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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 64| Part 8| August 2008| Page o1458
doi:10.1107/S160053680802103X

2-(4-Eth­oxy­benzyl­­idene)butanoic acid

Niaz Muhammad,a M. Nawaz Tahir,b* Zia-ur-Rehmana and Saqib Alia

aDepartment of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan, and bDepartment of Physics, University of Sargodha, Sagrodha, Pakistan
*Correspondence e-mail: dmntahir_uos@yahoo.com

(Received 2 July 2008; accepted 7 July 2008; online 12 July 2008)

In the crystal structure of the title compound, C13H16O3, dimers are formed due to inter­molecular O—H⋯O hydrogen bonding. There exists an intra­molecular C—H⋯O hydrogen bond which forms a five-membered ring. There is also present a C—H⋯π inter­action between a methyl CH group of an ethyl group and the centroid of the aromatic ring.

Related literature

For related literature, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]); Burt (2004[Burt, S. (2004). Int. J. Food Microbiol. 94, 223-253.]); Muhammad et al. (2007[Muhammad, N., Zia-ur-Rehman, Ali, S. & Meetsma, A. (2007). Acta Cryst. E63, o2174-o2175.], 2008a[Muhammad, N., Ali, S., Tahir, M. N. & Zia-ur-Rehman (2008a). Acta Cryst. E64, o1373.],b[Muhammad, N., Tahir, M. N., Ali, S. & Zia-ur-Rehman (2008b). Acta Cryst. E64, m946-m947.],c[Muhammad, N., Tahir, M. N., Ali, S. & Zia-ur-Rehman (2008c). Acta Cryst. E64, m978.]); Niaz et al. (2008[Niaz, M., Tahir, M. N., Zia-ur-Rehman, Ali, S. & Khan, I. U. (2008). Acta Cryst. E64, o733.]).

[Scheme 1]

Experimental

Crystal data

  • C13H16O3

  • Mr = 220.26

  • Monoclinic, P 21 /c

  • a = 10.3192 (7) Å

  • b = 22.0761 (15) Å

  • c = 5.2362 (3) Å

  • β = 100.751 (4)°

  • V = 1171.91 (13) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 296 (2) K

  • 0.26 × 0.20 × 0.16 mm
Data collection

  • Bruker Kappa APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2005[Bruker (2005). SADABS. Bruker AXS Inc. Madison, Wisconsin, USA.]) Tmin = 0.975, Tmax = 0.985

  • 13990 measured reflections

  • 3009 independent reflections

  • 1599 reflections with I > 2σ(I)

  • Rint = 0.049
Refinement

  • R[F2 > 2σ(F2)] = 0.050

  • wR(F2) = 0.122

  • S = 1.00

  • 3009 reflections

  • 150 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.14 e Å−3

  • Δρmin = −0.21 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O1—H1⋯O2i 1.01 (2) 1.61 (2) 2.6184 (15) 176.8 (15)
C7—H7⋯O1 0.93 2.30 2.7218 (19) 107
C12—H12B⋯CgAii 0.96 2.82 3.6534 (19) 145
Symmetry codes: (i) -x+1, -y, -z-1; (ii) x, y, z+1. CgA is the centroid of the C1–C6 ring.

Data collection: APEX2 (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc. Madison, Wisconsin, USA.]); cell refinement: APEX2; data reduction: SAINT (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc. Madison, Wisconsin, USA.]); 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: ORTEP-3 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]) and PLATON.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S160053680802103X/at2588sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053680802103X/at2588Isup2.hkl

checkCIF report


Comment top

Cinnamic acid derivatives play an important role in the production of lignins for higher plants. They are well documented for their antibacterial, antifungal and antiparasitic activities (Burt, 2004). We have recently reported the various derivatives of cinamic acids (Niaz et al., 2008, Muhammad et al., 2008a) and tin complexes (Muhammad et al., 2008b, 2008c). In continuation of our project, we herein report the structure of the title compound (I).

