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Acta Cryst. (2008). E64, o997    [ doi:10.1107/S1600536808012622 ]

4-[5-(4-Pyridyl)-1,3,4-oxadiazol-2-yl]pyridine N-oxide-isophthalic acid (1/1)

G.-G. Hou, L.-L. Liu, J.-P. Ma, R.-Q. Huang and Y.-B. Dong

Abstract top

The title compound, C12H8N4O2·C8H6O4, was synthesized from 4-[5-(4-pyridyl)-1,3,4-oxadiazol-2-yl]pyridine N-oxide and isophthalic acid. The two molecules are linked through O-H...O and O-H...N hydrogen bonds. Weak intramolecular [pi]-[pi] interactions between the two hydrogen-bonded chains result in the formation a one-dimensional supramolecular curved tape (the face-to-face distance between the pyridine N-oxide ring and the benzene ring is 3.7 Å).

Comment top

Rigid pyridyl compounds have been considered as good hydrogen bond acceptors. These compounds include 4,4-bipyridine (Lu et al., 1997; Kitagawa et al., 2004; Tan et al., 2006), 1,2-bis(4-pyridyl)ethyne (Beckmann & Jänicke, 2006), 4,4'-bipyridine-N,N'-dioxide (Long et al., 2004; Ma et al., 2005), and other similar molecules. We recently prepared the rigid bent compound, 2-(4-pyridyl)-5-(4-pyridyl N-oxide)-1,3,4-oxadiazole, (L2). It has a rigid 144° angle because of the bridging five-membered oxadiazole ring. In addition, isophthalic acid is a good hydrogen-bonding donor and its two carboxylic acid moieties make an angle of 120°. Supramolecular systems with novel architecture may result because of their specific geometry. Accordingly, when L2 reacted with isophthalic acid in a mixed CH2Cl2/CH3OH solution, yellow crystals formed and its structure is reported here.

The molecular structure of (1) is shown in Fig. 1. The asymmetric unit contains one L2 molecule and one isophthalic acid molecule. O···H—O and N···H—O hydrogen bonds (Fig. 3) are formed by the –COOH groups of the isophthalic acid and the pyridyl-N-oxide O atom and Npyridine atom, (Table 1). The dihedral angles between the benzene ring of isophthalic acid and pyridyl-N-oxide ring and pyridyl ring are 1.4° and 7.0°, respectively, which are similar to previously reported experimental values (Du et al., 2006; Tan et al., 2006). In addition to the specific geometry of the oxadiazole-containing rigid curved organic ligand L2, the molecules in (1) connect with each other generating one-dimensional extended zigzag chains, which have not been obtained using normal linear rigid bidentate organic ligands (Dong & Ma, 2003).

In the solid state, the crystal packing view of (1) shows a pair of zigzag chains which stack via aromatic π-π interactions (Fig. 3). The face-to-face distance between the pyridine-N-oxide ring and benzene ring from isophthalic acid is 3.7 Å. The shortest close contact is 3.447 (6) Å. Although these values are typical for aromatic π-π stacking interactions, compared with the strong π-π interactions (Hunter, 1994) they are comparatively weak. Two adjacent chains are further linked via intramolecular π-π stacking interactions to construct a one-dimensional supramolecular curved tape (Fig. 3). These weak intramolecular π-π interactions and crucial hydrogen bonds enhance the stability of the compound (1).

Related literature top

For related literature, see: Beckmann & Jänicke (2006); Dong et al. (2003); Du et al. (2006); Hunter (1994); Kitagawa et al. (2004); Long et al. (2004); Lu et al. (1997); Ma et al. (2005); Ren et al. (1995); Tan et al. (2006).

Experimental top

L1 (2,5-bis(4-pyridyl)-1,3,4-oxadiazole) was prepared according to literature methods (Ren et al., 1995). L1 (1.1 g, 5 mmol), 1.0 ml hydrogen dioxide 30% solution and 3.0 ml acetic acid were mixed and refluxed at 343–353 K for 20 h. After removal of solvent under vacuum, the residue was purified on a silica gel column using CH2Cl2/CH3OH (15:1, v/v) as the eluent to afford L2, Yield: 38%. Mp: 501–503 K. 1H NMR (DMSO, 300 MHz, p.p.m.): δ 8.89–8.91 (d, 2H, 2C5H4N), 8.34–8.37 (d, 2H, 2C5H4NO), 7.99–8.06 (m, 4H, 2C5H4N, 2C5H4NO). IR (KBr pellet cm-1): 3423(s), 1620(m), 1563(m), 1537(m), 1475(s), 1439(s), 1407(s), 1272(s), 1174(s), 1111(m), 965(m), 848(m), 740(m), 703(s), 644(s), 509(m).

