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Acta Cryst. (2009). E65, o1332    [ doi:10.1107/S1600536809017759 ]

1,1',2,2'-Tetramethyl-3,3'-(4-methoxybenzylidene)di-1H-indole

C.-L. Zhang, P.-P. Ye and Z.-Q. Du

Abstract top

The title compound, C28H28N2O, was prepared by condensation of 1,2-bimethylindole and 4-methoxybenzaldehyde. In the molecular structure, the plane of the non-fused benzene ring is twisted with respect to the planes of the two indole ring systems, exhibiting dihedral angles of 72.04 (7) and 72.24 (7)°, while the planes of the two indole ring systems are oriented at a dihedral angle of 87.05 (5)°. Neither hydrogen bonding nor [pi]-[pi] stacking is observed in the crystal structure.

Comment top

Indole derivatives are found abundantly in a variety of natural plants and exhibit various physiological properties (Poter et al., 1977; Sundberg, 1996). Among them, bis-indolymethane derivatives are found to be kinds of potentially bioactive compounds (Chang et al., 1999; Ge et al., 1999). In recent years, the synthesis and application of bis-indolymethane derivatives have been widely studied (Osawa & Namiki, 1983; Morris & Andersen, 1990; Azizian et al., 2007). The title compound is one of bis-indolymethane derivatives. We report here its crystal structure.

The molecular structure of the title compound is shown in Fig. 1. The C2-benzene ring is twisted to the two indole rings with the dihedral angles of 72.04 (7)° and 72.24 (7)°, respectively. Two indole rings make a dihedral angle of 87.86 (3)° to each other. Neither hydrogen bonding nor π-π stacking is observed in the crystal structure.

Related literature top

For general background to thephysiological properties of indole derivatives, see: Poter et al. (1977); Sundberg (1996). For related structures, see: Chang et al. (1999); Ge et al. (1999); Morris & Andersen (1990); Azizian et al. (2007); Osawa & Namiki (1983). For the synthesis, see: Deb & Bhuyan (2006).

Experimental top

The title compound was prepared according to the procedure reported by Deb & Bhuyan (2006). 1,2-Bimethylindole (2.0 mmol) and p-methoxybenzaldehyde (1.0 mmol) were dissolved in methanol (5 ml). The solution was stirred at room temperature for 5 h, then the solvent was removed under vacuum and the crude product was purified by silica-gel flash column chromatography. Single crystals suitable for X-ray data collection were obtained by recrystallization from chloroform/hexane.

Refinement top

H atoms were located geometrically and treated as riding, with C—H = 0.93 (aromatic), 0.96 (methyl) and 0.98 Å (methine), and Uiso(H) = 1.5Ueq(C) for methyl and 1.2Ueq(C) for the others.

