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Acta Cryst. (2008). E64, o798    [ doi:10.1107/S1600536808008258 ]

A charge-transfer salt, 3,5-dimethyl-1-(4-nitrobenzyl)pyridinium 7,7,8,8-tetracyanoquinodimethane

M. Wang, H.-B. Zhou and Y.-C. Chen

Abstract top

In the title salt, C14H15N2O2+·C12H4N4-, the asymmetric unit contains one cation and one anion. C-H...N and C-H...N and C-H...O hydrogen bonds and [pi]-[pi] stacking interactions (interplanar distance 3.845 Å) are found in the crystal structure.

Comment top

Recently, using benzylpyridinium derivatives ([RBzPy]+ where R represents a substituent group) with flexible molecular configuration as a counter-cation to control the arrangement of anions [M(mnt)2]- (M = Ni, Pd, Pt), a series of ion-pair compounds that show segregated columnar stacks of cations and anions has been prepared (Madalan et al., 2002; Ren, Chen et al., 2002; Ren et al., 2003; Ren, Meng et al., 2002). The radical of TCNQ also shows a planar arrangement and extended electronic structures that are similar to the [M(mnt)2]- ion, and has been extensively used to build molecular solids with low-dimensional conductivity and magnetic features, in which the electronic transport and magnetically coupled interactions can be achieved through π–π interactions between radicals along the direction of the radical stack column (Liu et al., 2005; Wang et al., 2006). This character of the TCNQ- ion prompted us to extend our research to a series of [RBzPy][TCNQ] compounds in order to gain more insight into the relationship between the intermolecular cooperation interactions and the magnetic properties of the compounds with low-dimensional structural features. In this paper, we report the crystal structure of the title compound.

The asymmetric unit contains one (C14H15N2O2)+ cation and one [C8H4(CN)4]- anion (Fig. 1). It stacks as completely segregated columns of TCNQ anions/molecules and 3,5-dimethyl-1-(4-nitrobenzyl)pyridinium cations, as illustrated by the projection along the crystallographic a axis in Fig. 2. The cation and anion columns are linked by hydrogen-bonding interactions. Within an anionic column, a strongly bound [(TCNQ)2]2- unit is formed, and adjacent units are displaced relative to each other along the direction of the shorter molecular axis of TCNQ. The benzene rings are parallel to each other. In a TCNQ column, the mean interplanar separations within two different overlapping pairs are 5.745 Å inter-dimer and 3.845 Å intra-dimer, respectively, indicating weak π–π stacking interactions. The (C14H15N2O2)+ cation has a Λ-shaped conformation, and the dihedral angles formed by the C4/C7/N2 plane with the benzene and pyridinium rings are 4.12 (11) and 80.45 (12)°, respectively.

Related literature top

For general background, see: Madalan et al. (2002); Ren, Chen et al. (2002); Ren et al. (2003); Ren, Meng et al. (2002). For related literature, see: Liu et al. (2005); Wang et al. (2006).

Experimental top

3,5-Dimethyl-1-(4-nitrobenzyl)pyridinium iodide was prepared by the direct combination of 1:1 molar equivalents of 3,5-dimethyl-1-(4-nitrobenzyl)pyridinium chloride and NaI in a warm solution in acetone at 313 K. A white precipitate was formed (NaCl), which was filtered off, and a white microcrystalline product was obtained by evaporating the filtrate. 1:2 Molar equivalents of 3,5-dimethyl-1-(4-nitrobenzyl)pyridinium iodide and TCNQ were mixed directly in a solution in methanol, and the mixture was refluxed for 12 h. The dark-green microcrystalline product which formed was filtered off, washed with MeOH and dried in vacuo. Single crystals of (I) suitable for structure analysis were obtained by diffusing diethyl ether into an acetonitrile solution of (I).

Refinement top

H atoms were positioned geometrically, with C—H = 0.93, 0.97 and 0.96 Å for aromatic, methylene and methyl H atoms, respectively, and constrained to ride on their parent atoms, with Uiso(H) = xUeq(C), where x = 1.5 for methyl H and x = 1.2 for all other H atoms.

