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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890

Ethyl (2Z)-3-oxo-2-(3,4,5-tri­meth­­oxy­benzyl­­idene)butano­ate

aDepartment of Chemistry, Universidade Federal de São Carlos, 13565-905 São Carlos, SP, Brazil, bInstituto de Química, Universidade Estadual de Campinas, CP 6154, 13083-970 Campinas, SP, Brazil, cDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia, and dChemistry Department, Faculty of Science, King Abdulaziz University, PO Box 80203 Jeddah, Saudi Arabia
*Correspondence e-mail: julio@power.ufscar.br

(Received 29 July 2013; accepted 19 August 2013; online 23 August 2013)

In the title compound, C16H20O6, the conformation about the C=C double bond [1.344 (2) Å] is Z. With respect to this bond, the ketone is almost coplanar [C—C—C—O torsion angle = −179.60 (10)°] and the ester is almost perpendicular [C—C—C—O = 78.42 (13)°]. The meth­oxy substituents of the central benzene ring are either almost coplanar [C—C—O—C = 3.54 (15) and 177.70 (9)°] or perpendicular [C—C—O—C = 80.08 12)° for the central substituent]. In the crystal, the three-dimensional architecture features C—H⋯O and ππ [inter-centroid distance = 3.6283 (6) Å] inter­actions.

Related literature

For background to the study, see: Rodrigues et al. (2004[Rodrigues, J. A. R., Moran, P. J. S., Conceicão, G. J. A. & Fardelone, L. C. (2004). Food Technol. Biotechnol. 42, 295-303.]); Zukerman-Schpector et al. (2011[Zukerman-Schpector, J., Abd Salim, S. N., Moran, P. J. S., Paula, B. R. S. de, Rodrigues, J. A. R. & Tiekink, E. R. T. (2011). Acta Cryst. E67, o1044.]). For the synthesis of the title compound, see: de Paula (2012[Paula, B. R. S. de (2012). MSc thesis, Universidade de Campinas, UNICAMP, Brazil.]).

[Scheme 1]

Experimental

Crystal data
  • C16H20O6

  • Mr = 308.32

  • Triclinic, [P \overline 1]

  • a = 8.3432 (4) Å

  • b = 10.2446 (5) Å

  • c = 10.4543 (5) Å

  • α = 61.130 (5)°

  • β = 77.450 (4)°

  • γ = 82.534 (4)°

  • V = 763.48 (7) Å3

  • Z = 2

  • Cu Kα radiation

  • μ = 0.86 mm−1

  • T = 100 K

  • 0.35 × 0.30 × 0.25 mm

Data collection
  • Agilent SuperNova (Dual, Cu at zero, Atlas) diffractometer

  • Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2013[Agilent (2013). CrysAlis PRO. Agilent Technologies, Santa Clara, CA, USA.]) Tmin = 0.631, Tmax = 1.000

  • 5294 measured reflections

  • 3101 independent reflections

  • 2943 reflections with I > 2σ(I)

  • Rint = 0.012

Refinement
  • R[F2 > 2σ(F2)] = 0.034

  • wR(F2) = 0.095

  • S = 1.05

  • 3101 reflections

  • 204 parameters

  • H-atom parameters constrained

  • Δρmax = 0.32 e Å−3

  • Δρmin = −0.25 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C12—H12b⋯O5i 0.97 2.47 3.4390 (16) 174
C14—H14a⋯O4ii 0.96 2.52 3.3295 (16) 142
C16—H16c⋯O2iii 0.96 2.55 3.4863 (15) 165
Symmetry codes: (i) -x, -y+1, -z; (ii) -x, -y+2, -z; (iii) -x+1, -y+1, -z+1.

