organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890

Hexyl (E)-3-(3,4-dihy­dr­oxy­phen­yl)acrylate

aSchool of Biological and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212018, People's Republic of China, and bSericultural Research Institute, Chinese Academy of Agricultural Sciences, Zhenjiang 212018, People's Republic of China
*Correspondence e-mail: fuword@163.com

(Received 13 October 2011; accepted 30 November 2011; online 10 December 2011)

The title mol­ecule, C15H20O4, has an E conformation about its C=C bond and is almost planar (r.m.s. deviation of all non-H atoms = 0.04 Å). The crystal structurere features O—H⋯O and C—H⋯O hydrogen bonds.

Related literature

For general background to caffeic acid and its derivatives, see: Buzzi et al. (2009[Buzzi, F. de C., Franzoi, C. L., Antonini, G., Fracasso, M., Filho, V. C., Yunes, R. A. & Niero, R. (2009). Eur. J. Med. Chem. 44, 4596-4602.]); Uwai et al. (2008[Uwai, K., Osanai, Y., Imaizumi, T., Kanno, S., Takeshita, M. & Ishikawa, M. (2008). Bioorg. Med. Chem. 16, 7795-7803.]). For details of the synthesis, see: Feng et al. (2011[Feng, Y., Zhang, A., Li, J. & He, B. (2011). Bioresource Technol. 102, 3607-3609.]); Son et al. (2011[Son, S. M., Kimura, H. & Kusakabe, K. (2011). Bioresource Technol. 102, 2130-2132.]). For related structures, see: Xia et al. (2004[Xia, C.-N., Hu, W.-X. & Rao, G.-W. (2004). Acta Cryst. E60, o913-o914.], 2006[Xia, C.-N., Hu, W.-X. & Zhou, W. (2006). Acta Cryst. E62, o3900-o3901.]). For standard bond lengths, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]).

[Scheme 1]

Experimental

Crystal data
  • C15H20O4

  • Mr = 264.31

  • Triclinic, [P \overline 1]

  • a = 5.2920 (11) Å

  • b = 10.689 (2) Å

  • c = 12.732 (3) Å

  • α = 95.45 (3)°

  • β = 92.76 (3)°

  • γ = 96.84 (3)°

  • V = 710.6 (2) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 293 K

  • 0.20 × 0.10 × 0.10 mm

Data collection
  • Enraf–Nonius CAD-4 diffractometer

  • Absorption correction: ψ scan (North et al., 1968[North, A. C. T., Phillips, D. C. & Mathews, F. S. (1968). Acta Cryst. A24, 351-359.]) Tmin = 0.983, Tmax = 0.991

  • 2912 measured reflections

  • 2608 independent reflections

  • 1515 reflections with I > 2σ(I)

  • Rint = 0.022

  • 3 standard reflections every 200 reflections intensity decay: 1%

Refinement
  • R[F2 > 2σ(F2)] = 0.061

  • wR(F2) = 0.178

  • S = 1.00

  • 2608 reflections

  • 172 parameters

  • H-atom parameters constrained

  • Δρmax = 0.19 e Å−3

  • Δρmin = −0.28 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1A⋯O2i 0.85 2.07 2.857 (2) 154
O2—H2A⋯O3ii 0.82 1.97 2.786 (3) 173
C5—H5A⋯O3ii 0.93 2.54 3.243 (3) 133
Symmetry codes: (i) -x+1, -y, -z+1; (ii) -x, -y+1, -z+1.

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994[Enraf-Nonius (1994). CAD-4 EXPRESS. Enraf-Nonius, Delft, The Netherlands.]); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995[Harms, K. & Wocadlo, S. (1995). XCAD4. University of Marburg, Germany.]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Caffeic acid and its derivatives are widely distributed in medicinal plants and are therefore present in human plasma in a diet dependent concentration. These compounds are known to show a variety of biological effects such as anti-tumor, anti-oxidant, and anti-inflammatory activities (Uwai et al., 2008; Buzzi et al., 2009). In order to investigate their properties better, we synthesize a series of caffeic acid esters. The title compound, hexyl (E)-3-(3,4-dihydroxyphenyl)acrylate (I) was obtained earlier (Feng et al., 2011; Son et al., 2011). We report herein the crystal structure of the title compound.

