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Acta Crystallogr Sect E Struct Rep Online. 2008 January 1; 64(Pt 1): o242.
Published online 2007 December 12. doi:  10.1107/S1600536807065245
PMCID: PMC2915300

N-Phenyl-N-{4-[5-(4-pyrid­yl)-1,3,4-oxadiazol-2-yl]phen­yl}aniline

Abstract

The title compound, C25H18N4O, is a non-planar bipolar ligand containing triphenyl­amine and 1,3,4-oxadiazole units. In the mol­ecule, the benzene ring, the 1,3,4-oxadiazole ring, and the pyridine ring are twisted slightly with respect to each other [dihedral angle between the benzene and 1,3,4-oxadiazole rings = 9.4 (4) and between the 1,3,4-oxadiazole and pyridine rings = 3.0 (4)°]. Moreover, the dihedral angles between the two phenyl rings and the benzene ring are 88.2 (4) and 113.3 (4)°, and that between the two phenyl rings is 67.9 (4)°. The closest distances between the pyridine ring and the 1,3,4-oxadiazole and benzene rings in adjacent mol­ecules are 3.316 and 3.363 Å, respectively, indicating the existence of π–π inter­actions.

Related literature

For related literature, see: Tang et al. (1987 [triangle]); Yeh et al. (2005 [triangle]); Xiang et al. (2006 [triangle]); Chan et al. (1999 [triangle]); Gong et al. (1998 [triangle]); Tamoto et al. (1997 [triangle]).

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Object name is e-64-0o242-scheme1.jpg

Experimental

Crystal data

  • C25H18N4O
  • M r = 390.43
  • Orthorhombic, An external file that holds a picture, illustration, etc.
Object name is e-64-0o242-efi1.jpg
  • a = 10.7125 (9) Å
  • b = 14.1797 (12) Å
  • c = 12.7835 (11) Å
  • V = 1941.8 (3) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.08 mm−1
  • T = 291 (2) K
  • 0.40 × 0.30 × 0.25 mm

Data collection

  • Bruker APEX CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996 [triangle]) T min = 0.970, T max = 0.98
  • 10383 measured reflections
  • 2015 independent reflections
  • 1655 reflections with I > 2σ(I)
  • R int = 0.061

Refinement

  • R[F 2 > 2σ(F 2)] = 0.040
  • wR(F 2) = 0.083
  • S = 0.99
  • 2015 reflections
  • 271 parameters
  • 1 restraint
  • H-atom parameters constrained
  • Δρmax = 0.43 e Å−3
  • Δρmin = −0.16 e Å−3

Data collection: SMART (Bruker, 1997 [triangle]); cell refinement: SAINT (Bruker, 1999 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997 [triangle]); molecular graphics: SHELXTL-Plus (Sheldrick, 1990 [triangle]); software used to prepare material for publication: SHELXL97.

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536807065245/bg2156sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536807065245/bg2156Isup2.hkl

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

Acknowledgments

The authors acknowledge financial support from the One Hundred Talents Project of the Chinese Academy of Sciences and the National Natural Science Foundation of China (Project 20571071).

supplementary crystallographic information

Comment

Organic light-emitting diodes (OLEDs) have attracted considerable attentions due to potentially practical applications in large-area flat-panel display technologies, as well as to their numerous advantages, such as low cost, light weight, fast response, wide-viewing-angle, and compatibility with flexible substrates (Tang et al., 1987; Yeh et al., 2005).

It is well known that OLED produces light via recombination of electrons and holes, which are injected from electrodes on opposite sides of the device. Furthermore, the balance between the injection and transportation of electron and hole carriers leads to a high luminescence efficiency. Because triphenylamine and the 1,3,4-oxadiazol group possess good properties of hole transportation and electron deficiency, respectively, the compound containing these two groups should be of an increased electron affinity and transporting properties, resulting in a more balanced charge recombination in the emissive layer (Xiang et al., 2006; Chan et al., 1999; Gong et al., 1998). In this contribution, we have synthesized the title compound, C25H18N4O, with both a triphenylamine and a 1,3,4-oxadiazol moieties. This compound emits bright blue-green light under excitation of UV light, which implies its potential application in OLEDs.

The molecular skeleton of the title compound is non-planar (Fig.1), with the benzene (A), the 1,3,4-oxadiazol (B) and the pyridine (C) rings being slightly twisted with respect to each other (dihedral angles: (A),(B): 9.4 (4)°; (B),(C): 3.0 (4)°). Between the two adjacent molecules, the closest distances of C3-to-C7 and C4-to-C9 are 3.316 and 3.363 Å, respectively, indicating the existence of π–π interactions. (Fig 2).