Data collection: CrysAlis PRO (Agilent, 2013[Agilent (2013). CrysAlis PRO. Agilent Technologies, Santa Clara, CA, USA.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SIR92 (Altomare et al., 1999[Altomare, A., Burla, M. C., Camalli, M., Cascarano, G. L., Giacovazzo, C., Guagliardi, A., Moliterni, A. G. G., Polidori, G. & Spagna, R. (1999). J. Appl. Cryst. 32, 115-119.]); 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, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]), DIAMOND (Brandenburg, 2006[Brandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.]) and MarvinSketch (ChemAxon, 2010[ChemAxon (2010). Marvinsketch. http://www.chemaxon.com.]); software used to prepare material for publication: publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Comment top

As part of the continuing interest in the bio-reduction of α-haloketones and enones (Rodrigues et al., 2004; Zukerman-Schpector et al., 2011), the title compound, (I), was synthesized by means of a Knoevenagel condensation reaction between ethylacetoacetate and 3,4,5-trimethoxybenzaldehyde to afford a mixture of E and Z isomers that were separated by column chromatography (hexane/ethyl acetate, gradient from pure hexane to 95% hexane/5% ethyl acetate). The crystallized isomer, obtained by slow evaporation from a dichloromethane/hexane mixture, was shown by X-ray crystallography to be the Z isomer.

In (I), Fig. 1, the conformation about the C7C8 bond [1.3444 (15) Å] is Z. The O1–O3 methoxy groups are approximately planar, perpendicular and co-planar, respectively, with the benzene ring to which they are attached as seen in the C2—C3—O1—C14, C3—C4—O2—C15 and C4—C5—O3—C16 torsion angles of 3.54 (15), 80.08 (12) and 177.70 (9)°, respectively. With respect to the ethylene bond, the ketone group is co-planar [C7—C8—C9—O4 = -179.60 (10)°] but the ester is almost perpendicular [C7—C8—C11—O6 = 78.42 (13)°]. With the exception of the ester-carbonyl-O5 atom, the two perpendicularly orientated groups lie to the same side of the central plane.

In the crystal packing, C—H···O, Table 1, and ππ [inter-centroid distance = 3.6283 (6) Å for symmetry operation: 1 - x, 2 - y, -z] combine to link molecules into a three-dimensional architecture. Globally, molecule pack in layers in an ···ABA···fashion running parallel to the (2,0,-1) lattice planes, Fig. 2.

Related literature top

For background to the study, see: Rodrigues et al. (2004); Zukerman-Schpector et al. (2011). For the synthesis of the title compound, see: de Paula (2012).

Experimental top

The description of the synthesis of compound (I) together with spectra and HRMS analyses can be found in de Paula (2012); M.pt: 381.2—381.7 K.

Refinement top

Carbon-bound H-atoms were placed in calculated positions (C—H = 0.93 to 0.97 Å) and were included in the refinement in the riding model approximation, with Uiso(H) = 1.2Ueq(C) and 1.5Ueq(methyl-C).