The crystal structure of 3-(4-bromophenyl)-2-ethylacrylic acid (II) (Muhammad et al., 2007) differs from (I) due to the attachement of ethoxy group at para position instead of Br-atom. Similarly, (E) -2-(2-fluorobenzylidene) butanoic acid (III) (Niaz et al., 2008) differs as the attachment of F-atom is on meta position. Thus, (I) is very different from the reported compounds (II) and (III).

In the crystal structure of the title compound (I), the C—C bonds are in the range 1.464 (2) to 1.511 (2) Å, and C═C have a value of 1.337 (2) Å. The value of C—O bond in the carboxylate group is 1.287 (2) Å, whereas C═O is of 1.248 (2) Å. The attached ethoxy group have 1.3595 (19) and 1.431 (2) Å as the C—O bond distances. In the asymmetric unit, there is an interamolecular H-bond of C—H···O type (Table 1, Fig 1) which completes a five membered ring (O1/C9/C8/C7/H7). Centrosymmetric dimers, R22(8) (Bernstein et al. 1995) are formed due to the intermolecular hydrogen bonding, O1—H1···O2i [symmetry code: (i) = -x + 1, -y, -z - 1]. These dimers have a π-interaction C12—H12B···CgAii [symmetry code: (ii) = x, y, z + 1] where CgA is the centroid of the aromatic ring A(C1—C6). The dihedral angle between (O1/C9/O2) and (C8/C10/C11) is 75.55 (15)°, whereas it is 30.19 (17)° between (C7/C8/C9) and (O3/C12/C13). The ethoxy group makes a dihedral angle of 2.77 (11)° with the aromatic ring. The formation of centrosymmetric dimers and packing of (I) is shown in Fig 2.

Related literature top

For related literature, see: Bernstein et al. (1995); Burt (2004); Muhammad et al. (2007, 2008a,b,c); Niaz et al. (2008). CgA is the

centroid of the C1–C6 ring.

Experimental top

Compound (I) was prepared according to the reported procedure (Muhammad et al., 2007). A mixture of 4-ethoxybenzaldehyde(1.39 ml, 10 mmol), ethylmalonic acid (2.64 g, 20 mmol) and piperidine (1.98 ml, 20 mmol) in a pyridine (12.5 ml) solution was heated on a steam-bath for 24 h. The reaction mixture was cooled and added to a mixture of 25 ml of concentrated HCl and 50 g of ice. The precipitate formed in the acidified mixture was filtered off and washed with ice-cold water. The product was recrystallized from ethanol [yield: 66%].

Refinement top

The H-atom of carboxylate group is taken from fourier difference map and coordinates were refined. The other H atoms were positioned geometrically, with C—H = 0.93, 0.97, and 0.96 Å for aromatic, methylene and methyl H, respectively, and constrained to ride on their parent atoms, with Uiso(H) = xUeq(C, O), where x = 1.5 for methyl H, and x = 1.2 for all other H atoms.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: APEX2 (Bruker, 2007); data reduction: SAINT (Bruker, 2007); 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) and PLATON (Spek, 2003); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2003).

