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Acta Crystallogr Sect E Struct Rep Online. 2010 May 1; 66(Pt 5): o1173.
Published online 2010 April 24. doi:  10.1107/S1600536810014698
PMCID: PMC2979186

4-(4-Nitro­benz­yl)pyridinium 5-nitro­salicylate

Abstract

In the title salt, C12H11N2O2 +·C7H4NO5 , the cations and anions inter­act through asymmetric cyclic pyridinium–carboxyl­ate N—H(...)O,O′ hydrogen-bonding associations [graph set R 1 2(4)], giving discrete heterodimers having weak cation–anion π–π aromatic ring inter­actions [minimum ring centroid separation = 3.7116 (9) Å].

Related literature

For structural data on nitro-substituted 4-benzyl­pyridines and related compounds, see Seff & Trueblood (1968 [triangle]); Ottersen & Seff (1974 [triangle]); Scherl et al. (1996 [triangle]); Smith et al. (1997 [triangle]); Naumov et al. (2002 [triangle]). For structures of Lewis base salts of 5-nitro­salicylic acid, see: Smith et al. (1996 [triangle], 2005 [triangle], 2006 [triangle]). For graph-set motifs, see: Etter et al. (1990 [triangle]).

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Object name is e-66-o1173-scheme1.jpg

Experimental

Crystal data

  • C12H11N2O2 +·C7H4NO5
  • M r = 397.34
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o1173-efi1.jpg
  • a = 8.3287 (5) Å
  • b = 10.8219 (7) Å
  • c = 11.3896 (8) Å
  • α = 65.160 (6)°
  • β = 88.286 (5)°
  • γ = 70.553 (6)°
  • V = 871.17 (12) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 0.12 mm−1
  • T = 200 K
  • 0.25 × 0.25 × 0.20 mm

Data collection

  • Oxford Diffraction Gemini-S CCD-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996 [triangle]) T min = 0.795, T max = 0.900
  • 10797 measured reflections
  • 3419 independent reflections
  • 2615 reflections with I > 2σ(I)
  • R int = 0.021

Refinement

  • R[F 2 > 2σ(F 2)] = 0.034
  • wR(F 2) = 0.091
  • S = 1.03
  • 3419 reflections
  • 270 parameters
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.15 e Å−3
  • Δρmin = −0.19 e Å−3

Data collection: CrysAlis PRO (Oxford Diffraction, 2009 [triangle]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]) within WinGX (Farrugia, 1999 [triangle]); molecular graphics: PLATON (Spek, 2009 [triangle]); software used to prepare material for publication: PLATON.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810014698/pv2273sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810014698/pv2273Isup2.hkl

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

Acknowledgments

The authors acknowledge financial support from the Australian Research Council and the Faculty of Science and Technology, Queensland University of Technology.

supplementary crystallographic information

Comment

The Lewis base 4-(4-nitrobenzyl)pyridine (NBP) is an analogue of 2-(2,4-dinitrobenzyl)pyridine (DNBP) which is significant because of its unusual photochromic behaviour in the solid state, although NBP does not possess such properties. The structure of DNBP has been determined (Seff & Trueblood, 1968; Scherl et al., 1996; Naumov et al., 2002), as well that of its isomer 4-(2,4-dinitrobenzyl)pyridine (Ottersen & Seff (1974), but the structure of NBP itself is not known. A structure of a cocrystal adduct of NBP with 4-aminobenzoic acid has been reported (Smith et al., 1997).

Our reaction of NBP with 5-nitrosalicylic acid (5-NSA) gave the title compound C12H11N2O2+ C7H4NO5- (I), the structure of which is reported here. The acid 5-NSA has proved useful for formation of crystalline salts with a number of Lewis bases (Smith et al., 1996; Smith et al., 2005; Smith et al., 2006). With the title compound (I) (Fig. 1), the NBP cations and 5-NSA anions interact through asymmetric cyclic N+–H···O,O'carboxyl hydrogen-bonding associations (Table 1), giving discrete heterodimers [graph set R21(4) (Etter et al., 1990)]. There are weak cation–anion π–π aromatic ring interactions present in the crystal packing [minimum ring centroid separation between rings N1–C6 and C1A–C6A, 3.7166 (9) Å] (Fig. 2). With the NBP cation the two rings are approximately normal to each other [torsion angle C3–C4–C42–C11, -77.72 (17)°] with the nitro group close to coplanar with the benzene ring [torsion angle C31–C41–N41–O42, 170.27 (13)°]. The usual intramolecular phenolO—H···Ocarboxyl hydrogen bond [2.4623 (17) Å] is present in the 5-NSA anion which, including the nitro group is close to planar [torsion angles C2A–C1A–C11A–O11A, -173.72 (13)°; C4A–C5A–N5A–O52A, 177.68 (13)°].