Computing details top

Data collection: CrysAlis PRO (Agilent, 2013); cell refinement: CrysAlis PRO (Agilent, 2013); data reduction: CrysAlis PRO (Agilent, 2013); program(s) used to solve structure: SIR92 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012), DIAMOND (Brandenburg, 2006) and MarvinSketch (ChemAxon, 2010); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The molecular structure of compound (I) showing the atom-labelling scheme and displacement ellipsoids at the 70% probability level.
[Figure 2] Fig. 2. View in projection down the b axis of the unit-cell contents of (I). The ππ and C—H···O interactions are shown as purple and orange dashed lines, respectively.
Ethyl (2Z)-3-oxo-2-(3,4,5-trimethoxybenzylidene)butanoate top
Crystal data top
C16H20O6Z = 2
Mr = 308.32F(000) = 328
Triclinic, P1Dx = 1.341 Mg m3
Hall symbol: -P 1Melting point = 381.2–381.7 K
a = 8.3432 (4) ÅCu Kα radiation, λ = 1.54184 Å
b = 10.2446 (5) ÅCell parameters from 3721 reflections
c = 10.4543 (5) Åθ = 5.1–75.8°
α = 61.130 (5)°µ = 0.86 mm1
β = 77.450 (4)°T = 100 K
γ = 82.534 (4)°Irregular, colourless
V = 763.48 (7) Å30.35 × 0.30 × 0.25 mm
Data collection top
Agilent SuperNova (Dual, Cu at zero, Atlas)
diffractometer
3101 independent reflections
Radiation source: fine-focus sealed tube2943 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.012
Detector resolution: 10.4041 pixels mm-1θmax = 76.0°, θmin = 5.1°
ω scansh = 108
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2013)
k = 1212
Tmin = 0.631, Tmax = 1.000l = 1312
5294 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)] = 0.034Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.095H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0524P)2 + 0.2494P]
where P = (Fo2 + 2Fc2)/3
3101 reflections(Δ/σ)max < 0.001
204 parametersΔρmax = 0.32 e Å3
0 restraintsΔρmin = 0.25 e Å3
Crystal data top
C16H20O6γ = 82.534 (4)°
Mr = 308.32V = 763.48 (7) Å3
Triclinic, P1Z = 2
a = 8.3432 (4) ÅCu Kα radiation
b = 10.2446 (5) ŵ = 0.86 mm1
c = 10.4543 (5) ÅT = 100 K
α = 61.130 (5)°0.35 × 0.30 × 0.25 mm
β = 77.450 (4)°
Data collection top
Agilent SuperNova (Dual, Cu at zero, Atlas)
diffractometer
3101 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2013)
2943 reflections with I > 2σ(I)
Tmin = 0.631, Tmax = 1.000Rint = 0.012
5294 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0340 restraints
wR(F2) = 0.095H-atom parameters constrained
S = 1.05Δρmax = 0.32 e Å3
3101 reflectionsΔρmin = 0.25 e Å3
204 parameters
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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
O10.40766 (10)1.13778 (8)0.21253 (9)0.01963 (18)
O20.49401 (9)0.85742 (8)0.39679 (8)0.01745 (18)
O30.43618 (10)0.62786 (8)0.36141 (8)0.01846 (18)
O40.01540 (10)0.84612 (9)0.28318 (9)0.02070 (19)
O50.21960 (10)0.62520 (9)0.04434 (9)0.02128 (19)
O60.00196 (9)0.68398 (8)0.08761 (8)0.01854 (18)
C10.27109 (12)0.93633 (12)0.04388 (11)0.0146 (2)
C20.29899 (13)1.05493 (11)0.06585 (12)0.0157 (2)
H20.26871.15160.00100.019*
C30.37188 (13)1.02961 (12)0.18421 (12)0.0155 (2)
C40.41592 (12)0.88409 (12)0.28284 (11)0.0150 (2)
