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

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ISSN: 2056-9890

2-(4-Chloro­phen­yl)-2-oxo­ethyl 2-meth­­oxy­benzoate

aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, bOrganic Electronics Division, Department of Chemistry, National Institute of Technology–Karnataka, Surathkal, Mangalore 575 025, India, and cDepartment of Physics, National Institute of Technology–Karnataka, Surathkal, Mangalore 575 025, India
*Correspondence e-mail: hkfun@usm.my

(Received 1 June 2011; accepted 2 June 2011; online 18 June 2011)

In the title compound, C16H13ClO4, the two benzene rings make a dihedral angle of 86.38 (8)°. In the crystal, inter­molecular C—H⋯O hydrogen bonds link the mol­ecules to form columns along the a axis. The mol­ecules are also stabilized by a ππ stacking inter­action, with a centroid–centroid distance of 3.7793 (10) Å between the inversion-related benzene rings.

Related literature

For general background to phenacyl benzoates, see: Rather & Reid (1919[Rather, J. B. & Reid, E. (1919). J. Am. Chem. Soc. 41, 75-83.]); Sheehan & Umezaw (1973[Sheehan, J. C. & Umezaw, K. (1973). J. Org. Chem. 58, 3771-3773.]); Ruzicka et al. (2002[Ruzicka, R., Zabadal, M. & Klan, P. (2002). Synth. Commun. 32, 2581-2590.]); Litera et al. (2006[Litera, J. K., Loya, A. D. & Klan, P. (2006). J. Org. Chem. 71, 713-723.]). For applications and synthesis of oxazoles, imidazoles and benzoxazepines, see: Huang et al. (1996[Huang, W., Pian, J., Chen, B., Pei, W. & Ye, X. (1996). Tetrahedron, 52, 10131-10136.]); Gandhi et al. (1995[Gandhi, S. S., Bell, K. L. & Gibson, M. S. (1995). Tetrahedron, 51, 13301-13308.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]).

[Scheme 1]

Experimental

Crystal data
  • C16H13ClO4

  • Mr = 304.71

  • Orthorhombic, P b c a

  • a = 7.7207 (6) Å

  • b = 14.4411 (12) Å

  • c = 26.064 (2) Å

  • V = 2906.0 (4) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.28 mm−1

  • T = 296 K

  • 0.51 × 0.29 × 0.19 mm

Data collection
  • Bruker APEXII DUO CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.829, Tmax = 0.950

  • 16215 measured reflections

  • 4027 independent reflections

  • 2731 reflections with I > 2σ(I)

  • Rint = 0.025

Refinement
  • R[F2 > 2σ(F2)] = 0.041

  • wR(F2) = 0.116

  • S = 1.02

  • 4027 reflections

  • 190 parameters

  • H-atom parameters constrained

  • Δρmax = 0.17 e Å−3

  • Δρmin = −0.35 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C2—H2A⋯O1i 0.93 2.40 3.301 (2) 164
Symmetry code: (i) x+1, y, z.

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Phenacyl benzoate derivatives are very important in identification of organic acids (Rather & Reid, 1919) as they undergo photolysis in neutral and mild conditions (Sheehan & Umezaw, 1973; Ruzicka et al., 2002 ; Litera et al., 2006). They find applications in the field of synthetic chemistry for the synthesis of oxazoles, imidazoles (Huang et al., 1996) and benzoxazepines (Gandhi et al., 1995). The phenacyl esters are usually prepared by reaction between acids with phenacylbromide derivatives in DMF using sodium or potassium carbonate as base. We hereby report the crystal structure of 2-(4-chlorophenyl)-2-oxoethyl 2-methoxybenzoate, (I), which has potential commercial importance.

In the title compound of (I), the bond lengths (Allen et al., 1987) and angles show the normal values. The two benzene rings (C1–C6 and C10–C15) make a dihedral angle of 86.38 (8)°.

In the crystal packing (Fig. 2), intermolecular C2—H2A···O1 hydrogen bonds (Table 1) link the molecules to form columns down to the a-axis. The molecules are also stabilized by ππ stacking interactions between the inversion-related benzene rings (C1–C6 ; centroid Cg1) with a Cg1···Cg1ii separation of 3.7793 (10) Å [symmetry code: (ii) 2 - x, -y, 2 - z].

Related literature top

For general background to phenacyl benzoates, see: Rather & Reid (1919); Sheehan & Umezaw (1973) ; Ruzicka et al. (2002) ; Litera et al. (2006). For applications and synthesis of oxazoles, imidazoles and benzoxazepines, see: Huang et al. (1996); Gandhi et al. (1995). For bond-length data, see: Allen et al. (1987).

