5-Methyl-3-phenyl­isoxazole-4-carb­oxy­lic acid

Chandra; Srikantamurthy, N.; Vishalakshi, G.J.; Jeyaseelan, S.; Umesha, K.B.; Mahendra, M.

doi:10.1107/S1600536813011410

organic compounds

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ISSN: 2056-9890

Volume 69| Part 6| June 2013| Page o897

doi:10.1107/S1600536813011410

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5-Methyl-3-phenylisoxazole-4-carboxylic acid

Chandra,^a N. Srikantamurthy,^b G. J. Vishalakshi,^a S. Jeyaseelan,^c K. B. Umesha ^b and M. Mahendra ^a ^*

^aDepartment of Studies in Physics, Manasagangotri, University of Mysore, Mysore 570 006, India, ^bDepartment of Chemistry, Yuvaraja's College, University of Mysore, Mysore 570 005, India, and ^cDepartment of Physics, St Philomena's College, Mysore, India
^*Correspondence e-mail: mahendra@physics.uni-mysore.ac.in

(Received 3 April 2013; accepted 26 April 2013; online 15 May 2013)

In the title compound, C₁₁H₉NO₃, the phenyl and isoxazole rings form a dihedral angle of 56.64 (8)°. The carboxy group is almost in the same plane as the isoxazole ring with a C—C—C—O torsion angle of −3.3 (2)°. In the crystal, pairs of O—H⋯O hydrogen bonds link the molecules into head-to-head dimers. C—H⋯N hydrogen bonds and π–π stacking interactions between phenyl rings [centroid–centroid distance = 3.9614 (17)Å] link the dimers into a three-dimensional network.

Related literature

For the biological and pharmaceutical importance of isoxazoles, see: Basappa et al., (2003 ); Conti et al. (1998 ); Kang et al. (2000 ); Lee et al. (2009 ); Shin et al. (2005 ); Stevens & Albizati (1984 ). For bond-length and angle data in related structures, see: Wolf et al. (1995 ); Chandra et al., (2013 ).

Experimental

Crystal data

C₁₁H₉NO₃
M_r = 203.19
Monoclinic, P 2₁ /n
a = 11.953 (4) Å
b = 5.981 (2) Å
c = 14.142 (5) Å
β = 105.548 (6)°
V = 974.0 (6) Å³
Z = 4
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 273 K
0.30 × 0.25 × 0.20 mm

Data collection

Bruker APEXII CCD area-detector diffractometer
8619 measured reflections
1712 independent reflections
1558 reflections with I > 2σ(I)
R_int = 0.026

Refinement

R[F² > 2σ(F²)] = 0.039
wR(F²) = 0.111
S = 1.05
1712 reflections
138 parameters
H-atom parameters constrained
Δρ_max = 0.19 e Å⁻³
Δρ_min = −0.14 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O14—H14⋯O15ⁱ	0.82	1.81	2.6252 (18)	172
C11—H11A⋯N8ⁱⁱ	0.96	2.51	3.427 (2)	159
Symmetry codes: (i) -x+2, -y, -z; (ii) $[-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z-{\script{1\over 2}}]$ .

Data collection: APEX2 (Bruker, 2009 ); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536813011410/bg2504sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813011410/bg2504Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536813011410/bg2504Isup3.cml

checkCIF report

Comment top

Isoxazole derivatives bearing various substituents are known to have diverse biological and pharmaceutical activities; such as anti-tumor (Kang et al., 2000), antiviral (Lee et al., 2009), hypoglycemic (Conti et al., 1998), antifungal (Basappa et al., 2003) and anti-HIV activities (Shin et al., 2005). In addition, isoxazoles and related compounds have attracted much interest because of their fungicidal, plant-growth regulating and antibacterial activities (Stevens & Albizati, 1984). As part of our interest in these compounds and our extensive background on isoxazole derivatives, we have synthesized the title compound to study its crystal structure.