A CH2Cl2 and CH3OH solution (10 ml, 1:1, v/v) of L2 (24 mg, 0.1 mmol) and isophthalic acid (16.6 mg, 0.1 mmol) kept at room temperature. After a few days yellow block crystals (1) were obtained (36 mg). Yield: 89%.

Refinement top

H atoms on O atoms were located in a difference Fourier map and refined as riding in their as-found relative positions, with Uiso(H) = 1.5Ueq(O). Other H atoms were placed in calculated positions, with C—H = 0.93 Å, and refined in riding mode, with Uiso(H) = 1.2Ueq(C) (aromatic).

Computing details top

Data collection: SMART (Bruker 2000); cell refinement: SMART (Bruker 2000); data reduction: SAINT (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 structure of (1), with 30% probability displacement ellipsoids (arbitrary spheres for H atoms).
[Figure 2] Fig. 2. : A view of the hydrogen-bonded chains observed in the crystal structure of (1).
[Figure 3] Fig. 3. : The crystal packing of (1) via weak π-π interactions, and the face-to-face distance is 3.7 Å.
[Figure 4] Fig. 4. The formation of L2.
4-[5-(4-pyridyl)-1,3,4-oxadiazol-2-yl]pyridine N-oxide–isophthalic acid (1/1) top
Crystal data top
C12H8N4O2·C8H6O4Z = 2
Mr = 406.35F000 = 420
Triclinic, P1Dx = 1.475 Mg m−3
Hall symbol: -P 1Mo Kα radiation
λ = 0.71073 Å
a = 7.0993 (18) ÅCell parameters from 893 reflections
b = 7.1770 (19) Åθ = 3.2–21.1º
c = 19.823 (5) ŵ = 0.11 mm−1
α = 93.003 (4)ºT = 298 (2) K
β = 98.481 (3)ºBar, colourless
γ = 112.745 (4)º0.30 × 0.15 × 0.06 mm
V = 914.6 (4) Å3
Data collection top
Bruker SMART APEX
diffractometer		1972 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.027
Monochromator: graphiteθmax = 25.0º
T = 298(2) Kθmin = 3.1º
φ and ω scansh = −8→8
Absorption correction: nonek = −8→8
4661 measured reflectionsl = −17→23
3189 independent reflections
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)] = 0.052H-atom parameters constrained
wR(F2) = 0.132  w = 1/[σ2(Fo2) + (0.0637P)2]
where P = (Fo2 + 2Fc2)/3
S = 0.98(Δ/σ)max = 0.001
3189 reflectionsΔρmax = 0.30 e Å−3
272 parametersΔρmin = −0.15 e Å−3
Primary atom site location: structure-invariant direct methodsExtinction correction: none
Crystal data top
C12H8N4O2·C8H6O4γ = 112.745 (4)º
Mr = 406.35V = 914.6 (4) Å3
Triclinic, P1Z = 2
a = 7.0993 (18) ÅMo Kα
b = 7.1770 (19) ŵ = 0.11 mm−1
c = 19.823 (5) ÅT = 298 (2) K
α = 93.003 (4)º0.30 × 0.15 × 0.06 mm
β = 98.481 (3)º
Data collection top
Bruker SMART APEX
diffractometer		3189 independent reflections
Absorption correction: none1972 reflections with I > 2σ(I)
4661 measured reflectionsRint = 0.027
Refinement top