Experimental

The title compound was synthesized via a tetrazole intermediate pathway. Amongst, the 4-tetrazoyltriphenylamine was prepared according to the procedures described elsewhere (Tamoto et al., 1997).

Firstly, the 150 ml water solution of 4-phenylpyridine (1 ml) and KMnO4 (3.16 g) was heated for 12 h. After removal of brown precipitate by filtration, the addition of concentrated hydrochloric acid into solution led to the deposition of white crystals. This solid was filtered, washed with water, and dried in the vacuo, and then was refluxed with thionyl chloride (15 ml) for 5 h. Isonicotinoyl chloride could be achieved by removing the solution by rotary evaporation.

A mixture of isonicotinoyl chloride (0.14 g), 4-tetrazolytriphenylamine (0.31 g), and dry pyridine (30 ml) was refluxed for one day under nitrogen atmosphere. After cooling, the reaction mixture was poured into water, and then filtered to collect the solid. The crude product was purified by column chromatography on silica gel with ethyl acetate/petroleum ether (1/5, v/v) as the eluent. Crystals suitable for X-ray diffraction study were obtained by slow evaporation of ethyl acetate/petroleum ether (1/5, v/v) solution.

Refinement

All H-atoms bound to carbon were refined using a riding model with d(C—H) = 0.93 Å, Uiso = 1.2Ueq (C). In the absence of significant anomalous scattering effects Friedel pairs have been merged

Figures

Fig. 1.
A view of the molecule of (I). Displacement ellipsoids drawn at a 30% probability level. H atoms omitted for clarity.
Fig. 2.
Packing view of (I) showing stacking interactions between neighbouring molecules. H atoms omitted for clarity.

Crystal data

C25H18N4OF000 = 816
Mr = 390.43Dx = 1.336 Mg m3
Orthorhombic, Pna21Mo Kα radiation λ = 0.71073 Å
Hall symbol: P 2c -2nCell parameters from 2767 reflections
a = 10.7125 (9) Åθ = 1.0–26.1º
b = 14.1797 (12) ŵ = 0.08 mm1
c = 12.7835 (11) ÅT = 291 (2) K
V = 1941.8 (3) Å3Block, yellow
Z = 40.40 × 0.30 × 0.25 mm

Data collection

Bruker APEX CCD area-detector diffractometer2015 independent reflections
Radiation source: fine-focus sealed tube1655 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.061
T = 291(2) Kθmax = 26.1º
ω scansθmin = 2.1º
Absorption correction: multi-scan(SADABS; Sheldrick, 1996)h = −13→13
Tmin = 0.970, Tmax = 0.98k = −9→17
10383 measured reflectionsl = −15→15

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.040H-atom parameters constrained
wR(F2) = 0.083  w = 1/[σ2(Fo2) + (0.037P)2] where P = (Fo2 + 2Fc2)/3
S = 0.99(Δ/σ)max < 0.001
2015 reflectionsΔρmax = 0.43 e Å3
271 parametersΔρmin = −0.16 e Å3
1 restraintExtinction correction: none
Primary atom site location: structure-invariant direct methods

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 (Å2)