The molecule of (I) has an E configuration (Fig. 1). All non-H atoms of (I) are almost coplanar, with a root mean square deviation from the least-squares plane of 0.04 A°. The bond lengths and angles are within normal ranges (Allen et al., 1987), they are in very good agreement with those found in similar caffeic acid structures (Xia et al., 2004; Xia et al., 2006)

In the crystal structure, intermolecular O—H···O interactions (Table 1) link the molecules into ribbons parallel to the (112) plane (Fig. 2), this may be effective in the stabilization of the structure. On the other hand, the intramolecular O—H···O H-bond also contribute to the stability of the molecular configuration (Table 1).

Related literature top

For general background to caffeic acid and its derivatives, see: Buzzi et al. (2009); Uwai et al. (2008). For details of the synthesis, see: Feng et al. (2011); Son et al. (2011). For related structures, see: Xia et al. (2004, 2006). For standard bond lengths, see: Allen et al. (1987).

Experimental top

Esterification of caffeic acid with hexyl alcohol was performed in a column (inner diameter = 15 mm, length = 200 mm). Cation exchange resin CD-552 particles (5 g), molecular sieve (5 g) and glass beads of 2 mm in diameter were packed into the middle of the reactor. In a reaction mixture tank, caffeic acid (8.95 g) was mixed with 100 ml of hexyl alcohol. The reaction mixture was supplied to the reaction column at 10.0 ml/h. The reaction continued at 90°C for 24 h. The mixture was evaporated to dryness and followed by the addition of ethanol and extracted with dichloromethane three times. The dichloromethane extract was evaporated to give a solid residue. The residue was recrystallized from ethanol/petroleum ether (1:1) to give the title compound as brown crystals (4.9 g, 54.7%).

Refinement top

The H atoms were placed in calculated positions (O—H = 0.82 A ° and C—H = 0.93–0.97 A °) and constrained to ride on their parent atoms, with Uiso(H) = 1.2 or 1.5Ueq(C, O).

