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Acta Crystallogr Sect E Struct Rep Online. 2009 June 1; 65(Pt 6): o1203.
Published online 2009 May 7. doi:  10.1107/S160053680901602X
PMCID: PMC2969590

Diethyl (1-hydr­oxy-1,2-diphenyl­ethyl)phospho­nate

Abstract

In the title compound, C18H23O4P, the dihedral angle between the aromatic ring planes is 69.94 (14)°. Both ethyl side chains are disordered over two sets of sites, with occupancy ratios of 80:20 and 70:30. In the crystal, inversion dimers linked by pairs of O—H(...)O hydrogen bonds occur, leading to R 2 1(8) loops, and C—H(...)O and weak C—H(...)π inter­actions are also seen.

Related literature

For related structures, see: Acar et al. (2009 [triangle]); Tahir et al. (2007 [triangle], 2009a [triangle],b [triangle]). For the synthesis, see: Texier-Boullet & Lequitte (1986 [triangle]). For graph-set notation, see: Bernstein et al. (1995 [triangle]).

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Object name is e-65-o1203-scheme1.jpg

Experimental

Crystal data

  • C18H23O4P
  • M r = 334.33
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-o1203-efi2.jpg
  • a = 23.8545 (11) Å
  • b = 10.6663 (5) Å
  • c = 18.4994 (14) Å
  • β = 129.451 (2)°
  • V = 3634.6 (4) Å3
  • Z = 8
  • Mo Kα radiation
  • μ = 0.17 mm−1
  • T = 296 K
  • 0.30 × 0.25 × 0.22 mm

Data collection

  • Bruker Kappa APEXII CCD diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2005 [triangle]) T min = 0.953, T max = 0.968
  • 18572 measured reflections
  • 4354 independent reflections
  • 2742 reflections with I > 2σ(I)
  • R int = 0.031

Refinement

  • R[F 2 > 2σ(F 2)] = 0.065
  • wR(F 2) = 0.198
  • S = 1.05
  • 4354 reflections
  • 217 parameters
  • 8 restraints
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.73 e Å−3
  • Δρmin = −0.63 e Å−3

Data collection: APEX2 (Bruker, 2007 [triangle]); cell refinement: SAINT (Bruker, 2007 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 (Farrugia, 1997 [triangle]) and PLATON (Spek, 2009 [triangle]); software used to prepare material for publication: WinGX (Farrugia, 1999 [triangle]) and PLATON.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S160053680901602X/hb2959sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S160053680901602X/hb2959Isup2.hkl

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

Acknowledgments

The authors acknowledge the Higher Education Commission, Islamabad, Pakistan, and Bana International, Karachi, Pakistan, for funding the purchase of the diffractometer and for technical support, respectively.

supplementary crystallographic information

Comment

We have reported the preparation and crystal structures of the phosphonate compounds (Acar et al., 2009; Tahir et al., 2007, 2009a, 2009b). In continuation to the study of phosphonate compounds, we, herein report the preparation and crystal structure of the title compound (I), (Fig. 1).

The crystal structures of (II) Dimethyl (1-hydroxy-1,2-diphenylethyl)phosphonate (Acar et al., 2009) has been reported which differs from (I) due to dimethylphosphonate instead of diethylphosphonate. In the title compound ethyl moieties of diethylphosphonate are disordered over two sites with occupancy ratios of 80:20 and 70:30, respectively. The disorder in diethyl moieties is also present in the reported structure (Tahir et al., 2009a). The present compound is basically dimerized forming ring motifs R22(10) (Bernstein et al., 1995) due to O—H···O type of intermolecular H-bonding (Fig. 2). The title molecule is also stabilized due to intermolecular H-bonding of C—H···O type and C—H···CgA interaction (Table 1), Where CgA is the centroid of the aromatic ring A (C9–C14). Ring motifs of R21(8) are also present which are formed due to the intermolecular H-bondings (Fig. 2). The dihedral angle between the ring A and the benzene ring B (C1–C6) is 69.94 (14)°.

Experimental

The title compound was prepared according to method described by Texier-Boullet & Lequitte (1986). In a solution mixture of 2-phenylacetophenone (3.92 g, 20 mmol) and diethylphosphonate (2.76 g, 20 mmol), a mixture of KF (5 g, 86.20 mmol) and commercial Al2O3 (5 g, 49 mmol) was slowly added at 273 K. The reaction mixture remained at room temperature for two days. The product was extracted twice with CH3Cl2. The extracted product was recrystallized in a mixture of distalled water and ethyl alcohol to yield colourless prisms of (I).

