organic compounds
4-(4-Propoxybenzoyloxy)benzoic acid
aDepartment of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan, and bDepartment of Chemistry, Faculty of Engineering, Gifu University, Yanagido, Gifu 501-1193, Japan
*Correspondence e-mail: shameed@qau.edu.pk
The title compound, C17H16O5, is an important intermediate for the synthesis of side-chain ligands for polymeric liquid crystals. The propoxy and benzoic acid groups subtend dihedral angles of 4.36 (6) and 55.35 (6)°, respectively, with the central benzoyloxy unit. The is stabilized by an intermolecular O—H⋯O hydrogen bond.
Related literature
For related literature, see: Ahmad et al. (2003); Aranzazu et al. (2006); Cady et al. (2002); Hameed & Rama (2004); Hartung et al. (1997); Hussain et al. (2003, 2005); Kong & Tang (1998); Nazir et al. (2008a,b); Ribeiro et al. (2008); Shafiq et al. (2003, 2005); Wu & Hsu (2007); Wu & Lin (2007).
Experimental
Crystal data
|
Refinement
|
Data collection: CrystalClear (Molecular Structure Corporation & Rigaku, 2001); cell CrystalClear; data reduction: TEXSAN (Molecular Structure Corporation & Rigaku, 2004); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXL97 and TEXSAN.
Supporting information
10.1107/S1600536808016942/hg2407sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536808016942/hg2407Isup2.hkl
To a solution of 4-hydroxybenzaldehyde (0.032 moles) in 50 ml of triethylamine (TEA) was added an equivalent amount of 4-propoxybenzoylchloride with stirring and the mixture heated at 333 K for 1 hour. The excess TEA was removed in vacuo and the product, after recrystallization from hot ethanol, was subjected to KMnO4 oxidation. The 4-(4-propoxybenzoyloxy)benzaldehyde (0.025 moles) was dissolved in acetone (100 ml) and aqueous KMnO4 (0.025 moles) was added dropwise at room temperature with stirring. The stirring was continued for three hours when the reaction mixture was filtered and the filtrate acidified using 6M HCl. The product was purified by recrystallization from acetone. Yield: 93% (from 4-(4-propoxybenzoyloxy)benzaldehyde); m.p: 478-480.5K; IR (νmax, KBr, cm-1): 3100-2400, 1731, 1685, 1603, 1512, 1425, 1300, 1260, 1206, 1163, 1061, 1009, 758; 1H-NMR (300 MHz,DMSO-d6): δ 0.99 (3H, t, J = 7.2 Hz), 1.77 (2H, sex, J = 6.9 Hz), 4.05 (2H, t, J = 6.6 Hz),7.12 (2H, d, J = 8.7 Hz), 7.4 (2H, d, J = 8.7 Hz), 8.03 (2H, d, J = 8.7 Hz),8.08 (2H, d, J = 8.7 Hz), 13.02 (1H, bs); 13C-NMR (75 MHz, DMSO-d6): 10.75, 22.33, 69.91, 115.16, 120.85, 122.70, 128.79, 131.35, 132.60, 154.65, 163.82, 164.29, 167.12.
The O-bound H atom was refined isotropically. All the other H atoms were placed in idealized positions and treated as riding atoms, with C—H distance in the range 0.95–0.99 Å and Uiso(H) = 1.2Ueq(C) or 1.5Ueq(C).