Fig. 1 presents an ellipsoid plot of the title compound (I). The (C7/N8/O9/C10/C12) isoxazole ring is in Syn-Clinal conformation with respect to the (C1-C2-C3-C4-C5-C6) phenyl ring, as indicated by the (C1-C6-C7-N8) torsion angle of -54.40 (19)°. The carboxylic acid group at C12 is almost in the same plane as the isoxazole ring (C7-C12-C13-O15 torsion angle = -3.3 (2)°). The bond lengths and angles are within normal ranges and are comparable to related structure (Wolf et al., 1995 & Chandra et al., 2013). The crystal structure is stabilized by O—H···O bonds (Table 1), which define head to head dimers, and weaker C-H···N bonds (Table 1), thus defining planes parallel to (101) (Fig 2). Finally, there are π···π stacking interacions between phenyl rings with Cg···Cg[1-x,1-y,-z] and slippage displacement distances of 3.9614 (17)Å and 1.284Å respectively (Fig 3) which link planes into a 3D structure.

Related literature top

For the biological and pharmaceutical importance of isoxazoles, see: Basappa et al., (2003); Conti et al. (1998); Kang et al. (2000); Lee et al. (2009); Shin et al. (2005); Stevens & Albizati (1984). For bond-length and angle data in related structures, see: Wolf et al. (1995); Chandra et al., (2013).

Experimental top

A mixture of benzaldehyde oxime (1 mmol), ethyl acetoacetate (2 mmol) and anhydrous zinc chloride (0.1 mmol) were taken in a 10 ml round bottomed flask and the contents were gradually heated to 60°C without any solvent for about one hour. After completion of the reaction (as indicated by TLC), the mixture was cooled to room temperature and ethanol was added with stirring for about 30 min. The solid ethyl 5-methyl-3-phenylisoxazole-4-carboxylate thus obtained was treated with 5% NaOH (10 ml) at room temperature for about 4hr. After completion of the reaction (as indicated by TLC), the reaction mixture was acidified with 2 N HCl. The solids thus obtained were filtered and recrystalized from hot ethanol to get crystals of the title compound.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. Perspective diagram of the molecule with 50% probability displacement ellipsoids.
	Fig. 2. Packing diagram of the molecule viewed down the 'b' axis, showing the H-bonded dimers.
	Fig. 3. Packing diagram of the molecule viewed down the 'b' axis, showing the π–π interactions.

5-Methyl-3-phenylisoxazole-4-carboxylic acid top

Crystal data top

C₁₁H₉NO₃	F(000) = 424
M_r = 203.19	D_x = 1.386 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 1712 reflections
a = 11.953 (4) Å	θ = 2.0–25.0°
b = 5.981 (2) Å	µ = 0.10 mm⁻¹
c = 14.142 (5) Å	T = 273 K
β = 105.548 (6)°	Block, yellow
V = 974.0 (6) Å³	0.30 × 0.25 × 0.20 mm
Z = 4

Data collection top

Bruker APEXII CCD area-detector diffractometer	R_int = 0.026
ω and ϕ scans	θ_max = 25.0°, θ_min = 2.0°
8619 measured reflections	h = −14→14
1712 independent reflections	k = −7→7
1558 reflections with I > 2σ(I)	l = −16→16

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.039	H-atom parameters constrained
wR(F²) = 0.111	w = 1/[σ²(F_o²) + (0.0647P)² + 0.1799P] where P = (F_o² + 2F_c²)/3
S = 1.05	(Δ/σ)_max = 0.001
1712 reflections	Δρ_max = 0.19 e Å⁻³
138 parameters	Δρ_min = −0.14 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), FC^*=KFC[1+0.001XFC²Λ³/SIN(2Θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.078 (6)

Crystal data top

C₁₁H₉NO₃	V = 974.0 (6) Å³
M_r = 203.19	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 11.953 (4) Å	µ = 0.10 mm⁻¹
b = 5.981 (2) Å	T = 273 K
c = 14.142 (5) Å	0.30 × 0.25 × 0.20 mm
β = 105.548 (6)°