Refinement

The coordinates of H-atom of hydroxy group were refined. C-bound H atoms were positioned geometrically, with C-H = 0.93, 0.96 and 0.97 Å for aromatic, methyl and ethylene moieties 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.

Figures

Fig. 1.
View of (I) showing 30% displacement ellipoids (H-atoms are shown by small spheres of arbitrary radius). The ethyl moieties of smaller occupancy factor are not shown for clarity.
Fig. 2.
Detail of (I) showing the formation of dimers through hydrogen bonding forming R22(10) motifs.

Crystal data

C18H23O4PF(000) = 1424
Mr = 334.33Dx = 1.220 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 4354 reflections
a = 23.8545 (11) Åθ = 2.2–27.9°
b = 10.6663 (5) ŵ = 0.17 mm1
c = 18.4994 (14) ÅT = 296 K
β = 129.451 (2)°Prism, colourless
V = 3634.6 (4) Å30.30 × 0.25 × 0.22 mm
Z = 8

Data collection

Bruker Kappa APEXII CCD diffractometer4354 independent reflections
Radiation source: fine-focus sealed tube2742 reflections with I > 2σ(I)
graphiteRint = 0.031
Detector resolution: 7.50 pixels mm-1θmax = 27.9°, θmin = 2.2°
ω scansh = −27→31
Absorption correction: multi-scan (SADABS; Bruker, 2005)k = −13→14
Tmin = 0.953, Tmax = 0.968l = −23→24
18572 measured reflections

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)] = 0.065Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.198H atoms treated by a mixture of independent and constrained refinement
S = 1.05w = 1/[σ2(Fo2) + (0.0851P)2 + 3.8003P] where P = (Fo2 + 2Fc2)/3
4354 reflections(Δ/σ)max < 0.001
217 parametersΔρmax = 0.73 e Å3
8 restraintsΔρmin = −0.63 e Å3

Special details

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)

xyzUiso*/UeqOcc. (<1)
P10.23098 (5)0.51952 (7)0.48295 (5)0.0564 (3)
O10.24033 (11)0.65326 (19)0.37591 (14)0.0534 (7)
O20.17697 (15)0.4238 (2)0.47220 (16)0.0809 (10)
O30.29721 (15)0.4365 (2)0.51385 (17)0.0789 (9)
O40.25082 (14)0.62304 (19)0.54704 (14)0.0684 (8)
C10.17620 (15)0.4629 (3)0.30222 (18)0.0499 (9)
C20.1240 (2)0.3727 (3)0.2725 (2)0.0713 (12)
C30.1151 (2)0.2728 (4)0.2178 (3)0.0802 (14)
C40.1576 (2)0.2619 (3)0.1929 (2)0.0781 (14)
C50.2088 (2)0.3494 (4)0.2220 (3)0.0832 (16)
C60.21863 (19)0.4501 (3)0.2765 (2)0.0656 (12)
C70.18743 (15)0.5724 (3)0.36315 (18)0.0473 (8)
C80.11690 (18)0.6435 (3)0.3225 (2)0.0603 (11)
C90.08167 (17)0.7045 (3)0.2292 (2)0.0604 (11)
C100.1049 (2)0.8214 (3)0.2239 (2)0.0742 (11)
C110.0723 (2)0.8779 (4)0.1386 (3)0.0914 (14)
C120.0159 (3)0.8215 (4)0.0578 (3)0.1001 (16)
C13−0.0075 (2)0.7068 (5)0.0618 (3)0.0986 (18)
C140.02499 (19)0.6485 (4)0.1464 (3)0.0802 (14)
C15A0.1966 (3)0.3662 (6)0.5570 (4)0.1000 (17)0.800
C16A0.1312 (3)0.3721 (6)0.5486 (4)0.1000 (17)0.800
C17A0.3652 (4)0.4948 (10)0.5515 (7)0.130 (3)0.700
C18A0.4280 (4)0.4270 (8)0.6305 (6)0.130 (3)0.700
C17B0.3660 (8)0.434 (2)0.6034 (12)0.130 (3)0.300
C15B0.1434 (12)0.424 (2)0.5136 (14)0.1000 (17)0.200
C16B0.1959 (13)0.347 (2)0.5989 (15)0.1000 (17)0.200
C18B0.3938 (11)0.497 (3)0.5609 (19)0.130 (3)0.300
H10.241 (2)0.719 (4)0.403 (3)0.0799*
H60.254260.509430.295770.0793*
H8A0.082600.585370.315880.0722*
H8B0.127410.707610.366800.0722*
H20.094680.378880.289140.0847*
H30.079680.212710.198120.0963*
H40.151390.195010.156220.0936*
H50.238110.342050.205310.0991*
H140.008460.570230.147660.0964*
H15A0.236200.411560.611970.1200*0.800
H15B0.211440.279820.561950.1200*0.800
H16A0.116040.457830.541140.1500*0.800
H16B0.141650.338030.604070.1500*0.800
H16C0.093020.324400.495130.1500*0.800
H17A0.365680.579320.571300.1557*0.700
H17B0.369040.500980.502480.1557*0.700
H18A0.442890.463060.687930.1947*0.700
H18B0.467080.432780.628400.1947*0.700
H18C0.415400.340590.627380.1947*0.700
H100.142950.861680.278630.0893*
H110.088980.955400.136280.1095*
H12−0.006570.860580.000420.1191*
H13−0.045780.667590.006740.1182*
H15C0.095760.384700.472910.1200*0.200
H15D0.139030.507610.529460.1200*0.200
H16D0.175880.264560.590530.1500*0.200
H16E0.205060.386200.652100.1500*0.200
H16F0.240550.339170.609080.1500*0.200
H17C0.385300.350520.626700.1557*0.300
H17D0.369270.484140.649730.1557*0.300
H18D0.393930.439290.521260.1947*0.300
H18E0.442390.526190.609360.1947*0.300
H18F0.363250.567360.524310.1947*0.300