Data collection: CrystalClear (Molecular Structure Corporation & Rigaku, 2001); cell
CrystalClear (Molecular Structure Corporation & Rigaku, 2001); data reduction: TEXSAN (Molecular Structure Corporation & Rigaku, 2004); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and TEXSAN (Molecular Structure Corporation & Rigaku, 2004).Fig. 1. Molecular structure of (I) showing atom-labelling scheme and displacement ellipsoids at the 30% probability level. | |
Fig. 2. Showing hydrogen bonded molecules through N—H···O. |
C17H16O5 | F(000) = 1264 |
Mr = 300.30 | Dx = 1.379 Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71070 Å |
Hall symbol: -C 2yc | Cell parameters from 3169 reflections |
a = 21.063 (15) Å | θ = 3.4–27.5° |
b = 5.703 (4) Å | µ = 0.10 mm−1 |
c = 24.437 (18) Å | T = 123 K |
β = 99.790 (9)° | Rod, colorless |
V = 2893 (3) Å3 | 0.30 × 0.19 × 0.15 mm |
Z = 8 |
Rigaku/MSC Mercury CCD diffractometer | 3297 independent reflections |
Radiation source: fine-focus sealed tube | 2824 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.051 |
ω scans | θmax = 27.5°, θmin = 3.4° |
Absorption correction: empirical (using intensity measurements) (NUMABS; Higashi, 1999) | h = −23→27 |
Tmin = 0.970, Tmax = 0.985 | k = −7→5 |
11426 measured reflections | l = −31→31 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.084 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.146 | H-atom parameters constrained |
S = 1.26 | w = 1/[σ2(Fo2) + (0.026P)2 + 6.5341P] where P = (Fo2 + 2Fc2)/3 |
3297 reflections | (Δ/σ)max < 0.001 |
201 parameters | Δρmax = 0.29 e Å−3 |
0 restraints | Δρmin = −0.28 e Å−3 |
C17H16O5 | V = 2893 (3) Å3 |
Mr = 300.30 | Z = 8 |
Monoclinic, C2/c | Mo Kα radiation |
a = 21.063 (15) Å | µ = 0.10 mm−1 |
b = 5.703 (4) Å | T = 123 K |
c = 24.437 (18) Å | 0.30 × 0.19 × 0.15 mm |
β = 99.790 (9)° |
Rigaku/MSC Mercury CCD diffractometer | 3297 independent reflections |
Absorption correction: empirical (using intensity measurements) (NUMABS; Higashi, 1999) | 2824 reflections with I > 2σ(I) |
Tmin = 0.970, Tmax = 0.985 | Rint = 0.051 |
11426 measured reflections |
R[F2 > 2σ(F2)] = 0.084 | 0 restraints |
wR(F2) = 0.146 | H-atom parameters constrained |
S = 1.26 | Δρmax = 0.29 e Å−3 |
3297 reflections | Δρmin = −0.28 e Å−3 |
201 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
C1 | 0.12026 (11) | 0.2626 (4) | 0.39828 (9) | 0.0171 (5) | |
C2 | 0.15716 (12) | 0.4515 (4) | 0.42065 (10) | 0.0223 (5) | |
H2 | 0.1686 | 0.5699 | 0.3968 | 0.027* | |
C3 | 0.17771 (13) | 0.4698 (4) | 0.47766 (10) | 0.0229 (5) | |