Experimental

The title compound was synthesized by heating together under reflux for 10 minutes, 1 mmol quantities of 4-(4-nitrobenzyl)pyridine with 5-nitrosalicylic acid in 50 ml of 50% ethanol–water. After concentration to ca. 30 ml, partial room temperature evaporation of the hot-filtered solution gave yellow crystal aggregates (m.p. 416–417 K) from which a block section was cleaved for the X-ray analysis.

Refinement

Hydrogen atoms involved in hydrogen-bonding interactions were located by difference methods and their positional and isotropic displacement parameters were refined. The other H-atoms were included in the refinement at calculated positions [C–H = 0.93 Å (aromatic) and 0.97 Å (aliphatic) and Uiso(H) = 1.2Ueq(C)], using a riding-model approximation.

Figures

Fig. 1.
Molecular configuration and atom naming scheme for the hydrogen-bonded NBP cation and 5-NSA anion species in (I). Hydrogen bonds are shown as dashed lines and displacement ellipsoids are drawn at the 50% probability level.
Fig. 2.
The packing of (I) in the unit cell viewed down the a axis showing partial overlap of cation and anion aromatic rings. Non-associative H atoms are omitted. For symmetry code (i) -x + 1, -y + 1, -z + 2.

Crystal data

C12H11N2O2+·C7H4NO5Z = 2
Mr = 397.34F(000) = 412
Triclinic, P1Dx = 1.515 Mg m3
Hall symbol: -P 1Melting point = 416–417 K
a = 8.3287 (5) ÅMo Kα radiation, λ = 0.71073 Å
b = 10.8219 (7) ÅCell parameters from 5316 reflections
c = 11.3896 (8) Åθ = 3.5–27.3°
α = 65.160 (6)°µ = 0.12 mm1
β = 88.286 (5)°T = 200 K
γ = 70.553 (6)°Block, yellow
V = 871.17 (12) Å30.25 × 0.25 × 0.20 mm

Data collection

Oxford Diffraction Gemini-S CCD-detector diffractometer3419 independent reflections
Radiation source: Enhance (Mo) X-ray source2615 reflections with I > 2σ(I)
graphiteRint = 0.021
ω scansθmax = 26.0°, θmin = 3.5°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)h = −10→10
Tmin = 0.795, Tmax = 0.900k = −13→13
10797 measured reflectionsl = −14→14

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.034Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.091H atoms treated by a mixture of independent and constrained refinement
S = 1.03w = 1/[σ2(Fo2) + (0.0545P)2] where P = (Fo2 + 2Fc2)/3
3419 reflections(Δ/σ)max = 0.001
270 parametersΔρmax = 0.15 e Å3
0 restraintsΔρmin = −0.19 e Å3

Special details

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell esds are taken into account in the estimation of distances, angles and torsion angles
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)

