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Acta Cryst. (2009). E65, o1187    [ doi:10.1107/S1600536809016195 ]

6-(1H-Indol-3-yl)-4-phenyl-2,2'-bipyridine-5-carbonitrile

W. Zhu, Y. Xiang and S. Zhu

Abstract top

In the molecule of the title compound, C25H16N4, the pyridine rings are oriented at a dihedral angle of 0.92 (3)°, while the dihedral angle between the benzene ring and the adjacent pyridine ring is 56.51 (3)°. In the crystal structure, intermolecular N-H...N hydrogen bonds link the molecules into centrosymmetric dimers, forming R22(16) ring motifs. [pi]-[pi] contacts between the pyridine ring and the indole ring system and between the pyridine rings [centroid-centroid distances = 3.923 (2) and 3.724 (2) Å] may further stabilize the structure. Two weak C-H...[pi] interactions are also present.

Comment top

Indole nucleus is a well known heterocycle (da Silva et al., 2001). Compounds carrying the indole moiety exhibit antibacterial and fungicidal activities (Joshi & Chand, 1982). Moreover, the bipyridines and the related complexes have also found numerous applications in asymmetric catalysis, photoinduced electron transfer, and polymer and dendrimer science (Namba et al., 2005). As a part of our programme devoted to the preparation of functionalized indole derivatives, we synthesized a series of indole substituted heterocycles (Zhu et al., 2008). We report herein the crystal structure of the title compound.

In the molecule of the title compound (Fig 1), the bond lengths (Allen et al., 1987) and angles are within normal ranges. The indole ring system A (N4/C18-C25) is planar with a maximum deviation of -0.021 (3) Å for atom C25. Rings B (N1/C1-C5), C (N2/C6-C10) and D (C11-C16) are, of course, planar, and they are oriented at dihedral angles of A/B = 23.01 (3), A/C = 23.61 (3), A/D = 74.90 (3), B/C = 0.92 (3), B/D = 56.51 (3) and C/D = 56.51 (3) °. So, rings B and C are nearly coplanar.

In the crystal structure, intermolecular N-H···N hydrogen bonds (Table 1) link the molecules into centrosymmetric dimers forming R22(16) ring motifs (Fig. 2) (Bernstein et al., 1995), in which they may be effective in the stabilization of the structure. The π–π contacts between the pyridine ring and the indole ring system and the pyridine rings, Cg1—Cg2i and Cg2—Cg3ii [symmetry codes: (i) -x, 2 - y, 1 - z, (ii) -x, 1 - y, 1 - z, where Cg1, Cg2 and Cg3 are centroids of the rings (N4/C18-C20/C25), B (N1/C1-C5) and C (N2/C6-C10), respectively] may further stabilize the structure, with centroid-centroid distances of 3.923 (2) and 3.724 (2) Å. There also exist two weak C—H···π interactions (Table 1).

Related literature top

For general background, see: da Silva et al. (2001); Joshi & Chand (1982); Namba et al. (2005). For a related structure, see: Zhu et al., (2008). For bond-length data, see: Allen et al. (1987). For ring-motifs, see: Bernstein et al. (1995). Cg4 and Cg5 are the centroids of the C11–C16 and C20–C25 rings, respectively.

Experimental top

The title compound was prepared by one-pot reaction of 3-cyanoacetyl indole (2 mmol), benzaldehyde (2 mmol) and 2-acetyl pyridine (2 mmol) in present of ammonium acetate in ethanol. After refluxing for 5 h, the reaction mixture was cooled and washed with small amount of cool ethanol. The crude product was filtered and single crystals of the title compound were obtained from ethanol solution by slow evaporation at room temperature (yield; 80%, m.p. 567-568 K). Spectroscopic analysis: IR (KBr, n, cm-1): 3337, 3050, 2218, 1573, 1535, 1438, 1214, 1145, 850, 745, 703. 1H NMR (400 MHz, DMSO-d6): 11.89 (br s, 1H, NH), 8.78 (d, J = 4.4 Hz, 1H, ArH), 8.58 (d, J = 8.0 Hz, 1H, ArH), 8.41 (d, J = 5.2 Hz, 2H, ArH), 8.31 (s, 1H, ArH), 8.11 (m, 1H, ArH), 7.79-7.81 (m, 2H, ArH), 7.56-7.66 (m, 5H, ArH), 7.24-7.29 (m, 2H, ArH)

Refinement top

H atoms were positioned geometrically, with N-H = 0.86 Å (for NH) and C-H = 0.93 Å for aromatic H and constrained to ride on their parent atoms with Uiso(H) = 1.2Ueq(C,N).

