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Acta Cryst. (2009). E65, o70    [ doi:10.1107/S1600536808040130 ]

Ethyl 6-(4-ethoxyphenyl)-4-(furan-2-yl)-2-oxocyclohex-3-ene-1-carboxylate

A. Badshah, A. Hasan, C. R. Barbarín, A. Abbas and S. Ali

Abstract top

The title compound, C21H22O5, was prepared by NaOH-catalysed cyclocondensation of 3-(4-ethoxyphenyl)-1-(furan-2-yl)prop-2-en-1-one with ethyl acetoacetate. In the crystal, C-H...O and C-H...[pi] interactions link the molecules. In the title molecule, the furan and cyclohexene rings are almost parallel [6.77 (11)°] and the cyclohexene ring is approximately perpendicular to the benzene ring [84.79 (5)°].

Comment top

Cyclohexenones are prepared either from natural sources or entirely via synthetic routes. The motive for their preparation is a variety of medical effects. The molecules have anticonvulsant, antimalarial, anti-inflammatory and cardiovascular effects (Eddington et al., 2000). Cyclohexenones are also important intermediates for many biologically active compounds (Padmavathi et al., 2000, 2001). A series of novel compounds has been synthesized, known as cyclohexenoic long chain fatty alcohols, which are used in the treatment of neurological disorders (Luu et al., 2000). A number of their derivatives have fungicidal and antitumor activities (Li et al., 2001).

The title compound (Fig. 1) is a derivative of 1-(furan-2-yl)-3-(4-ethoxyphenyl)prop-2-en-1-one.

Two rings of the title molecule, i.e. furan-2-yl [O1\C1 ··· C4] and the cyclohexene [C5 ··· C10], are almost parallel containing 6.77 (11)°. Cyclohexene is approximately perpendicular to the benzene ring [C14 ··· C19], containing 84.79 (05)°. The title molecule has two asymmetric carbon atoms C8 and C9. The respective configurations are SR and RS within the racemic pair in the structure.

There are weak intermolecular interactions only in the structure that are indicated by geometry, X-H···O and C—H···π-electron ring contacts (Tab. 1). The molecular packing is shown in Fig. 2.

Related literature top

For background to cyclohexenones, see: Eddington et al. (2000); Li & Strobel (2001); Luu et al. (2000); Padmavathi et al. (2000, 2001).

Experimental top

The title compound was synthesized by refluxing ethyl acetoacetate (0.39 g, 0.40 ml, 3 mmol) with 1-(furan-2-yl)-3-(4-ethoxyphenyl)prop-2-en-1-one (3 mmol, 0.726 g) for 2 h in 10–15 ml of ethanol in presence of 0.5 ml 10% NaOH as shown in Fig. 3. The reaction mixture was then poured while having been stirred intensively into 200 ml of ice-cold water. The mixture was kept at room temperature until the reaction product separated as a solid, which was filtered off and recrystallized from ethanol. The grown crystals were prismatic, yellow and with approximate dimensions of 0.4×0.4×0.6 mm. Yield: 70%, m.p.: 388 K.

Refinement top

All the hydrogen atoms could have been discerned in the difference electron density map. Nevertheless, all the H-atoms were placed into idealized positions and refined as riding atoms at constrained distances: Caryl—H = 0.93, Cmethine—H = 0.98, Cmethylene—H = 0.97 and Cmethyl—H = 0.96 Å, while UisoH = 1.5UeqCmethyl or 1.2UeqCaryl/methylene/methine.