Experimental top

The mixture of 2-methoxybenzoic acid (1.0 g, 0.0065 mol), potassium carbonate (0.98 g, 0.0071 mol) and 2-bromo-1-(4-chlorophenyl)ethanone (1.45 g, 0.0065 mol) in dimethylformamide (10 ml) was stirred at room temperature for 2 h. On cooling, colorless needle-shaped crystals of 2-(4-chlorophenyl)-2-oxoethyl 2-methoxybenzoate begins to separate out. It was collected by filtration and recrystallized from ethanol. Yield : 1.9 g, 95 %, M.p. : 391–392 K, (CAS Registry Number: 282714–31–2).

Refinement top

All H atoms were placed in calculated positions with C–H = 0.93–0.97 Å. The Uiso(H) values were constrained to be 1.5Ueq of the carrier atom for methyl H atoms and 1.2Ueq for the remaining H atoms.

Computing details top

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

Figures top
[Figure 1] Fig. 1. The structure of the title compound, showing 50% probability displacement ellipsoids and the atom-numbering scheme.
[Figure 2] Fig. 2. The crystal packing, viewed along the c axis, showing columns down to the a axis. Hydrogen atoms that are not involved in hydrogen bonding (dashed lines) are omitted for clarity.
2-(4-Chlorophenyl)-2-oxoethyl 2-methoxybenzoate top
Crystal data top
C16H13ClO4F(000) = 1264
Mr = 304.71Dx = 1.393 Mg m3
Orthorhombic, PbcaMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2abCell parameters from 3855 reflections
a = 7.7207 (6) Åθ = 2.9–29.2°
b = 14.4411 (12) ŵ = 0.28 mm1
c = 26.064 (2) ÅT = 296 K
V = 2906.0 (4) Å3Block, colourless
Z = 80.51 × 0.29 × 0.19 mm
Data collection top
Bruker APEXII DUO CCD area-detector
diffractometer
4027 independent reflections
Radiation source: fine-focus sealed tube2731 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.025
ϕ and ω scansθmax = 29.5°, θmin = 2.9°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
h = 109
Tmin = 0.829, Tmax = 0.950k = 1420
16215 measured reflectionsl = 3635
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)] = 0.041Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.116H-atom parameters constrained
S = 1.02 w = 1/[σ2(Fo2) + (0.0471P)2 + 0.6504P]
where P = (Fo2 + 2Fc2)/3
4027 reflections(Δ/σ)max = 0.001
190 parametersΔρmax = 0.17 e Å3
0 restraintsΔρmin = 0.35 e Å3
Crystal data top
C16H13ClO4V = 2906.0 (4) Å3
Mr = 304.71Z = 8
Orthorhombic, PbcaMo Kα radiation
a = 7.7207 (6) ŵ = 0.28 mm1
b = 14.4411 (12) ÅT = 296 K
c = 26.064 (2) Å0.51 × 0.29 × 0.19 mm
Data collection top
Bruker APEXII DUO CCD area-detector
diffractometer
4027 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
2731 reflections with I > 2σ(I)
Tmin = 0.829, Tmax = 0.950Rint = 0.025
16215 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0410 restraints
wR(F2) = 0.116H-atom parameters constrained
S = 1.02Δρmax = 0.17 e Å3
4027 reflectionsΔρmin = 0.35 e Å3
190 parameters
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
Cl11.18791 (7)0.06652 (3)1.10182 (2)0.08142 (19)
O10.45975 (15)0.12921 (11)0.96747 (5)0.0746 (4)
O20.49777 (16)0.19520 (7)0.87365 (5)0.0624 (3)
O30.46624 (16)0.04491 (8)0.85569 (5)0.0667 (3)
O40.19233 (15)0.00492 (7)0.79740 (4)0.0600 (3)
C10.9263 (2)0.14336 (11)0.97782 (6)0.0523 (4)
H1A0.95150.16780.94570.063*
C21.0596 (2)0.12582 (11)1.01201 (7)0.0571 (4)
H2A1.17390.13821.00310.068*
C31.0198 (2)0.08973 (10)1.05937 (6)0.0546 (4)
C40.8517 (2)0.07047 (11)1.07348 (7)0.0582 (4)
H4A0.82760.04591.10570.070*
C50.7198 (2)0.08809 (11)1.03928 (6)0.0534 (4)
H5A0.60590.07531.04850.064*
C60.75479 (19)0.12480 (10)0.99111 (6)0.0455 (3)
C70.6086 (2)0.14152 (10)0.95508 (6)0.0504 (4)
C80.6513 (2)0.17422 (11)0.90174 (6)0.0543 (4)
H8A0.72360.22900.90370.065*
H8B0.71590.12650.88390.065*
C90.4084 (2)0.12187 (10)0.85521 (5)0.0487 (3)
C100.2379 (2)0.15154 (10)0.83489 (5)0.0462 (3)
C110.1787 (2)0.24124 (11)0.84420 (6)0.0566 (4)
H11A0.24690.28130.86350.068*
C120.0216 (3)0.27210 (13)0.82551 (7)0.0672 (5)
H12A0.01560.33220.83210.081*
C130.0790 (2)0.21275 (13)0.79706 (7)0.0669 (5)
H13A0.18470.23310.78420.080*
C140.0255 (2)0.12352 (12)0.78741 (6)0.0594 (4)
H14A0.09540.08420.76820.071*