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT-Plus (Bruker, 2000); data reduction: SAINT-Plus (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
[Figure 1] Fig. 1. The asymmetric unit, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 2] Fig. 2. A packing diagram for (I). Hydrogen bonds are shown as dashed lines.
[Figure 3] Fig. 3. A side-view of the one-dimensional anionic stack of (I).
3,5-dimethyl-1-(4-nitrobenzyl)pyridinium 7,7,8,8-tetracyanoquinodimethane top
Crystal data top
C14H15N2O2+·C12H4N4–Z = 2
Mr = 447.47F000 = 466
Triclinic, P1Dx = 1.289 Mg m−3
Hall symbol: -P 1Mo Kα radiation
λ = 0.71073 Å
a = 8.098 (2) ÅCell parameters from 3033 reflections
b = 9.137 (2) Åθ = 2.3–27.9º
c = 16.542 (4) ŵ = 0.09 mm−1
α = 76.194 (3)ºT = 293 (2) K
β = 75.951 (3)ºPillar, purple
γ = 86.933 (3)º0.18 × 0.12 × 0.10 mm
V = 1153.0 (5) Å3
Data collection top
Bruker SMART APEX CCD
diffractometer		3998 independent reflections
Radiation source: sealed tube3255 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.018
T = 293(2) Kθmax = 25.1º
φ and ω scansθmin = 2.3º
Absorption correction: multi-scan
(SADABS; Bruker, 2000)		h = −9→9
Tmin = 0.985, Tmax = 0.992k = −10→10
5765 measured reflectionsl = −19→16
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)] = 0.046H-atom parameters constrained
wR(F2) = 0.144  w = 1/[σ2(Fo2) + (0.0904P)2 + 0.1284P]
where P = (Fo2 + 2Fc2)/3
S = 1.00(Δ/σ)max < 0.001
3998 reflectionsΔρmax = 0.15 e Å−3
309 parametersΔρmin = −0.20 e Å−3
Primary atom site location: structure-invariant direct methodsExtinction correction: none
Crystal data top
C14H15N2O2+·C12H4N4–γ = 86.933 (3)º
Mr = 447.47V = 1153.0 (5) Å3
Triclinic, P1Z = 2
a = 8.098 (2) ÅMo Kα
b = 9.137 (2) ŵ = 0.09 mm−1
c = 16.542 (4) ÅT = 293 (2) K
α = 76.194 (3)º0.18 × 0.12 × 0.10 mm
β = 75.951 (3)º
Data collection top
Bruker SMART APEX CCD
diffractometer		3998 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2000)		3255 reflections with I > 2σ(I)
Tmin = 0.985, Tmax = 0.992Rint = 0.018
5765 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.046309 parameters
wR(F2) = 0.144H-atom parameters constrained
S = 1.00Δρmax = 0.15 e Å−3
3998 reflectionsΔρmin = −0.20 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 > 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
C10.3034 (2)−0.11674 (18)0.07248 (10)0.0532 (4)
C20.1837 (3)−0.0094 (3)0.06055 (17)0.0920 (8)
H20.0998−0.02280.03320.110*
C30.1875 (3)0.1190 (3)0.08930 (16)0.0863 (7)
H30.10660.19340.08050.104*
C40.30938 (19)0.13943 (17)0.13103 (9)0.0464 (4)
C50.4274 (2)0.02782 (18)0.14337 (11)0.0557 (4)
H50.50970.03920.17210.067*
C60.4257 (2)−0.10127 (18)0.11367 (11)0.0579 (4)
H60.5067−0.17610.12170.069*
C70.3015 (2)0.28325 (18)0.16136 (11)0.0513 (4)
H7A0.30250.36810.11310.062*