xyzUiso*/Ueq
C11.5156 (3)0.7596 (2)1.1070 (3)0.0377 (8)
H11.57840.78601.14790.045*
C21.4338 (3)0.8198 (2)1.0564 (2)0.0342 (8)
H21.44240.88491.06270.041*
C31.4171 (3)0.6299 (2)1.0426 (3)0.0388 (8)
H31.41050.56471.03740.047*
C41.3304 (3)0.6843 (2)0.9899 (3)0.0349 (7)
H41.26740.65610.95080.042*
C51.3393 (3)0.7817 (2)0.9964 (3)0.0295 (7)
C61.2545 (3)0.8435 (2)0.9402 (2)0.0282 (7)
C71.1064 (3)0.8840 (2)0.8379 (2)0.0288 (7)
C81.0009 (3)0.8726 (2)0.7671 (2)0.0260 (7)
C90.9482 (3)0.7848 (2)0.7485 (2)0.0307 (7)
H90.98410.73110.77750.037*
C100.8425 (3)0.7771 (2)0.6870 (2)0.0311 (8)
H100.80720.71810.67510.037*
C110.9489 (3)0.9523 (2)0.7205 (2)0.0302 (7)
H110.98541.01100.73070.036*
C120.8434 (3)0.9442 (2)0.6590 (2)0.0314 (7)
H120.80890.99760.62820.038*
C130.7889 (3)0.8566 (2)0.6432 (2)0.0302 (7)
C140.7720 (3)0.8032 (2)0.4179 (3)0.0401 (8)
H140.82470.85500.42340.048*
C150.7824 (3)0.7427 (3)0.3339 (3)0.0466 (9)
H150.84370.75310.28370.056*
C160.7030 (3)0.6671 (3)0.3236 (3)0.0439 (9)
H160.70970.62680.26650.053*
C170.6136 (3)0.6518 (2)0.3988 (3)0.0401 (8)
H170.55910.60120.39170.048*
C180.6034 (3)0.7103 (2)0.4850 (3)0.0362 (8)
H180.54360.69840.53610.043*
C190.6827 (3)0.7865 (2)0.4944 (3)0.0300 (7)
C200.5715 (3)0.9019 (2)0.6056 (2)0.0303 (7)
C210.4767 (3)0.9129 (2)0.5323 (3)0.0352 (8)
H210.48560.88710.46580.042*
C220.3683 (3)0.9621 (2)0.5579 (3)0.0422 (9)
H220.30580.96910.50800.051*
C230.3527 (3)1.0006 (2)0.6560 (3)0.0431 (9)
H230.27951.03240.67300.052*
C240.4465 (3)0.9913 (2)0.7281 (3)0.0409 (8)
H240.43731.01860.79380.049*
C250.5545 (3)0.9421 (2)0.7050 (3)0.0336 (7)
H250.61630.93570.75560.040*
N11.5097 (2)0.66508 (19)1.1004 (2)0.0380 (7)
N21.2517 (2)0.93454 (17)0.9404 (2)0.0348 (6)
N31.1540 (2)0.96137 (17)0.8743 (2)0.0351 (6)
N40.6774 (2)0.84778 (18)0.58321 (19)0.0327 (6)
O11.16472 (18)0.80569 (14)0.87666 (16)0.0305 (5)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C10.0346 (19)0.041 (2)0.0379 (19)−0.0005 (16)−0.0046 (16)−0.0011 (16)
C20.0351 (18)0.0318 (18)0.0356 (18)−0.0032 (14)−0.0042 (15)−0.0010 (15)
C30.045 (2)0.0301 (18)0.042 (2)0.0010 (15)0.0019 (17)0.0038 (16)
C40.0359 (18)0.0350 (19)0.0339 (17)0.0002 (15)−0.0024 (16)−0.0048 (16)
C50.0289 (16)0.0333 (18)0.0264 (15)0.0002 (14)0.0040 (14)−0.0003 (15)
C60.0277 (16)0.0311 (18)0.0259 (15)−0.0001 (14)0.0001 (13)−0.0026 (15)
C70.0333 (17)0.0258 (17)0.0272 (16)0.0017 (14)0.0043 (14)0.0007 (14)
C80.0293 (16)0.0286 (16)0.0202 (15)0.0015 (13)0.0023 (13)−0.0012 (13)
C90.0405 (18)0.0240 (16)0.0276 (17)0.0045 (14)−0.0001 (15)0.0010 (14)
C100.0401 (19)0.0235 (16)0.0298 (17)−0.0036 (15)0.0019 (14)−0.0060 (14)
C110.0370 (18)0.0215 (16)0.0320 (17)−0.0020 (13)−0.0016 (14)−0.0014 (14)
C120.0404 (19)0.0246 (17)0.0290 (17)0.0033 (14)−0.0048 (15)−0.0013 (14)
C130.0331 (18)0.0319 (18)0.0255 (16)0.0032 (14)−0.0013 (14)−0.0046 (14)
C140.039 (2)0.043 (2)0.039 (2)−0.0064 (16)−0.0003 (16)−0.0032 (17)
C150.045 (2)0.061 (3)0.0339 (19)−0.0094 (19)0.0065 (17)−0.0104 (19)
C160.046 (2)0.051 (2)0.0353 (19)0.0038 (18)−0.0044 (17)−0.0171 (18)
C170.042 (2)0.0353 (19)0.043 (2)−0.0031 (16)−0.0064 (17)−0.0119 (17)
C180.0325 (17)0.043 (2)0.0335 (17)−0.0034 (15)0.0020 (15)−0.0056 (17)
C190.0282 (16)0.0310 (17)0.0308 (16)0.0034 (14)−0.0041 (14)−0.0037 (15)
C200.0330 (18)0.0243 (16)0.0337 (17)−0.0055 (14)0.0009 (14)0.0037 (14)
C210.0392 (19)0.0337 (18)0.0326 (18)−0.0050 (15)0.0013 (15)0.0010 (15)
C220.038 (2)0.0335 (19)0.055 (2)−0.0006 (16)−0.0036 (17)0.0073 (19)
C230.038 (2)0.037 (2)0.054 (2)0.0032 (16)0.0106 (18)0.0001 (18)
C240.047 (2)0.0340 (19)0.042 (2)0.0004 (17)0.0142 (18)−0.0038 (16)
C250.0373 (19)0.0295 (17)0.0341 (18)−0.0020 (15)0.0022 (15)−0.0010 (15)
N10.0404 (16)0.0352 (16)0.0384 (16)0.0037 (14)−0.0030 (14)0.0026 (14)
N20.0363 (15)0.0314 (15)0.0366 (15)0.0009 (12)−0.0068 (13)0.0016 (13)
N30.0356 (15)0.0306 (15)0.0389 (15)0.0001 (12)−0.0070 (13)−0.0010 (13)
N40.0290 (14)0.0345 (15)0.0346 (15)0.0025 (12)−0.0057 (12)−0.0114 (13)
O10.0343 (12)0.0282 (12)0.0291 (11)0.0017 (9)−0.0038 (10)−0.0009 (10)