Computing details top

Data collection: SMART (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) with 30% probability displacement ellipsoids.
1,1',2,2'-Tetramethyl-3,3'-(4-methoxybenzylidene)di-1H-indole top
Crystal data top
C28H28N2OF000 = 872
Mr = 408.52Dx = 1.202 Mg m−3
Monoclinic, P21/nMo Kα radiation
λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 6354 reflections
a = 10.6647 (8) Åθ = 4.9–51.2º
b = 13.2088 (10) ŵ = 0.07 mm−1
c = 16.1494 (13) ÅT = 296 K
β = 97.1740 (10)ºPrism, colorless
V = 2257.1 (3) Å30.25 × 0.24 × 0.21 mm
Z = 4
Data collection top
Bruker SMART CCD area-detector
diffractometer		3196 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.025
Monochromator: graphiteθmax = 25.0º
T = 296 Kθmin = 2.0º
φ and ω scansh = −12→12
Absorption correction: nonek = −15→15
11505 measured reflectionsl = −19→19
3955 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)] = 0.044H-atom parameters constrained
wR(F2) = 0.139  w = 1/[σ2(Fo2) + (0.1047P)2 + 0.8752P]
where P = (Fo2 + 2Fc2)/3
S = 0.83(Δ/σ)max < 0.001
3955 reflectionsΔρmax = 0.21 e Å−3
285 parametersΔρmin = −0.22 e Å−3
Primary atom site location: structure-invariant direct methodsExtinction correction: none
Crystal data top
C28H28N2OV = 2257.1 (3) Å3
Mr = 408.52Z = 4
Monoclinic, P21/nMo Kα
a = 10.6647 (8) ŵ = 0.07 mm−1
b = 13.2088 (10) ÅT = 296 K
c = 16.1494 (13) Å0.25 × 0.24 × 0.21 mm
β = 97.1740 (10)º
Data collection top
Bruker SMART CCD area-detector
diffractometer		3955 independent reflections
Absorption correction: none3196 reflections with I > 2σ(I)
11505 measured reflectionsRint = 0.025
Refinement top
R[F2 > 2σ(F2)] = 0.044285 parameters
wR(F2) = 0.139H-atom parameters constrained
S = 0.83Δρmax = 0.21 e Å−3
3955 reflectionsΔρmin = −0.22 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
N10.63286 (14)0.32330 (11)0.89904 (8)0.0421 (4)
N20.23060 (12)0.47645 (10)0.62297 (8)0.0358 (3)
O10.73808 (18)0.09952 (13)0.43460 (10)0.0827 (5)
C10.54764 (14)0.35901 (11)0.67122 (9)0.0316 (3)
H10.59370.42260.66710.038*
C20.59177 (14)0.28915 (11)0.60516 (9)0.0334 (4)
C30.72045 (16)0.27569 (12)0.60290 (11)0.0403 (4)
H30.77760.30970.64140.048*
C40.76556 (18)0.21341 (14)0.54521 (12)0.0501 (5)
H40.85220.20660.54460.060*
C50.6831 (2)0.16106 (14)0.48826 (12)0.0529 (5)
C60.5550 (2)0.17324 (15)0.48860 (12)0.0544 (5)
H60.49840.13870.45020.065*
C70.51073 (17)0.23765 (13)0.54694 (11)0.0435 (4)
H70.42400.24600.54640.052*
C80.6598 (4)0.0526 (3)0.36972 (17)0.1146 (13)
H8A0.71070.01590.33490.172*
H8B0.61130.10310.33710.172*
H8C0.60360.00660.39270.172*