Data collection top

Bruker APEXII CCD area-detector diffractometer	1558 reflections with I > 2σ(I)
8619 measured reflections	R_int = 0.026
1712 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.039	0 restraints
wR(F²) = 0.111	H-atom parameters constrained
S = 1.05	Δρ_max = 0.19 e Å⁻³
1712 reflections	Δρ_min = −0.14 e Å⁻³
138 parameters

Special details top

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 on F² for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The observed criterion of F² > σ(F²) is used only for calculating -R-factor-obs 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

	x	y	z	U_iso*/U_eq
O9	0.78858 (10)	0.77608 (19)	−0.16618 (8)	0.0644 (4)
O14	0.98209 (9)	0.19333 (19)	−0.09796 (8)	0.0626 (4)
O15	0.89662 (9)	0.16156 (18)	0.02382 (7)	0.0583 (4)
N8	0.72219 (12)	0.7544 (2)	−0.09692 (10)	0.0627 (5)
C1	0.70696 (13)	0.6540 (3)	0.10434 (12)	0.0577 (5)
C2	0.65298 (14)	0.6027 (3)	0.17680 (13)	0.0667 (6)
C3	0.59319 (14)	0.4050 (3)	0.17315 (12)	0.0646 (6)
C4	0.58949 (14)	0.2546 (3)	0.09855 (13)	0.0634 (5)
C5	0.64525 (13)	0.3017 (3)	0.02718 (11)	0.0556 (5)
C6	0.70323 (11)	0.5035 (2)	0.02904 (9)	0.0458 (4)
C7	0.75633 (11)	0.5675 (2)	−0.05041 (10)	0.0465 (4)
C10	0.85935 (12)	0.6006 (2)	−0.15866 (10)	0.0503 (4)
C11	0.93670 (14)	0.6030 (3)	−0.22477 (11)	0.0643 (6)
C12	0.84386 (10)	0.4605 (2)	−0.08704 (9)	0.0445 (4)
C13	0.90974 (11)	0.2583 (2)	−0.05073 (10)	0.0454 (4)
H1	0.74570	0.78940	0.10620	0.0690*
H2	0.65710	0.70230	0.22810	0.0800*
H3	0.55530	0.37280	0.22100	0.0780*
H4	0.54920	0.12080	0.09630	0.0760*
H5	0.64400	0.19820	−0.02220	0.0670*
H11A	0.91180	0.49090	−0.27460	0.0960*
H11B	1.01490	0.57240	−0.18750	0.0960*
H11C	0.93350	0.74740	−0.25510	0.0960*
H14	1.01490	0.07930	−0.07260	0.0940*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O9	0.0729 (7)	0.0625 (7)	0.0640 (7)	0.0040 (5)	0.0289 (6)	0.0164 (5)
O14	0.0661 (7)	0.0664 (7)	0.0657 (7)	0.0140 (5)	0.0357 (5)	0.0054 (5)
O15	0.0618 (6)	0.0630 (7)	0.0569 (6)	0.0092 (5)	0.0275 (5)	0.0080 (5)
N8	0.0654 (8)	0.0622 (8)	0.0683 (8)	0.0096 (6)	0.0312 (7)	0.0138 (6)
C1	0.0544 (8)	0.0569 (9)	0.0676 (9)	−0.0019 (7)	0.0264 (7)	−0.0099 (7)
C2	0.0636 (9)	0.0795 (11)	0.0660 (10)	0.0025 (8)	0.0328 (8)	−0.0163 (8)
C3	0.0604 (9)	0.0801 (11)	0.0630 (9)	0.0064 (8)	0.0332 (7)	0.0068 (8)
C4	0.0634 (9)	0.0615 (9)	0.0722 (10)	−0.0058 (7)	0.0304 (8)	0.0056 (8)
C5	0.0597 (9)	0.0553 (9)	0.0559 (8)	−0.0029 (7)	0.0226 (7)	−0.0044 (7)
C6	0.0397 (7)	0.0511 (8)	0.0488 (7)	0.0059 (5)	0.0155 (5)	0.0022 (6)
C7	0.0442 (7)	0.0481 (7)	0.0483 (7)	−0.0006 (6)	0.0142 (6)	0.0001 (6)
C10	0.0513 (7)	0.0547 (8)	0.0459 (7)	−0.0069 (6)	0.0147 (6)	−0.0019 (6)
C11	0.0708 (10)	0.0761 (11)	0.0535 (9)	−0.0162 (8)	0.0297 (8)	−0.0023 (7)
C12	0.0430 (7)	0.0496 (7)	0.0425 (7)	−0.0052 (5)	0.0145 (5)	−0.0040 (5)
C13	0.0432 (7)	0.0510 (8)	0.0449 (7)	−0.0037 (5)	0.0169 (5)	−0.0059 (6)