Computing details top

Data collection: XSCANS (Siemens, 1999); cell refinement: XSCANS (Siemens, 1999); data reduction: XSCANS (Siemens, 1999); program(s) used to solve structure: SHELXTL-Plus (Sheldrick, 2008); program(s) used to refine structure: SHELXTL-Plus (Sheldrick, 2008); molecular graphics: SHELXTL-Plus (Sheldrick, 2008) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXTL-Plus (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The title molecule showing the atom-labelling scheme. The displacement ellipsoids are drawn at the 40% probability level and the H atoms are shown as small spheres of arbitrary radii.
[Figure 2] Fig. 2. The packing diagram of the title compound, viewed along the the a-axis showing the weak hydrogen-bond and C—H···π electron interactions.
[Figure 3] Fig. 3. Preparation of the title compound.
(1SR,6RS)-Ethyl 6-(4-ethoxyphenyl)-4-(furan-2-yl)-2-oxocyclohex-3-ene-1-carboxylate top
Crystal data top
C21H22O5F(000) = 752
Mr = 354.39Dx = 1.313 Mg m−3
Monoclinic, P21/nMelting point: 388 K
Hall symbol: -P 2ynMo Kα radiation, λ = 0.71073 Å
a = 7.361 (3) ÅCell parameters from 86 reflections
b = 17.350 (4) Åθ = 4.6–12.9°
c = 14.473 (3) ŵ = 0.09 mm−1
β = 104.07 (2)°T = 298 K
V = 1792.8 (9) Å3Prism, yellow
Z = 40.60 × 0.40 × 0.40 mm
Data collection top
Bruker P4
diffractometer		Rint = 0.021
Radiation source: fine-focus sealed tubeθmax = 30.0°, θmin = 2.4°
graphiteh = −10→4
ω scansk = −24→1
8745 measured reflectionsl = −20→20
5218 independent reflections3 standard reflections every 97 reflections
3806 reflections with I > 2σ(I) intensity decay: 3.4%
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)] = 0.047Hydrogen site location: difference Fourier map
wR(F2) = 0.135H-atom parameters constrained
S = 1.06 w = 1/[σ2(Fo2) + (0.057P)2 + 0.3325P]
where P = (Fo2 + 2Fc2)/3
5218 reflections(Δ/σ)max < 0.001
237 parametersΔρmax = 0.27 e Å−3
0 restraintsΔρmin = −0.17 e Å−3
86 constraints
Crystal data top
C21H22O5V = 1792.8 (9) Å3
Mr = 354.39Z = 4
Monoclinic, P21/nMo Kα radiation
a = 7.361 (3) ŵ = 0.09 mm−1
b = 17.350 (4) ÅT = 298 K
c = 14.473 (3) Å0.60 × 0.40 × 0.40 mm
β = 104.07 (2)°
Data collection top
Bruker P4
diffractometer		Rint = 0.021
8745 measured reflectionsθmax = 30.0°
5218 independent reflections3 standard reflections every 97 reflections
3806 reflections with I > 2σ(I) intensity decay: 3.4%
Refinement top
R[F2 > 2σ(F2)] = 0.047H-atom parameters constrained
wR(F2) = 0.135Δρmax = 0.27 e Å−3
S = 1.06Δρmin = −0.17 e Å−3
5218 reflectionsAbsolute structure: ?
237 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
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
O1−0.07980 (14)0.45302 (6)0.31575 (9)0.0611 (3)
O20.43726 (17)0.45205 (7)0.60674 (8)0.0646 (3)
O30.67391 (17)0.29800 (7)0.65190 (8)0.0627 (3)
O40.86811 (14)0.37514 (6)0.59822 (8)0.0571 (3)