Geometric parameters (Å, °)

C1—N11.344 (4)C13—N41.425 (4)
C1—C21.384 (4)C14—C151.380 (4)
C1—H10.9300C14—C191.388 (4)
C2—C51.380 (4)C14—H140.9300
C2—H20.9300C15—C161.375 (5)
C3—N11.333 (4)C15—H150.9300
C3—C41.382 (4)C16—C171.374 (5)
C3—H30.9300C16—H160.9300
C4—C51.387 (4)C17—C181.383 (4)
C4—H40.9300C17—H170.9300
C5—C61.452 (4)C18—C191.380 (4)
C6—N21.292 (3)C18—H180.9300
C6—O11.368 (3)C19—N41.430 (4)
C7—N31.296 (4)C20—C211.390 (4)
C7—O11.367 (3)C20—N41.399 (4)
C7—C81.456 (4)C20—C251.405 (4)
C8—C91.387 (4)C21—C221.393 (4)
C8—C111.393 (4)C21—H210.9300
C9—C101.383 (4)C22—C231.379 (5)
C9—H90.9300C22—H220.9300
C10—C131.384 (4)C23—C241.370 (5)
C10—H100.9300C23—H230.9300
C11—C121.381 (4)C24—C251.383 (4)
C11—H110.9300C24—H240.9300
C12—C131.388 (4)C25—H250.9300
C12—H120.9300N2—N31.398 (3)
N1—C1—C2123.8 (3)C19—C14—H14120.0
N1—C1—H1118.1C16—C15—C14120.6 (3)
C2—C1—H1118.1C16—C15—H15119.7
C5—C2—C1118.8 (3)C14—C15—H15119.7
C5—C2—H2120.6C17—C16—C15119.2 (3)
C1—C2—H2120.6C17—C16—H16120.4
N1—C3—C4124.2 (3)C15—C16—H16120.4
N1—C3—H3117.9C16—C17—C18121.2 (3)
C4—C3—H3117.9C16—C17—H17119.4
C3—C4—C5118.7 (3)C18—C17—H17119.4
C3—C4—H4120.7C19—C18—C17119.4 (3)
C5—C4—H4120.7C19—C18—H18120.3
C2—C5—C4118.3 (3)C17—C18—H18120.3
C2—C5—C6119.8 (3)C18—C19—C14119.7 (3)
C4—C5—C6121.9 (3)C18—C19—N4121.3 (3)
N2—C6—O1112.1 (3)C14—C19—N4118.9 (3)
N2—C6—C5128.1 (3)C21—C20—N4121.1 (3)
O1—C6—C5119.8 (3)C21—C20—C25118.0 (3)
N3—C7—O1112.2 (3)N4—C20—C25120.8 (3)
N3—C7—C8128.5 (3)C20—C21—C22120.4 (3)
O1—C7—C8119.3 (3)C20—C21—H21119.8
C9—C8—C11119.4 (3)C22—C21—H21119.8
C9—C8—C7121.4 (3)C23—C22—C21120.9 (3)
C11—C8—C7119.1 (3)C23—C22—H22119.6
C10—C9—C8120.2 (3)C21—C22—H22119.6
C10—C9—H9119.9C24—C23—C22119.0 (3)
C8—C9—H9119.9C24—C23—H23120.5
C9—C10—C13120.3 (3)C22—C23—H23120.5
C9—C10—H10119.8C23—C24—C25121.2 (3)
C13—C10—H10119.8C23—C24—H24119.4
C12—C11—C8120.3 (3)C25—C24—H24119.4