R[F2 > 2σ(F2)] = 0.052272 parameters
wR(F2) = 0.132H-atom parameters constrained
S = 0.98Δρmax = 0.30 e Å−3
3189 reflectionsΔρmin = −0.15 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
O10.7708 (3)0.9021 (3)0.64281 (9)0.0693 (6)
O21.0221 (3)0.8709 (4)0.59557 (10)0.0861 (7)
O5−0.2941 (3)0.2221 (4)−0.02763 (9)0.0882 (8)
O30.8643 (3)1.0843 (3)0.88695 (9)0.0738 (6)
H30.83091.12760.92030.111*
O41.1774 (3)1.2181 (3)0.95238 (9)0.0726 (6)
C1−0.4071 (4)0.2792 (4)0.06980 (13)0.0592 (8)
H1A−0.54080.23740.04460.071*
C2−0.3697 (4)0.3405 (4)0.13821 (12)0.0528 (7)
H2−0.47810.33990.15950.063*
C3−0.1721 (4)0.4035 (4)0.17649 (11)0.0427 (6)
C4−0.0155 (4)0.4016 (4)0.14322 (12)0.0515 (7)
H40.11890.44290.16780.062*
C5−0.0572 (4)0.3385 (4)0.07365 (12)0.0558 (7)
H5A0.04890.33750.05130.067*
C6−0.1345 (4)0.4706 (4)0.24973 (12)0.0436 (6)
C70.0337 (4)0.5784 (4)0.35129 (11)0.0431 (6)
C80.2083 (4)0.6463 (4)0.40831 (11)0.0415 (6)
C90.1803 (4)0.7064 (4)0.47216 (12)0.0496 (7)
H90.05330.70760.47820.059*
C100.3421 (4)0.7639 (4)0.52633 (12)0.0520 (7)
H100.32050.80000.56940.062*
C110.5555 (4)0.7154 (4)0.45907 (13)0.0551 (7)
H110.68560.72050.45420.066*
C120.4001 (4)0.6505 (4)0.40169 (12)0.0490 (7)
H120.42450.61050.35960.059*
C130.9602 (4)0.9161 (4)0.64414 (14)0.0521 (7)
C141.0945 (4)0.9948 (4)0.71368 (11)0.0453 (6)
C151.0149 (4)1.0271 (4)0.77116 (12)0.0451 (6)
H150.87380.99750.76700.054*
C161.1455 (4)1.1037 (4)0.83507 (11)0.0436 (6)
C171.3553 (4)1.1470 (4)0.84013 (13)0.0533 (7)
H171.44431.19950.88220.064*
C181.4324 (4)1.1130 (4)0.78334 (13)0.0577 (8)
H181.57341.14190.78740.069*
C191.3043 (4)1.0369 (4)0.72065 (13)0.0542 (7)
H191.35861.01340.68270.065*
C201.0666 (4)1.1418 (4)0.89757 (13)0.0509 (7)
N1−0.2515 (3)0.2788 (3)0.03830 (10)0.0569 (6)
N2−0.2670 (3)0.4826 (3)0.28576 (10)0.0511 (6)
N3−0.1552 (3)0.5550 (3)0.35274 (10)0.0529 (6)
N40.5295 (3)0.7709 (3)0.52071 (10)0.0525 (6)
H10.70160.85260.60430.079*
O60.0597 (2)0.5275 (2)0.28698 (7)0.0451 (5)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0608 (14)0.0982 (17)0.0411 (11)0.0313 (12)−0.0073 (9)−0.0095 (10)
O20.0854 (16)0.128 (2)0.0449 (12)0.0492 (15)0.0062 (11)−0.0239 (12)
O50.0759 (15)0.157 (2)0.0339 (12)0.0592 (15)−0.0082 (10)−0.0223 (12)
O30.0545 (13)0.1118 (18)0.0450 (12)0.0277 (12)0.0025 (9)−0.0144 (11)
O40.0630 (13)0.1144 (18)0.0341 (11)0.0374 (12)−0.0070 (9)−0.0135 (11)
C10.0494 (17)0.077 (2)0.0459 (17)0.0259 (15)−0.0048 (13)−0.0079 (14)
C20.0514 (17)0.0658 (19)0.0379 (16)0.0239 (14)0.0000 (12)−0.0024 (13)
C30.0490 (16)0.0424 (16)0.0352 (14)0.0190 (12)0.0020 (12)0.0006 (11)