H7B0.19460.28550.20310.062*
C80.5758 (2)0.39025 (17)0.15325 (10)0.0506 (4)
H80.57800.43660.09640.061*
C90.7086 (2)0.41397 (18)0.18741 (10)0.0535 (4)
C100.6996 (2)0.34162 (18)0.27232 (11)0.0545 (4)
H100.78670.35630.29730.065*
C110.5642 (2)0.24809 (17)0.32079 (10)0.0502 (4)
C120.4356 (2)0.23031 (17)0.28237 (9)0.0481 (4)
H120.34300.16860.31340.058*
C130.8551 (3)0.5148 (3)0.13244 (14)0.0805 (6)
H13A0.89470.48650.07870.121*
H13B0.94600.50450.16130.121*
H13C0.81780.61770.12230.121*
C140.5536 (3)0.1662 (2)0.41234 (11)0.0665 (5)
H14A0.66360.16600.42450.100*
H14B0.51680.06430.42100.100*
H14C0.47350.21610.44990.100*
C150.8272 (2)0.8781 (2)0.25321 (12)0.0631 (5)
C160.9551 (2)1.0193 (2)0.32804 (11)0.0566 (4)
C170.8784 (2)0.88381 (18)0.32838 (10)0.0539 (4)
C180.8522 (2)0.76197 (17)0.40146 (10)0.0497 (4)
C190.9004 (2)0.77045 (17)0.47720 (10)0.0506 (4)
H190.95260.85780.47850.061*
C200.8724 (2)0.65455 (17)0.54774 (10)0.0502 (4)
H200.90580.66460.59610.060*
C210.7936 (2)0.51845 (17)0.54952 (10)0.0502 (4)
C220.7464 (2)0.50974 (18)0.47347 (11)0.0588 (4)
H220.69530.42210.47180.071*
C230.7742 (2)0.62636 (19)0.40311 (11)0.0581 (4)
H230.74090.61660.35470.070*
C240.7631 (2)0.39860 (18)0.62288 (10)0.0553 (4)
C250.7996 (2)0.41186 (19)0.70048 (11)0.0583 (4)
C260.6899 (3)0.2598 (2)0.62445 (11)0.0639 (5)
N10.3014 (2)−0.25176 (18)0.03913 (9)0.0650 (4)
N20.44324 (16)0.30155 (13)0.20044 (8)0.0456 (3)
N30.7848 (3)0.8728 (2)0.19242 (12)0.0903 (6)
N41.0142 (2)1.12948 (19)0.33055 (11)0.0752 (5)
N50.8270 (3)0.4254 (2)0.76315 (10)0.0802 (5)
N60.6314 (3)0.1475 (2)0.62508 (12)0.0907 (6)
O10.1827 (2)−0.2699 (2)0.00906 (11)0.0984 (5)
O20.4200 (2)−0.33952 (15)0.04148 (8)0.0797 (4)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0619 (10)0.0509 (9)0.0478 (9)−0.0093 (7)−0.0113 (7)−0.0133 (7)
C20.0824 (14)0.1014 (16)0.134 (2)0.0240 (12)−0.0685 (14)−0.0698 (15)
C30.0792 (14)0.0869 (14)0.1301 (19)0.0341 (11)−0.0692 (14)−0.0587 (14)
C40.0492 (8)0.0473 (8)0.0439 (8)−0.0011 (6)−0.0155 (6)−0.0082 (6)
C50.0644 (10)0.0535 (9)0.0587 (10)0.0069 (7)−0.0338 (8)−0.0135 (7)
C60.0739 (11)0.0473 (9)0.0563 (10)0.0070 (8)−0.0274 (8)−0.0089 (7)
C70.0539 (9)0.0485 (8)0.0569 (9)0.0028 (7)−0.0238 (7)−0.0125 (7)
C80.0615 (10)0.0445 (8)0.0447 (8)−0.0022 (7)−0.0143 (7)−0.0058 (6)
C90.0573 (10)0.0478 (8)0.0572 (9)−0.0040 (7)−0.0146 (8)−0.0135 (7)
C100.0587 (10)0.0546 (9)0.0595 (10)0.0006 (7)−0.0241 (8)−0.0207 (7)
C110.0617 (10)0.0477 (8)0.0453 (8)0.0049 (7)−0.0169 (7)−0.0156 (7)
C120.0552 (9)0.0449 (8)0.0443 (8)−0.0021 (6)−0.0115 (7)−0.0107 (6)
C130.0729 (13)0.0809 (14)0.0830 (14)−0.0252 (11)−0.0143 (11)−0.0090 (11)
C140.0828 (13)0.0734 (12)0.0456 (9)−0.0002 (9)−0.0220 (9)−0.0113 (8)
C150.0654 (11)0.0626 (11)0.0613 (11)0.0035 (8)−0.0258 (9)−0.0042 (8)
