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Acta Crystallogr Sect E Struct Rep Online. 2010 August 1; 66(Pt 8): o1910.
Published online 2010 July 3. doi:  10.1107/S1600536810025018
PMCID: PMC3007213

Diethyl 4-hy­droxy-4-methyl-6-oxo-2-phenyl­cyclo­hexane-1,3-dicarboxyl­ate

Abstract

In the title mol­ecule, C19H24O6, the cyclo­hexa­none ring adopts a chair conformation. The dihedral angle between the phenyl ring and the best plane through the six atoms of the cyclo­hexa­none ring is 89.68 (7)°. In the crystal structure, mol­ecules are linked via pairs of inter­molecular O—H(...)O hydrogen bonds into centrosymmetric dimers and these dimers are connected by C—H(...)O inter­actions into columns down the a axis.

Related literature

For the applications of phenyl­cylcohexane, see: Adly et al. (2004 [triangle]); Pohl et al. (1977 [triangle]); Chu et al. (2005 [triangle]). For ring conformations, see: Cremer & Pople (1975 [triangle]). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986 [triangle]).

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Object name is e-66-o1910-scheme1.jpg

Experimental

Crystal data

  • C19H24O6
  • M r = 348.38
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o1910-efi1.jpg
  • a = 5.792 (2) Å
  • b = 15.766 (6) Å
  • c = 20.031 (7) Å
  • β = 98.531 (10)°
  • V = 1808.9 (11) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.10 mm−1
  • T = 100 K
  • 0.40 × 0.10 × 0.06 mm

Data collection

  • Bruker APEXII DUO CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2009 [triangle]) T min = 0.963, T max = 0.994
  • 37474 measured reflections
  • 5256 independent reflections
  • 3644 reflections with I > 2σ(I)
  • R int = 0.075

Refinement

  • R[F 2 > 2σ(F 2)] = 0.048
  • wR(F 2) = 0.122
  • S = 1.05
  • 5256 reflections
  • 233 parameters
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.33 e Å−3
  • Δρmin = −0.23 e Å−3

Data collection: APEX2 (Bruker, 2009 [triangle]); cell refinement: SAINT (Bruker, 2009 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810025018/bt5276sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810025018/bt5276Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

HKF and MH thank the Malaysian Government and Universiti Sains Malaysia for the Research University Golden Goose grant No. 1001/PFIZIK/811012. MH also thanks Universiti Sains Malaysia for a post-doctoral research fellowship. AMI is grateful to the Head of the Department of Chemistry and the Director, National Institute of Technology-Karnataka, India, for providing the research facilities and for their encouragement. AMI also thanks USM for a partially sponsored research visit to the X-ray Crystallography Unit, School of Physics, USM.

supplementary crystallographic information

Comment

Phenylcyclohexane is a highly valued chemical compound widely used as plasticizer in plastics, coatings and adhesive fields. It is also utilized as a penetrating agent. 5-Phenyl-cyclohexane-1,3-dione-4- carboxanilide is used as a stabilizer for double-base propellant and gives good results with the stability test (Adly et al., 2004). Many substituted phenylcyclohexane derivatives have shown liquid crystal properties (Pohl et al., 1977). Phenylcyclohexane derivatives are also biologically important. Linear pentapeptides (Penta-cis-Apc-DPhe-Arg-Trp-Gly-NH2) containing 1-amino-4-phenylcyclohexane-1-carboxylic acid (cis-Apc) and substituted Apc are potent hMC4R agonists and they are inactive or weakly active in hMC1R, hMC3R, and hMC5R agonist assays (Chu et al., 2005). Keeping in view of the importance of the phenylcyclohexane derivatives, the title compound (I) was synthesized.

The molecular structure of (I), is shown in Fig. 1. The cyclohexanone ring adopts a chair conformation with puckering parameters (Cremer & Pople, 1975) Q = 0.5606 (14) Å, Θ = 172.71 (14)° and [var phi] = 207.8 (11)°. The dihedral angle between the phenyl ring and the best plane through the six atoms of the cyclohexanone ring is 89.68 (7)°. In the crystal structure, Fig 2, adjacent molecules are linked via intermolecular O—H···O hydrogen bonds to centrosymmetric dimers. The dimers are connected by O6—H1O6···O1, C1—H1A···O3, C8—H8A···O3, C12—H12A···O2 and C19—H19C···O6 interactions (Table 1) into columns down the a axis.