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
P10.0822 (6)0.0449 (4)0.0468 (4)−0.0038 (4)0.0432 (4)−0.0023 (3)
O10.0690 (13)0.0474 (11)0.0556 (11)−0.0050 (10)0.0452 (10)−0.0051 (9)
O20.122 (2)0.0731 (15)0.0634 (14)−0.0310 (14)0.0663 (15)−0.0082 (12)
O30.0938 (18)0.0634 (14)0.0675 (14)0.0183 (13)0.0456 (13)0.0055 (12)
O40.1092 (18)0.0490 (12)0.0520 (12)−0.0039 (12)0.0535 (12)−0.0053 (9)
C10.0603 (16)0.0497 (16)0.0407 (13)0.0008 (13)0.0326 (13)−0.0008 (11)
C20.078 (2)0.074 (2)0.069 (2)−0.0178 (18)0.0501 (18)−0.0185 (17)
C30.089 (3)0.071 (2)0.068 (2)−0.025 (2)0.044 (2)−0.0217 (18)
C40.097 (3)0.066 (2)0.058 (2)0.000 (2)0.043 (2)−0.0160 (16)
C50.097 (3)0.090 (3)0.082 (2)−0.004 (2)0.066 (2)−0.025 (2)
C60.077 (2)0.069 (2)0.068 (2)−0.0109 (17)0.0541 (18)−0.0174 (16)
C70.0609 (16)0.0482 (15)0.0432 (13)−0.0041 (13)0.0379 (13)−0.0029 (11)
C80.0692 (19)0.071 (2)0.0582 (17)0.0050 (16)0.0487 (16)0.0000 (15)
C90.0586 (18)0.071 (2)0.0551 (17)0.0118 (15)0.0378 (15)0.0033 (15)
C100.079 (2)0.066 (2)0.0573 (19)0.0130 (18)0.0338 (17)0.0025 (16)
C110.101 (3)0.071 (2)0.071 (2)0.013 (2)0.040 (2)0.0162 (19)
C120.102 (3)0.099 (3)0.060 (2)0.015 (3)0.033 (2)0.018 (2)
C130.076 (3)0.118 (4)0.057 (2)−0.003 (3)0.0213 (19)0.003 (2)
C140.066 (2)0.095 (3)0.067 (2)−0.007 (2)0.0364 (18)0.004 (2)
C15A0.125 (3)0.104 (3)0.091 (3)−0.004 (3)0.078 (3)0.017 (2)
C16A0.125 (3)0.104 (3)0.091 (3)−0.004 (3)0.078 (3)0.017 (2)
C17A0.084 (4)0.133 (4)0.136 (5)0.020 (4)0.053 (4)0.032 (3)
C18A0.084 (4)0.133 (4)0.136 (5)0.020 (4)0.053 (4)0.032 (3)
C17B0.084 (4)0.133 (4)0.136 (5)0.020 (4)0.053 (4)0.032 (3)
C15B0.125 (3)0.104 (3)0.091 (3)−0.004 (3)0.078 (3)0.017 (2)
C16B0.125 (3)0.104 (3)0.091 (3)−0.004 (3)0.078 (3)0.017 (2)
C18B0.084 (4)0.133 (4)0.136 (5)0.020 (4)0.053 (4)0.032 (3)