H3 | 0.2030 | 0.6000 | 0.4926 | 0.027* | |
C4 | 0.16099 (12) | 0.2958 (4) | 0.51274 (10) | 0.0198 (5) | |
C5 | 0.12360 (12) | 0.1058 (4) | 0.49037 (10) | 0.0229 (5) | |
H5 | 0.1120 | −0.0124 | 0.5142 | 0.027* | |
C6 | 0.10351 (12) | 0.0891 (4) | 0.43378 (10) | 0.0212 (5) | |
H6 | 0.0781 | −0.0408 | 0.4188 | 0.025* | |
C7 | 0.09682 (11) | 0.2342 (4) | 0.33803 (10) | 0.0176 (5) | |
O1 | 0.06221 (9) | 0.0793 (3) | 0.31697 (7) | 0.0250 (4) | |
O2 | 0.11946 (8) | 0.4078 (3) | 0.30793 (7) | 0.0216 (4) | |
C8 | 0.09736 (11) | 0.4149 (4) | 0.25035 (9) | 0.0181 (5) | |
C9 | 0.06788 (11) | 0.6204 (4) | 0.22986 (10) | 0.0192 (5) | |
H9 | 0.0624 | 0.7460 | 0.2542 | 0.023* | |
C10 | 0.04640 (11) | 0.6402 (4) | 0.17308 (10) | 0.0177 (5) | |
H10 | 0.0254 | 0.7794 | 0.1583 | 0.021* | |
C11 | 0.05562 (11) | 0.4570 (4) | 0.13782 (10) | 0.0169 (5) | |
C12 | 0.08634 (11) | 0.2523 (4) | 0.15939 (10) | 0.0188 (5) | |
H12 | 0.0928 | 0.1274 | 0.1352 | 0.023* | |
C13 | 0.10753 (12) | 0.2303 (4) | 0.21606 (10) | 0.0202 (5) | |
H13 | 0.1286 | 0.0915 | 0.2310 | 0.024* | |
C14 | 0.03310 (11) | 0.4762 (4) | 0.07712 (10) | 0.0177 (5) | |
O3 | 0.00181 (9) | 0.6673 (3) | 0.06089 (7) | 0.0272 (4) | |
H3O | −0.0102 | 0.6630 | 0.0263 | 0.041* | |
O4 | 0.04427 (9) | 0.3198 (3) | 0.04501 (7) | 0.0244 (4) | |
O5 | 0.17781 (9) | 0.2955 (3) | 0.56890 (7) | 0.0238 (4) | |
C15 | 0.21608 (12) | 0.4869 (4) | 0.59482 (10) | 0.0202 (5) | |
H15A | 0.1923 | 0.6365 | 0.5875 | 0.024* | |
H15B | 0.2568 | 0.4988 | 0.5799 | 0.024* | |
C16 | 0.22997 (12) | 0.4371 (4) | 0.65666 (10) | 0.0207 (5) | |
H16A | 0.2560 | 0.2922 | 0.6636 | 0.025* | |
H16B | 0.1889 | 0.4117 | 0.6704 | 0.025* | |
C17 | 0.26641 (13) | 0.6408 (5) | 0.68816 (11) | 0.0277 (6) | |
H17A | 0.3098 | 0.6505 | 0.6788 | 0.042* | |
H17B | 0.2696 | 0.6153 | 0.7282 | 0.042* | |
H17C | 0.2433 | 0.7875 | 0.6777 | 0.042* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0169 (12) | 0.0177 (11) | 0.0174 (12) | 0.0001 (9) | 0.0053 (9) | −0.0012 (9) |
C2 | 0.0269 (13) | 0.0199 (12) | 0.0207 (13) | −0.0054 (10) | 0.0062 (10) | 0.0038 (10) |
C3 | 0.0262 (13) | 0.0212 (12) | 0.0214 (13) | −0.0056 (10) | 0.0042 (10) | 0.0002 (10) |
C4 | 0.0189 (12) | 0.0255 (13) | 0.0156 (12) | 0.0005 (10) | 0.0044 (10) | 0.0003 (10) |
C5 | 0.0275 (14) | 0.0237 (12) | 0.0184 (13) | −0.0057 (10) | 0.0061 (10) | 0.0025 (10) |
C6 | 0.0220 (13) | 0.0210 (12) | 0.0213 (13) | −0.0045 (10) | 0.0051 (10) | −0.0004 (10) |
C7 | 0.0181 (12) | 0.0163 (11) | 0.0192 (12) | 0.0005 (9) | 0.0058 (10) | 0.0002 (9) |
O1 | 0.0298 (10) | 0.0258 (9) | 0.0203 (9) | −0.0100 (8) | 0.0067 (8) | −0.0043 (7) |