C40.0498 (17)0.0596 (19)0.0377 (16)0.0182 (14)−0.0013 (12)−0.0006 (12)
C50.0523 (18)0.075 (2)0.0405 (16)0.0282 (15)0.0051 (13)0.0002 (14)
C60.0501 (17)0.0421 (16)0.0331 (14)0.0167 (13)−0.0027 (12)0.0002 (11)
C70.0534 (17)0.0443 (16)0.0326 (15)0.0210 (13)0.0079 (12)0.0010 (11)
C80.0474 (16)0.0436 (16)0.0313 (14)0.0182 (12)0.0019 (11)0.0009 (11)
C90.0487 (16)0.0590 (18)0.0375 (15)0.0193 (14)0.0060 (12)−0.0018 (12)
C100.0591 (19)0.0614 (19)0.0319 (15)0.0225 (15)0.0052 (13)−0.0025 (12)
C110.0491 (17)0.066 (2)0.0508 (18)0.0258 (15)0.0033 (14)0.0032 (14)
C120.0551 (18)0.0575 (18)0.0338 (15)0.0228 (14)0.0073 (13)−0.0006 (12)
C130.0625 (19)0.0471 (18)0.0468 (18)0.0236 (14)0.0068 (14)0.0024 (13)
C140.0574 (17)0.0467 (17)0.0315 (14)0.0233 (13)0.0020 (12)−0.0004 (11)
C150.0472 (15)0.0468 (16)0.0417 (15)0.0221 (13)0.0003 (12)0.0039 (12)
C160.0492 (16)0.0482 (16)0.0329 (14)0.0220 (13)−0.0005 (12)0.0029 (11)
C170.0537 (18)0.0604 (19)0.0428 (16)0.0251 (15)−0.0042 (13)−0.0001 (13)
C180.0508 (17)0.073 (2)0.0485 (18)0.0270 (16)0.0037 (14)0.0004 (15)
C190.0609 (19)0.0605 (19)0.0458 (17)0.0285 (15)0.0126 (14)0.0029 (13)
C200.0509 (18)0.0600 (19)0.0408 (16)0.0251 (14)−0.0007 (13)0.0014 (13)
N10.0585 (16)0.0779 (18)0.0301 (13)0.0295 (13)−0.0054 (11)−0.0088 (11)
N20.0505 (14)0.0635 (16)0.0366 (13)0.0230 (12)0.0021 (10)−0.0024 (10)
N30.0525 (15)0.0684 (16)0.0351 (13)0.0244 (12)0.0016 (10)−0.0013 (10)
N40.0582 (15)0.0540 (15)0.0382 (13)0.0189 (12)−0.0012 (11)0.0011 (10)
O60.0486 (11)0.0548 (11)0.0293 (9)0.0211 (9)0.0009 (8)−0.0035 (7)
Geometric parameters (Å, °) top
O1—C131.306 (3)C8—C121.377 (3)
O1—H10.8221C8—C91.382 (3)
O2—C131.195 (3)C9—C101.366 (3)
O5—N11.303 (2)C9—H90.9300
O3—C201.312 (3)C10—N41.333 (3)
O3—H30.8200C10—H100.9300
O4—C201.205 (3)C11—N41.326 (3)
C1—N11.347 (3)C11—C121.380 (3)
C1—C21.358 (3)C11—H110.9300
C1—H1A0.9300C12—H120.9300
C2—C31.381 (3)C13—C141.497 (3)
C2—H20.9300C14—C191.384 (3)
C3—C41.378 (3)C14—C151.391 (3)
C3—C61.457 (3)C15—C161.398 (3)
C4—C51.380 (3)C15—H150.9300
C4—H40.9300C16—C171.385 (3)
C5—N11.343 (3)C16—C201.487 (3)
C5—H5A0.9300C17—C181.372 (3)
C6—N21.287 (3)C17—H170.9300
C6—O61.358 (3)C18—C191.372 (3)
C7—N31.290 (3)C18—H180.9300
C7—O61.366 (3)C19—H190.9300
C7—C81.454 (3)N2—N31.400 (3)
C13—O1—H1109.3C8—C12—C11118.4 (2)
C20—O3—H3109.5C8—C12—H12120.8
N1—C1—C2120.3 (2)C11—C12—H12120.8
N1—C1—H1A119.8O2—C13—O1124.3 (3)
C2—C1—H1A119.8O2—C13—C14122.8 (3)
C1—C2—C3120.7 (2)O1—C13—C14112.8 (2)
C1—C2—H2119.7C19—C14—C15119.2 (2)
C3—C2—H2119.7C19—C14—C13118.7 (2)
C4—C3—C2118.0 (2)C15—C14—C13122.0 (2)
C4—C3—C6122.1 (2)C14—C15—C16120.4 (2)
