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

Wang, J.; Gu, S.-S.; Li, J.; Wu, F.-A.

doi:10.1107/S1600536811051671

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 68| Part 1| January 2012| Page o78

doi:10.1107/S1600536811051671

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

Jun Wang,^a Shuang-Shuang Gu,^a Jing Li ^a and Fu-An Wu ^a,^b ^*

^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 ); 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

Crystal data

C₁₅H₂₀O₄
M_r = 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 ) T_min = 0.983, T_max = 0.991
2912 measured reflections
2608 independent reflections
1515 reflections with I > 2σ(I)
R_int = 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
Δρ_max = 0.19 e Å⁻³
Δρ_min = −0.28 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	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 ); cell refinement: CAD-4 EXPRESS; 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 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811051671/aa2034sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811051671/aa2034Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811051671/aa2034Isup3.cml

checkCIF report

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%).

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

	Fig. 1. The molecular structure of the title molecule, with the atom numbering scheme. Thermal displacement ellipsoids are drawn at 30% probability level.
	Fig. 2. A partial packing diagram. Hydrogen bonds are shown as dashed lines.

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

Crystal data top

C₁₅H₂₀O₄	Z = 2
M_r = 264.31	F(000) = 284
Triclinic, P1	D_x = 1.235 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 5.2920 (11) Å	Cell parameters from 25 reflections
b = 10.689 (2) Å	θ = 9–13°
c = 12.732 (3) Å	µ = 0.09 mm⁻¹
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 tube	R_int = 0.022
Graphite monochromator	θ_max = 25.4°, θ_min = 1.6°
ω/2θ scans	h = 0→6
Absorption correction: ψ scan (North et al., 1968)	k = −12→12
T_min = 0.983, T_max = 0.991	l = −15→15
2912 measured reflections	3 standard reflections every 200 reflections
2608 independent reflections	intensity decay: 1%

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.061	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.178	H-atom parameters constrained
S = 1.00	w = 1/[σ²(F_o²) + (0.085P)² + 0.096P] where P = (F_o² + 2F_c²)/3
2608 reflections	(Δ/σ)_max < 0.001
172 parameters	Δρ_max = 0.19 e Å⁻³
0 restraints	Δρ_min = −0.28 e Å⁻³

Crystal data top

C₁₅H₂₀O₄	γ = 96.84 (3)°
M_r = 264.31	V = 710.6 (2) Å³
Triclinic, P1	Z = 2
a = 5.2920 (11) Å	Mo Kα radiation
b = 10.689 (2) Å	µ = 0.09 mm⁻¹
c = 12.732 (3) Å	T = 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)	R_int = 0.022
T_min = 0.983, T_max = 0.991	3 standard reflections every 200 reflections
2912 measured reflections	intensity decay: 1%
2608 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.061	0 restraints
wR(F²) = 0.178	H-atom parameters constrained
S = 1.00	Δρ_max = 0.19 e Å⁻³
2608 reflections	Δρ_min = −0.28 e Å⁻³
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