O51.03226 (14)0.08582 (5)0.40318 (7)0.0495 (2)
C1−0.2189 (2)0.45660 (10)0.23520 (15)0.0697 (5)
H1A−0.32270.48880.22670.084*
C2−0.1874 (2)0.40812 (10)0.16994 (13)0.0642 (4)
H2A−0.26280.40040.10900.077*
C3−0.0168 (2)0.37048 (9)0.21122 (11)0.0514 (3)
H3A0.04160.33280.18290.062*
C40.04471 (17)0.39962 (7)0.29930 (10)0.0439 (3)
C50.21001 (17)0.38693 (7)0.37425 (10)0.0411 (3)
C60.23954 (19)0.42500 (8)0.45737 (11)0.0488 (3)
H6A0.14590.45740.46790.059*
C70.4111 (2)0.41770 (8)0.53120 (10)0.0471 (3)
C80.56299 (18)0.36875 (7)0.50669 (9)0.0422 (3)
H8A0.62830.40040.46880.051*
C90.47735 (17)0.29939 (7)0.44584 (9)0.0394 (3)
H9A0.39860.27180.48060.047*
C100.34964 (17)0.33007 (8)0.35447 (9)0.0415 (3)
H10A0.42490.35480.31650.050*
H10B0.28350.28740.31790.050*
C110.7048 (2)0.34303 (8)0.59512 (9)0.0457 (3)
C121.0290 (2)0.34644 (11)0.66794 (13)0.0672 (5)
H12A0.99310.33320.72620.081*
H12B1.12480.38600.68270.081*
C131.1037 (3)0.27755 (12)0.62977 (14)0.0757 (5)
H13A1.22360.26450.67020.114*
H13B1.11700.28820.56670.114*
H13C1.01890.23520.62770.114*
C140.62510 (16)0.24380 (7)0.43058 (8)0.0373 (2)
C150.6367 (2)0.17049 (8)0.46933 (10)0.0454 (3)
H15A0.55010.15550.50310.054*
C160.7726 (2)0.11937 (8)0.45920 (10)0.0482 (3)
H16A0.77730.07050.48610.058*
C170.90234 (17)0.14023 (7)0.40922 (9)0.0381 (3)
C180.89386 (18)0.21308 (7)0.36978 (10)0.0420 (3)
H18A0.98030.22790.33580.050*
C190.75621 (18)0.26366 (7)0.38113 (10)0.0431 (3)
H19A0.75180.31260.35460.052*
C201.1525 (2)0.10138 (8)0.34250 (11)0.0516 (3)
H20A1.23280.14490.36650.062*
H20B1.07950.11370.27890.062*
C211.2679 (3)0.03130 (10)0.33988 (16)0.0721 (5)
H21A1.34380.03890.29530.108*
H21B1.1871−0.01220.32060.108*
H21C1.34710.02200.40210.108*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0433 (5)0.0450 (5)0.0870 (8)0.0109 (4)0.0004 (5)−0.0034 (5)
O20.0676 (7)0.0628 (7)0.0603 (6)0.0169 (5)0.0094 (5)−0.0202 (5)
O30.0758 (8)0.0597 (7)0.0523 (6)0.0065 (6)0.0152 (5)0.0072 (5)
O40.0461 (6)0.0526 (6)0.0649 (6)0.0054 (4)−0.0016 (5)0.0015 (5)
O50.0533 (6)0.0412 (5)0.0612 (6)0.0136 (4)0.0276 (5)0.0092 (4)
C10.0432 (8)0.0489 (8)0.1032 (14)0.0069 (6)−0.0088 (8)0.0089 (9)
C20.0507 (8)0.0561 (9)0.0740 (10)−0.0053 (7)−0.0081 (7)0.0176 (8)
C30.0451 (7)0.0488 (7)0.0575 (8)−0.0019 (6)0.0068 (6)0.0090 (6)
C40.0351 (6)0.0335 (6)0.0620 (8)0.0017 (5)0.0095 (5)0.0077 (5)
C50.0351 (6)0.0344 (6)0.0540 (7)0.0007 (5)0.0110 (5)0.0047 (5)
C60.0429 (7)0.0422 (7)0.0612 (8)0.0107 (6)0.0123 (6)−0.0033 (6)
C70.0482 (7)0.0392 (6)0.0532 (7)0.0068 (5)0.0109 (6)−0.0051 (6)
C80.0409 (6)0.0375 (6)0.0467 (6)0.0037 (5)0.0078 (5)−0.0007 (5)
C90.0384 (6)0.0371 (6)0.0435 (6)0.0038 (5)0.0119 (5)−0.0010 (5)
C100.0360 (6)0.0418 (6)0.0458 (6)0.0034 (5)0.0083 (5)−0.0012 (5)
C110.0514 (7)0.0393 (6)0.0442 (7)0.0092 (6)0.0076 (5)−0.0061 (5)
C120.0538 (9)0.0695 (10)0.0660 (10)0.0137 (8)−0.0094 (7)−0.0107 (8)