C90.58732 (14)0.32027 (11)0.75930 (9)0.0319 (3)
C100.62303 (14)0.21961 (11)0.78731 (10)0.0317 (3)
C110.63396 (15)0.12468 (12)0.74924 (10)0.0373 (4)
H110.61470.11770.69180.045*
C120.67336 (16)0.04226 (12)0.79772 (11)0.0423 (4)
H120.6806−0.02030.77240.051*
C130.70262 (16)0.05046 (13)0.88377 (11)0.0446 (4)
H130.7297−0.00650.91480.054*
C140.69222 (16)0.14123 (14)0.92376 (11)0.0428 (4)
H140.71170.14670.98130.051*
C150.65141 (14)0.22480 (12)0.87502 (10)0.0355 (4)
C160.59485 (15)0.38016 (12)0.82871 (10)0.0377 (4)
C170.6468 (2)0.35910 (17)0.98459 (12)0.0627 (6)
H17A0.66640.30301.02180.094*
H17B0.56930.39010.99600.094*
H17C0.71390.40790.99260.094*
C180.5666 (2)0.49042 (14)0.83534 (13)0.0561 (5)
H18A0.63900.52450.86380.084*
H18B0.49580.49920.86600.084*
H18C0.54670.51850.78040.084*
C190.40945 (14)0.38686 (11)0.65659 (9)0.0314 (3)
C200.30467 (14)0.32631 (11)0.67439 (9)0.0325 (4)
C210.29216 (16)0.22881 (12)0.70659 (10)0.0395 (4)
H210.36330.18910.72180.047*
C220.17413 (17)0.19248 (14)0.71551 (11)0.0455 (4)
H220.16590.12770.73680.055*
C230.06594 (17)0.25115 (15)0.69312 (12)0.0484 (4)
H23−0.01300.22490.70000.058*
C240.07467 (16)0.34710 (14)0.66114 (11)0.0438 (4)
H240.00280.38590.64580.053*
C250.19443 (15)0.38423 (12)0.65254 (9)0.0339 (4)
C260.36095 (14)0.47703 (11)0.62486 (9)0.0322 (3)
C270.14395 (17)0.55850 (14)0.59566 (12)0.0477 (4)
H27A0.08250.56540.63400.072*
H27B0.10180.54370.54100.072*
H27C0.19040.62060.59400.072*
C280.42723 (17)0.56692 (13)0.59485 (11)0.0440 (4)
H28A0.40490.62630.62400.066*
H28B0.40250.57560.53610.066*
H28C0.51690.55660.60510.066*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0508 (8)0.0427 (8)0.0313 (7)0.0060 (6)−0.0012 (6)−0.0044 (6)
N20.0330 (7)0.0350 (7)0.0386 (7)0.0063 (5)0.0018 (6)0.0039 (6)
O10.1152 (14)0.0747 (11)0.0624 (10)0.0308 (10)0.0278 (9)−0.0145 (8)
C10.0315 (8)0.0275 (8)0.0353 (8)−0.0008 (6)0.0018 (6)0.0037 (6)
C20.0382 (9)0.0299 (8)0.0324 (8)0.0016 (6)0.0052 (6)0.0063 (6)
C30.0371 (9)0.0382 (9)0.0457 (10)0.0028 (7)0.0058 (7)0.0039 (7)
C40.0499 (11)0.0477 (11)0.0557 (11)0.0115 (8)0.0177 (9)0.0075 (9)
C50.0758 (14)0.0434 (10)0.0417 (10)0.0161 (9)0.0160 (9)0.0026 (8)
C60.0690 (13)0.0507 (11)0.0416 (10)0.0012 (9)−0.0004 (9)−0.0076 (8)
C70.0432 (9)0.0474 (10)0.0390 (9)0.0005 (7)0.0012 (7)−0.0003 (8)
C80.173 (3)0.112 (2)0.0558 (15)0.059 (2)0.0022 (18)−0.0304 (16)
C90.0294 (7)0.0305 (8)0.0347 (8)0.0012 (6)−0.0007 (6)0.0008 (6)
C100.0281 (7)0.0323 (8)0.0339 (8)0.0007 (6)0.0008 (6)0.0018 (6)
C110.0414 (9)0.0336 (8)0.0366 (9)0.0005 (7)0.0037 (7)0.0017 (7)
C120.0446 (9)0.0316 (8)0.0514 (10)0.0054 (7)0.0089 (8)0.0044 (7)