Computing details top

Data collection: CrystalClear (Rigaku/MSC, 2001); cell refinement: CrystalClear (Rigaku/MSC, 2001); data reduction: CrystalStructure (Rigaku/MSC, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPII (Johnson, 1976) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 2] Fig. 2. A partial packing diagram of the title compound. Hydrogen bonds are shown as dashed lines.
6-(1H-Indol-3-yl)-4-phenyl-2,2'-bipyridine-5-carbonitrile top
Crystal data top
C25H16N4Z = 2
Mr = 372.42F000 = 388
Triclinic, P1Dx = 1.342 Mg m−3
Hall symbol: -P 1Melting point = 567–568 K
a = 9.7744 (16) ÅMo Kα radiation
λ = 0.71070 Å
b = 9.7927 (11) ÅCell parameters from 3008 reflections
c = 11.233 (2) Åθ = 3.1–25.3º
α = 73.121 (13)ºµ = 0.08 mm−1
β = 86.008 (16)ºT = 291 K
γ = 63.853 (10)ºBlock, yellow
V = 921.5 (3) Å30.55 × 0.35 × 0.30 mm
Data collection top
Rigaku Mercury
diffractometer		3349 independent reflections
Radiation source: fine-focus sealed tube2614 reflections with I > 2/s(I)
Monochromator: graphiteRint = 0.027
Detector resolution: 7.31 pixels mm-1θmax = 25.3º
T = 291 Kθmin = 3.1º
ω scansh = −11→11
Absorption correction: multi-scan
(ABSCOR; Jacobson, 1998)		k = −10→11
Tmin = 0.966, Tmax = 0.976l = −13→13
8987 measured 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)] = 0.054H-atom parameters constrained
wR(F2) = 0.126  w = 1/[σ2(Fo2) + (0.0538P)2 + 0.1499P]
where P = (Fo2 + 2Fc2)/3
S = 1.12(Δ/σ)max < 0.001
3349 reflectionsΔρmax = 0.16 e Å−3
263 parametersΔρmin = −0.20 e Å−3
Primary atom site location: structure-invariant direct methodsExtinction correction: none
Crystal data top
C25H16N4γ = 63.853 (10)º
Mr = 372.42V = 921.5 (3) Å3
Triclinic, P1Z = 2
a = 9.7744 (16) ÅMo Kα
b = 9.7927 (11) ŵ = 0.08 mm−1
c = 11.233 (2) ÅT = 291 K
α = 73.121 (13)º0.55 × 0.35 × 0.30 mm
β = 86.008 (16)º
Data collection top
Rigaku Mercury
diffractometer		3349 independent reflections
Absorption correction: multi-scan
(ABSCOR; Jacobson, 1998)		2614 reflections with I > 2/s(I)
Tmin = 0.966, Tmax = 0.976Rint = 0.027
8987 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.054263 parameters
wR(F2) = 0.126H-atom parameters constrained
S = 1.12Δρmax = 0.16 e Å−3
3349 reflectionsΔρmin = −0.20 e Å−3
Special details top