Computing details top

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994); cell refinement: CAD-4 EXPRESS (Enraf–Nonius, 1994); data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title molecule, with the atom numbering scheme. Thermal displacement ellipsoids are drawn at 30% probability level.
[Figure 2] Fig. 2. A partial packing diagram. Hydrogen bonds are shown as dashed lines.
Hexyl (E)-3-(3,4-dihydroxyphenyl)acrylate top
Crystal data top
C15H20O4Z = 2
Mr = 264.31F(000) = 284
Triclinic, P1Dx = 1.235 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 5.2920 (11) ÅCell parameters from 25 reflections
b = 10.689 (2) Åθ = 9–13°
c = 12.732 (3) ŵ = 0.09 mm1
α = 95.45 (3)°T = 293 K
β = 92.76 (3)°Block, brown
γ = 96.84 (3)°0.20 × 0.10 × 0.10 mm
V = 710.6 (2) Å3
Data collection top
Enraf–Nonius CAD-4
diffractometer
1515 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.022
Graphite monochromatorθmax = 25.4°, θmin = 1.6°
ω/2θ scansh = 06
Absorption correction: ψ scan
(North et al., 1968)
k = 1212
Tmin = 0.983, Tmax = 0.991l = 1515
2912 measured reflections3 standard reflections every 200 reflections
2608 independent reflections intensity decay: 1%
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.061Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.178H-atom parameters constrained
S = 1.00 w = 1/[σ2(Fo2) + (0.085P)2 + 0.096P]
where P = (Fo2 + 2Fc2)/3
2608 reflections(Δ/σ)max < 0.001
172 parametersΔρmax = 0.19 e Å3
0 restraintsΔρmin = 0.28 e Å3
Crystal data top
C15H20O4γ = 96.84 (3)°
Mr = 264.31V = 710.6 (2) Å3
Triclinic, P1Z = 2
a = 5.2920 (11) ÅMo Kα radiation
b = 10.689 (2) ŵ = 0.09 mm1
c = 12.732 (3) ÅT = 293 K
α = 95.45 (3)°0.20 × 0.10 × 0.10 mm
β = 92.76 (3)°
Data collection top
Enraf–Nonius CAD-4
diffractometer
1515 reflections with I > 2σ(I)
Absorption correction: ψ scan
(North et al., 1968)
Rint = 0.022
Tmin = 0.983, Tmax = 0.9913 standard reflections every 200 reflections
2912 measured reflections intensity decay: 1%
2608 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0610 restraints
wR(F2) = 0.178H-atom parameters constrained
S = 1.00Δρmax = 0.19 e Å3
2608 reflectionsΔρmin = 0.28 e Å3
172 parameters
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
O10.7392 (4)0.09426 (17)0.38828 (16)0.0649 (6)
H1A0.68810.04080.43040.078*
C10.5906 (5)0.3938 (2)0.3065 (2)0.0504 (7)
H1B0.64960.45080.25970.060*
O20.3463 (4)0.13532 (16)0.51361 (14)0.0564 (6)
H2A0.23940.16170.55160.085*
C20.7038 (5)0.2853 (2)0.3144 (2)0.0528 (8)
H2B0.83900.27000.27300.063*
C30.6192 (5)0.1991 (2)0.3832 (2)0.0463 (7)
O30.0120 (4)0.75695 (18)0.36537 (16)0.0685 (7)
O40.2768 (4)0.81988 (16)0.24479 (15)0.0571 (6)
C40.4190 (5)0.2232 (2)0.4456 (2)0.0434 (7)
C50.3053 (5)0.3312 (2)0.43703 (19)0.0440 (7)
H5A0.16960.34620.47830.053*
C60.3883 (5)0.4188 (2)0.36794 (19)0.0420 (6)
C70.2635 (5)0.5329 (2)0.36356 (19)0.0443 (7)
H7A0.12640.53940.40590.053*
C80.3218 (5)0.6278 (2)0.3067 (2)0.0505 (7)
H8A0.45550.62370.26220.061*
C90.1864 (5)0.7388 (2)0.3105 (2)0.0466 (7)
C100.1571 (6)0.9344 (2)0.2397 (2)0.0518 (7)
H10A0.18450.98680.30670.062*
H10B0.02490.91370.22350.062*
C110.2783 (6)1.0026 (2)0.1537 (2)0.0525 (7)
H11A0.25860.94680.08840.063*
H11B0.45941.02420.17200.063*
C120.1614 (5)1.1224 (2)0.1367 (2)0.0506 (7)
H12A0.02101.10080.12220.061*
H12B0.18771.17920.20150.061*
C130.2692 (6)1.1911 (3)0.0477 (2)0.0584 (8)
H13A0.24561.13390.01680.070*
H13B0.45121.21400.06290.070*
C140.1498 (7)1.3098 (3)0.0292 (3)0.0744 (10)
H14A0.03381.28840.01980.089*
H14B0.18601.37020.09150.089*
C150.2443 (8)1.3718 (3)0.0660 (3)0.0952 (13)
H15A0.16291.44640.07320.143*
H15B0.20441.31360.12840.143*
H15C0.42561.39470.05690.143*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0696 (14)0.0486 (12)0.0879 (15)0.0312 (10)0.0301 (12)0.0239 (10)