C12—C11—H11119.9C24—C25—C20120.4 (3)
C8—C11—H11119.9C24—C25—H25119.8
C11—C12—C13120.1 (3)C20—C25—H25119.8
C11—C12—H12120.0C3—N1—C1116.3 (3)
C13—C12—H12120.0C6—N2—N3106.8 (2)
C10—C13—C12119.8 (3)C7—N3—N2106.3 (2)
C10—C13—N4119.6 (3)C20—N4—C13121.4 (2)
C12—C13—N4120.6 (3)C20—N4—C19121.8 (2)
C15—C14—C19119.9 (3)C13—N4—C19116.6 (2)
C15—C14—H14120.0C7—O1—C6102.6 (2)
N1—C1—C2—C50.8 (5)N4—C20—C21—C22176.1 (3)
N1—C3—C4—C50.3 (5)C25—C20—C21—C22−0.3 (4)
C1—C2—C5—C40.2 (5)C20—C21—C22—C23−0.2 (5)
C1—C2—C5—C6−178.3 (3)C21—C22—C23—C241.2 (5)
C3—C4—C5—C2−0.7 (5)C22—C23—C24—C25−1.7 (5)
C3—C4—C5—C6177.8 (3)C23—C24—C25—C201.2 (5)
C2—C5—C6—N2−2.4 (5)C21—C20—C25—C24−0.2 (4)
C4—C5—C6—N2179.2 (3)N4—C20—C25—C24−176.6 (3)
C2—C5—C6—O1176.7 (3)C4—C3—N1—C10.7 (5)
C4—C5—C6—O1−1.7 (4)C2—C1—N1—C3−1.2 (5)
N3—C7—C8—C9−169.3 (3)O1—C6—N2—N30.7 (3)
O1—C7—C8—C98.3 (4)C5—C6—N2—N3179.8 (3)
N3—C7—C8—C118.1 (5)O1—C7—N3—N21.0 (3)
O1—C7—C8—C11−174.3 (3)C8—C7—N3—N2178.8 (3)
C11—C8—C9—C10−2.2 (4)C6—N2—N3—C7−1.0 (3)
C7—C8—C9—C10175.2 (3)C21—C20—N4—C13162.2 (3)
C8—C9—C10—C130.3 (4)C25—C20—N4—C13−21.5 (4)
C9—C8—C11—C122.1 (4)C21—C20—N4—C19−12.8 (4)
C7—C8—C11—C12−175.4 (3)C25—C20—N4—C19163.5 (3)
C8—C11—C12—C13−0.2 (4)C10—C13—N4—C20126.7 (3)
C9—C10—C13—C121.6 (4)C12—C13—N4—C20−52.7 (4)
C9—C10—C13—N4−177.7 (3)C10—C13—N4—C19−58.1 (4)
C11—C12—C13—C10−1.6 (4)C12—C13—N4—C19122.6 (3)
C11—C12—C13—N4177.7 (3)C18—C19—N4—C20−63.3 (4)
C19—C14—C15—C161.6 (5)C14—C19—N4—C20118.5 (3)
C14—C15—C16—C17−0.7 (5)C18—C19—N4—C13121.5 (3)
C15—C16—C17—C18−0.8 (5)C14—C19—N4—C13−56.7 (4)
C16—C17—C18—C191.3 (5)N3—C7—O1—C6−0.6 (3)
C17—C18—C19—C14−0.4 (5)C8—C7—O1—C6−178.6 (2)
C17—C18—C19—N4−178.6 (3)N2—C6—O1—C7−0.1 (3)
C15—C14—C19—C18−1.1 (5)C5—C6—O1—C7−179.3 (3)
C15—C14—C19—N4177.2 (3)

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: BG2156).

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