C130.0679 (11)0.0849 (13)0.0670 (10)0.0279 (10)0.0021 (8)−0.0060 (9)
C140.0368 (6)0.0366 (6)0.0381 (6)0.0038 (5)0.0081 (5)−0.0020 (5)
C150.0512 (7)0.0416 (7)0.0499 (7)0.0034 (5)0.0251 (6)0.0051 (5)
C160.0597 (8)0.0352 (6)0.0572 (8)0.0075 (6)0.0286 (6)0.0095 (6)
C170.0392 (6)0.0354 (6)0.0405 (6)0.0052 (5)0.0111 (5)0.0006 (5)
C180.0389 (6)0.0400 (6)0.0502 (7)0.0018 (5)0.0169 (5)0.0074 (5)
C190.0424 (7)0.0354 (6)0.0529 (7)0.0041 (5)0.0144 (5)0.0083 (5)
C200.0475 (7)0.0490 (7)0.0645 (9)0.0072 (6)0.0260 (7)0.0040 (6)
C210.0684 (11)0.0543 (9)0.1091 (15)0.0148 (8)0.0516 (11)0.0028 (9)
Geometric parameters (Å, °) top
O1—C11.353 (2)C9—H9A0.9800
O1—C41.3642 (16)C10—H10A0.9700
O2—C71.2186 (17)C10—H10B0.9700
O3—C111.1949 (18)C12—C131.478 (2)
O4—C111.3157 (18)C12—H12A0.9700
O4—C121.4449 (18)C12—H12B0.9700
O5—C171.3616 (15)C13—H13A0.9600
O5—C201.4164 (17)C13—H13B0.9600
C1—C21.327 (3)C13—H13C0.9600
C1—H1A0.9300C14—C191.3776 (18)
C2—C31.413 (2)C14—C151.3842 (18)
C2—H2A0.9300C15—C161.3710 (19)
C3—C41.344 (2)C15—H15A0.9300
C3—H3A0.9300C16—C171.3791 (18)
C4—C51.4367 (19)C16—H16A0.9300
C5—C61.343 (2)C17—C181.3820 (17)
C5—C101.5015 (18)C18—C191.3801 (18)
C6—C71.448 (2)C18—H18A0.9300
C6—H6A0.9300C19—H19A0.9300
C7—C81.5133 (19)C20—C211.489 (2)
C8—C111.5090 (19)C20—H20A0.9700
C8—C91.5334 (18)C20—H20B0.9700
C8—H8A0.9800C21—H21A0.9600
C9—C141.5095 (17)C21—H21B0.9600
C9—C101.5204 (18)C21—H21C0.9600
C1—O1—C4106.29 (13)O4—C11—C8109.97 (12)
C11—O4—C12117.70 (13)O4—C12—C13109.51 (13)
C17—O5—C20117.53 (10)O4—C12—H12A109.8
C2—C1—O1110.96 (14)C13—C12—H12A109.8
C2—C1—H1A124.5O4—C12—H12B109.8
O1—C1—H1A124.5C13—C12—H12B109.8
C1—C2—C3106.45 (15)H12A—C12—H12B108.2
C1—C2—H2A126.8C12—C13—H13A109.5
C3—C2—H2A126.8C12—C13—H13B109.5
C4—C3—C2106.68 (15)H13A—C13—H13B109.5
C4—C3—H3A126.7C12—C13—H13C109.5
C2—C3—H3A126.7H13A—C13—H13C109.5
C3—C4—O1109.60 (12)H13B—C13—H13C109.5
C3—C4—C5133.38 (13)C19—C14—C15117.27 (11)
O1—C4—C5117.00 (13)C19—C14—C9122.46 (11)
C6—C5—C4121.59 (12)C15—C14—C9120.24 (11)
C6—C5—C10121.65 (12)C16—C15—C14121.73 (12)
C4—C5—C10116.75 (12)C16—C15—H15A119.1
C5—C6—C7122.71 (12)C14—C15—H15A119.1
C5—C6—H6A118.6C15—C16—C17120.16 (12)
C7—C6—H6A118.6C15—C16—H16A119.9
O2—C7—C6122.59 (13)C17—C16—H16A119.9
O2—C7—C8121.33 (13)O5—C17—C16116.00 (11)
C6—C7—C8115.95 (12)O5—C17—C18124.71 (11)
C11—C8—C7111.43 (11)C16—C17—C18119.28 (11)
C11—C8—C9110.98 (11)C19—C18—C17119.55 (12)
C7—C8—C9110.55 (11)C19—C18—H18A120.2
C11—C8—H8A107.9C17—C18—H18A120.2
C7—C8—H8A107.9C14—C19—C18122.01 (12)
C9—C8—H8A107.9C14—C19—H19A119.0
C14—C9—C10114.30 (10)C18—C19—H19A119.0
C14—C9—C8112.04 (10)O5—C20—C21107.84 (12)
C10—C9—C8107.80 (10)O5—C20—H20A110.1
C14—C9—H9A107.5C21—C20—H20A110.1
C10—C9—H9A107.5O5—C20—H20B110.1
C8—C9—H9A107.5C21—C20—H20B110.1
C5—C10—C9111.80 (11)H20A—C20—H20B108.5
C5—C10—H10A109.3C20—C21—H21A109.5
C9—C10—H10A109.3C20—C21—H21B109.5