Geometric parameters (Å, º) top

O9—N8	1.4222 (19)	C7—C12	1.4363 (19)
O9—C10	1.3342 (18)	C10—C12	1.3649 (19)
O14—C13	1.2863 (18)	C10—C11	1.481 (2)
O15—C13	1.2488 (17)	C12—C13	1.4593 (18)
O14—H14	0.8200	C1—H1	0.9300
N8—C7	1.3057 (18)	C2—H2	0.9300
C1—C2	1.384 (2)	C3—H3	0.9300
C1—C6	1.386 (2)	C4—H4	0.9300
C2—C3	1.375 (3)	C5—H5	0.9300
C3—C4	1.378 (3)	C11—H11A	0.9600
C4—C5	1.380 (2)	C11—H11B	0.9600
C5—C6	1.389 (2)	C11—H11C	0.9600
C6—C7	1.4813 (19)

O9···C10ⁱ	3.268 (2)	C10···O15ⁱⁱⁱ	3.345 (2)
O9···C11ⁱ	3.351 (2)	C10···C13ⁱⁱⁱ	3.566 (2)
O14···O15ⁱⁱ	2.6252 (18)	C11···O14	2.999 (2)
O14···C11	2.999 (2)	C11···O9^iv	3.351 (2)
O15···C11ⁱⁱⁱ	3.316 (2)	C11···N8^iv	3.427 (2)
O15···O14ⁱⁱ	2.6252 (18)	C11···O15ⁱⁱⁱ	3.316 (2)
O15···C13ⁱⁱ	3.367 (2)	C12···C13ⁱⁱⁱ	3.496 (2)
O15···C5	3.132 (2)	C13···O15ⁱⁱ	3.367 (2)
O15···C6	3.102 (2)	C13···C10ⁱⁱⁱ	3.566 (2)
O15···C10ⁱⁱⁱ	3.345 (2)	C13···C12ⁱⁱⁱ	3.496 (2)
O9···H11Aⁱ	2.6500	C13···H14ⁱⁱ	2.6600
O14···H11B	2.6800	H1···N8	2.8200
O14···H14ⁱⁱ	2.9000	H11A···O9^iv	2.6500
O15···H11Bⁱⁱⁱ	2.7700	H11A···N8^iv	2.5100
O15···H14ⁱⁱ	1.8100	H11B···O14	2.6800
N8···C11ⁱ	3.427 (2)	H11B···O15ⁱⁱⁱ	2.7700
N8···H1	2.8200	H14···O14ⁱⁱ	2.9000
N8···H11Aⁱ	2.5100	H14···O15ⁱⁱ	1.8100
C5···O15	3.132 (2)	H14···C13ⁱⁱ	2.6600
C6···O15	3.102 (2)	H14···H14ⁱⁱ	2.3700
C10···O9^iv	3.268 (2)