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) top
xyzUiso*/Ueq
N10.94201 (16)0.20772 (17)0.54741 (13)0.0355 (4)
N21.20413 (18)0.3774 (2)0.44026 (14)0.0455 (4)
N30.5855 (2)0.1895 (2)0.28547 (16)0.0606 (5)
N40.64100 (17)−0.04598 (18)0.69177 (14)0.0422 (4)
H40.5936−0.10430.70250.051*
C11.01436 (19)0.2799 (2)0.46717 (16)0.0347 (4)
C20.98275 (19)0.3310 (2)0.33960 (16)0.0371 (4)
H21.03820.37760.28730.045*
C30.86846 (19)0.3126 (2)0.28960 (16)0.0353 (4)
C40.79281 (19)0.2362 (2)0.37308 (16)0.0348 (4)
C50.83308 (19)0.1829 (2)0.50305 (16)0.0334 (4)
C61.13427 (19)0.3032 (2)0.52184 (16)0.0354 (4)
C71.1727 (2)0.2494 (2)0.64913 (18)0.0449 (5)
H71.12260.19810.70390.054*
C81.2862 (2)0.2731 (3)0.6929 (2)0.0519 (5)
H81.31350.23830.77790.062*
C91.3586 (2)0.3482 (2)0.6104 (2)0.0494 (5)
H91.43610.36480.63780.059*
C101.3136 (2)0.3981 (3)0.4861 (2)0.0521 (5)
H101.36250.44970.43020.063*
C110.8284 (2)0.3777 (2)0.15322 (16)0.0379 (4)
C120.9407 (2)0.3356 (2)0.07066 (17)0.0445 (5)
H121.04000.26170.10100.053*
C130.9065 (3)0.4026 (3)−0.05660 (18)0.0529 (6)
H130.98230.3725−0.11140.063*
C140.7602 (3)0.5140 (3)−0.10229 (19)0.0555 (6)
H140.73760.5599−0.18780.067*
C150.6484 (3)0.5570 (3)−0.02151 (19)0.0532 (6)
H150.54980.6323−0.05250.064*
C160.6809 (2)0.4891 (2)0.10587 (18)0.0460 (5)
H160.60390.51810.16000.055*
C170.6772 (2)0.2108 (2)0.32443 (17)0.0423 (5)
C180.7603 (2)0.1025 (2)0.59690 (16)0.0352 (4)
C190.6856 (2)0.0176 (2)0.58127 (17)0.0385 (4)
H190.66820.00560.50540.046*
C200.6833 (2)−0.0028 (2)0.78422 (17)0.0380 (4)
C210.6582 (2)−0.0376 (2)0.90989 (18)0.0476 (5)
H210.6081−0.10010.94440.057*
C220.7105 (3)0.0240 (3)0.98141 (19)0.0568 (6)
H220.69570.00291.06630.068*
C230.7851 (3)0.1175 (3)0.92946 (19)0.0601 (6)
H230.81880.15810.98030.072*
C240.8104 (2)0.1515 (3)0.80452 (18)0.0507 (5)
H240.86050.21430.77110.061*
C250.7595 (2)0.0901 (2)0.72879 (16)0.0366 (4)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0353 (8)0.0367 (9)0.0374 (8)−0.0191 (7)0.0027 (7)−0.0097 (7)
N20.0430 (9)0.0583 (11)0.0475 (9)−0.0321 (8)0.0058 (8)−0.0173 (8)
N30.0675 (12)0.0748 (13)0.0507 (10)−0.0502 (11)−0.0130 (9)0.0006 (9)
N40.0439 (9)0.0449 (9)0.0476 (9)−0.0298 (8)0.0052 (7)−0.0109 (7)
C10.0320 (9)0.0349 (10)0.0378 (10)−0.0153 (8)0.0024 (8)−0.0102 (8)
C20.0336 (9)0.0415 (11)0.0369 (10)−0.0206 (8)0.0024 (8)−0.0058 (8)
C30.0354 (10)0.0346 (10)0.0355 (10)−0.0159 (8)0.0005 (8)−0.0081 (8)
C40.0346 (9)0.0346 (10)0.0362 (10)−0.0172 (8)0.0001 (8)−0.0082 (8)
C50.0329 (9)0.0314 (9)0.0385 (10)−0.0157 (8)0.0034 (8)−0.0114 (8)
C60.0319 (9)0.0355 (10)0.0407 (10)−0.0152 (8)0.0036 (8)−0.0134 (8)
C70.0452 (11)0.0490 (12)0.0415 (11)−0.0237 (10)−0.0025 (9)−0.0083 (9)
C80.0514 (12)0.0575 (13)0.0492 (12)−0.0256 (11)−0.0101 (10)−0.0131 (10)
C90.0334 (10)0.0567 (13)0.0663 (14)−0.0199 (10)−0.0016 (10)−0.0281 (11)