	x	y	z	U_iso*/U_eq
O1	0.7392 (4)	0.09426 (17)	0.38828 (16)	0.0649 (6)
H1A	0.6881	0.0408	0.4304	0.078*
C1	0.5906 (5)	0.3938 (2)	0.3065 (2)	0.0504 (7)
H1B	0.6496	0.4508	0.2597	0.060*
O2	0.3463 (4)	0.13532 (16)	0.51361 (14)	0.0564 (6)
H2A	0.2394	0.1617	0.5516	0.085*
C2	0.7038 (5)	0.2853 (2)	0.3144 (2)	0.0528 (8)
H2B	0.8390	0.2700	0.2730	0.063*
C3	0.6192 (5)	0.1991 (2)	0.3832 (2)	0.0463 (7)
O3	0.0120 (4)	0.75695 (18)	0.36537 (16)	0.0685 (7)
O4	0.2768 (4)	0.81988 (16)	0.24479 (15)	0.0571 (6)
C4	0.4190 (5)	0.2232 (2)	0.4456 (2)	0.0434 (7)
C5	0.3053 (5)	0.3312 (2)	0.43703 (19)	0.0440 (7)
H5A	0.1696	0.3462	0.4783	0.053*
C6	0.3883 (5)	0.4188 (2)	0.36794 (19)	0.0420 (6)
C7	0.2635 (5)	0.5329 (2)	0.36356 (19)	0.0443 (7)
H7A	0.1264	0.5394	0.4059	0.053*
C8	0.3218 (5)	0.6278 (2)	0.3067 (2)	0.0505 (7)
H8A	0.4555	0.6237	0.2622	0.061*
C9	0.1864 (5)	0.7388 (2)	0.3105 (2)	0.0466 (7)
C10	0.1571 (6)	0.9344 (2)	0.2397 (2)	0.0518 (7)
H10A	0.1845	0.9868	0.3067	0.062*
H10B	−0.0249	0.9137	0.2235	0.062*
C11	0.2783 (6)	1.0026 (2)	0.1537 (2)	0.0525 (7)
H11A	0.2586	0.9468	0.0884	0.063*
H11B	0.4594	1.0242	0.1720	0.063*
C12	0.1614 (5)	1.1224 (2)	0.1367 (2)	0.0506 (7)
H12A	−0.0210	1.1008	0.1222	0.061*
H12B	0.1877	1.1792	0.2015	0.061*
C13	0.2692 (6)	1.1911 (3)	0.0477 (2)	0.0584 (8)
H13A	0.2456	1.1339	−0.0168	0.070*
H13B	0.4512	1.2140	0.0629	0.070*
C14	0.1498 (7)	1.3098 (3)	0.0292 (3)	0.0744 (10)
H14A	−0.0338	1.2884	0.0198	0.089*
H14B	0.1860	1.3702	0.0915	0.089*
C15	0.2443 (8)	1.3718 (3)	−0.0660 (3)	0.0952 (13)
H15A	0.1629	1.4464	−0.0732	0.143*
H15B	0.2044	1.3136	−0.1284	0.143*
H15C	0.4256	1.3947	−0.0569	0.143*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0696 (14)	0.0486 (12)	0.0879 (15)	0.0312 (10)	0.0301 (12)	0.0239 (10)
C1	0.0538 (17)	0.0444 (15)	0.0573 (17)	0.0095 (13)	0.0182 (14)	0.0156 (13)
O2	0.0697 (13)	0.0446 (11)	0.0651 (12)	0.0252 (10)	0.0277 (10)	0.0239 (9)
C2	0.0500 (17)	0.0478 (16)	0.0664 (19)	0.0191 (14)	0.0213 (15)	0.0108 (14)
C3	0.0475 (16)	0.0373 (14)	0.0569 (17)	0.0139 (12)	0.0091 (13)	0.0056 (12)
O3	0.0834 (16)	0.0585 (13)	0.0778 (14)	0.0343 (11)	0.0419 (12)	0.0294 (11)
O4	0.0708 (13)	0.0429 (11)	0.0678 (13)	0.0232 (10)	0.0280 (11)	0.0254 (10)
C4	0.0489 (16)	0.0362 (14)	0.0478 (15)	0.0100 (12)	0.0100 (13)	0.0085 (12)
C5	0.0484 (16)	0.0406 (15)	0.0470 (15)	0.0153 (12)	0.0148 (13)	0.0077 (12)
C6	0.0485 (16)	0.0359 (14)	0.0441 (14)	0.0104 (12)	0.0083 (12)	0.0084 (11)
C7	0.0486 (17)	0.0403 (15)	0.0477 (16)	0.0126 (13)	0.0137 (13)	0.0083 (12)
C8	0.0581 (18)	0.0464 (16)	0.0533 (17)	0.0174 (14)	0.0213 (14)	0.0150 (13)
C9	0.0539 (17)	0.0393 (15)	0.0509 (16)	0.0126 (13)	0.0110 (14)	0.0134 (12)
C10	0.0632 (19)	0.0366 (14)	0.0618 (18)	0.0199 (13)	0.0177 (15)	0.0136 (13)
C11	0.0647 (19)	0.0437 (15)	0.0538 (16)	0.0150 (14)	0.0165 (14)	0.0133 (13)
C12	0.0589 (18)	0.0412 (15)	0.0556 (17)	0.0119 (13)	0.0149 (14)	0.0124 (13)
C13	0.072 (2)	0.0495 (17)	0.0578 (18)	0.0131 (15)	0.0152 (16)	0.0156 (14)
C14	0.098 (3)	0.0557 (19)	0.077 (2)	0.0170 (18)	0.018 (2)	0.0281 (17)
C15	0.134 (4)	0.072 (2)	0.083 (3)	0.002 (2)	0.007 (2)	0.037 (2)

Geometric parameters (Å, º) top

O1—C3	1.357 (3)	C8—H8A	0.9300
O1—H1A	0.8500	C10—C11	1.499 (3)
C1—C2	1.377 (4)	C10—H10A	0.9700
C1—C6	1.392 (3)	C10—H10B	0.9700
C1—H1B	0.9300	C11—C12	1.516 (3)
O2—C4	1.371 (3)	C11—H11A	0.9700
O2—H2A	0.8200	C11—H11B	0.9700
C2—C3	1.382 (3)	C12—C13	1.507 (3)
C2—H2B	0.9300	C12—H12A	0.9700
C3—C4	1.389 (3)	C12—H12B	0.9700
O3—C9	1.207 (3)	C13—C14	1.516 (4)
O4—C9	1.326 (3)	C13—H13A	0.9700
O4—C10	1.449 (3)	C13—H13B	0.9700
C4—C5	1.375 (3)	C14—C15	1.514 (4)
C5—C6	1.392 (3)	C14—H14A	0.9700
C5—H5A	0.9300	C14—H14B	0.9700
C6—C7	1.459 (3)	C15—H15A	0.9600
C7—C8	1.317 (3)	C15—H15B	0.9600
C7—H7A	0.9300	C15—H15C	0.9600
C8—C9	1.455 (3)