Geometric parameters (Å, °)

P1—O21.554 (4)C4—H40.9300
P1—O31.568 (4)C5—H50.9300
P1—O41.461 (2)C6—H60.9300
P1—C71.839 (3)C8—H8A0.9700
O1—C71.419 (5)C8—H8B0.9700
O2—C15A1.458 (7)C10—H100.9300
O2—C15B1.42 (3)C11—H110.9300
O3—C17A1.438 (12)C12—H120.9300
O3—C17B1.408 (19)C13—H130.9300
O1—H10.86 (4)C14—H140.9300
C1—C21.382 (6)C15A—H15A0.9700
C1—C71.524 (4)C15A—H15B0.9700
C1—C61.372 (6)C15B—H15C0.9700
C2—C31.390 (6)C15B—H15D0.9600
C3—C41.359 (8)C16A—H16A0.9600
C4—C51.348 (7)C16A—H16C0.9600
C5—C61.387 (6)C16A—H16B0.9600
C7—C81.537 (6)C16B—H16E0.9600
C8—C91.505 (4)C16B—H16D0.9700
C9—C141.378 (5)C16B—H16F0.9600
C9—C101.393 (5)C17A—H17A0.9700
C10—C111.378 (5)C17A—H17B0.9700
C11—C121.360 (6)C17B—H17C0.9700
C12—C131.366 (8)C17B—H17D0.9700
C13—C141.377 (6)C18A—H18A0.9600
C15A—C16A1.468 (12)C18A—H18B0.9600
C15B—C16B1.49 (3)C18A—H18C0.9600
C17A—C18A1.456 (14)C18B—H18D0.9600
C17B—C18B1.47 (4)C18B—H18E0.9600
C2—H20.9300C18B—H18F0.9600
C3—H30.9300
O2—P1—O3103.70 (16)C11—C10—H10120.00
O2—P1—O4114.51 (19)C10—C11—H11120.00
O2—P1—C7105.05 (15)C12—C11—H11120.00
O3—P1—O4113.52 (16)C11—C12—H12120.00
O3—P1—C7106.21 (17)C13—C12—H12120.00
O4—P1—C7112.93 (13)C12—C13—H13120.00
P1—O2—C15A117.8 (3)C14—C13—H13120.00
P1—O2—C15B129.6 (9)C9—C14—H14120.00
P1—O3—C17A119.8 (5)C13—C14—H14120.00
P1—O3—C17B126.2 (9)O2—C15A—H15A111.00
C7—O1—H1106 (4)O2—C15A—H15B111.00
C2—C1—C6118.0 (3)C16A—C15A—H15A111.00
C2—C1—C7121.2 (4)C16A—C15A—H15B111.00
C6—C1—C7120.7 (3)H15A—C15A—H15B109.00
C1—C2—C3120.4 (5)O2—C15B—H15D112.00
C2—C3—C4120.7 (4)C16B—C15B—H15C111.00
C3—C4—C5119.2 (4)O2—C15B—H15C111.00
C4—C5—C6121.2 (5)H15C—C15B—H15D110.00
C1—C6—C5120.5 (4)C16B—C15B—H15D112.00
P1—C7—O1102.96 (19)C15A—C16A—H16B110.00
P1—C7—C8110.2 (3)C15A—C16A—H16A110.00
O1—C7—C1108.0 (3)C15A—C16A—H16C110.00
P1—C7—C1110.8 (2)H16A—C16A—H16B109.00
C1—C7—C8113.1 (3)H16A—C16A—H16C109.00
O1—C7—C8111.3 (3)H16B—C16A—H16C109.00
C7—C8—C9114.5 (4)C15B—C16B—H16E110.00
C8—C9—C10120.7 (3)C15B—C16B—H16F110.00
C8—C9—C14121.7 (3)C15B—C16B—H16D110.00
C10—C9—C14117.6 (3)H16D—C16B—H16E109.00
C9—C10—C11120.8 (3)H16D—C16B—H16F109.00
C10—C11—C12120.6 (4)H16E—C16B—H16F110.00
