PMCCPMCCPMCC

Search tips
Search criteria 

Advanced

 
Logo of actaeInternational Union of Crystallographysearchopen accessarticle submissionjournal home pagethis article
 
Acta Crystallogr Sect E Struct Rep Online. 2010 October 1; 66(Pt 10): o2525–o2526.
Published online 2010 September 11. doi:  10.1107/S1600536810034641
PMCID: PMC2983143

(E)-1-(2,4,6-Trimeth­oxy­phen­yl)pent-1-en-3-one

Abstract

The title compound, C14H18O4, was obtained unintentionally as the major product of an attempted synthesis of (E,E)-2,5-bis­[2-(2,4,6-trimeth­oxy­phen­yl)ethen­yl]pyrazine. The crystal packing features layers based on two weak C—H(...)O hydrogen bonds involving the O atom of the carbonyl group and two Ometh­oxy(...)Cmeth­oxy inter­actions [3.109 (2) Å]. The sheets are inter­connected via meth­oxy–meth­oxy dimers and C—H(...)π inter­actions.

Related literature

For related compounds containing the Ph—CH=CH—CO— fragment, see: Zhang et al. (2008 [triangle]); Degen & Bolte (1999 [triangle]); Zonouzi et al. (2009 [triangle]); Wang et al. (2005 [triangle]). For π-bridged donor–acceptor–donor systems as candidates for organic light-emitting diodes and their non-linear optical properties, see Liu et al. (2001 [triangle]); Grimsdale et al. (1997 [triangle]); Chemla (1987 [triangle]). For a description of the Cambridge Structural Database, see: Allen (2002 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-o2525-scheme1.jpg

Experimental

Crystal data

  • C14H18O4
  • M r = 250.28
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o2525-efi1.jpg
  • a = 6.8626 (8) Å
  • b = 8.297 (1) Å
  • c = 12.068 (2) Å
  • α = 71.96 (1)°
  • β = 84.28 (1)°
  • γ = 84.90 (1)°
  • V = 648.88 (15) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 0.09 mm−1
  • T = 293 K
  • 0.3 × 0.24 × 0.18 mm

Data collection

  • Enraf–Nonius CAD-4 diffractometer
  • 4732 measured reflections
  • 2366 independent reflections
  • 1589 reflections with > 2/s(I)
  • R int = 0.020
  • 3 standard reflections every 60 min intensity decay: none

Refinement

  • R[F 2 > 2σ(F 2)] = 0.037
  • wR(F 2) = 0.106
  • S = 1.03
  • 2366 reflections
  • 166 parameters
  • H-atom parameters constrained
  • Δρmax = 0.14 e Å−3
  • Δρmin = −0.17 e Å−3

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994 [triangle]); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1996 [triangle]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 [triangle]); software used to prepare material for publication: WinGX (Farrugia, 1999 [triangle]), Mercury (Macrae et al., 2008 [triangle]) and PLATON (Spek, 2009 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810034641/zl2296sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810034641/zl2296Isup2.hkl

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

Acknowledgments

AC wishes to thank the Institute for the Promotion of Innovation by Science and Technology in Flanders (IWT) for a predoctoral grant. Financial support by the University of Antwerp under grant No. GOA-2404 is gratefully acknowledged.