C160.0548 (10)0.0537 (10)0.0570 (10)0.0021 (8)−0.0132 (8)−0.0051 (7)
C170.0556 (9)0.0501 (9)0.0559 (9)0.0043 (7)−0.0179 (7)−0.0083 (7)
C180.0522 (9)0.0460 (8)0.0529 (9)0.0062 (7)−0.0153 (7)−0.0140 (7)
C190.0545 (9)0.0458 (8)0.0553 (9)0.0005 (7)−0.0146 (7)−0.0176 (7)
C200.0570 (9)0.0498 (8)0.0484 (9)0.0045 (7)−0.0149 (7)−0.0186 (7)
C210.0578 (9)0.0460 (8)0.0496 (9)0.0056 (7)−0.0141 (7)−0.0161 (7)
C220.0759 (11)0.0463 (9)0.0603 (10)−0.0065 (8)−0.0261 (8)−0.0129 (7)
C230.0762 (11)0.0518 (9)0.0544 (9)0.0000 (8)−0.0294 (8)−0.0137 (7)
C240.0677 (10)0.0481 (9)0.0509 (9)0.0010 (7)−0.0141 (8)−0.0130 (7)
C250.0734 (11)0.0492 (9)0.0490 (10)0.0027 (8)−0.0104 (8)−0.0097 (7)
C260.0795 (12)0.0543 (10)0.0566 (10)−0.0027 (9)−0.0187 (9)−0.0071 (8)
N10.0819 (11)0.0605 (9)0.0519 (8)−0.0165 (8)−0.0075 (7)−0.0163 (7)
N20.0523 (7)0.0422 (6)0.0459 (7)0.0010 (5)−0.0171 (6)−0.0121 (5)
N30.0981 (14)0.1037 (14)0.0760 (12)0.0055 (11)−0.0442 (11)−0.0116 (10)
N40.0802 (11)0.0611 (10)0.0811 (11)−0.0123 (8)−0.0199 (9)−0.0071 (8)
N50.1159 (15)0.0736 (11)0.0536 (9)0.0017 (10)−0.0239 (9)−0.0160 (8)
N60.1217 (16)0.0631 (11)0.0885 (13)−0.0249 (10)−0.0333 (11)−0.0059 (9)
O10.0935 (11)0.1097 (12)0.1151 (13)−0.0195 (9)−0.0270 (9)−0.0635 (10)
O20.1179 (12)0.0539 (7)0.0688 (8)0.0086 (8)−0.0227 (8)−0.0187 (6)
Geometric parameters (Å, °) top
C1—C21.356 (3)C13—H13B0.960
C1—C61.362 (2)C13—H13C0.960
C1—N11.469 (2)C14—H14A0.960
C2—C31.372 (3)C14—H14B0.960
C2—H20.930C14—H14C0.960
C3—C41.377 (2)C15—N31.151 (2)
C3—H30.930C15—C171.416 (2)
C4—C51.373 (2)C16—N41.151 (2)
C4—C71.508 (2)C16—C171.413 (2)
C5—C61.384 (2)C17—C181.416 (2)
C5—H50.930C18—C231.412 (2)
C6—H60.930C18—C191.419 (2)
C7—N21.4818 (19)C19—C201.357 (2)
C7—H7A0.970C19—H190.930
C7—H7B0.970C20—C211.419 (2)
C8—N21.343 (2)C20—H200.930
C8—C91.379 (2)C21—C241.408 (2)
C8—H80.930C21—C221.421 (2)
C9—C101.388 (2)C22—C231.359 (2)
C9—C131.509 (2)C22—H220.930
C10—C111.386 (2)C23—H230.930
C10—H100.930C24—C251.418 (2)
C11—C121.379 (2)C24—C261.420 (3)
C11—C141.505 (2)C25—N51.147 (2)
C12—N21.3442 (19)C26—N61.150 (2)
C12—H120.930N1—O11.220 (2)
C13—H13A0.960N1—O21.220 (2)
C2—C1—C6121.58 (16)H13A—C13—H13C109.5
C2—C1—N1118.90 (16)H13B—C13—H13C109.5
C6—C1—N1119.51 (16)C11—C14—H14A109.5
C1—C2—C3119.27 (16)C11—C14—H14B109.5
C1—C2—H2120.4H14A—C14—H14B109.5
C3—C2—H2120.4C11—C14—H14C109.5
C2—C3—C4121.06 (17)H14A—C14—H14C109.5
C2—C3—H3119.5H14B—C14—H14C109.5
C4—C3—H3119.5N3—C15—C17179.6 (2)
C5—C4—C3118.37 (15)N4—C16—C17177.63 (19)
C5—C4—C7124.51 (13)C16—C17—C15116.70 (15)
C3—C4—C7117.11 (14)C16—C17—C18120.87 (14)
C4—C5—C6120.97 (14)C15—C17—C18122.42 (15)
C4—C5—H5119.5C23—C18—C17121.56 (14)
C6—C5—H5119.5C23—C18—C19116.56 (14)
C1—C6—C5118.74 (15)C17—C18—C19121.88 (14)
C1—C6—H6120.6C20—C19—C18121.80 (14)
C5—C6—H6120.6C20—C19—H19119.1
