(E)-2-{3-[4-(Diphenyl­amino)styr­yl]-5,5-dimethyl­cyclo­hex-2-enyl­idene}­malono­nitrile

Hai-Dong Ju; Xu-Tang Tao; Shi-Qing Xu; Wen-Tao Yu

doi:10.1107/S1600536809014378

. 2009 Apr 25;65(Pt 5):o1135. doi: 10.1107/S1600536809014378

(E)-2-{3-[4-(Diphenylamino)styryl]-5,5-dimethylcyclohex-2-enylidene}malononitrile

Hai-Dong Ju ^a,^*, Xu-Tang Tao ^b, Shi-Qing Xu ^a, Wen-Tao Yu ^b

PMCID: PMC2977807 PMID: 21583944

Abstract

In the title compound, C₃₁H₂₇N₃, the cyclohexene ring has an envelope configuration. In the crystal structure, there is an 34 Å³ void around the inversion center, but the low electron density (0.13 e Å⁻³) in the difference Fourier map suggests no solvent molecule occupying this void. No hydrogen bonding is found in the crystal structure.

Related literature

For background to organic compounds with light emitting properties, see: Tang et al. (1998 ▶); Li et al. (2003 ▶); Hye et al. (2004 ▶). For the synthesis, see: Lemke (1974 ▶); Tao & Miyata (2001 ▶). For related crystal structures, see: Kia et al. (2009 ▶); Ju et al. (2006 ▶).

Experimental

Crystal data

C₃₁H₂₇N₃
M _r = 441.56
Monoclinic,
a = 13.239 (5) Å
b = 16.757 (8) Å
c = 11.886 (3) Å
β = 104.073 (5)°
V = 2557.7 (17) Å³
Z = 4
Mo Kα radiation
μ = 0.07 mm⁻¹
T = 293 K
0.48 × 0.19 × 0.16 mm

Data collection

Bruker SMART area-detector diffractometer
Absorption correction: none
20681 measured reflections
5879 independent reflections
3554 reflections with I > 2σ(I)
R _int = 0.027

Refinement

R[F ² > 2σ(F ²)] = 0.046
wR(F ²) = 0.167
S = 0.92
5879 reflections
309 parameters
H-atom parameters constrained
Δρ_max = 0.13 e Å⁻³
Δρ_min = −0.18 e Å⁻³

Data collection: SMART (Bruker, 2002 ▶); cell refinement: SAINT (Bruker, 2002 ▶); data reduction: SAINT; 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 ▶).

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809014378/xu2505sup1.cif

e-65-o1135-sup1.cif^{(23.2KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809014378/xu2505Isup2.hkl

e-65-o1135-Isup2.hkl^{(287.9KB, hkl)}

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

Acknowledgments

This work was financially supported by the National Natural Science Foundation of China (grant Nos. 50590403, 50402018 and 50603011).

supplementary crystallographic information

Comment

The organic compounds with donor-π-acceptor (D-π-A) structure have special light-emitting properties, and show potential application in organic light-emitting diodes (Tang et al., 1998; Hye et al., 2004). However, these molecules easily aggregate, which usually reduces their fluorescence intensity (Li et al., 2003). Therefore, it is important to study their intermolecular interaction in the solid state. Recently we synthesized the title compound and studied its crystal structure.

The molecular structure is shown in Fig. 1. Three benzenes of triphenyl amine group show a three-bladed propeller configuration due to repulsion force. The bond lengths of C13—N1 are shorter than the single C—N distance (1.47–1.50 Å) and longer than double C=N bond distance (1.34–1.38 Å), which is due to the conjugation of p-π in triphenyl amine group. Because of long conjugation length, all atoms are roughly coplanar (Kia et al., 2009). However, the cyclohexene group shows an envelope configuration due to its ring tension, which atoms are partly out of the plane (Ju et al., 2006). The triphenyl amine and cyclohexene groups could hold back farther gather of these molecules in the solid state, which is due to their non-coplanar conjugation. No hydrogen bonding is found in the crystal structure (Fig. 2).

Experimental

Hexahydropyridine (1 ml) and acetic acid (2 ml) were respectively added dropwise to a stirred benzene (100 ml) solution with 4-diphenylamino-benzaldehyde (1.1 g, 4 mmol) and 2-(3,5,5-Trimethylcyclohex-2-enylidene)-malononitrile (0.92 g, 5 mmol). The mixture was stirred at room temperature for 1 h, then separated water at refluxing temperature for another 5 h. Cooled to room temperature, the title compound was gotten (Lemke, 1974; Tao & Miyata, 2001). Single crystal suitable for X-ray diffraction analysis were obtained by slow evaporation of its ethanol saturated solution at room temperature.