supplementary crystallographic information

Comment

π-Bridged donor-acceptor-donor (A—D—A) systems are promising candidates for electronic applications such as organic light-emitting diodes (Liu et al., 2001; Grimsdale et al., 1997), as they are expected to have electronic properties similar to those of conventional OPV-type systems but with a red-shifted emission spectrum. Moreover, due to their high degree of conjugation, these A—D—A oligomers are also excellent candidates for organic non-linear optic (NLO) media with a high second-order hyperpolarizability, γ (Chemla, 1987). In an attempt to synthesize the A—D—A system E,E-2,5-bis[2-(2,4,6-trimethoxyphenyl)ethenyl]pyrazine from dimethylpyrazine and the relevant benzaldehyde under standard condensation conditions, (E)-1-(2,4,6-trimethoxyphenyl)pent-1-en-3-one (Fig. 1) was obtained as the major product. In this compound the C=C bond is not disordered, in contrast to what is the case in the 3-methoxy-4-acetoxyphenyl derivative YODGOO (Zhang et al., 2008) and the molecule adopts the anti conformation indicating that there are no energetically beneficial intermolecular contacts favouring the syn conformation as in the unsubstituted DIBNEH (Degen & Bolte, 1999). The title compound displays two weak intramolecular hydrogen bonds involving the methoxy groups in the ortho positions of the phenyl ring, one in a five- and one in a six-membered ring configuration. In contrast, in the 2-hydroxy-5-bromophenyl derivative NORGOR (Zonouzi et al., 2009) a less stable six-membered ring configuration is observed due to the competing strong intermolecular O—H···O hydrogen bond with an adjacent molecule. In the 2-hydroxyphenyl derivative FONKEZ (Wang et al., 2005), the more favourable five-membered ring configuration is also seen. The packing of the title compound is determined in first instance by contacts between the methoxy groups. Two molecules (symmetry-related via an inversion centre) are connected into a dimer involving O2 and C11 of the methoxy groups in the 2- and 4-positions [C11···O2i, 3.109 (2) Å, 178.33 (12)°, symm. code i = 1 - x, -y, 1 - z] (Fig. 2); note that the C···O—C angle is almost linear. Sheets are then generated through two weak hydrogen bonds involving H5 (Table 1, entry 1) and H31C (entry 2) contacting the oxygen atom of the carbonyl group (O4). These sheets are then interconnected by four additional weak hydrogen bonds (Fig. 3): H21C and O2 are involved in a second dimer formation (entry 3), H11A and H12C contact the oxygen atom of the carbonyl (O4, entries 4 and 5) and H10B of the methylene group next to the carbonyl group generates a CH···π interaction with a nearby phenyl ring (entry 6).

Experimental

A solution of sodium (1.0 g, 0.04 mol) in ethanol (50 ml) was added dropwise to a solution of 2,4,6-trimethoxybenzaldehyde (5.6 g, 0.04 mol) and 2,5-dimethylpyrazine (2.2 g, 0.02 mol) in ethanol (150 ml) at room temperature and the reaction mixture was heated under reflux for 4 h. The resulting fluorescent yellow solution was poured into 500 ml of ice water and the precipitate was filtered off and isomerized to the all-E form in p-xylene with a catalytic amount of iodine. Crystals suitable for X-ray diffraction were grown by slow evaporation of a THF solution. The yield was 2.3 g (46%). M.p. (uncorrected) 401 K. 1H NMR (CDCl3, 400 MHz, TMS): δ 7.63 (td, 8 and 0.4 Hz, H5), 8.18 (ddd, 8, 2 and 1 Hz, H6), 8.27 (ddd, 8, 2 and 1 Hz, H4), 8.62 (td, 2 and 0.4 Hz, H2), H4 and H6 appear to be magnetically equivalent. 13C NMR (CDCl3, 100 MHz, TMS): δ 121.59 (C2), 124.54 (C5), 130.24 (C6), 132.32 (C4), 142.46 (C1), 148.53 (C3).

Refinement

Hydrogen atoms were placed in calculated positions and refined as riding with C—H distances of 0.93 Å.

Figures

Fig. 1.
: Molecular structure of the title compound showing the numbering scheme. Displacement ellipsoids are drawn at the 50% probability level; hydrogen atoms are represented by spheres with an arbitrary radius.
Fig. 2.
: Sheets formed by weak hydrogen bonds and Omethoxy···Cmethoxy interactions.
Fig. 3.
: Interactions responsible for the stabilization of the crystal packing in the direction perpendicular to the the generated sheets.

Crystal data

C14H18O4Z = 2
Mr = 250.28F(000) = 268
Triclinic, P1Dx = 1.281 Mg m3
Hall symbol: -P 1Melting point: 401 K
a = 6.8626 (8) ÅMo Kα radiation, λ = 0.71073 Å
b = 8.297 (1) ÅCell parameters from 25 reflections
c = 12.068 (2) Åθ = 5.8–10.7°
α = 71.96 (1)°µ = 0.09 mm1
β = 84.28 (1)°T = 293 K
γ = 84.90 (1)°Prism, yellow
V = 648.88 (15) Å30.3 × 0.24 × 0.18 mm