C130.0410 (9)0.0411 (10)0.0516 (11)0.0064 (7)0.0047 (8)0.0156 (8)
C140.0398 (9)0.0508 (10)0.0366 (9)0.0029 (8)−0.0005 (7)0.0085 (8)
C150.0337 (8)0.0380 (9)0.0338 (8)0.0024 (7)0.0001 (6)0.0012 (7)
C160.0391 (9)0.0338 (9)0.0391 (9)0.0042 (7)0.0007 (7)−0.0020 (7)
C170.0839 (15)0.0651 (13)0.0362 (10)0.0102 (11)−0.0041 (10)−0.0105 (9)
C180.0727 (14)0.0391 (10)0.0550 (12)0.0119 (9)0.0018 (10)−0.0095 (9)
C190.0324 (8)0.0320 (8)0.0294 (8)0.0011 (6)0.0024 (6)0.0019 (6)
C200.0337 (8)0.0337 (8)0.0295 (8)0.0006 (6)0.0020 (6)0.0000 (6)
C210.0385 (9)0.0373 (9)0.0416 (9)−0.0008 (7)0.0011 (7)0.0051 (7)
C220.0453 (10)0.0423 (10)0.0485 (10)−0.0090 (8)0.0048 (8)0.0065 (8)
C230.0375 (9)0.0545 (11)0.0536 (11)−0.0099 (8)0.0079 (8)0.0008 (9)
C240.0338 (9)0.0490 (10)0.0481 (10)0.0024 (7)0.0030 (7)−0.0022 (8)
C250.0340 (8)0.0365 (8)0.0309 (8)0.0016 (6)0.0025 (6)−0.0013 (6)
C260.0335 (8)0.0326 (8)0.0305 (8)0.0023 (6)0.0036 (6)0.0012 (6)
C270.0435 (10)0.0446 (10)0.0535 (11)0.0141 (8)0.0003 (8)0.0048 (8)
C280.0461 (10)0.0368 (9)0.0492 (10)0.0022 (7)0.0069 (8)0.0103 (7)
Geometric parameters (Å, °) top
N1—C151.379 (2)C12—H120.9300
N1—C161.380 (2)C13—C141.373 (3)
N1—C171.450 (2)C13—H130.9300
N2—C251.381 (2)C14—C151.394 (2)
N2—C261.3867 (19)C14—H140.9300
N2—C271.457 (2)C16—C181.494 (2)
O1—C51.372 (2)C17—H17A0.9600
O1—C81.401 (4)C17—H17B0.9600
C1—C191.509 (2)C17—H17C0.9600
C1—C91.521 (2)C18—H18A0.9600
C1—C21.529 (2)C18—H18B0.9600
C1—H10.9800C18—H18C0.9600
C2—C71.375 (2)C19—C261.372 (2)
C2—C31.389 (2)C19—C201.432 (2)
C3—C41.374 (2)C20—C211.401 (2)
C3—H30.9300C20—C251.410 (2)
C4—C51.377 (3)C21—C221.371 (2)
C4—H40.9300C21—H210.9300
C5—C61.376 (3)C22—C231.400 (3)
C6—C71.395 (3)C22—H220.9300
C6—H60.9300C23—C241.376 (3)
C7—H70.9300C23—H230.9300
C8—H8A0.9600C24—C251.391 (2)
C8—H8B0.9600C24—H240.9300
C8—H8C0.9600C26—C281.493 (2)
C9—C161.366 (2)C27—H27A0.9600
C9—C101.440 (2)C27—H27B0.9600
C10—C111.408 (2)C27—H27C0.9600
C10—C151.413 (2)C28—H28A0.9600
C11—C121.376 (2)C28—H28B0.9600
C11—H110.9300C28—H28C0.9600
C12—C131.390 (3)
C15—N1—C16108.65 (13)N1—C15—C14129.36 (15)
C15—N1—C17125.05 (15)N1—C15—C10107.91 (13)
C16—N1—C17126.26 (15)C14—C15—C10122.72 (15)
C25—N2—C26108.65 (12)C9—C16—N1109.97 (14)
C25—N2—C27124.55 (14)C9—C16—C18129.17 (16)
C26—N2—C27126.80 (14)N1—C16—C18120.86 (15)
C5—O1—C8118.2 (2)N1—C17—H17A109.5
C19—C1—C9112.38 (12)N1—C17—H17B109.5
C19—C1—C2114.70 (13)H17A—C17—H17B109.5
C9—C1—C2112.06 (12)N1—C17—H17C109.5
C19—C1—H1105.6H17A—C17—H17C109.5
C9—C1—H1105.6H17B—C17—H17C109.5
C2—C1—H1105.6C16—C18—H18A109.5
C7—C2—C3117.22 (15)C16—C18—H18B109.5