N8—O9—C10	109.41 (11)	O14—C13—C12	116.24 (12)
C13—O14—H14	109.00	O15—C13—C12	120.20 (12)
O9—N8—C7	105.56 (12)	O14—C13—O15	123.54 (12)
C2—C1—C6	119.97 (16)	C2—C1—H1	120.00
C1—C2—C3	120.23 (16)	C6—C1—H1	120.00
C2—C3—C4	119.98 (16)	C1—C2—H2	120.00
C3—C4—C5	120.28 (16)	C3—C2—H2	120.00
C4—C5—C6	120.02 (15)	C2—C3—H3	120.00
C1—C6—C7	118.88 (12)	C4—C3—H3	120.00
C5—C6—C7	121.56 (12)	C3—C4—H4	120.00
C1—C6—C5	119.49 (13)	C5—C4—H4	120.00
N8—C7—C6	117.63 (12)	C4—C5—H5	120.00
N8—C7—C12	111.06 (12)	C6—C5—H5	120.00
C6—C7—C12	131.31 (11)	C10—C11—H11A	109.00
O9—C10—C11	115.59 (12)	C10—C11—H11B	109.00
O9—C10—C12	109.44 (12)	C10—C11—H11C	110.00
C11—C10—C12	134.94 (13)	H11A—C11—H11B	110.00
C7—C12—C13	128.23 (11)	H11A—C11—H11C	109.00
C10—C12—C13	127.03 (12)	H11B—C11—H11C	109.00
C7—C12—C10	104.53 (11)

C10—O9—N8—C7	0.33 (15)	C1—C6—C7—C12	124.36 (16)
N8—O9—C10—C11	−178.39 (12)	C5—C6—C7—N8	122.44 (15)
N8—O9—C10—C12	−0.04 (15)	N8—C7—C12—C10	0.45 (16)
O9—N8—C7—C12	−0.47 (15)	N8—C7—C12—C13	175.43 (13)
O9—N8—C7—C6	178.53 (11)	C6—C7—C12—C10	−178.37 (14)
C2—C1—C6—C5	−0.1 (2)	C6—C7—C12—C13	−3.4 (2)
C6—C1—C2—C3	−1.6 (3)	O9—C10—C12—C7	−0.23 (15)
C2—C1—C6—C7	176.80 (14)	O9—C10—C12—C13	−175.28 (12)
C1—C2—C3—C4	1.7 (3)	C11—C10—C12—C7	177.67 (16)
C2—C3—C4—C5	−0.2 (3)	C11—C10—C12—C13	2.6 (3)
C3—C4—C5—C6	−1.5 (3)	C7—C12—C13—O14	178.55 (13)
C4—C5—C6—C7	−175.22 (14)	C7—C12—C13—O15	−3.3 (2)
C4—C5—C6—C1	1.6 (2)	C10—C12—C13—O14	−7.5 (2)
C1—C6—C7—N8	−54.40 (19)	C10—C12—C13—O15	170.61 (13)
C5—C6—C7—C12	−58.8 (2)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O14—H14···O15ⁱⁱ	0.82	1.81	2.6252 (18)	172
C11—H11A···N8^iv	0.96	2.51	3.427 (2)	159

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

Experimental details

Crystal data
Chemical formula	C₁₁H₉NO₃
M_r	203.19
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	273
a, b, c (Å)	11.953 (4), 5.981 (2), 14.142 (5)
β (°)	105.548 (6)
V (Å³)	974.0 (6)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.10
Crystal size (mm)	0.30 × 0.25 × 0.20

Data collection
Diffractometer	Bruker APEXII CCD area-detector diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	8619, 1712, 1558
R_int	0.026
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.039, 0.111, 1.05
No. of reflections	1712
No. of parameters	138
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.19, −0.14

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O14—H14···O15ⁱ	0.8200	1.8100	2.6252 (18)	172.00
C11—H11A···N8ⁱⁱ	0.9600	2.5100	3.427 (2)	159.00

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

Acknowledgements

The authors would like to thank the UGC, New Delhi, Government of India, for awarding a project under the head F·No.41–920/2012(SR) dated: 25–07-2012.

References

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