Data collection

Enraf–Nonius CAD-4 diffractometerRint = 0.020
Radiation source: fine-focus sealed tubeθmax = 25.3°, θmin = 1.8°
graphiteh = −8→8
non–profiled ω/2θ scansk = −9→9
4732 measured reflectionsl = −14→14
2366 independent reflections3 standard reflections every 60 min
1589 reflections with > 2/s(I) intensity decay: none

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.037Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.106H-atom parameters constrained
S = 1.02w = 1/[σ2(Fo2) + (0.0495P)2 + 0.1212P] where P = (Fo2 + 2Fc2)/3
2366 reflections(Δ/σ)max < 0.001
166 parametersΔρmax = 0.14 e Å3
0 restraintsΔρmin = −0.17 e Å3

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
C121.6553 (3)−0.2420 (2)0.97422 (19)0.0572 (5)
H12A1.6978−0.18671.02590.086*
H12B1.7585−0.24530.91490.086*
H12C1.6235−0.35581.01790.086*
O20.41445 (17)0.31488 (16)0.60482 (12)0.0544 (4)
O10.90913 (18)−0.12493 (15)0.63577 (11)0.0498 (3)
O30.95452 (17)0.26141 (15)0.84353 (11)0.0508 (4)
C20.8301 (2)0.0153 (2)0.66303 (15)0.0389 (4)
C10.9334 (2)0.0684 (2)0.73980 (14)0.0373 (4)
O41.4852 (2)−0.34752 (17)0.81476 (13)0.0675 (4)
C30.6593 (2)0.1019 (2)0.61907 (15)0.0434 (4)
H30.59420.06570.56790.052*
C71.1125 (2)−0.0161 (2)0.79054 (14)0.0383 (4)
H71.16070.03230.84140.046*
C60.8527 (2)0.2139 (2)0.76858 (14)0.0375 (4)
C81.2193 (2)−0.1515 (2)0.77646 (16)0.0440 (4)
H81.1771−0.20420.72620.053*
C50.6805 (2)0.3019 (2)0.72569 (15)0.0405 (4)
H50.63070.39750.74620.049*
C91.3985 (2)−0.2232 (2)0.83457 (15)0.0414 (4)
C210.3216 (3)0.4540 (3)0.63919 (19)0.0590 (5)
H21A0.29560.42000.72260.088*
H21B0.20030.48910.60270.088*
H21C0.40610.54690.61550.088*
C101.4756 (3)−0.1447 (2)0.91735 (15)0.0427 (4)
H10A1.3731−0.13950.97780.051*
H10B1.5081−0.02920.87480.051*
C40.5856 (2)0.2428 (2)0.65167 (15)0.0408 (4)
C310.8968 (3)0.4174 (2)0.86731 (18)0.0548 (5)
H31A0.89840.50880.79530.082*
H31B0.98630.43710.91740.082*
H31C0.76670.41150.90530.082*
C110.8077 (3)−0.1881 (2)0.56160 (17)0.0535 (5)
H11A0.6802−0.21980.59820.080*
H11B0.8809−0.28560.54860.080*
H11C0.7938−0.10150.48820.080*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C120.0540 (12)0.0567 (12)0.0682 (13)0.0125 (9)−0.0247 (10)−0.0277 (10)
O20.0432 (7)0.0571 (8)0.0729 (9)0.0161 (6)−0.0281 (6)−0.0321 (7)
O10.0480 (7)0.0507 (7)0.0651 (8)0.0121 (6)−0.0228 (6)−0.0368 (7)
O30.0475 (7)0.0496 (7)0.0707 (9)0.0177 (6)−0.0281 (6)−0.0391 (7)
C20.0383 (9)0.0378 (9)0.0456 (10)0.0026 (7)−0.0072 (7)−0.0201 (8)
C10.0339 (9)0.0384 (9)0.0434 (10)0.0034 (7)−0.0085 (7)−0.0177 (8)
O40.0663 (9)0.0600 (9)0.0944 (11)0.0310 (7)−0.0347 (8)−0.0504 (8)
C30.0412 (10)0.0478 (10)0.0495 (11)0.0017 (8)−0.0167 (8)−0.0241 (9)
C70.0358 (9)0.0394 (9)0.0452 (10)0.0036 (7)−0.0106 (7)−0.0199 (8)
C60.0355 (9)0.0389 (9)0.0431 (9)0.0025 (7)−0.0095 (7)−0.0190 (8)
C80.0435 (10)0.0436 (10)0.0538 (11)0.0070 (8)−0.0168 (8)−0.0261 (9)
C50.0385 (9)0.0364 (9)0.0498 (10)0.0063 (7)−0.0096 (8)−0.0181 (8)
C90.0405 (9)0.0371 (9)0.0497 (11)0.0073 (8)−0.0087 (8)−0.0190 (8)
C210.0445 (11)0.0633 (13)0.0740 (14)0.0208 (9)−0.0200 (10)−0.0298 (11)
C100.0436 (10)0.0390 (9)0.0485 (10)0.0055 (8)−0.0107 (8)−0.0175 (8)
C40.0330 (9)0.0431 (10)0.0463 (10)0.0042 (7)−0.0098 (8)−0.0132 (8)
C310.0526 (11)0.0507 (11)0.0773 (14)0.0156 (9)−0.0255 (10)−0.0415 (11)
C110.0562 (11)0.0568 (12)0.0629 (12)0.0039 (9)−0.0177 (9)−0.0385 (10)