C7—C2—C1123.63 (14)H18A—C18—H18B109.5
C3—C2—C1119.15 (14)C16—C18—H18C109.5
C4—C3—C2121.69 (17)H18A—C18—H18C109.5
C4—C3—H3119.2H18B—C18—H18C109.5
C2—C3—H3119.2C26—C19—C20107.00 (13)
C5—C4—C3120.34 (18)C26—C19—C1125.84 (14)
C5—C4—H4119.8C20—C19—C1127.15 (13)
C3—C4—H4119.8C21—C20—C25118.45 (14)
O1—C5—C4115.59 (19)C21—C20—C19134.46 (14)
O1—C5—C6125.1 (2)C25—C20—C19107.09 (13)
C4—C5—C6119.35 (17)C22—C21—C20119.45 (16)
C5—C6—C7119.62 (18)C22—C21—H21120.3
C5—C6—H6120.2C20—C21—H21120.3
C7—C6—H6120.2C21—C22—C23121.13 (17)
C2—C7—C6121.77 (17)C21—C22—H22119.4
C2—C7—H7119.1C23—C22—H22119.4
C6—C7—H7119.1C24—C23—C22120.98 (16)
O1—C8—H8A109.5C24—C23—H23119.5
O1—C8—H8B109.5C22—C23—H23119.5
H8A—C8—H8B109.5C23—C24—C25117.91 (16)
O1—C8—H8C109.5C23—C24—H24121.0
H8A—C8—H8C109.5C25—C24—H24121.0
H8B—C8—H8C109.5N2—C25—C24130.18 (15)
C16—C9—C10106.89 (13)N2—C25—C20107.76 (13)
C16—C9—C1123.61 (14)C24—C25—C20122.07 (15)
C10—C9—C1129.50 (14)C19—C26—N2109.49 (13)
C11—C10—C15117.53 (14)C19—C26—C28129.77 (14)
C11—C10—C9135.90 (15)N2—C26—C28120.74 (13)
C15—C10—C9106.57 (13)N2—C27—H27A109.5
C12—C11—C10119.50 (15)N2—C27—H27B109.5
C12—C11—H11120.2H27A—C27—H27B109.5
C10—C11—H11120.2N2—C27—H27C109.5
C11—C12—C13121.45 (16)H27A—C27—H27C109.5
C11—C12—H12119.3H27B—C27—H27C109.5
C13—C12—H12119.3C26—C28—H28A109.5
C14—C13—C12121.14 (16)C26—C28—H28B109.5
C14—C13—H13119.4H28A—C28—H28B109.5
C12—C13—H13119.4C26—C28—H28C109.5
C13—C14—C15117.65 (16)H28A—C28—H28C109.5
C13—C14—H14121.2H28B—C28—H28C109.5
C15—C14—H14121.2
Acknowledgements top

The work was supported by the National Natural Science Foundation of China (grant No. 20376071).

references
References top

Azizian, J., Teimouri, F. & Mohammadizadeh, M. R. (2007). Catal. Commun. 8, 1117–1121.

Bruker (2004). SMART and SAINT. Bruker AXS Inc., Madison, Winsonsin, USA.

Chang, Y. C., Riby, J., Grace, H. F., Peng, G. F. & Bieldanes, L. F. (1999). Biochem. Pharmacol. 58, 825–834.

Deb, M. L. & Bhuyan, P. J. (2006). Tetrahedron Lett. 47, 1441–1443.

Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.

Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837–838.

Ge, X., Fares, F. A. & Fares, S. Y. (1999). Anticancer Res. 19, 3199–3203.

Morris, S. A. & Andersen, R. J. (1990). Tetrahedron, 46, 715–720.

Osawa, T. & Namiki, M. (1983). Tetrahedron Lett. 24, 4719–4722.

Poter, J. K., Bacon, C. W., Robins, J. D., Himmelsbach, D. S. & Higman, H. C. (1977). J. Agric. Food Chem. 25, 88–93.

Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122.

Sundberg, R. J. (1996). The Chemistry of Indoles, p. 113. New York: Academic Press.