N2—C7—C4113.85 (12)C18—C19—H19119.1
N2—C7—H7A108.8C19—C20—C21121.66 (14)
C4—C7—H7A108.8C19—C20—H20119.2
N2—C7—H7B108.8C21—C20—H20119.2
C4—C7—H7B108.8C24—C21—C20121.76 (14)
H7A—C7—H7B107.7C24—C21—C22121.76 (14)
N2—C8—C9121.24 (14)C20—C21—C22116.48 (14)
N2—C8—H8119.4C23—C22—C21121.60 (15)
C9—C8—H8119.4C23—C22—H22119.2
C8—C9—C10117.15 (15)C21—C22—H22119.2
C8—C9—C13119.71 (16)C22—C23—C18121.90 (15)
C10—C9—C13123.14 (16)C22—C23—H23119.1
C11—C10—C9121.71 (14)C18—C23—H23119.1
C11—C10—H10119.1C21—C24—C25121.48 (14)
C9—C10—H10119.1C21—C24—C26122.28 (14)
C12—C11—C10117.85 (14)C25—C24—C26116.22 (15)
C12—C11—C14119.55 (15)N5—C25—C24178.50 (19)
C10—C11—C14122.60 (15)N6—C26—C24179.5 (2)
N2—C12—C11120.51 (14)O1—N1—O2122.89 (16)
N2—C12—H12119.7O1—N1—C1118.57 (17)
C11—C12—H12119.7O2—N1—C1118.52 (15)
C9—C13—H13A109.5C8—N2—C12121.53 (13)
C9—C13—H13B109.5C8—N2—C7119.09 (12)
H13A—C13—H13B109.5C12—N2—C7119.38 (13)
C9—C13—H13C109.5
C6—C1—C2—C31.1 (4)C23—C18—C19—C20−0.3 (2)
N1—C1—C2—C3−178.1 (2)C17—C18—C19—C20178.78 (15)
C1—C2—C3—C4−0.9 (4)C18—C19—C20—C210.1 (2)
C2—C3—C4—C5−0.1 (3)C19—C20—C21—C24−179.44 (15)
C2—C3—C4—C7−179.1 (2)C19—C20—C21—C220.3 (2)
C3—C4—C5—C60.9 (3)C24—C21—C22—C23179.20 (16)
C7—C4—C5—C6179.83 (16)C20—C21—C22—C23−0.6 (3)
C2—C1—C6—C5−0.4 (3)C21—C22—C23—C180.4 (3)
N1—C1—C6—C5178.90 (15)C17—C18—C23—C22−179.01 (16)
C4—C5—C6—C1−0.7 (3)C19—C18—C23—C220.0 (3)
C5—C4—C7—N24.9 (2)C20—C21—C24—C254.2 (3)
C3—C4—C7—N2−176.16 (17)C22—C21—C24—C25−175.56 (16)
N2—C8—C9—C100.3 (2)C20—C21—C24—C26−177.65 (16)
N2—C8—C9—C13−179.80 (16)C22—C21—C24—C262.6 (3)
C8—C9—C10—C110.7 (2)C2—C1—N1—O1−6.9 (3)
C13—C9—C10—C11−179.16 (17)C6—C1—N1—O1173.77 (16)
C9—C10—C11—C12−1.0 (2)C2—C1—N1—O2171.89 (19)
C9—C10—C11—C14178.76 (15)C6—C1—N1—O2−7.4 (2)
C10—C11—C12—N20.2 (2)C9—C8—N2—C12−1.1 (2)
C14—C11—C12—N2−179.49 (14)C9—C8—N2—C7178.29 (13)
C16—C17—C18—C23179.39 (16)C11—C12—N2—C80.8 (2)
C15—C17—C18—C230.5 (3)C11—C12—N2—C7−178.60 (13)
C16—C17—C18—C190.4 (2)C4—C7—N2—C899.78 (16)
C15—C17—C18—C19−178.44 (16)C4—C7—N2—C12−80.84 (18)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C5—H5···N20.932.562.895 (2)102
C7—H7B···N4i0.972.433.245 (3)141
C8—H8···O2ii0.932.463.119 (2)128
Symmetry codes: (i) x−1, y−1, z; (ii) x, y+1, z.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C5—H5···N20.932.562.895 (2)102
C7—H7B···N4i0.972.433.245 (3)141
C8—H8···O2ii0.932.463.119 (2)128
Symmetry codes: (i) x−1, y−1, z; (ii) x, y+1, z.
Acknowledgements top

This work was supported by the National Natural Science Foundation of China (project Nos. 20371002 and 20771006) and the Natural Science Foundation of the Education Committee of Anhui Province, China (project No. KJ2008B004).

references
References top

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