C6—N1−0.4 (3)C19—C12—N11—C17−3.0 (3)
C4—C5—C6—C10178.01 (17)C15—C16—N11—C122.7 (3)
N11—C12—C13—C140.2 (3)C20—C16—N11—C12−178.4 (2)
C19—C12—C13—C14178.8 (2)C15—C16—N11—C17−175.92 (18)
C12—C13—C14—O2−178.01 (19)C20—C16—N11—C173.0 (3)
C12—C13—C14—C152.7 (3)C18—C17—N11—C1290.0 (2)
O2—C14—C15—C16177.7 (2)C18—C17—N11—C16−91.4 (2)
C13—C14—C15—C16−3.0 (3)C5—C4—O1—Zn1−160.08 (14)
C14—C15—C16—N110.4 (3)C3—C4—O1—Zn121.5 (3)
C14—C15—C16—C20−178.5 (2)C13—C14—O2—Zn1169.24 (15)
C3—C2—N1—C6−3.1 (3)C15—C14—O2—Zn1−11.6 (3)
C9—C2—N1—C6176.98 (17)C14—O2—Zn1—O1−127.09 (19)
C3—C2—N1—C7177.37 (16)C14—O2—Zn1—Cl1113.97 (19)
C9—C2—N1—C7−2.6 (2)C14—O2—Zn1—Cl2−16.1 (2)
C5—C6—N1—C22.9 (3)C4—O1—Zn1—O2−159.12 (19)
C10—C6—N1—C2−175.51 (17)C4—O1—Zn1—Cl1−45.1 (2)
C5—C6—N1—C7−177.53 (17)C4—O1—Zn1—Cl282.02 (19)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C8—H8A···O1i0.962.533.344 (3)143
C10—H10A···Cl1ii0.962.823.740 (2)162
C10—H10C···Cl1iii0.962.823.745 (2)162
C13—H13···Cl2iv0.932.823.709 (2)161

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: CI5172).

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