C50.38756 (13)0.76540 (12)0.26071 (11)0.0150 (2)
C60.31599 (13)0.79048 (11)0.14221 (11)0.0154 (2)
H60.29790.71100.12820.019*
C70.19873 (13)0.97298 (12)0.08589 (11)0.0153 (2)
H70.19531.07380.15380.018*
C80.13656 (13)0.88232 (12)0.12120 (11)0.0154 (2)
C90.07048 (13)0.93638 (12)0.26035 (12)0.0165 (2)
C100.07124 (14)1.10044 (13)0.36880 (12)0.0202 (2)
H10A0.00351.15340.32500.030*
H10B0.03771.11580.45740.030*
H10C0.18001.13660.39310.030*
C110.12582 (13)0.71652 (12)0.02458 (12)0.0160 (2)
C120.02291 (16)0.52685 (12)0.19624 (13)0.0229 (2)
H12A0.08310.47710.21470.027*
H12B0.07860.47730.16000.027*
C130.12367 (17)0.52221 (14)0.33569 (14)0.0299 (3)
H13A0.06750.57220.36990.045*
H13B0.13970.42030.41050.045*
H13C0.22840.57120.31600.045*
C140.35859 (15)1.28797 (12)0.11817 (13)0.0206 (2)
H14A0.24151.29460.12510.031*
H14B0.41051.31620.01740.031*
H14C0.39091.35370.14880.031*
C150.38159 (15)0.85960 (13)0.52181 (12)0.0225 (2)
H15A0.30990.77690.56670.034*
H15B0.31750.95120.48870.034*
H15C0.44240.85220.59320.034*
C160.40407 (16)0.50278 (12)0.34655 (13)0.0224 (2)
H16A0.46620.50970.25480.034*
H16B0.28900.50200.34700.034*
H16C0.43540.41250.42790.034*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0258 (4)0.0150 (4)0.0227 (4)0.0009 (3)0.0105 (3)0.0103 (3)
O20.0190 (4)0.0215 (4)0.0152 (4)0.0011 (3)0.0063 (3)0.0103 (3)
O30.0262 (4)0.0133 (4)0.0173 (4)0.0027 (3)0.0109 (3)0.0062 (3)
O40.0226 (4)0.0245 (4)0.0189 (4)0.0029 (3)0.0050 (3)0.0122 (3)
O50.0254 (4)0.0182 (4)0.0237 (4)0.0029 (3)0.0066 (3)0.0124 (3)
O60.0205 (4)0.0147 (4)0.0180 (4)0.0011 (3)0.0032 (3)0.0056 (3)
C10.0137 (5)0.0164 (5)0.0140 (5)0.0005 (4)0.0028 (4)0.0074 (4)
C20.0161 (5)0.0140 (5)0.0160 (5)0.0013 (4)0.0039 (4)0.0062 (4)
C30.0153 (5)0.0160 (5)0.0168 (5)0.0009 (4)0.0018 (4)0.0093 (4)
C40.0142 (5)0.0187 (5)0.0136 (5)0.0005 (4)0.0039 (4)0.0083 (4)
C50.0152 (5)0.0146 (5)0.0135 (5)0.0014 (4)0.0030 (4)0.0055 (4)
C60.0173 (5)0.0151 (5)0.0158 (5)0.0001 (4)0.0042 (4)0.0084 (4)
C70.0161 (5)0.0145 (5)0.0136 (5)0.0017 (4)0.0033 (4)0.0056 (4)
C80.0156 (5)0.0161 (5)0.0137 (5)0.0015 (4)0.0029 (4)0.0069 (4)
C90.0148 (5)0.0211 (5)0.0145 (5)0.0008 (4)0.0023 (4)0.0095 (4)
C100.0242 (6)0.0209 (5)0.0157 (5)0.0013 (4)0.0077 (4)0.0075 (4)
C110.0183 (5)0.0174 (5)0.0163 (5)0.0000 (4)0.0077 (4)0.0091 (4)
C120.0308 (6)0.0144 (5)0.0215 (6)0.0050 (4)0.0061 (5)0.0054 (4)
C130.0343 (7)0.0240 (6)0.0234 (6)0.0062 (5)0.0003 (5)0.0056 (5)
C140.0254 (6)0.0139 (5)0.0244 (6)0.0007 (4)0.0072 (4)0.0097 (4)
C150.0297 (6)0.0238 (6)0.0158 (5)0.0010 (5)0.0029 (4)0.0110 (5)
C160.0350 (6)0.0140 (5)0.0201 (5)0.0014 (4)0.0129 (5)0.0067 (4)
Geometric parameters (Å, º) top
C1—C21.3962 (15)C11—O51.2068 (13)
C1—C61.4030 (14)C11—O61.3397 (13)
C1—C71.4667 (14)C12—O61.4605 (13)
C2—C31.3944 (15)C12—C131.4984 (17)
C2—H20.9300C12—H12A0.9700
C3—O11.3586 (13)C12—H12B0.9700
C3—C41.3995 (14)C13—H13A0.9600
C4—O21.3765 (12)C13—H13B0.9600
C4—C51.3993 (15)C13—H13C0.9600
C5—O31.3649 (12)C14—O11.4332 (13)
C5—C61.3898 (15)C14—H14A0.9600
C6—H60.9300C14—H14B0.9600
C7—C81.3444 (15)C14—H14C0.9600
C7—H70.9300C15—O21.4418 (13)
C8—C91.4893 (14)C15—H15A0.9600
C8—C111.5022 (14)C15—H15B0.9600
C9—O41.2224 (14)C15—H15C0.9600