C100.0458 (12)0.0661 (14)0.0611 (13)−0.0364 (11)0.0121 (10)−0.0249 (11)
C110.0418 (10)0.0419 (11)0.0360 (10)−0.0255 (9)0.0003 (8)−0.0080 (8)
C120.0459 (11)0.0509 (12)0.0399 (11)−0.0266 (10)0.0016 (9)−0.0089 (9)
C130.0668 (14)0.0664 (15)0.0398 (11)−0.0420 (13)0.0114 (10)−0.0171 (10)
C140.0770 (16)0.0650 (15)0.0357 (11)−0.0472 (13)−0.0048 (11)−0.0026 (10)
C150.0566 (13)0.0545 (13)0.0463 (12)−0.0306 (11)−0.0118 (11)0.0018 (10)
C160.0448 (11)0.0539 (12)0.0410 (10)−0.0260 (10)−0.0005 (9)−0.0085 (9)
C170.0457 (11)0.0469 (12)0.0382 (10)−0.0283 (10)0.0001 (9)−0.0042 (9)
C180.0334 (9)0.0345 (10)0.0388 (10)−0.0164 (8)0.0030 (8)−0.0098 (8)
C190.0408 (10)0.0398 (11)0.0387 (10)−0.0215 (9)0.0030 (8)−0.0109 (8)
C200.0339 (10)0.0373 (10)0.0436 (11)−0.0174 (8)0.0041 (8)−0.0105 (8)
C210.0476 (12)0.0545 (13)0.0449 (11)−0.0305 (10)0.0111 (9)−0.0091 (10)
C220.0709 (15)0.0729 (15)0.0377 (11)−0.0436 (13)0.0129 (10)−0.0146 (11)
C230.0815 (16)0.0805 (16)0.0432 (12)−0.0570 (14)0.0122 (11)−0.0205 (11)
C240.0656 (14)0.0626 (13)0.0424 (11)−0.0457 (12)0.0096 (10)−0.0145 (10)
C250.0356 (10)0.0374 (10)0.0394 (10)−0.0199 (8)0.0033 (8)−0.0091 (8)
Geometric parameters (Å, °) top
N1—C11.339 (2)C11—C121.385 (3)
N1—C51.347 (2)C11—C161.391 (3)
N2—C101.334 (2)C12—C131.384 (3)
N2—C61.341 (2)C12—H120.9300
N3—C171.144 (2)C13—C141.378 (3)
N4—C191.354 (2)C13—H130.9300
N4—C201.377 (2)C14—C151.369 (3)
N4—H40.8600C14—H140.9300
C1—C21.381 (2)C15—C161.384 (3)
C1—C61.490 (2)C15—H150.9300
C2—C31.385 (2)C16—H160.9300
C2—H20.9300C18—C191.375 (2)
C3—C41.404 (2)C18—C251.451 (2)
C3—C111.484 (2)C19—H190.9300
C4—C51.420 (2)C20—C211.384 (3)
C4—C171.432 (2)C20—C251.405 (2)
C5—C181.465 (2)C21—C221.372 (3)
C6—C71.388 (2)C21—H210.9300
C7—C81.377 (3)C22—C231.389 (3)
C7—H70.9300C22—H220.9300
C8—C91.368 (3)C23—C241.376 (3)
C8—H80.9300C23—H230.9300
C9—C101.371 (3)C24—C251.398 (3)
C9—H90.9300C24—H240.9300
C10—H100.9300
C1—N1—C5119.18 (15)C13—C12—H12119.7
C10—N2—C6117.30 (17)C11—C12—H12119.7
C19—N4—C20109.41 (15)C14—C13—C12120.1 (2)
C19—N4—H4125.3C14—C13—H13119.9
C20—N4—H4125.3C12—C13—H13119.9
N1—C1—C2123.09 (15)C15—C14—C13119.85 (19)
N1—C1—C6116.67 (15)C15—C14—H14120.1
C2—C1—C6120.24 (16)C13—C14—H14120.1
C1—C2—C3119.94 (16)C14—C15—C16120.5 (2)
C1—C2—H2120.0C14—C15—H15119.8
C3—C2—H2120.0C16—C15—H15119.8
C2—C3—C4117.25 (16)C15—C16—C11120.2 (2)
C2—C3—C11119.47 (16)C15—C16—H16119.9
C4—C3—C11123.25 (15)C11—C16—H16119.9
C3—C4—C5120.12 (15)N3—C17—C4179.5 (2)
C3—C4—C17118.82 (15)C19—C18—C25105.64 (15)
C5—C4—C17121.05 (16)C19—C18—C5128.12 (16)
N1—C5—C4120.37 (15)C25—C18—C5126.18 (15)
N1—C5—C18115.71 (15)N4—C19—C18110.50 (16)
C4—C5—C18123.91 (15)N4—C19—H19124.7
N2—C6—C7122.15 (16)C18—C19—H19124.7
N2—C6—C1115.83 (15)N4—C20—C21129.29 (17)
C7—C6—C1122.01 (16)N4—C20—C25107.56 (15)