Figures top
[Figure 1] Fig. 1. ORTEP drawing of the title compound, with the atom numbering scheme. The thermal ellipsoids are drawn at the 50% probability level. H-atoms are shown by small circles of arbitrary radii. The intramolecular H-bonds are shown by doted lines.
[Figure 2] Fig. 2. The packing figure (PLATON: Spek, 2003) which shows the dimeric nature of the compound and the interlinkages of the dimers.
2-(4-Ethoxybenzylidene)butanoic acid top
Crystal data top
C13H16O3F(000) = 472
Mr = 220.26Dx = 1.248 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3009 reflections
a = 10.3192 (7) Åθ = 2.0–28.7°
b = 22.0761 (15) ŵ = 0.09 mm−1
c = 5.2362 (3) ÅT = 296 K
β = 100.751 (4)°Prismatic, colourless
V = 1171.91 (13) Å30.26 × 0.20 × 0.16 mm
Z = 4
Data collection top
Bruker KappaAPEXII CCD
diffractometer		3009 independent reflections
Radiation source: fine-focus sealed tube1599 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.049
Detector resolution: 7.4 pixels mm-1θmax = 28.7°, θmin = 2.0°
ω scansh = −13→13
Absorption correction: multi-scan
(SADABS; Bruker, 2005)		k = −29→29
Tmin = 0.975, Tmax = 0.985l = −7→6
13990 measured reflections
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)] = 0.050Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.122H atoms treated by a mixture of independent and constrained refinement
S = 1.01 w = 1/[σ2(Fo2) + (0.0465P)2 + 0.113P]
where P = (Fo2 + 2Fc2)/3
3009 reflections(Δ/σ)max < 0.001
150 parametersΔρmax = 0.15 e Å−3
0 restraintsΔρmin = −0.21 e Å−3
Crystal data top
C13H16O3V = 1171.91 (13) Å3
Mr = 220.26Z = 4
Monoclinic, P21/cMo Kα radiation
a = 10.3192 (7) ŵ = 0.09 mm−1
b = 22.0761 (15) ÅT = 296 K
c = 5.2362 (3) Å0.26 × 0.20 × 0.16 mm
β = 100.751 (4)°
Data collection top
Bruker KappaAPEXII CCD
diffractometer		3009 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)		1599 reflections with I > 2σ(I)
Tmin = 0.975, Tmax = 0.985Rint = 0.049
13990 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0500 restraints
wR(F2) = 0.122H atoms treated by a mixture of independent and constrained refinement
S = 1.01Δρmax = 0.15 e Å−3
3009 reflectionsΔρmin = −0.21 e Å−3
150 parameters
Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