C10.0538 (17)0.0444 (15)0.0573 (17)0.0095 (13)0.0182 (14)0.0156 (13)
O20.0697 (13)0.0446 (11)0.0651 (12)0.0252 (10)0.0277 (10)0.0239 (9)
C20.0500 (17)0.0478 (16)0.0664 (19)0.0191 (14)0.0213 (15)0.0108 (14)
C30.0475 (16)0.0373 (14)0.0569 (17)0.0139 (12)0.0091 (13)0.0056 (12)
O30.0834 (16)0.0585 (13)0.0778 (14)0.0343 (11)0.0419 (12)0.0294 (11)
O40.0708 (13)0.0429 (11)0.0678 (13)0.0232 (10)0.0280 (11)0.0254 (10)
C40.0489 (16)0.0362 (14)0.0478 (15)0.0100 (12)0.0100 (13)0.0085 (12)
C50.0484 (16)0.0406 (15)0.0470 (15)0.0153 (12)0.0148 (13)0.0077 (12)
C60.0485 (16)0.0359 (14)0.0441 (14)0.0104 (12)0.0083 (12)0.0084 (11)
C70.0486 (17)0.0403 (15)0.0477 (16)0.0126 (13)0.0137 (13)0.0083 (12)
C80.0581 (18)0.0464 (16)0.0533 (17)0.0174 (14)0.0213 (14)0.0150 (13)
C90.0539 (17)0.0393 (15)0.0509 (16)0.0126 (13)0.0110 (14)0.0134 (12)
C100.0632 (19)0.0366 (14)0.0618 (18)0.0199 (13)0.0177 (15)0.0136 (13)
C110.0647 (19)0.0437 (15)0.0538 (16)0.0150 (14)0.0165 (14)0.0133 (13)
C120.0589 (18)0.0412 (15)0.0556 (17)0.0119 (13)0.0149 (14)0.0124 (13)
C130.072 (2)0.0495 (17)0.0578 (18)0.0131 (15)0.0152 (16)0.0156 (14)
C140.098 (3)0.0557 (19)0.077 (2)0.0170 (18)0.018 (2)0.0281 (17)
C150.134 (4)0.072 (2)0.083 (3)0.002 (2)0.007 (2)0.037 (2)
Geometric parameters (Å, º) top
O1—C31.357 (3)C8—H8A0.9300
O1—H1A0.8500C10—C111.499 (3)
C1—C21.377 (4)C10—H10A0.9700
C1—C61.392 (3)C10—H10B0.9700
C1—H1B0.9300C11—C121.516 (3)
O2—C41.371 (3)C11—H11A0.9700
O2—H2A0.8200C11—H11B0.9700
C2—C31.382 (3)C12—C131.507 (3)
C2—H2B0.9300C12—H12A0.9700
C3—C41.389 (3)C12—H12B0.9700
O3—C91.207 (3)C13—C141.516 (4)
O4—C91.326 (3)C13—H13A0.9700
O4—C101.449 (3)C13—H13B0.9700
C4—C51.375 (3)C14—C151.514 (4)
C5—C61.392 (3)C14—H14A0.9700
C5—H5A0.9300C14—H14B0.9700
C6—C71.459 (3)C15—H15A0.9600
C7—C81.317 (3)C15—H15B0.9600
C7—H7A0.9300C15—H15C0.9600
C8—C91.455 (3)
C3—O1—H1A118.8O4—C10—H10B110.4
C2—C1—C6120.5 (2)C11—C10—H10B110.4
C2—C1—H1B119.8H10A—C10—H10B108.6
C6—C1—H1B119.8C10—C11—C12112.0 (2)
C4—O2—H2A109.5C10—C11—H11A109.2
C1—C2—C3120.9 (2)C12—C11—H11A109.2
C1—C2—H2B119.6C10—C11—H11B109.2
C3—C2—H2B119.6C12—C11—H11B109.2
O1—C3—C2118.3 (2)H11A—C11—H11B107.9
O1—C3—C4122.3 (2)C13—C12—C11113.9 (2)
C2—C3—C4119.3 (2)C13—C12—H12A108.8
C9—O4—C10117.5 (2)C11—C12—H12A108.8
O2—C4—C5123.6 (2)C13—C12—H12B108.8
O2—C4—C3116.7 (2)C11—C12—H12B108.8
C5—C4—C3119.7 (2)H12A—C12—H12B107.7
C4—C5—C6121.6 (2)C12—C13—C14114.1 (3)
C4—C5—H5A119.2C12—C13—H13A108.7
C6—C5—H5A119.2C14—C13—H13A108.7
C5—C6—C1118.1 (2)C12—C13—H13B108.7
C5—C6—C7119.2 (2)C14—C13—H13B108.7
C1—C6—C7122.7 (2)H13A—C13—H13B107.6
C8—C7—C6127.7 (2)C15—C14—C13113.5 (3)
C8—C7—H7A116.1C15—C14—H14A108.9
C6—C7—H7A116.1C13—C14—H14A108.9
C7—C8—C9122.9 (2)C15—C14—H14B108.9
C7—C8—H8A118.5C13—C14—H14B108.9
C9—C8—H8A118.5H14A—C14—H14B107.7
O3—C9—O4122.9 (2)C14—C15—H15A109.5
O3—C9—C8125.4 (2)C14—C15—H15B109.5
O4—C9—C8111.7 (2)H15A—C15—H15B109.5
O4—C10—C11106.6 (2)C14—C15—H15C109.5
O4—C10—H10A110.4H15A—C15—H15C109.5
C11—C10—H10A110.4H15B—C15—H15C109.5
C6—C1—C2—C30.1 (4)C5—C6—C7—C8177.1 (3)
C1—C2—C3—O1179.5 (3)C1—C6—C7—C82.1 (5)
C1—C2—C3—C40.7 (4)C6—C7—C8—C9178.6 (3)
O1—C3—C4—O20.1 (4)C10—O4—C9—O30.3 (4)
C2—C3—C4—O2178.9 (2)C10—O4—C9—C8179.3 (2)
O1—C3—C4—C5179.9 (3)C7—C8—C9—O30.9 (5)
C2—C3—C4—C51.1 (4)C7—C8—C9—O4178.8 (3)
O2—C4—C5—C6179.0 (2)C9—O4—C10—C11175.1 (2)
C3—C4—C5—C60.9 (4)O4—C10—C11—C12177.5 (2)
C4—C5—C6—C10.4 (4)C10—C11—C12—C13177.4 (2)
C4—C5—C6—C7178.9 (2)C11—C12—C13—C14179.0 (3)
C2—C1—C6—C50.0 (4)C12—C13—C14—C15175.2 (3)
C2—C1—C6—C7179.3 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1A···O20.852.412.733 (2)103
O1—H1A···O2i0.852.072.857 (2)154
O2—H2A···O3ii0.821.972.786 (3)173
C5—H5A···O3ii0.932.543.243 (3)133
C7—H7A···O30.932.562.874 (3)100
Symmetry codes: (i) x+1, y, z+1; (ii) x, y+1, z+1.