Geometric parameters (Å, °)

C12—C101.514 (2)C7—H70.9300
C12—H12A0.9600C6—C51.390 (2)
C12—H12B0.9600C8—C91.463 (2)
C12—H12C0.9600C8—H80.9300
O2—C41.3620 (19)C5—C41.381 (2)
O2—C211.423 (2)C5—H50.9300
O1—C21.3584 (19)C9—C101.508 (2)
O1—C111.4287 (19)C21—H21A0.9600
O3—C61.3629 (19)C21—H21B0.9600
O3—C311.4253 (19)C21—H21C0.9600
C2—C31.382 (2)C10—H10A0.9700
C2—C11.412 (2)C10—H10B0.9700
C1—C61.409 (2)C31—H31A0.9600
C1—C71.452 (2)C31—H31B0.9600
O4—C91.2206 (19)C31—H31C0.9600
C3—C41.385 (2)C11—H11A0.9600
C3—H30.9300C11—H11B0.9600
C7—C81.332 (2)C11—H11C0.9600
C10—C12—H12A109.5O4—C9—C8118.99 (15)
C10—C12—H12B109.5O4—C9—C10120.39 (15)
H12A—C12—H12B109.5C8—C9—C10120.62 (14)
C10—C12—H12C109.5O2—C21—H21A109.5
H12A—C12—H12C109.5O2—C21—H21B109.5
H12B—C12—H12C109.5H21A—C21—H21B109.5
C4—O2—C21118.09 (13)O2—C21—H21C109.5
C2—O1—C11118.44 (13)H21A—C21—H21C109.5
C6—O3—C31119.00 (12)H21B—C21—H21C109.5
O1—C2—C3122.66 (14)C9—C10—C12113.02 (14)
O1—C2—C1115.88 (14)C9—C10—H10A109.0
C3—C2—C1121.46 (14)C12—C10—H10A109.0
C6—C1—C2116.34 (14)C9—C10—H10B109.0
C6—C1—C7118.79 (15)C12—C10—H10B109.0
C2—C1—C7124.87 (14)H10A—C10—H10B107.8
C2—C3—C4119.62 (15)O2—C4—C5124.12 (15)
C2—C3—H3120.2O2—C4—C3114.18 (14)
C4—C3—H3120.2C5—C4—C3121.69 (15)
C8—C7—C1130.83 (16)O3—C31—H31A109.5
C8—C7—H7114.6O3—C31—H31B109.5
C1—C7—H7114.6H31A—C31—H31B109.5
O3—C6—C5121.97 (14)O3—C31—H31C109.5
O3—C6—C1115.08 (13)H31A—C31—H31C109.5
C5—C6—C1122.94 (14)H31B—C31—H31C109.5
C7—C8—C9124.60 (15)O1—C11—H11A109.5
C7—C8—H8117.7O1—C11—H11B109.5
C9—C8—H8117.7H11A—C11—H11B109.5
C4—C5—C6117.93 (15)O1—C11—H11C109.5
C4—C5—H5121.0H11A—C11—H11C109.5
C6—C5—H5121.0H11B—C11—H11C109.5
C11—O1—C2—C3−2.0 (2)C7—C1—C6—C5−179.07 (16)
C11—O1—C2—C1177.92 (16)C1—C7—C8—C9−179.80 (17)
O1—C2—C1—C6179.96 (15)O3—C6—C5—C4−178.96 (16)
C3—C2—C1—C6−0.1 (2)C1—C6—C5—C40.0 (3)
O1—C2—C1—C7−0.5 (3)C7—C8—C9—O4−179.72 (18)
C3—C2—C1—C7179.42 (17)C7—C8—C9—C100.1 (3)
O1—C2—C3—C4179.20 (16)O4—C9—C10—C12−3.5 (3)
C1—C2—C3—C4−0.8 (3)C8—C9—C10—C12176.69 (17)
C6—C1—C7—C8−178.60 (19)C21—O2—C4—C5−3.7 (3)
C2—C1—C7—C81.9 (3)C21—O2—C4—C3176.19 (16)
C31—O3—C6—C5−7.9 (3)C6—C5—C4—O2178.94 (16)
C31—O3—C6—C1173.02 (16)C6—C5—C4—C3−0.9 (3)
C2—C1—C6—O3179.50 (15)C2—C3—C4—O2−178.58 (16)
C7—C1—C6—O30.0 (2)C2—C3—C4—C51.3 (3)
C2—C1—C6—C50.5 (3)