C8—C7—C6118.82 (18)C21—C20—C25123.15 (17)
C8—C7—H7120.6C22—C21—C20117.15 (18)
C6—C7—H7120.6C22—C21—H21121.4
C9—C8—C7119.50 (19)C20—C21—H21121.4
C9—C8—H8120.2C21—C22—C23121.23 (19)
C7—C8—H8120.2C21—C22—H22119.4
C8—C9—C10118.03 (18)C23—C22—H22119.4
C8—C9—H9121.0C24—C23—C22121.5 (2)
C10—C9—H9121.0C24—C23—H23119.2
N2—C10—C9124.20 (19)C22—C23—H23119.2
N2—C10—H10117.9C23—C24—C25118.88 (18)
C9—C10—H10117.9C23—C24—H24120.6
C12—C11—C16118.78 (17)C25—C24—H24120.6
C12—C11—C3119.99 (16)C24—C25—C20118.06 (17)
C16—C11—C3121.11 (17)C24—C25—C18135.01 (17)
C13—C12—C11120.51 (19)C20—C25—C18106.88 (15)
C5—N1—C1—C20.0 (3)C16—C11—C12—C13−0.3 (3)
C5—N1—C1—C6−179.68 (15)C3—C11—C12—C13−176.21 (17)
N1—C1—C2—C32.0 (3)C11—C12—C13—C141.0 (3)
C6—C1—C2—C3−178.34 (16)C12—C13—C14—C15−0.7 (3)
C1—C2—C3—C4−2.2 (3)C13—C14—C15—C16−0.1 (3)
C1—C2—C3—C11175.87 (17)C14—C15—C16—C110.8 (3)
C2—C3—C4—C50.7 (3)C12—C11—C16—C15−0.5 (3)
C11—C3—C4—C5−177.30 (16)C3—C11—C16—C15175.28 (17)
C2—C3—C4—C17−178.14 (16)N1—C5—C18—C19−157.15 (17)
C11—C3—C4—C173.8 (3)C4—C5—C18—C1924.1 (3)
C1—N1—C5—C4−1.6 (2)N1—C5—C18—C2519.5 (3)
C1—N1—C5—C18179.67 (15)C4—C5—C18—C25−159.21 (17)
C3—C4—C5—N11.2 (3)C20—N4—C19—C180.8 (2)
C17—C4—C5—N1−179.95 (17)C25—C18—C19—N4−0.5 (2)
C3—C4—C5—C18179.84 (16)C5—C18—C19—N4176.68 (17)
C17—C4—C5—C18−1.3 (3)C19—N4—C20—C21178.41 (19)
C10—N2—C6—C70.0 (3)C19—N4—C20—C25−0.8 (2)
C10—N2—C6—C1−179.08 (16)N4—C20—C21—C22−178.64 (19)
N1—C1—C6—N2−179.21 (15)C25—C20—C21—C220.5 (3)
C2—C1—C6—N21.1 (3)C20—C21—C22—C230.1 (3)
N1—C1—C6—C71.7 (3)C21—C22—C23—C24−0.3 (4)
C2—C1—C6—C7−178.01 (17)C22—C23—C24—C250.0 (4)
N2—C6—C7—C80.0 (3)C23—C24—C25—C200.6 (3)
C1—C6—C7—C8179.07 (17)C23—C24—C25—C18177.8 (2)
C6—C7—C8—C9−0.3 (3)N4—C20—C25—C24178.46 (16)
C7—C8—C9—C100.4 (3)C21—C20—C25—C24−0.8 (3)
C6—N2—C10—C90.2 (3)N4—C20—C25—C180.5 (2)
C8—C9—C10—N2−0.4 (3)C21—C20—C25—C18−178.79 (17)
C2—C3—C11—C1254.4 (2)C19—C18—C25—C24−177.5 (2)
C4—C3—C11—C12−127.63 (19)C5—C18—C25—C245.3 (3)
C2—C3—C11—C16−121.39 (19)C19—C18—C25—C200.0 (2)
C4—C3—C11—C1656.6 (3)C5—C18—C25—C20−177.27 (16)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N4—H4···N3i0.862.233.066 (2)164
C12—H12···Cg5ii0.932.843.649 (3)146
C23—H23···Cg4iii0.932.913.711 (3)145
Symmetry codes: (i) −x+1, −y, −z+1; (ii) −x, −y+2, −z+1; (iii) x, y, z−1.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N4—H4···N3i0.862.233.066 (2)164
C12—H12···Cg5ii0.932.843.649 (3)146
C23—H23···Cg4iii0.932.913.711 (3)145
Symmetry codes: (i) −x+1, −y, −z+1; (ii) −x, −y+2, −z+1; (iii) x, y, z−1.
Acknowledgements top

This work was sponsored by the `Qing Lan' Project of Jiangsu Province for Excellent Young Teachers of XuZhou College of Industrial Technology, and the Special Foundation of the President of Xuzhou Medical College.

references
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