xyzUiso*/Ueq
O410.59084 (14)0.14581 (11)0.23776 (10)0.0489 (4)
O420.42667 (14)0.05808 (12)0.17918 (10)0.0510 (4)
N10.16696 (14)0.34798 (12)0.86559 (10)0.0324 (4)
N410.46108 (16)0.11510 (12)0.24364 (11)0.0383 (4)
C20.23613 (17)0.20902 (15)0.88611 (13)0.0337 (4)
C30.18362 (17)0.16091 (14)0.80647 (12)0.0320 (4)
C40.05789 (16)0.25761 (14)0.70081 (12)0.0289 (4)
C5−0.01214 (17)0.40136 (14)0.68153 (13)0.0316 (4)
C60.04413 (18)0.44346 (15)0.76571 (13)0.0346 (4)
C110.12505 (16)0.18753 (13)0.51267 (12)0.0283 (4)
C210.28151 (17)0.20737 (14)0.51098 (12)0.0308 (4)
C310.39116 (17)0.18636 (14)0.42196 (12)0.0319 (4)
C410.34282 (17)0.14340 (13)0.33503 (12)0.0308 (4)
C420.00262 (17)0.20617 (16)0.61020 (13)0.0363 (5)
C510.18791 (18)0.12374 (14)0.33259 (13)0.0360 (4)
C610.07906 (17)0.14782 (14)0.42063 (13)0.0342 (4)
O2A0.08063 (12)0.85096 (11)0.92983 (10)0.0424 (3)
O11A0.28861 (12)0.41609 (10)1.02623 (9)0.0375 (3)
O12A0.11745 (14)0.63753 (11)0.88914 (10)0.0477 (4)
O51A0.63063 (13)0.55882 (12)1.41523 (10)0.0484 (4)
O52A0.65275 (13)0.37091 (12)1.38388 (11)0.0512 (4)
N5A0.58706 (15)0.50136 (14)1.35463 (11)0.0362 (4)
C1A0.28307 (16)0.61579 (14)1.06572 (12)0.0282 (4)
C2A0.20276 (17)0.76553 (14)1.03229 (13)0.0318 (4)
C3A0.24883 (18)0.82552 (15)1.10787 (13)0.0363 (4)
C4A0.37383 (17)0.73914 (15)1.21296 (13)0.0346 (5)
C5A0.45327 (16)0.59222 (14)1.24384 (12)0.0303 (4)
C6A0.40963 (16)0.53007 (14)1.17166 (12)0.0279 (4)
C11A0.22703 (17)0.55144 (15)0.98847 (13)0.0316 (4)
H10.213 (2)0.3733 (19)0.9259 (18)0.074 (6)*
H20.321600.144000.955900.0400*
H30.231900.063500.822900.0380*
H5−0.096900.468900.611800.0380*
H6−0.003800.539700.753100.0420*
H210.313300.235300.570900.0370*
H310.495200.200900.420900.0380*
H510.157500.094900.272900.0430*
H61−0.027100.137400.418500.0410*
H421−0.108700.275400.562600.0440*
H422−0.011300.113700.662200.0440*
H2A0.078 (3)0.773 (2)0.9050 (19)0.091 (7)*
H3A0.194600.923801.086700.0440*
H4A0.405300.778401.263200.0420*