Hydrogen-bond geometry (Å, °)

Cg is the centroid of the C1–C6 ring.
D—H···AD—HH···AD···AD—H···A
C5—H5···O4i0.932.593.517 (2)177
C31—H31C···O4i0.962.703.286 (2)120
C21—H21C···O2ii0.962.763.419 (2)127
C11—H11A···O4iii0.962.753.557 (2)142
C12—H12C···O4iv0.962.763.706 (2)167
C10—H10B···Cgv0.972.773.59142

Symmetry codes: (i) x−1, y+1, z; (ii) −x+1, −y+1, −z+1; (iii) x−1, y, z; (iv) −x+3, −y−1, −z+2; (v) x+1, y, z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: ZL2296).

References

  • Allen, F. H. (2002). Acta Cryst. B58, 380–388. [PubMed]
  • Chemla, D. S. (1987). Nonlinear Optical Properties of Organic Molecules and Crystals Boston: Academic Press.
  • Degen, A. & Bolte, M. (1999). Acta Cryst. C55, IUC9900170.
  • Enraf–Nonius (1994). CAD-4 EXPRESS Enraf–Nonius, Delft, The Netherlands.
  • Farrugia, L. J. (1997). J. Appl. Cryst.30, 565.
  • Farrugia, L. J. (1999). J. Appl. Cryst.32, 837–838.
  • Grimsdale, A. C., Cervini, R., Friend, R. H., Holmes, A. B., Kim, S. T. & Moratti, S. C. (1997). Synth. Met.85, 1257–1258.
  • Harms, K. & Wocadlo, S. (1996). XCAD4 University of Marburg, Germany.
  • Liu, M. W., Zhang, X. H., Lai, W. Y., Lin, X. Q., Wong, F. L., Gao, Z. Q., Lee, C. S., Hung, L. S., Lee, S. T. & Kwong, H. L. (2001). Phys. Status Solidi A: Appl. Res.185, 203–211.
  • Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst.41, 466–470.
  • Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. [PubMed]
  • Spek, A. L. (2009). Acta Cryst. D65, 148–155. [PMC free article] [PubMed]
  • Wang, S.-F., Ruan, B.-F., Li, H.-Q. & Zhu, H.-L. (2005). Acta Cryst. E61, o1697–o1698.
  • Zhang, H., Li, S. & Shi, X. (2008). Acta Cryst. E64, o1507. [PMC free article] [PubMed]
  • Zonouzi, A., Izakiana, Z., Rahmani, H. & Ng, S. W. (2009). Acta Cryst. E65, o795. [PMC free article] [PubMed]

Articles from Acta Crystallographica Section E: Structure Reports Online are provided here courtesy of International Union of Crystallography