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
O10.62469 (12)−0.00644 (5)−0.2194 (2)0.0545 (4)
O20.47639 (13)0.06481 (5)−0.3546 (2)0.0577 (5)
O31.08170 (11)0.17222 (5)1.0247 (2)0.0506 (4)
C10.82240 (15)0.09272 (7)0.4115 (3)0.0388 (5)
C20.89602 (16)0.05704 (7)0.6035 (3)0.0437 (6)
C30.98214 (17)0.08106 (7)0.8122 (3)0.0447 (6)
C40.99847 (16)0.14314 (7)0.8316 (3)0.0396 (5)
C50.92792 (17)0.17994 (7)0.6416 (3)0.0457 (6)
C60.84164 (17)0.15537 (7)0.4371 (3)0.0461 (6)
C70.73819 (16)0.06338 (7)0.1901 (3)0.0420 (6)
C80.63076 (16)0.08379 (7)0.0301 (3)0.0385 (5)
C90.57279 (17)0.04572 (7)−0.1946 (3)0.0411 (5)
C100.55968 (18)0.14224 (7)0.0567 (3)0.0456 (6)
C110.5866 (2)0.19159 (8)−0.1265 (3)0.0613 (7)
C121.16254 (18)0.13667 (8)1.2209 (3)0.0523 (6)
C131.2471 (2)0.17960 (10)1.4013 (4)0.0696 (8)
H10.5832 (17)−0.0279 (8)−0.385 (4)0.0654*
H20.886960.015180.591000.0525*
H31.028790.055710.938770.0537*
H50.939080.221720.652630.0548*
H60.794660.180980.312050.0553*
H70.763480.024280.155100.0503*
H10A0.585220.156700.233930.0547*
H10B0.465580.134340.025990.0547*
H11A0.564670.17725−0.302400.0919*
H11B0.678250.20238−0.087280.0919*
H11C0.533850.22647−0.106320.0919*
H12A1.217220.109231.142390.0627*
H12B1.107910.112921.315260.0627*
H13A1.302780.201851.306920.1044*
H13B1.300680.157181.538860.1044*
H13C1.191910.207301.473590.1044*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0617 (9)0.0404 (7)0.0544 (7)0.0025 (6)−0.0076 (6)−0.0162 (5)
O20.0623 (9)0.0493 (8)0.0515 (7)0.0067 (6)−0.0149 (7)−0.0126 (6)
O30.0561 (8)0.0421 (7)0.0456 (7)−0.0019 (6)−0.0109 (6)−0.0018 (5)
C10.0377 (10)0.0378 (9)0.0402 (9)−0.0003 (7)0.0053 (8)−0.0036 (7)
C20.0484 (11)0.0316 (9)0.0501 (10)−0.0018 (8)0.0066 (9)−0.0015 (7)
C30.0477 (11)0.0397 (10)0.0434 (10)0.0012 (8)−0.0002 (8)0.0037 (7)
C40.0391 (10)0.0395 (9)0.0387 (9)−0.0009 (8)0.0034 (8)−0.0049 (7)
C50.0504 (11)0.0312 (9)0.0507 (10)−0.0010 (8)−0.0027 (9)−0.0027 (8)
C60.0481 (11)0.0380 (9)0.0470 (9)0.0008 (8)−0.0044 (8)0.0016 (7)
C70.0478 (11)0.0347 (9)0.0430 (9)−0.0017 (8)0.0075 (8)−0.0048 (7)
C80.0414 (10)0.0367 (9)0.0365 (9)−0.0037 (8)0.0053 (8)−0.0042 (7)
C90.0444 (10)0.0344 (9)0.0433 (9)−0.0038 (8)0.0048 (8)−0.0047 (7)
C100.0460 (11)0.0468 (10)0.0425 (9)0.0009 (8)0.0041 (8)−0.0099 (8)
C110.0821 (15)0.0456 (11)0.0513 (11)0.0044 (10)−0.0003 (10)−0.0010 (8)
C120.0490 (12)0.0516 (11)0.0507 (10)0.0063 (9)−0.0054 (9)0.0003 (8)
C130.0603 (14)0.0705 (14)0.0663 (13)0.0025 (11)−0.0183 (11)−0.0055 (11)
Geometric parameters (Å, º) top
O1—C91.287 (2)C12—C131.498 (3)
O2—C91.248 (2)C2—H20.9300
O3—C41.3595 (19)C3—H30.9300
O3—C121.431 (2)C5—H50.9300
O1—H11.01 (2)C6—H60.9300
C1—C21.387 (2)C7—H70.9300
C1—C61.400 (2)C10—H10A0.9700
C1—C71.464 (2)C10—H10B0.9700
C2—C31.379 (2)C11—H11A0.9600
C3—C41.382 (2)C11—H11B0.9600
C4—C51.382 (2)C11—H11C0.9600
C5—C61.370 (2)C12—H12A0.9700
C7—C81.337 (2)C12—H12B0.9700
C8—C91.479 (2)C13—H13A0.9600
C8—C101.504 (2)C13—H13B0.9600
C10—C111.511 (2)C13—H13C0.9600
C4—O3—C12118.54 (12)C1—C6—H6119.00
C9—O1—H1112.9 (10)C5—C6—H6119.00
C2—C1—C6116.29 (14)C1—C7—H7115.00
C6—C1—C7124.44 (14)C8—C7—H7115.00
C2—C1—C7119.13 (14)C8—C10—H10A109.00
C1—C2—C3122.74 (14)C8—C10—H10B109.00
C2—C3—C4119.41 (15)C11—C10—H10A109.00
O3—C4—C5115.64 (14)C11—C10—H10B109.00
C3—C4—C5119.30 (15)H10A—C10—H10B108.00
O3—C4—C3125.05 (14)C10—C11—H11A109.00
C4—C5—C6120.54 (14)C10—C11—H11B109.00
C1—C6—C5121.71 (15)C10—C11—H11C109.00
C1—C7—C8130.35 (15)H11A—C11—H11B109.00
C7—C8—C9118.18 (14)H11A—C11—H11C109.00
C9—C8—C10115.44 (14)H11B—C11—H11C109.00
C7—C8—C10126.37 (14)O3—C12—H12A110.00
O1—C9—O2121.94 (14)O3—C12—H12B110.00
O1—C9—C8118.35 (14)C13—C12—H12A110.00
O2—C9—C8119.72 (14)C13—C12—H12B110.00
C8—C10—C11114.16 (15)H12A—C12—H12B109.00
O3—C12—C13107.38 (15)C12—C13—H13A109.00
C1—C2—H2119.00C12—C13—H13B109.00
C3—C2—H2119.00C12—C13—H13C109.00
C2—C3—H3120.00H13A—C13—H13B110.00
C4—C3—H3120.00H13A—C13—H13C109.00
C4—C5—H5120.00H13B—C13—H13C109.00
C6—C5—H5120.00
C12—O3—C4—C32.0 (2)O3—C4—C5—C6179.67 (15)
C12—O3—C4—C5−176.99 (14)C3—C4—C5—C60.6 (3)
C4—O3—C12—C13177.96 (14)C4—C5—C6—C1−0.5 (3)
C6—C1—C2—C31.2 (2)C1—C7—C8—C9174.19 (16)
C7—C1—C2—C3177.04 (16)C1—C7—C8—C10−6.8 (3)
C2—C1—C6—C5−0.4 (2)C7—C8—C9—O13.1 (2)
C7—C1—C6—C5−176.02 (16)C7—C8—C9—O2−176.51 (16)
C2—C1—C7—C8156.09 (18)C10—C8—C9—O1−176.06 (14)
C6—C1—C7—C8−28.4 (3)C10—C8—C9—O24.4 (2)
C1—C2—C3—C4−1.1 (3)C7—C8—C10—C11103.29 (19)
C2—C3—C4—O3−178.82 (15)C9—C8—C10—C11−77.65 (19)
C2—C3—C4—C50.1 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O2i1.01 (2)1.61 (2)2.6184 (15)176.8 (15)
C7—H7···O10.932.302.7218 (19)107
C12—H12B···CgAii0.962.823.6534 (19)145
Symmetry codes: (i) −x+1, −y, −z−1; (ii) x, y, z+1.