C2—C3—C6119.9 (2)C14—C15—H15119.8
C3—C4—C5120.3 (2)C16—C15—H15119.8
C3—C4—H4119.8C17—C16—C15118.9 (2)
C5—C4—H4119.8C17—C16—C20119.1 (2)
N1—C5—C4119.7 (2)C15—C16—C20122.0 (2)
N1—C5—H5A120.1C18—C17—C16120.3 (2)
C4—C5—H5A120.1C18—C17—H17119.8
N2—C6—O6113.3 (2)C16—C17—H17119.8
N2—C6—C3127.5 (2)C19—C18—C17120.8 (3)
O6—C6—C3119.1 (2)C19—C18—H18119.6
N3—C7—O6112.1 (2)C17—C18—H18119.6
N3—C7—C8127.9 (2)C18—C19—C14120.2 (2)
O6—C7—C8120.0 (2)C18—C19—H19119.9
C12—C8—C9118.4 (2)C14—C19—H19119.9
C12—C8—C7122.7 (2)O4—C20—O3123.4 (2)
C9—C8—C7118.8 (2)O4—C20—C16123.4 (2)
C10—C9—C8119.0 (2)O3—C20—C16113.2 (2)
C10—C9—H9120.5O5—N1—C5120.9 (2)
C8—C9—H9120.5O5—N1—C1118.2 (2)
N4—C10—C9123.4 (2)C5—N1—C1120.9 (2)
N4—C10—H10118.3C6—N2—N3105.6 (2)
C9—C10—H10118.3C7—N3—N2106.81 (19)
N4—C11—C12123.7 (2)C11—N4—C10117.1 (2)
N4—C11—H11118.2C6—O6—C7102.14 (18)
C12—C11—H11118.2
N1—C1—C2—C30.2 (4)C14—C15—C16—C20179.5 (2)
C1—C2—C3—C4−0.2 (4)C15—C16—C17—C18−0.7 (4)
C1—C2—C3—C6179.4 (2)C20—C16—C17—C18179.9 (2)
C2—C3—C4—C50.1 (4)C16—C17—C18—C190.4 (4)
C6—C3—C4—C5−179.5 (2)C17—C18—C19—C140.6 (4)
C3—C4—C5—N10.0 (4)C15—C14—C19—C18−1.2 (4)
C4—C3—C6—N2178.5 (3)C13—C14—C19—C18178.7 (2)
C2—C3—C6—N2−1.1 (4)C17—C16—C20—O43.7 (4)
C4—C3—C6—O6−2.0 (4)C15—C16—C20—O4−175.7 (3)
C2—C3—C6—O6178.4 (2)C17—C16—C20—O3−176.5 (2)
N3—C7—C8—C12174.8 (2)C15—C16—C20—O34.1 (4)
O6—C7—C8—C12−4.2 (4)C4—C5—N1—O5178.7 (2)
N3—C7—C8—C9−4.2 (4)C4—C5—N1—C10.0 (4)
O6—C7—C8—C9176.9 (2)C2—C1—N1—O5−178.8 (2)
C12—C8—C9—C10−1.1 (4)C2—C1—N1—C50.0 (4)
C7—C8—C9—C10177.9 (2)O6—C6—N2—N30.5 (3)
C8—C9—C10—N42.0 (4)C3—C6—N2—N3−179.9 (2)
C9—C8—C12—C11−0.3 (4)O6—C7—N3—N20.4 (3)
C7—C8—C12—C11−179.3 (2)C8—C7—N3—N2−178.6 (2)
N4—C11—C12—C81.2 (4)C6—N2—N3—C7−0.5 (3)
O2—C13—C14—C196.8 (4)C12—C11—N4—C10−0.5 (4)
O1—C13—C14—C19−173.4 (2)C9—C10—N4—C11−1.1 (4)
O2—C13—C14—C15−173.3 (3)N2—C6—O6—C7−0.3 (3)
O1—C13—C14—C156.5 (4)C3—C6—O6—C7−179.9 (2)
C19—C14—C15—C160.9 (4)N3—C7—O6—C60.0 (3)
C13—C14—C15—C16−179.0 (2)C8—C7—O6—C6179.0 (2)
C14—C15—C16—C170.1 (4)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O1—H1···N40.821.822.640 (2)171
O3—H3···O5i0.821.722.521 (3)163
Symmetry codes: (i) x+1, y+1, z+1.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O1—H1···N40.821.822.640 (2)171
O3—H3···O5i0.821.722.521 (3)163
Symmetry codes: (i) x+1, y+1, z+1.
Acknowledgements top

The authors thank the National Natural Science Foundation of China (Nos. 20671060) and Shangdong Natural Science Foundation (Nos. J06D05 and 2006BS04040) for support.

references
References top

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