C3—O1—H1A	118.8	O4—C10—H10B	110.4
C2—C1—C6	120.5 (2)	C11—C10—H10B	110.4
C2—C1—H1B	119.8	H10A—C10—H10B	108.6
C6—C1—H1B	119.8	C10—C11—C12	112.0 (2)
C4—O2—H2A	109.5	C10—C11—H11A	109.2
C1—C2—C3	120.9 (2)	C12—C11—H11A	109.2
C1—C2—H2B	119.6	C10—C11—H11B	109.2
C3—C2—H2B	119.6	C12—C11—H11B	109.2
O1—C3—C2	118.3 (2)	H11A—C11—H11B	107.9
O1—C3—C4	122.3 (2)	C13—C12—C11	113.9 (2)
C2—C3—C4	119.3 (2)	C13—C12—H12A	108.8
C9—O4—C10	117.5 (2)	C11—C12—H12A	108.8
O2—C4—C5	123.6 (2)	C13—C12—H12B	108.8
O2—C4—C3	116.7 (2)	C11—C12—H12B	108.8
C5—C4—C3	119.7 (2)	H12A—C12—H12B	107.7
C4—C5—C6	121.6 (2)	C12—C13—C14	114.1 (3)
C4—C5—H5A	119.2	C12—C13—H13A	108.7
C6—C5—H5A	119.2	C14—C13—H13A	108.7
C5—C6—C1	118.1 (2)	C12—C13—H13B	108.7
C5—C6—C7	119.2 (2)	C14—C13—H13B	108.7
C1—C6—C7	122.7 (2)	H13A—C13—H13B	107.6
C8—C7—C6	127.7 (2)	C15—C14—C13	113.5 (3)
C8—C7—H7A	116.1	C15—C14—H14A	108.9
C6—C7—H7A	116.1	C13—C14—H14A	108.9
C7—C8—C9	122.9 (2)	C15—C14—H14B	108.9
C7—C8—H8A	118.5	C13—C14—H14B	108.9
C9—C8—H8A	118.5	H14A—C14—H14B	107.7
O3—C9—O4	122.9 (2)	C14—C15—H15A	109.5
O3—C9—C8	125.4 (2)	C14—C15—H15B	109.5
O4—C9—C8	111.7 (2)	H15A—C15—H15B	109.5
O4—C10—C11	106.6 (2)	C14—C15—H15C	109.5
O4—C10—H10A	110.4	H15A—C15—H15C	109.5
C11—C10—H10A	110.4	H15B—C15—H15C	109.5

C6—C1—C2—C3	0.1 (4)	C5—C6—C7—C8	177.1 (3)
C1—C2—C3—O1	−179.5 (3)	C1—C6—C7—C8	−2.1 (5)
C1—C2—C3—C4	−0.7 (4)	C6—C7—C8—C9	−178.6 (3)
O1—C3—C4—O2	−0.1 (4)	C10—O4—C9—O3	−0.3 (4)
C2—C3—C4—O2	−178.9 (2)	C10—O4—C9—C8	179.3 (2)
O1—C3—C4—C5	179.9 (3)	C7—C8—C9—O3	0.9 (5)
C2—C3—C4—C5	1.1 (4)	C7—C8—C9—O4	−178.8 (3)
O2—C4—C5—C6	179.0 (2)	C9—O4—C10—C11	−175.1 (2)
C3—C4—C5—C6	−0.9 (4)	O4—C10—C11—C12	177.5 (2)
C4—C5—C6—C1	0.4 (4)	C10—C11—C12—C13	−177.4 (2)
C4—C5—C6—C7	−178.9 (2)	C11—C12—C13—C14	179.0 (3)
C2—C1—C6—C5	0.0 (4)	C12—C13—C14—C15	−175.2 (3)
C2—C1—C6—C7	179.3 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1A···O2	0.85	2.41	2.733 (2)	103
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
C7—H7A···O3	0.93	2.56	2.874 (3)	100

Symmetry codes: (i) −x+1, −y, −z+1; (ii) −x, −y+1, −z+1.

Experimental details

Crystal data
Chemical formula	C₁₅H₂₀O₄
M_r	264.31
Crystal system, space group	Triclinic, 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)
V (Å³)	710.6 (2)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.20 × 0.10 × 0.10

Data collection
Diffractometer	Enraf–Nonius CAD-4 diffractometer
Absorption correction	ψ scan (North et al., 1968)
T_min, T_max	0.983, 0.991
No. of measured, independent and observed [I > 2σ(I)] reflections	2912, 2608, 1515
R_int	0.022
(sin θ/λ)_max (Å⁻¹)	0.603

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.061, 0.178, 1.00
No. of reflections	2608
No. of parameters	172
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	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···A	D—H	H···A	D···A	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.

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).

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