Experimental

Ethylacetoacetate (19.1 ml, 0.15 mol) and piperidine (9 ml) were dissolved in 150 ml of dry benzene. Then benzaldehyde (15.3 ml, 0.15 mol) was added drop-wise at room temperature over 20 min. The reaction mixture was slowly brought to boil and refluxed for 2 hours with constant stirring with periodic TLC monitoring. After cooling, organic layer was washed with cold aqueous 10 % sodium carbonate, water and 5 % acetic acid. Then the organic layer was dried and evaporated under reduced pressure and the crude product synthesis of 2-benzylidene-malonic acid diethyl ester was purified by crystallization from methanol. Separately ethylacetoacetate (8 mmol) was dissolved in ethanol (10 ml) and sodium acetate (6 mmol) was dissolved in water (2 ml) and then slowly added to the ethanol solution at room temperature. The resulting solution was stirred for 10 minutes and then added the 2-benzylidene-malonic acid diethyl ester (3.2 mmol) slot-wise. The reaction mixture was stirred for 24 hrs at room temperature. The solid formed was filtered and washed with water and recrystalised in ethanol. (yield 40 %, m.p 510–512 K).

Refinement

The hydroxyl H atom was located from a difference Fourier map and refined freely. The remaining H atoms were positioned geometrically [C–H = 0.93–0.98 Å] and were refined using a riding model, with Uiso(H) = 1.2Ueq(C).

Figures

Fig. 1.
The asymmetric unit of the title compound, showing 50% probability displacement ellipsoids and the atom-numbering scheme.
Fig. 2.
The crystal packing of the title compound, viewed down the a axis, showing the columns of dimers down the a-axis. H atoms not involved in the hydrogen bond interactions are omitted for clarity.

Crystal data

C19H24O6F(000) = 744
Mr = 348.38Dx = 1.279 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 4276 reflections
a = 5.792 (2) Åθ = 2.4–25.6°
b = 15.766 (6) ŵ = 0.10 mm1
c = 20.031 (7) ÅT = 100 K
β = 98.531 (10)°Needle, colourless
V = 1808.9 (11) Å30.40 × 0.10 × 0.06 mm
Z = 4

Data collection

Bruker APEXII DUO CCD area-detector diffractometer5256 independent reflections
Radiation source: fine-focus sealed tube3644 reflections with I > 2σ(I)
graphiteRint = 0.075
[var phi] and ω scansθmax = 30.1°, θmin = 2.1°
Absorption correction: multi-scan (SADABS; Bruker, 2009)h = −8→8
Tmin = 0.963, Tmax = 0.994k = −22→22
37474 measured reflectionsl = −25→28

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.048Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.122H atoms treated by a mixture of independent and constrained refinement
S = 1.05w = 1/[σ2(Fo2) + (0.0484P)2 + 0.4474P] where P = (Fo2 + 2Fc2)/3
5256 reflections(Δ/σ)max < 0.001
233 parametersΔρmax = 0.33 e Å3
0 restraintsΔρmin = −0.23 e Å3

Special details

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.
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)