O2 | 0.0274 (10) | 0.0236 (9) | 0.0134 (8) | −0.0069 (7) | 0.0024 (7) | 0.0006 (7) |
C8 | 0.0174 (12) | 0.0232 (12) | 0.0138 (12) | −0.0057 (9) | 0.0031 (9) | 0.0022 (9) |
C9 | 0.0193 (12) | 0.0188 (11) | 0.0203 (12) | −0.0009 (9) | 0.0063 (10) | −0.0032 (9) |
C10 | 0.0175 (12) | 0.0176 (11) | 0.0184 (12) | 0.0006 (9) | 0.0045 (9) | 0.0013 (9) |
C11 | 0.0136 (11) | 0.0193 (11) | 0.0181 (12) | −0.0008 (9) | 0.0040 (9) | 0.0014 (9) |
C12 | 0.0204 (12) | 0.0173 (11) | 0.0198 (12) | −0.0009 (9) | 0.0072 (10) | −0.0012 (9) |
C13 | 0.0208 (12) | 0.0199 (12) | 0.0200 (12) | −0.0007 (9) | 0.0036 (10) | 0.0021 (9) |
C14 | 0.0153 (11) | 0.0190 (11) | 0.0196 (12) | 0.0013 (9) | 0.0055 (9) | −0.0009 (9) |
O3 | 0.0382 (11) | 0.0267 (10) | 0.0155 (9) | 0.0145 (8) | 0.0012 (8) | 0.0001 (7) |
O4 | 0.0296 (10) | 0.0244 (9) | 0.0193 (9) | 0.0073 (8) | 0.0043 (7) | −0.0031 (7) |
O5 | 0.0281 (10) | 0.0259 (9) | 0.0168 (9) | −0.0071 (8) | 0.0024 (7) | 0.0004 (7) |
C15 | 0.0200 (12) | 0.0220 (12) | 0.0184 (12) | −0.0036 (10) | 0.0029 (10) | −0.0007 (10) |
C16 | 0.0181 (12) | 0.0269 (13) | 0.0174 (12) | 0.0002 (10) | 0.0035 (10) | 0.0009 (10) |
C17 | 0.0284 (14) | 0.0338 (15) | 0.0200 (13) | −0.0014 (11) | 0.0012 (11) | 0.0000 (11) |
C1—C2 | 1.385 (3) | C10—H10 | 0.9500 |
C1—C6 | 1.400 (3) | C11—C12 | 1.394 (3) |
C1—C7 | 1.480 (3) | C11—C14 | 1.482 (3) |
C2—C3 | 1.391 (4) | C12—C13 | 1.387 (3) |
C2—H2 | 0.9500 | C12—H12 | 0.9500 |
C3—C4 | 1.395 (3) | C13—H13 | 0.9500 |
C3—H3 | 0.9500 | C14—O4 | 1.237 (3) |
C4—O5 | 1.358 (3) | C14—O3 | 1.300 (3) |
C4—C5 | 1.395 (3) | O3—H3O | 0.8400 |
C5—C6 | 1.379 (3) | O5—C15 | 1.438 (3) |
C5—H5 | 0.9500 | C15—C16 | 1.516 (3) |
C6—H6 | 0.9500 | C15—H15A | 0.9900 |
C7—O1 | 1.204 (3) | C15—H15B | 0.9900 |
C7—O2 | 1.367 (3) | C16—C17 | 1.527 (4) |
O2—C8 | 1.406 (3) | C16—H16A | 0.9900 |
C8—C9 | 1.380 (3) | C16—H16B | 0.9900 |
C8—C13 | 1.385 (3) | C17—H17A | 0.9800 |
C9—C10 | 1.389 (3) | C17—H17B | 0.9800 |
C9—H9 | 0.9500 | C17—H17C | 0.9800 |
C10—C11 | 1.389 (3) | ||
C2—C1—C6 | 119.3 (2) | C10—C11—C14 | 120.7 (2) |
C2—C1—C7 | 123.2 (2) | C12—C11—C14 | 119.3 (2) |
C6—C1—C7 | 117.6 (2) | C13—C12—C11 | 120.2 (2) |
C1—C2—C3 | 120.8 (2) | C13—C12—H12 | 119.9 |
C1—C2—H2 | 119.6 | C11—C12—H12 | 119.9 |
C3—C2—H2 | 119.6 | C8—C13—C12 | 118.6 (2) |
C2—C3—C4 | 119.6 (2) | C8—C13—H13 | 120.7 |
C2—C3—H3 | 120.2 | C12—C13—H13 | 120.7 |
C4—C3—H3 | 120.2 | O4—C14—O3 | 123.5 (2) |
O5—C4—C3 | 124.9 (2) | O4—C14—C11 | 121.2 (2) |
O5—C4—C5 | 115.3 (2) | O3—C14—C11 | 115.3 (2) |
C3—C4—C5 | 119.7 (2) | C14—O3—H3O | 109.5 |