H6A0.464800.431601.194000.0340*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O410.0475 (7)0.0522 (7)0.0479 (7)−0.0139 (5)0.0127 (5)−0.0259 (5)
O420.0613 (7)0.0543 (7)0.0382 (6)−0.0051 (5)−0.0024 (5)−0.0320 (5)
N10.0377 (6)0.0375 (7)0.0289 (6)−0.0167 (5)0.0056 (5)−0.0181 (5)
N410.0443 (7)0.0313 (6)0.0287 (6)−0.0011 (6)−0.0020 (5)−0.0124 (5)
C20.0347 (7)0.0353 (8)0.0267 (7)−0.0090 (6)−0.0010 (6)−0.0118 (6)
C30.0368 (8)0.0297 (7)0.0299 (7)−0.0101 (6)0.0025 (6)−0.0145 (6)
C40.0295 (7)0.0364 (7)0.0256 (7)−0.0153 (6)0.0062 (5)−0.0153 (6)
C50.0303 (7)0.0326 (7)0.0279 (7)−0.0082 (6)0.0009 (5)−0.0115 (6)
C60.0394 (8)0.0304 (7)0.0346 (8)−0.0123 (6)0.0076 (6)−0.0149 (6)
C110.0344 (7)0.0232 (7)0.0253 (7)−0.0088 (6)−0.0029 (5)−0.0093 (5)
C210.0395 (8)0.0313 (7)0.0274 (7)−0.0154 (6)0.0006 (6)−0.0155 (6)
C310.0362 (7)0.0320 (7)0.0292 (7)−0.0137 (6)0.0011 (6)−0.0134 (6)
C410.0375 (7)0.0241 (7)0.0245 (7)−0.0033 (6)−0.0016 (6)−0.0103 (5)
C420.0364 (8)0.0465 (9)0.0350 (8)−0.0190 (7)0.0028 (6)−0.0226 (7)
C510.0428 (8)0.0354 (8)0.0318 (7)−0.0081 (6)−0.0080 (6)−0.0199 (6)
C610.0343 (8)0.0350 (7)0.0352 (7)−0.0115 (6)−0.0047 (6)−0.0171 (6)
O2A0.0421 (6)0.0345 (6)0.0410 (6)−0.0050 (5)−0.0063 (5)−0.0134 (5)
O11A0.0435 (6)0.0341 (6)0.0381 (6)−0.0102 (4)−0.0051 (4)−0.0205 (5)
O12A0.0556 (7)0.0421 (6)0.0397 (6)−0.0083 (5)−0.0168 (5)−0.0181 (5)
O51A0.0545 (7)0.0607 (7)0.0454 (6)−0.0312 (6)−0.0048 (5)−0.0280 (5)
O52A0.0475 (6)0.0438 (6)0.0574 (7)−0.0075 (5)−0.0177 (5)−0.0226 (6)
N5A0.0347 (6)0.0464 (8)0.0363 (7)−0.0208 (6)0.0015 (5)−0.0210 (6)
C1A0.0273 (7)0.0331 (7)0.0287 (7)−0.0131 (6)0.0066 (5)−0.0160 (6)
C2A0.0299 (7)0.0330 (7)0.0321 (7)−0.0115 (6)0.0056 (6)−0.0136 (6)
C3A0.0403 (8)0.0310 (7)0.0426 (8)−0.0146 (6)0.0090 (6)−0.0193 (7)
C4A0.0385 (8)0.0409 (8)0.0385 (8)−0.0217 (7)0.0100 (6)−0.0245 (7)
C5A0.0272 (7)0.0379 (8)0.0314 (7)−0.0153 (6)0.0041 (5)−0.0174 (6)
C6A0.0271 (7)0.0307 (7)0.0296 (7)−0.0122 (6)0.0042 (5)−0.0149 (6)
C11A0.0317 (7)0.0382 (8)0.0286 (7)−0.0131 (6)0.0040 (6)−0.0173 (6)