xyzUiso*/Ueq
O10.01230 (19)0.45072 (6)0.06556 (6)0.0303 (2)
O2−0.26845 (17)0.40000 (6)0.12086 (5)0.0264 (2)
O30.47676 (16)0.15467 (6)0.04607 (6)0.0272 (2)
O40.24998 (17)0.04265 (6)0.06139 (5)0.0249 (2)
O50.1168 (2)0.14395 (7)−0.08748 (6)0.0370 (3)
O60.03208 (17)0.36001 (7)−0.05989 (5)0.0249 (2)
C1−0.1446 (2)0.31138 (8)0.03806 (7)0.0188 (3)
H1A−0.28220.28170.04940.023*
C2−0.1754 (2)0.32386 (9)−0.03951 (7)0.0212 (3)
C3−0.1990 (2)0.23718 (9)−0.07382 (7)0.0247 (3)
H3A−0.34120.2101−0.06450.030*
H3B−0.21120.2447−0.12230.030*
C40.0059 (2)0.18060 (9)−0.04977 (7)0.0232 (3)
C50.0596 (2)0.17099 (8)0.02663 (7)0.0183 (3)
H5A−0.06620.13790.04170.022*
C60.0736 (2)0.25755 (8)0.06335 (7)0.0182 (3)
H6A0.21010.28780.05170.022*
C70.1109 (2)0.24444 (8)0.13937 (7)0.0195 (3)
C8−0.0573 (2)0.20405 (9)0.17164 (7)0.0240 (3)
H8A−0.19540.18520.14640.029*
C9−0.0195 (3)0.19190 (10)0.24098 (8)0.0296 (3)
H9A−0.13270.16510.26190.036*
C100.1857 (3)0.21942 (11)0.27934 (8)0.0328 (4)
H10A0.21050.21130.32580.039*
C110.3533 (3)0.25901 (11)0.24780 (8)0.0326 (4)
H11A0.49170.27740.27330.039*
C120.3165 (2)0.27152 (9)0.17833 (7)0.0251 (3)
H12A0.43050.29830.15770.030*
C13−0.1227 (2)0.39519 (9)0.07513 (7)0.0217 (3)
C14−0.2384 (3)0.47213 (10)0.16704 (8)0.0304 (3)
H14A−0.37970.48020.18690.036*
H14B−0.21170.52310.14220.036*
C15−0.0354 (3)0.45777 (11)0.22215 (9)0.0378 (4)
H15A−0.02920.50270.25470.057*
H15B0.10700.45690.20300.057*
H15C−0.05470.40450.24390.057*
C160.2866 (2)0.12288 (8)0.04565 (7)0.0191 (3)
C170.4559 (3)−0.00928 (10)0.08439 (8)0.0283 (3)
H17A0.59450.01840.07300.034*
H17B0.4407−0.06400.06210.034*
C180.4780 (4)−0.02101 (15)0.15860 (9)0.0539 (6)
H18A0.6084−0.05740.17350.081*
H18B0.3378−0.04630.16970.081*
H18C0.50220.03310.18060.081*
C19−0.3862 (2)0.37923 (10)−0.06405 (8)0.0275 (3)
H19A−0.40480.3838−0.11230.041*
H19B−0.36310.4347−0.04440.041*
H19C−0.52360.3541−0.05090.041*
H1O60.033 (5)0.422 (2)−0.0480 (14)0.106 (10)*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0355 (6)0.0239 (5)0.0336 (6)−0.0066 (4)0.0123 (5)−0.0006 (4)
O20.0255 (5)0.0263 (5)0.0293 (6)0.0004 (4)0.0102 (4)−0.0018 (4)
O30.0194 (5)0.0234 (5)0.0391 (6)−0.0008 (4)0.0051 (4)−0.0006 (4)
O40.0233 (5)0.0203 (5)0.0306 (6)0.0012 (4)0.0025 (4)0.0047 (4)
O50.0469 (7)0.0399 (7)0.0246 (6)0.0141 (5)0.0068 (5)−0.0014 (5)
O60.0225 (5)0.0263 (5)0.0267 (6)−0.0019 (4)0.0066 (4)0.0029 (4)
C10.0153 (6)0.0199 (6)0.0210 (7)−0.0006 (5)0.0017 (5)0.0017 (5)
C20.0172 (6)0.0231 (7)0.0226 (7)0.0010 (5)0.0003 (5)0.0032 (5)
C30.0253 (7)0.0254 (7)0.0215 (7)−0.0002 (5)−0.0029 (5)0.0021 (6)
C40.0261 (7)0.0204 (7)0.0226 (7)−0.0017 (5)0.0014 (5)0.0001 (5)
C50.0168 (6)0.0193 (6)0.0182 (6)−0.0006 (5)0.0011 (5)0.0016 (5)
C60.0159 (6)0.0186 (6)0.0200 (6)−0.0002 (5)0.0018 (5)0.0009 (5)
C70.0193 (6)0.0190 (6)0.0199 (7)0.0032 (5)0.0017 (5)0.0003 (5)
C80.0229 (7)0.0255 (7)0.0233 (7)0.0009 (5)0.0027 (5)0.0025 (6)
C90.0325 (8)0.0326 (8)0.0249 (8)0.0052 (6)0.0079 (6)0.0052 (6)
C100.0389 (9)0.0399 (9)0.0188 (7)0.0123 (7)0.0014 (6)0.0011 (7)
C110.0287 (8)0.0418 (9)0.0247 (8)0.0059 (6)−0.0048 (6)−0.0056 (7)
C120.0212 (6)0.0290 (7)0.0247 (7)0.0007 (5)0.0018 (5)−0.0032 (6)
C130.0199 (6)0.0221 (7)0.0232 (7)0.0026 (5)0.0037 (5)0.0040 (5)
C140.0346 (8)0.0249 (8)0.0334 (9)0.0059 (6)0.0106 (6)−0.0043 (6)
C150.0447 (10)0.0349 (9)0.0331 (9)0.0027 (7)0.0027 (7)−0.0063 (7)
C160.0217 (6)0.0189 (6)0.0163 (6)0.0005 (5)0.0020 (5)−0.0018 (5)
C170.0283 (7)0.0228 (7)0.0335 (8)0.0079 (6)0.0040 (6)0.0057 (6)
C180.0586 (12)0.0717 (14)0.0302 (10)0.0307 (11)0.0024 (9)0.0099 (9)
C190.0214 (7)0.0293 (8)0.0299 (8)0.0048 (6)−0.0021 (6)0.0048 (6)