C6—C5—C4 | 120.2 (2) | C4—O5—C15 | 118.32 (19) |
C6—C5—H5 | 119.9 | O5—C15—C16 | 107.18 (19) |
C4—C5—H5 | 119.9 | O5—C15—H15A | 110.3 |
C5—C6—C1 | 120.4 (2) | C16—C15—H15A | 110.3 |
C5—C6—H6 | 119.8 | O5—C15—H15B | 110.3 |
C1—C6—H6 | 119.8 | C16—C15—H15B | 110.3 |
O1—C7—O2 | 122.9 (2) | H15A—C15—H15B | 108.5 |
O1—C7—C1 | 125.5 (2) | C15—C16—C17 | 110.8 (2) |
O2—C7—C1 | 111.61 (19) | C15—C16—H16A | 109.5 |
C7—O2—C8 | 118.23 (18) | C17—C16—H16A | 109.5 |
C9—C8—C13 | 122.2 (2) | C15—C16—H16B | 109.5 |
C9—C8—O2 | 116.1 (2) | C17—C16—H16B | 109.5 |
C13—C8—O2 | 121.7 (2) | H16A—C16—H16B | 108.1 |
C8—C9—C10 | 118.8 (2) | C16—C17—H17A | 109.5 |
C8—C9—H9 | 120.6 | C16—C17—H17B | 109.5 |
C10—C9—H9 | 120.6 | H17A—C17—H17B | 109.5 |
C11—C10—C9 | 120.2 (2) | C16—C17—H17C | 109.5 |
C11—C10—H10 | 119.9 | H17A—C17—H17C | 109.5 |
C9—C10—H10 | 119.9 | H17B—C17—H17C | 109.5 |
C10—C11—C12 | 120.0 (2) | ||
C6—C1—C2—C3 | 0.2 (4) | C13—C8—C9—C10 | 1.5 (4) |
C7—C1—C2—C3 | 179.7 (2) | O2—C8—C9—C10 | 178.5 (2) |
C1—C2—C3—C4 | 0.0 (4) | C8—C9—C10—C11 | −1.1 (3) |
C2—C3—C4—O5 | −179.5 (2) | C9—C10—C11—C12 | 0.2 (3) |
C2—C3—C4—C5 | −0.3 (4) | C9—C10—C11—C14 | −179.8 (2) |
O5—C4—C5—C6 | 179.7 (2) | C10—C11—C12—C13 | 0.3 (3) |
C3—C4—C5—C6 | 0.3 (4) | C14—C11—C12—C13 | −179.7 (2) |
C4—C5—C6—C1 | −0.1 (4) | C9—C8—C13—C12 | −1.1 (4) |
C2—C1—C6—C5 | −0.1 (4) | O2—C8—C13—C12 | −177.8 (2) |
C7—C1—C6—C5 | −179.7 (2) | C11—C12—C13—C8 | 0.2 (4) |
C2—C1—C7—O1 | −176.3 (2) | C10—C11—C14—O4 | 175.9 (2) |
C6—C1—C7—O1 | 3.3 (4) | C12—C11—C14—O4 | −4.1 (3) |
C2—C1—C7—O2 | 3.8 (3) | C10—C11—C14—O3 | −3.7 (3) |
C6—C1—C7—O2 | −176.6 (2) | C12—C11—C14—O3 | 176.3 (2) |
O1—C7—O2—C8 | 4.9 (3) | C3—C4—O5—C15 | −0.4 (4) |
C1—C7—O2—C8 | −175.2 (2) | C5—C4—O5—C15 | −179.7 (2) |
C7—O2—C8—C9 | 122.6 (2) | C4—O5—C15—C16 | −177.7 (2) |
C7—O2—C8—C13 | −60.5 (3) | O5—C15—C16—C17 | −175.9 (2) |
D—H···A | D—H | H···A | D···A | D—H···A |
O3—H3O···O4i | 0.84 | 1.77 | 2.606 (3) | 172 |
Symmetry code: (i) −x, −y+1, −z. |
Experimental details
Crystal data | |
Chemical formula | C17H16O5 |
Mr | 300.30 |
Crystal system, space group | Monoclinic, C2/c |
Temperature (K) | 123 |
a, b, c (Å) | 21.063 (15), 5.703 (4), 24.437 (18) |
β (°) | 99.790 (9) |
V (Å3) | 2893 (3) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 0.10 |
Crystal size (mm) | 0.30 × 0.19 × 0.15 |
Data collection | |
Diffractometer | Rigaku/MSC Mercury CCD diffractometer |
Absorption correction | Empirical (using intensity measurements) (NUMABS; Higashi, 1999) |
Tmin, Tmax | 0.970, 0.985 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 11426, 3297, 2824 |