C9—C101.5066 (15)C16—O31.4274 (13)
C10—H10A0.9600C16—H16A0.9600
C10—H10B0.9600C16—H16B0.9600
C10—H10C0.9600C16—H16C0.9600
C2—C1—C6119.68 (9)O6—C11—C8110.49 (9)
C2—C1—C7117.10 (9)O6—C12—C13106.84 (9)
C6—C1—C7123.19 (9)O6—C12—H12A110.4
C3—C2—C1120.53 (9)C13—C12—H12A110.4
C3—C2—H2119.7O6—C12—H12B110.4
C1—C2—H2119.7C13—C12—H12B110.4
O1—C3—C2124.84 (9)H12A—C12—H12B108.6
O1—C3—C4115.31 (9)C12—C13—H13A109.5
C2—C3—C4119.84 (10)C12—C13—H13B109.5
O2—C4—C5119.72 (9)H13A—C13—H13B109.5
O2—C4—C3120.69 (9)C12—C13—H13C109.5
C5—C4—C3119.51 (9)H13A—C13—H13C109.5
O3—C5—C6123.90 (9)H13B—C13—H13C109.5
O3—C5—C4115.35 (9)O1—C14—H14A109.5
C6—C5—C4120.74 (10)O1—C14—H14B109.5
C5—C6—C1119.69 (10)H14A—C14—H14B109.5
C5—C6—H6120.2O1—C14—H14C109.5
C1—C6—H6120.2H14A—C14—H14C109.5
C8—C7—C1129.55 (10)H14B—C14—H14C109.5
C8—C7—H7115.2O2—C15—H15A109.5
C1—C7—H7115.2O2—C15—H15B109.5
C7—C8—C9123.31 (10)H15A—C15—H15B109.5
C7—C8—C11123.66 (9)O2—C15—H15C109.5
C9—C8—C11113.03 (9)H15A—C15—H15C109.5
O4—C9—C8118.94 (10)H15B—C15—H15C109.5
O4—C9—C10121.50 (9)O3—C16—H16A109.5
C8—C9—C10119.56 (9)O3—C16—H16B109.5
C9—C10—H10A109.5H16A—C16—H16B109.5
C9—C10—H10B109.5O3—C16—H16C109.5
H10A—C10—H10B109.5H16A—C16—H16C109.5
C9—C10—H10C109.5H16B—C16—H16C109.5
H10A—C10—H10C109.5C3—O1—C14117.31 (8)
H10B—C10—H10C109.5C4—O2—C15112.44 (8)
O5—C11—O6124.60 (10)C5—O3—C16117.32 (8)
O5—C11—C8124.91 (10)C11—O6—C12116.84 (9)
C6—C1—C2—C30.35 (16)C1—C7—C8—C111.85 (18)
C7—C1—C2—C3178.10 (9)C7—C8—C9—O4179.60 (10)
C1—C2—C3—O1178.28 (9)C11—C8—C9—O40.17 (14)
C1—C2—C3—C40.69 (16)C7—C8—C9—C100.22 (16)
O1—C3—C4—O21.71 (14)C11—C8—C9—C10179.55 (9)
C2—C3—C4—O2177.36 (9)C7—C8—C11—O5101.11 (13)
O1—C3—C4—C5178.50 (9)C9—C8—C11—O579.13 (13)
C2—C3—C4—C50.57 (16)C7—C8—C11—O678.42 (13)
O2—C4—C5—O32.47 (14)C9—C8—C11—O6101.35 (10)
C3—C4—C5—O3179.28 (9)C2—C3—O1—C143.54 (15)
O2—C4—C5—C6176.93 (9)C4—C3—O1—C14177.45 (9)
C3—C4—C5—C60.11 (16)C5—C4—O2—C15103.14 (11)
O3—C5—C6—C1179.57 (9)C3—C4—O2—C1580.08 (12)
C4—C5—C6—C10.22 (16)C6—C5—O3—C162.92 (15)
C2—C1—C6—C50.11 (15)C4—C5—O3—C16177.70 (9)
C7—C1—C6—C5178.46 (10)O5—C11—O6—C122.89 (15)
C2—C1—C7—C8168.73 (11)C8—C11—O6—C12176.64 (8)
C6—C1—C7—C812.88 (18)C13—C12—O6—C11157.95 (10)
C1—C7—C8—C9178.41 (10)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C12—H12b···O5i0.972.473.4390 (16)174
C14—H14a···O4ii0.962.523.3295 (16)142
C16—H16c···O2iii0.962.553.4863 (15)165
Symmetry codes: (i) x, y+1, z; (ii) x, y+2, z; (iii) x+1, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C12—H12b···O5i0.972.473.4390 (16)174
C14—H14a···O4ii0.962.523.3295 (16)142
C16—H16c···O2iii0.962.553.4863 (15)165
Symmetry codes: (i) x, y+1, z; (ii) x, y+2, z; (iii) x+1, y+1, z+1.
 

Acknowledgements

We thank the Brazilian agencies Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq: 306532/2009–3,to JZ-S), Coordenação de Aperfeicoamento de Pessoal de Nível Superior (CAPES: 808/09 to JZ-S and scholarship to CLH) and FAPESP for financial support. We also thank the Ministry of Higher Education (Malaysia) for funding structural studies through the High-Impact Research scheme (UM.C/HIR-MOHE/SC/03).

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