Experimental details

Crystal data
Chemical formulaC13H16O3
Mr220.26
Crystal system, space groupMonoclinic, P21/c
Temperature (K)296
a, b, c (Å)10.3192 (7), 22.0761 (15), 5.2362 (3)
β (°) 100.751 (4)
V (Å3)1171.91 (13)
Z4
Radiation typeMo Kα
µ (mm−1)0.09
Crystal size (mm)0.26 × 0.20 × 0.16
Data collection
DiffractometerBruker KappaAPEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.975, 0.985
No. of measured, independent and
observed [I > 2σ(I)] reflections		13990, 3009, 1599
Rint0.049
(sin θ/λ)max (Å−1)0.676
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.050, 0.122, 1.01
No. of reflections3009
No. of parameters150
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)0.15, −0.21

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2003), WinGX (Farrugia, 1999) and PLATON (Spek, 2003).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O2i1.01 (2)1.61 (2)2.6184 (15)176.8 (15)
C7—H7···O10.932.302.7218 (19)107
C12—H12B···CgAii0.962.823.6534 (19)145
Symmetry codes: (i) −x+1, −y, −z−1; (ii) x, y, z+1.
 

Acknowledgements

The authors acknowledge the Higher Education Commission, Islamabad, Pakistan, for funding the purchase of the diffractometer at GCU, Lahore, and for financial support to NM for PhD studies under the Indigenous Scholarship Scheme.

References

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ISSN: 2056-9890
Volume 64| Part 8| August 2008| Page o1458
doi:10.1107/S160053680802103X
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