C150.1320 (2)0.09184 (10)0.80609 (5)0.0475 (3)
C160.0868 (3)0.05690 (13)0.76827 (8)0.0822 (6)
H16A0.14450.11550.76500.123*
H16B0.06690.03130.73480.123*
H16C0.02210.06550.78540.123*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0864 (4)0.0640 (3)0.0939 (4)0.0087 (2)0.0384 (3)0.0086 (2)
O10.0402 (6)0.1070 (11)0.0766 (8)0.0079 (7)0.0051 (6)0.0064 (7)
O20.0648 (7)0.0453 (6)0.0772 (8)0.0033 (5)0.0195 (6)0.0001 (5)
O30.0694 (8)0.0505 (6)0.0802 (8)0.0105 (6)0.0215 (6)0.0133 (5)
O40.0707 (8)0.0479 (6)0.0615 (6)0.0005 (5)0.0169 (5)0.0098 (5)
C10.0459 (8)0.0574 (8)0.0537 (8)0.0062 (7)0.0056 (7)0.0057 (7)
C20.0407 (8)0.0584 (9)0.0721 (10)0.0042 (7)0.0000 (7)0.0136 (8)
C30.0601 (10)0.0413 (7)0.0623 (9)0.0040 (7)0.0108 (8)0.0124 (6)
C40.0712 (11)0.0506 (8)0.0529 (9)0.0036 (8)0.0003 (8)0.0043 (7)
C50.0501 (9)0.0535 (8)0.0566 (9)0.0060 (7)0.0095 (7)0.0071 (7)
C60.0412 (7)0.0440 (7)0.0513 (8)0.0034 (6)0.0038 (6)0.0112 (6)
C70.0443 (8)0.0480 (7)0.0590 (9)0.0049 (7)0.0024 (7)0.0121 (6)
C80.0497 (9)0.0506 (8)0.0626 (9)0.0059 (7)0.0071 (7)0.0005 (7)
C90.0575 (9)0.0461 (8)0.0426 (7)0.0003 (7)0.0033 (6)0.0024 (6)
C100.0542 (8)0.0453 (7)0.0390 (7)0.0017 (6)0.0006 (6)0.0012 (6)
C110.0667 (10)0.0495 (8)0.0535 (8)0.0043 (8)0.0017 (7)0.0030 (7)
C120.0761 (12)0.0580 (10)0.0674 (10)0.0192 (9)0.0019 (9)0.0036 (8)
C130.0600 (10)0.0755 (11)0.0653 (10)0.0117 (9)0.0070 (9)0.0138 (9)
C140.0608 (10)0.0640 (10)0.0532 (9)0.0026 (8)0.0110 (7)0.0066 (7)
C150.0560 (9)0.0487 (7)0.0377 (7)0.0005 (7)0.0012 (6)0.0033 (6)
C160.1015 (16)0.0592 (10)0.0859 (13)0.0046 (11)0.0344 (12)0.0164 (9)
Geometric parameters (Å, º) top
Cl1—C31.7380 (17)C7—C81.505 (2)
O1—C71.2069 (19)C8—H8A0.9700
O2—C91.3521 (18)C8—H8B0.9700
O2—C81.426 (2)C9—C101.482 (2)
O3—C91.1978 (18)C10—C111.395 (2)
O4—C151.3579 (18)C10—C151.406 (2)
O4—C161.428 (2)C11—C121.381 (2)
C1—C21.384 (2)C11—H11A0.9300
C1—C61.395 (2)C12—C131.374 (3)
C1—H1A0.9300C12—H12A0.9300
C2—C31.375 (2)C13—C141.376 (3)
C2—H2A0.9300C13—H13A0.9300
C3—C41.377 (3)C14—C151.388 (2)
C4—C51.377 (2)C14—H14A0.9300
C4—H4A0.9300C16—H16A0.9600
C5—C61.390 (2)C16—H16B0.9600
C5—H5A0.9300C16—H16C0.9600
C6—C71.488 (2)
C9—O2—C8116.12 (12)H8A—C8—H8B108.0
C15—O4—C16118.10 (13)O3—C9—O2122.20 (15)
C2—C1—C6120.70 (15)O3—C9—C10127.08 (14)
C2—C1—H1A119.6O2—C9—C10110.71 (12)
C6—C1—H1A119.6C11—C10—C15118.16 (14)
C3—C2—C1118.78 (15)C11—C10—C9119.82 (14)
C3—C2—H2A120.6C15—C10—C9122.02 (13)
C1—C2—H2A120.6C12—C11—C10121.74 (16)
C2—C3—C4121.79 (15)C12—C11—H11A119.1
C2—C3—Cl1118.55 (14)C10—C11—H11A119.1
C4—C3—Cl1119.66 (14)C13—C12—C11119.05 (16)
C3—C4—C5119.14 (16)C13—C12—H12A120.5
C3—C4—H4A120.4C11—C12—H12A120.5
C5—C4—H4A120.4C12—C13—C14120.86 (17)
C4—C5—C6120.75 (15)C12—C13—H13A119.6
C4—C5—H5A119.6C14—C13—H13A119.6
C6—C5—H5A119.6C13—C14—C15120.51 (17)
C5—C6—C1118.84 (15)C13—C14—H14A119.7
C5—C6—C7118.98 (14)C15—C14—H14A119.7
C1—C6—C7122.17 (14)O4—C15—C14123.15 (14)
O1—C7—C6121.98 (15)O4—C15—C10117.17 (14)
O1—C7—C8120.12 (15)C14—C15—C10119.67 (15)
C6—C7—C8117.90 (13)O4—C16—H16A109.5
O2—C8—C7111.06 (14)O4—C16—H16B109.5
O2—C8—H8A109.4H16A—C16—H16B109.5
C7—C8—H8A109.4O4—C16—H16C109.5
O2—C8—H8B109.4H16A—C16—H16C109.5
C7—C8—H8B109.4H16B—C16—H16C109.5
C6—C1—C2—C30.0 (2)C8—O2—C9—C10170.17 (13)
C1—C2—C3—C40.2 (2)O3—C9—C10—C11170.24 (16)
C1—C2—C3—Cl1179.21 (12)O2—C9—C10—C1110.50 (19)
C2—C3—C4—C50.2 (2)O3—C9—C10—C159.9 (2)
Cl1—C3—C4—C5179.21 (12)O2—C9—C10—C15169.40 (13)
C3—C4—C5—C60.0 (2)C15—C10—C11—C120.7 (2)
C4—C5—C6—C10.2 (2)C9—C10—C11—C12179.24 (15)
C4—C5—C6—C7179.14 (14)C10—C11—C12—C130.1 (3)
C2—C1—C6—C50.2 (2)C11—C12—C13—C140.4 (3)
C2—C1—C6—C7179.12 (14)C12—C13—C14—C150.3 (3)
C5—C6—C7—O14.4 (2)C16—O4—C15—C141.0 (2)
C1—C6—C7—O1176.70 (15)C16—O4—C15—C10179.95 (16)
C5—C6—C7—C8175.29 (13)C13—C14—C15—O4179.34 (15)
C1—C6—C7—C83.6 (2)C13—C14—C15—C100.3 (2)
C9—O2—C8—C777.10 (17)C11—C10—C15—O4179.86 (13)
O1—C7—C8—O25.8 (2)C9—C10—C15—O40.0 (2)
C6—C7—C8—O2174.59 (12)C11—C10—C15—C140.7 (2)
C8—O2—C9—O310.5 (2)C9—C10—C15—C14179.15 (14)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C2—H2A···O1i0.932.403.301 (2)164
Symmetry code: (i) x+1, y, z.