Geometric parameters (Å, °)

O41—N411.2244 (19)C41—C511.379 (2)
O42—N411.2300 (18)C51—C611.380 (2)
O2A—C2A1.3378 (18)C2—H20.9300
O11A—C11A1.256 (2)C3—H30.9300
O12A—C11A1.2613 (18)C5—H50.9300
O51A—N5A1.2331 (19)C6—H60.9300
O52A—N5A1.227 (2)C21—H210.9300
O2A—H2A1.00 (2)C31—H310.9300
N1—C61.3366 (18)C42—H4210.9700
N1—C21.336 (2)C42—H4220.9700
N41—C411.4673 (19)C51—H510.9300
N1—H10.97 (2)C61—H610.9300
N5A—C5A1.4536 (18)C1A—C6A1.3828 (19)
C2—C31.363 (2)C1A—C11A1.494 (2)
C3—C41.3884 (19)C1A—C2A1.412 (2)
C4—C421.506 (2)C2A—C3A1.402 (2)
C4—C51.387 (2)C3A—C4A1.370 (2)
C5—C61.372 (2)C4A—C5A1.390 (2)
C11—C611.394 (2)C5A—C6A1.380 (2)
C11—C211.388 (2)C3A—H3A0.9300
C11—C421.516 (2)C4A—H4A0.9300
C21—C311.383 (2)C6A—H6A0.9300
C31—C411.376 (2)
C2A—O2A—H2A97.0 (12)C5—C6—H6120.00
C2—N1—C6120.47 (13)C11—C21—H21119.00
O41—N41—C41118.56 (12)C31—C21—H21119.00
O42—N41—C41118.07 (13)C41—C31—H31121.00
O41—N41—O42123.34 (13)C21—C31—H31121.00
C6—N1—H1123.7 (12)C4—C42—H421109.00
C2—N1—H1115.8 (12)C4—C42—H422109.00
O52A—N5A—C5A118.88 (13)C11—C42—H421109.00
O51A—N5A—O52A122.56 (13)C11—C42—H422109.00
O51A—N5A—C5A118.56 (14)H421—C42—H422108.00
N1—C2—C3121.14 (13)C61—C51—H51121.00
C2—C3—C4119.88 (14)C41—C51—H51121.00
C3—C4—C5117.93 (13)C11—C61—H61119.00
C5—C4—C42121.87 (12)C51—C61—H61119.00
C3—C4—C42120.20 (14)C2A—C1A—C11A119.62 (12)
C4—C5—C6119.72 (13)C6A—C1A—C11A120.95 (14)
N1—C6—C5120.84 (15)C2A—C1A—C6A119.41 (13)
C21—C11—C61118.29 (13)O2A—C2A—C1A120.58 (13)
C42—C11—C61118.58 (13)O2A—C2A—C3A119.38 (14)
C21—C11—C42123.13 (12)C1A—C2A—C3A120.04 (13)
C11—C21—C31121.31 (13)C2A—C3A—C4A119.91 (15)
C21—C31—C41118.51 (14)C3A—C4A—C5A119.44 (14)
N41—C41—C31119.00 (13)N5A—C5A—C6A118.90 (14)
C31—C41—C51122.04 (13)C4A—C5A—C6A121.88 (13)
N41—C41—C51118.94 (12)N5A—C5A—C4A119.22 (13)
C4—C42—C11114.93 (12)C1A—C6A—C5A119.31 (14)
C41—C51—C61118.52 (13)O11A—C11A—C1A118.90 (12)
C11—C61—C51121.28 (14)O12A—C11A—C1A117.35 (14)
N1—C2—H2119.00O11A—C11A—O12A123.74 (14)
C3—C2—H2119.00C2A—C3A—H3A120.00
C4—C3—H3120.00C4A—C3A—H3A120.00
C2—C3—H3120.00C3A—C4A—H4A120.00
C4—C5—H5120.00C5A—C4A—H4A120.00
C6—C5—H5120.00C1A—C6A—H6A120.00
N1—C6—H6120.00C5A—C6A—H6A120.00
C6—N1—C2—C3−0.1 (2)C11—C21—C31—C41−0.7 (2)
C2—N1—C6—C5−0.7 (2)C21—C31—C41—N41−177.57 (13)
O41—N41—C41—C31−7.89 (19)C21—C31—C41—C511.3 (2)
O41—N41—C41—C51173.20 (13)C31—C41—C51—C61−0.2 (2)
O42—N41—C41—C31170.27 (13)N41—C41—C51—C61178.73 (13)
O42—N41—C41—C51−8.65 (19)C41—C51—C61—C11−1.6 (2)
O52A—N5A—C5A—C4A177.68 (13)C6A—C1A—C2A—O2A179.64 (13)
O52A—N5A—C5A—C6A−2.8 (2)C6A—C1A—C2A—C3A−1.4 (2)
O51A—N5A—C5A—C4A−2.7 (2)C11A—C1A—C2A—O2A−2.0 (2)
O51A—N5A—C5A—C6A176.89 (13)C11A—C1A—C2A—C3A177.02 (13)
N1—C2—C3—C41.0 (2)C2A—C1A—C6A—C5A0.9 (2)
C2—C3—C4—C42178.32 (13)C11A—C1A—C6A—C5A−177.44 (13)
C2—C3—C4—C5−1.0 (2)C2A—C1A—C11A—O11A−173.72 (13)
C3—C4—C5—C60.2 (2)C2A—C1A—C11A—O12A5.3 (2)
C42—C4—C5—C6−179.08 (13)C6A—C1A—C11A—O11A4.6 (2)
C3—C4—C42—C11−77.72 (17)C6A—C1A—C11A—O12A−176.38 (13)
C5—C4—C42—C11101.54 (17)O2A—C2A—C3A—C4A−179.94 (14)
C4—C5—C6—N10.6 (2)C1A—C2A—C3A—C4A1.1 (2)
C61—C11—C21—C31−1.0 (2)C2A—C3A—C4A—C5A−0.3 (2)
C21—C11—C42—C43.8 (2)C3A—C4A—C5A—N5A179.37 (13)
C61—C11—C42—C4−176.59 (13)C3A—C4A—C5A—C6A−0.2 (2)
C21—C11—C61—C512.2 (2)N5A—C5A—C6A—C1A−179.70 (12)
C42—C11—C21—C31178.66 (14)C4A—C5A—C6A—C1A−0.2 (2)
C42—C11—C61—C51−177.47 (14)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N1—H1···O11A0.97 (2)1.612 (19)2.5804 (16)180 (2)
N1—H1···O12A0.97 (2)2.55 (2)3.1464 (18)120.2 (14)
O2A—H2A···O12A1.00 (2)1.48 (2)2.4623 (17)165 (2)
C2—H2···O42i0.932.393.2153 (17)148
C6—H6···O12A0.932.593.185 (2)122
C21—H21···O51Aii0.932.493.271 (2)142
C31—H31···O52Aiii0.932.493.322 (2)149
C42—H421···O52Aiv0.972.503.3828 (19)151

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: PV2273).

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