Experimental details

Crystal data
Chemical formulaC15H20O4
Mr264.31
Crystal system, space groupTriclinic, P1
Temperature (K)293
a, b, c (Å)5.2920 (11), 10.689 (2), 12.732 (3)
α, β, γ (°)95.45 (3), 92.76 (3), 96.84 (3)
V3)710.6 (2)
Z2
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.20 × 0.10 × 0.10
Data collection
DiffractometerEnraf–Nonius CAD-4
diffractometer
Absorption correctionψ scan
(North et al., 1968)
Tmin, Tmax0.983, 0.991
No. of measured, independent and
observed [I > 2σ(I)] reflections
2912, 2608, 1515
Rint0.022
(sin θ/λ)max1)0.603
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.061, 0.178, 1.00
No. of reflections2608
No. of parameters172
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.19, 0.28

Computer programs: CAD-4 EXPRESS (Enraf–Nonius, 1994), XCAD4 (Harms & Wocadlo, 1995), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1A···O2i0.852.072.857 (2)154
O2—H2A···O3ii0.821.972.786 (3)173
C5—H5A···O3ii0.932.543.243 (3)133
Symmetry codes: (i) x+1, y, z+1; (ii) x, y+1, z+1.
 

Acknowledgements

This work was sponsored by the Qing Lan Project of Jiangsu Province, the Natural Science Foundation of Jiangsu Province (BK2009213), the College Natural Science Research Project of Jiangsu Province (08KJB530002), the Science and Technology Support Program of Jiangsu Province (BE2010419), the Start Project for Introducing Talent of Jiangsu University of Science and Technology (35211002), the Pre-research for NSFC Project of Jiangsu University of Science and Technology (33201002), and the earmarked fund for Modern Agro-industry Technology Research System (CARS-22).

References

First citationAllen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1–19.  CrossRef Web of Science Google Scholar
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