C5—C10—H10B109.3H21A—C21—H21B109.5
C9—C10—H10B109.3C20—C21—H21C109.5
H10A—C10—H10B107.9H21A—C21—H21C109.5
O3—C11—O4125.33 (13)H21B—C21—H21C109.5
O3—C11—C8124.65 (14)
C4—O1—C1—C20.19 (19)C8—C9—C10—C5−52.86 (14)
O1—C1—C2—C30.2 (2)C12—O4—C11—O38.9 (2)
C1—C2—C3—C4−0.55 (18)C12—O4—C11—C8−168.69 (12)
C2—C3—C4—O10.68 (16)C7—C8—C11—O368.81 (17)
C2—C3—C4—C5−177.72 (14)C9—C8—C11—O3−54.86 (17)
C1—O1—C4—C3−0.55 (16)C7—C8—C11—O4−113.62 (13)
C1—O1—C4—C5178.14 (13)C9—C8—C11—O4122.71 (12)
C3—C4—C5—C6179.29 (15)C11—O4—C12—C1383.8 (2)
O1—C4—C5—C60.99 (19)C10—C9—C14—C1958.90 (16)
C3—C4—C5—C100.3 (2)C8—C9—C14—C19−64.11 (16)
O1—C4—C5—C10−177.97 (11)C10—C9—C14—C15−123.20 (13)
C4—C5—C6—C7−175.17 (13)C8—C9—C14—C15113.80 (14)
C10—C5—C6—C73.7 (2)C19—C14—C15—C160.0 (2)
C5—C6—C7—O2−179.68 (15)C9—C14—C15—C16−178.05 (13)
C5—C6—C7—C84.3 (2)C14—C15—C16—C17−0.1 (2)
O2—C7—C8—C1123.0 (2)C20—O5—C17—C16172.14 (13)
C6—C7—C8—C11−160.97 (12)C20—O5—C17—C18−8.22 (19)
O2—C7—C8—C9146.87 (14)C15—C16—C17—O5179.78 (13)
C6—C7—C8—C9−37.06 (17)C15—C16—C17—C180.1 (2)
C11—C8—C9—C14−48.49 (15)O5—C17—C18—C19−179.55 (13)
C7—C8—C9—C14−172.65 (11)C16—C17—C18—C190.1 (2)
C11—C8—C9—C10−175.09 (11)C15—C14—C19—C180.2 (2)
C7—C8—C9—C1060.74 (14)C9—C14—C19—C18178.21 (12)
C6—C5—C10—C921.98 (18)C17—C18—C19—C14−0.3 (2)
C4—C5—C10—C9−159.07 (11)C17—O5—C20—C21−174.37 (14)
C14—C9—C10—C5−178.13 (10)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C3—H3A···O3i0.932.553.441 (2)160
C6—H6A···O10.932.422.761 (2)102
C19—H19A···Cgii0.932.823.641 (2)147
C21—H21A···Cgiii0.962.943.546 (3)122
Symmetry codes: (i) x−1/2, −y+1/2, z−1/2; (ii) x+1, y, z; (iii) −x+3/2, y−1/2, −z+1/2.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C3—H3A···O3i0.932.553.441 (2)160
C6—H6A···O10.932.422.761 (2)102
C19—H19A···Cgii0.932.823.641 (2)147
C21—H21A···Cgiii0.962.943.546 (3)122
Symmetry codes: (i) x−1/2, −y+1/2, z−1/2; (ii) x+1, y, z; (iii) −x+3/2, y−1/2, −z+1/2.
Acknowledgements top

A. Badshah is grateful to the Higher Education Commission of Pakistan for the grant of PhD scholarship.

references
References top

Eddington, N. D., Cox, D. S., Roberts, R. R., Stables, J. P., Powell, C. B. & Scott, A. R. (2000). Curr. Med. Chem. 7, 417–436.

Li, J. Y. & Strobel, G. A. (2001). Phytochemistry, 57, 261–265.

Luu, B., Aguilar, J. L. G. D. & Junges, C. G. (2000). Molecules, 5, 1439–1460.

Macrae, C. F., Edgington, P. R., McCabe, P., Pidcoock, E., Shields, G. P., Taylor, R., Towler, M. & Van de Streek, J. (2006). J. Appl. Cryst. 39, 453–457.

Padmavathi, V., Reddy, B. J. M., Balaiah, A., Reddy, K. V. & Reddy, D. B. (2000). Molecules, 5, 1281–1286.

Padmavathi, V., Sharmila, K., Reddy, A. S. & Reddy, D. B. (2001). Indian J. Chem. Sect. B, 40, 11–14.

Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122.

Siemens (1999). XSCANS. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.