C11—C12—C13119.3 (4)O3—C17A—H17A109.00
C12—C13—C14120.8 (4)O3—C17A—H17B109.00
C9—C14—C13120.9 (4)C18A—C17A—H17A109.00
O2—C15A—C16A106.0 (5)C18A—C17A—H17B109.00
O2—C15B—C16B101 (2)H17A—C17A—H17B108.00
O3—C17A—C18A113.3 (8)O3—C17B—H17C114.00
O3—C17B—C18B87.0 (15)C18B—C17B—H17D114.00
C1—C2—H2120.00O3—C17B—H17D114.00
C3—C2—H2120.00C18B—C17B—H17C114.00
C2—C3—H3120.00H17C—C17B—H17D111.00
C4—C3—H3120.00C17A—C18A—H18B110.00
C3—C4—H4120.00C17A—C18A—H18C109.00
C5—C4—H4120.00C17A—C18A—H18A109.00
C4—C5—H5119.00H18A—C18A—H18C109.00
C6—C5—H5119.00H18B—C18A—H18C110.00
C1—C6—H6120.00H18A—C18A—H18B109.00
C5—C6—H6120.00C17B—C18B—H18D110.00
C7—C8—H8A109.00C17B—C18B—H18E110.00
C7—C8—H8B109.00C17B—C18B—H18F110.00
C9—C8—H8A109.00H18D—C18B—H18E109.00
C9—C8—H8B109.00H18D—C18B—H18F109.00
H8A—C8—H8B108.00H18E—C18B—H18F109.00
C9—C10—H10120.00
O3—P1—O2—C15A69.5 (4)C2—C1—C7—O1−175.6 (3)
O4—P1—O2—C15A−54.7 (4)C2—C1—C7—C8−52.0 (4)
C7—P1—O2—C15A−179.2 (4)C6—C1—C7—P1−106.6 (3)
O2—P1—O3—C17A−165.6 (5)C6—C1—C7—O15.5 (4)
O4—P1—O3—C17A−40.8 (5)C6—C1—C7—C8129.1 (3)
C7—P1—O3—C17A83.9 (5)C1—C2—C3—C40.2 (6)
O2—P1—C7—O1−176.6 (2)C2—C3—C4—C50.0 (6)
O2—P1—C7—C1−61.4 (3)C3—C4—C5—C6−0.2 (6)
O2—P1—C7—C864.6 (3)C4—C5—C6—C10.0 (6)
O3—P1—C7—O1−67.1 (2)P1—C7—C8—C9172.9 (2)
O3—P1—C7—C148.1 (3)O1—C7—C8—C959.3 (3)
O3—P1—C7—C8174.1 (2)C1—C7—C8—C9−62.4 (4)
O4—P1—C7—O157.9 (3)C7—C8—C9—C10−83.0 (5)
O4—P1—C7—C1173.1 (3)C7—C8—C9—C1498.0 (5)
O4—P1—C7—C8−60.9 (3)C8—C9—C10—C11−179.4 (5)
P1—O2—C15A—C16A134.5 (4)C14—C9—C10—C11−0.4 (7)
P1—O3—C17A—C18A139.4 (7)C8—C9—C14—C13178.7 (5)
C6—C1—C2—C3−0.3 (5)C10—C9—C14—C13−0.3 (8)
C7—C1—C2—C3−179.3 (3)C9—C10—C11—C121.1 (8)
C2—C1—C6—C50.2 (5)C10—C11—C12—C13−1.1 (10)
C7—C1—C6—C5179.2 (3)C11—C12—C13—C140.4 (10)
C2—C1—C7—P172.4 (4)C12—C13—C14—C90.3 (9)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O1—H1···O4i0.86 (4)1.87 (4)2.718 (3)170 (5)
C10—H10···O4i0.932.543.409 (4)155
C16A—H16B···CgAii0.972.943.657 (8)133

Symmetry codes: (i) −x+1/2, −y+3/2, −z+1; (ii) x, −y+1, z+1/2.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: HB2959).

References

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