Experimental details

Crystal data
Chemical formulaC16H13ClO4
Mr304.71
Crystal system, space groupOrthorhombic, Pbca
Temperature (K)296
a, b, c (Å)7.7207 (6), 14.4411 (12), 26.064 (2)
V3)2906.0 (4)
Z8
Radiation typeMo Kα
µ (mm1)0.28
Crystal size (mm)0.51 × 0.29 × 0.19
Data collection
DiffractometerBruker APEXII DUO CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2009)
Tmin, Tmax0.829, 0.950
No. of measured, independent and
observed [I > 2σ(I)] reflections
16215, 4027, 2731
Rint0.025
(sin θ/λ)max1)0.693
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.041, 0.116, 1.02
No. of reflections4027
No. of parameters190
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.17, 0.35

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C2—H2A···O1i0.93002.40003.301 (2)164.00
Symmetry code: (i) x+1, y, z.
 

Footnotes

Thomson Reuters ResearcherID: A-3561-2009.

Acknowledgements

HKF and SIJA thank Universiti Sains Malaysia for the Research University Grants (Nos. 1001/PFIZIK/811160 and 1001/PFIZIK/811151). AMI is grateful to the Department of Atomic Energy, Board for Research in Nuclear Sciences, Government of India for the Young Scientist award. BG thanks the Department of Information Technology, New Delhi, India for financial support.

References

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Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
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