Rint | 0.051 |
(sin θ/λ)max (Å−1) | 0.649 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.084, 0.146, 1.26 |
No. of reflections | 3297 |
No. of parameters | 201 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.29, −0.28 |
Computer programs: CrystalClear (Molecular Structure Corporation & Rigaku, 2001), SIR97 (Altomare et al., 1999), ORTEPII (Johnson, 1976), SHELXL97 (Sheldrick, 2008) and TEXSAN (Molecular Structure Corporation & Rigaku, 2004).
D—H···A | D—H | H···A | D···A | D—H···A |
O3—H3O···O4i | 0.84 | 1.77 | 2.606 (3) | 172.1 |
Symmetry code: (i) −x, −y+1, −z. |
Acknowledgements
MKR is grateful to The Higher Education Commission of Pakistan for financial support under the International Support initiative program for Doctoral Fellowships in Gifu University, Japan.
References
Ahmad, H. B., Rama, N. H., Hussain, M., Hussain, M. T., Qasim, M. M., Hameed, S., Malana, M. A. & Malik, A. (2003). Indian J. Chem. 42B, 611-615. CAS Google Scholar
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. Web of Science CrossRef CAS IUCr Journals Google Scholar
Aranzazu, M.-G., Ernesto, P. & Antonio, B. (2006). Polymer, 47, 2080–2090. Google Scholar
Cady, A., Olson, D. A., Han, X. F., Nguyen, H. T. & Huang, C. C. (2002). Rapid Commun. Phys. Rev. E. 65, 030701. CrossRef Google Scholar
Hameed, S. & Rama, N. H. (2004). J. Chem. Soc. Pak. 26, 157–162. CAS Google Scholar
Hartung, H., Hoffmann, F. & Weissflog, W. (1997). J. Mol. Struct. 415, 205–214. CSD CrossRef CAS Web of Science Google Scholar
Higashi, T. (1999). NUMABS. Rigaku Corporation, Tokyo, Japan. Google Scholar
Hussain, M., Hussain, M. T., Rama, N. H., Hameed, S., Malik, A. & Khan, K. M. (2003). Nat. Prod. Res. 17, 207–214. Web of Science CrossRef PubMed CAS Google Scholar
Hussain, M. T., Rama, N. H., Hameed, S., Malik, A. & Khan, K. M. (2005). Nat. Prod. Res. 19, 41–51. Web of Science CrossRef PubMed CAS Google Scholar
Johnson, C. K. (1976). ORTEPII. Report ORNL-5138. Oak Ridge National Laboratory, Tenessee, USA. Google Scholar
Kong, X. X. & Tang, B. Z. (1998). Chem. Mater. 10, 3352–3363. Web of Science CrossRef CAS Google Scholar
Molecular Structure Corporation & Rigaku (2001). Crystal Clear. MSC, The Woodlands, Texas, USA, and Rigaku Corporation, Tokyo, Japan. Google Scholar
Molecular Structure Corporation & Rigaku (2004). TEXSAN. MSC, The Woodlands, Texas, USA, and Rigaku Corporation, Tokyo, Japan. Google Scholar
Nazir, S., Muhammad, K., Khawar Rauf, M., Ebihara, M. & Hameed, S. (2008a). Acta Cryst. E64, o1013. Web of Science CSD CrossRef IUCr Journals Google Scholar