Geometric parameters (Å, °)

O1—C131.2078 (17)C7—C81.3995 (19)
O2—C131.3369 (17)C8—C91.387 (2)
O2—C141.4599 (18)C8—H8A0.9300
O3—C161.2088 (16)C9—C101.386 (2)
O4—C161.3283 (17)C9—H9A0.9300
O4—C171.4634 (17)C10—C111.383 (2)
O5—C41.2088 (17)C10—H10A0.9300
O6—C21.4424 (17)C11—C121.390 (2)
O6—H1O61.01 (3)C11—H11A0.9300
C1—C131.512 (2)C12—H12A0.9300
C1—C61.5442 (18)C14—C151.506 (2)
C1—C21.5499 (19)C14—H14A0.9700
C1—H1A0.9800C14—H14B0.9700
C2—C191.5220 (19)C15—H15A0.9600
C2—C31.527 (2)C15—H15B0.9600
C3—C41.505 (2)C15—H15C0.9600
C3—H3A0.9700C17—C181.485 (2)
C3—H3B0.9700C17—H17A0.9700
C4—C51.5233 (19)C17—H17B0.9700
C5—C161.5168 (18)C18—H18A0.9600
C5—C61.5468 (19)C18—H18B0.9600
C5—H5A0.9800C18—H18C0.9600
C6—C71.5201 (19)C19—H19A0.9600
C6—H6A0.9800C19—H19B0.9600
C7—C121.3908 (19)C19—H19C0.9600
C13—O2—C14116.77 (11)C11—C10—C9119.38 (14)
C16—O4—C17117.13 (11)C11—C10—H10A120.3
C2—O6—H1O6106.9 (17)C9—C10—H10A120.3
C13—C1—C6108.32 (11)C10—C11—C12120.49 (14)
C13—C1—C2111.74 (11)C10—C11—H11A119.8
C6—C1—C2111.44 (11)C12—C11—H11A119.8
C13—C1—H1A108.4C11—C12—C7120.63 (14)
C6—C1—H1A108.4C11—C12—H12A119.7
C2—C1—H1A108.4C7—C12—H12A119.7
O6—C2—C19110.12 (11)O1—C13—O2123.86 (13)
O6—C2—C3104.43 (11)O1—C13—C1124.38 (12)
C19—C2—C3110.73 (12)O2—C13—C1111.76 (11)
O6—C2—C1110.92 (10)O2—C14—C15110.74 (12)
C19—C2—C1111.35 (11)O2—C14—H14A109.5
C3—C2—C1109.08 (11)C15—C14—H14A109.5
C4—C3—C2111.87 (11)O2—C14—H14B109.5
C4—C3—H3A109.2C15—C14—H14B109.5
C2—C3—H3A109.2H14A—C14—H14B108.1
C4—C3—H3B109.2C14—C15—H15A109.5
C2—C3—H3B109.2C14—C15—H15B109.5
H3A—C3—H3B107.9H15A—C15—H15B109.5
O5—C4—C3123.37 (13)C14—C15—H15C109.5
O5—C4—C5122.13 (13)H15A—C15—H15C109.5
C3—C4—C5114.48 (12)H15B—C15—H15C109.5
C16—C5—C4110.02 (11)O3—C16—O4124.81 (12)
C16—C5—C6109.83 (10)O3—C16—C5123.32 (12)
C4—C5—C6112.23 (11)O4—C16—C5111.88 (11)
C16—C5—H5A108.2O4—C17—C18109.29 (13)
C4—C5—H5A108.2O4—C17—H17A109.8
C6—C5—H5A108.2C18—C17—H17A109.8
C7—C6—C1113.02 (11)O4—C17—H17B109.8
C7—C6—C5110.25 (11)C18—C17—H17B109.8