Nazir, S., Khawar Rauf, M., Ebihara, M. & Hameed, S. (2008b). Acta Cryst. E64, o423. Web of Science CSD CrossRef IUCr Journals Google Scholar
Ribeiro, G., Benadiba, M., Colquhoun, A. & Silva, D. D. (2008). Polyhedron, 27, 1131–1137. Web of Science CrossRef CAS Google Scholar
Shafiq, Z., Arfan, M., Rama, N. H., Hameed, S., Abbas, G. & Hussain, M. T. (2005). Turk. J. Chem. 29, 321–325. CAS Google Scholar
Shafiq, Z., Arfan, M., Rama, N. H., Hussain, M. & Hameed, S. (2003). Indian J. Chem. 42B, 1523–1526. CAS Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Wu, S.-L. & Hsu, H.-N. (2007). Liq. Cryst. 34, 1159–1165. Web of Science CrossRef CAS Google Scholar
Wu, S.-L. & Lin, C.-Y. (2007). Liq. Cryst. 34, 25–31. Web of Science CrossRef CAS Google Scholar
This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.
Differently substituted aromatic carboxylic acids having benzene rings either joined directly through a covalent bond (Wu & Hsu 2007) or through some functional group, mostly an ester (Cady et al., 2002; Wu & Lin 2007) or an olefin (Nazir et al., 2008a; 2008b), have been investigated for their liquid crystal properties. Such acids have been used in the synthesis of intermediates for side-chain liquid crystal polymers (Kong & Tang 1998) as well as for main-chain liquid crystal polymers (Aranzazu et al., 2006). In addition, the carboxylic acids, in general, have been used as intermediates in the synthesis of a large number of organic compounds (Hussain et al., 2005; 2003; Shafiq et al., 2005; 2003; Ahmad et al., 2003). The pharmaceutical industry has also benefited from this class of compounds (Ribeiro et al., 2008; Hameed & Rama, 2004). The title compound (I) was synthesized in our lab as an intermediate in the synthesis of side-chain liquid crystal polymers, by treating 4-hydroxybenzaldehyde with 4-propyloxybenzoylchloride followed by KMnO4 oxidation. In this report, the crystal structure of (I) is presented. Bond lengths and angles are within the normal ranges as given for benzoyloxybenzoic acids (Hartung et al., 1997). The C(14)—O(4), C(14)—O(3),C(7)—O(1) and C(7)—O(2) bond lengths are 1.237 (3), 1.300 (3), 1.204 (3) and 1.367 (3) respectively, clearly indicating the partial double bond character of the carboxylate groups. The benzoic acid groups subtend dihedral angles [55.35 (6)°] with the central benzoyloxy moiety C(1)/C(2)/C(3)/C(4)/C(5)/C(6)/C(7)/O(1)/O(2). Two molecules related by an inversion center form a dimer via two hydrogen bonds composed of two carboxyl groups as shown in Fig. 2.