C1—C6—C5110.26 (10)H17A—C17—H17B108.3
C7—C6—H6A107.7C17—C18—H18A109.5
C1—C6—H6A107.7C17—C18—H18B109.5
C5—C6—H6A107.7H18A—C18—H18B109.5
C12—C7—C8118.50 (13)C17—C18—H18C109.5
C12—C7—C6120.19 (12)H18A—C18—H18C109.5
C8—C7—C6121.30 (12)H18B—C18—H18C109.5
C9—C8—C7120.55 (13)C2—C19—H19A109.5
C9—C8—H8A119.7C2—C19—H19B109.5
C7—C8—H8A119.7H19A—C19—H19B109.5
C10—C9—C8120.45 (15)C2—C19—H19C109.5
C10—C9—H9A119.8H19A—C19—H19C109.5
C8—C9—H9A119.8H19B—C19—H19C109.5
C13—C1—C2—O666.12 (14)C1—C6—C7—C860.00 (16)
C6—C1—C2—O6−55.22 (14)C5—C6—C7—C8−63.89 (16)
C13—C1—C2—C19−56.89 (14)C12—C7—C8—C90.4 (2)
C6—C1—C2—C19−178.22 (11)C6—C7—C8—C9179.40 (13)
C13—C1—C2—C3−179.39 (11)C7—C8—C9—C10−0.2 (2)
C6—C1—C2—C359.27 (14)C8—C9—C10—C11−0.2 (2)
O6—C2—C3—C462.27 (14)C9—C10—C11—C120.3 (2)
C19—C2—C3—C4−179.24 (12)C10—C11—C12—C70.0 (2)
C1—C2—C3—C4−56.36 (15)C8—C7—C12—C11−0.3 (2)
C2—C3—C4—O5−128.63 (15)C6—C7—C12—C11−179.30 (13)
C2—C3—C4—C552.96 (16)C14—O2—C13—O1−8.1 (2)
O5—C4—C5—C169.17 (18)C14—O2—C13—C1170.78 (11)
C3—C4—C5—C16−172.40 (11)C6—C1—C13—O171.82 (17)
O5—C4—C5—C6131.79 (14)C2—C1—C13—O1−51.30 (17)
C3—C4—C5—C6−49.77 (15)C6—C1—C13—O2−107.10 (12)
C13—C1—C6—C756.26 (14)C2—C1—C13—O2129.77 (12)
C2—C1—C6—C7179.57 (11)C13—O2—C14—C15−78.28 (17)
C13—C1—C6—C5−179.85 (10)C17—O4—C16—O33.5 (2)
C2—C1—C6—C5−56.55 (14)C17—O4—C16—C5−176.62 (11)
C16—C5—C6—C7−61.15 (13)C4—C5—C16—O377.32 (16)
C4—C5—C6—C7176.13 (10)C6—C5—C16—O3−46.70 (17)
C16—C5—C6—C1173.38 (10)C4—C5—C16—O4−102.57 (13)
C4—C5—C6—C150.65 (14)C6—C5—C16—O4133.41 (12)
C1—C6—C7—C12−121.02 (14)C16—O4—C17—C18104.66 (16)
C5—C6—C7—C12115.09 (13)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O6—H1O6···O1i1.01 (3)2.05 (3)2.9958 (18)156 (2)
C1—H1A···O3ii0.982.443.323 (2)150
C8—H8A···O3ii0.932.603.493 (2)162
C12—H12A···O2iii0.932.563.468 (2)166
C19—H19C···O6ii0.962.553.396 (2)146

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: BT5276).

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