Methyl 3-phenyl­isoxazole-5-carboxyl­ate

In the title compound, C₁₁H₉NO₃, the dihedral angle between the isoxazole and phenyl rings is 19.79 (12), while the ester group is inclined to the isoxazole group by 12.14 (6)°. In the crystal, mol­ecules are linked by C—H...O hydrogen bonds, forming layers lying parallel to (010).

Key indicators

• Single-crystal X-ray study
• T = 296 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.059
• wR factor = 0.133
• Data-to-parameter ratio = 12.4

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT031_ALERT_4_C Refined Extinction Parameter within Range ......      2.579 Sigma
PLAT906_ALERT_3_C Large K value in the Analysis of Variance ......     11.648 Check
PLAT906_ALERT_3_C Large K value in the Analysis of Variance ......      2.994 Check
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.596          4

Alert level G
PLAT005_ALERT_5_G No _iucr_refine_instructions_details  in the CIF     Please Do !
PLAT909_ALERT_3_G Percentage of Observed Data at Theta(Max) still          40 %

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   4 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   2 ALERT level G = General information/check it is not something unexpected

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   4 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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S1. Comment

The wide occurrence of heterocycles, such as isoxazoles, in bioactive natural products, pharmaceuticals and agrochemicals has made them important synthetic targets. They are of great importance in biological chemistry, showing anticancer activity, and substituted isoxazoles have revealed antibacterial, antioxidant, insecticidal properties (Musad et al., 2011). Here we report on the crystal structure of the title isoxazole derivative, synthesized by alcoholysis of 3-Phenyl-isoxazole-5-carbonyl chloride in dichloromethane.

In the molecule of the title compound, Fig. 1, the dihedral angle between the phenyl and the isoxazole rings is 19.79 (12) °. This is larger than that of 7.37 (19)° observed in the related compound Isopropyl 3-phenylisoxazole-5-carboxylate (Wang et al., 2013), but the bond lengths within the isoxazole ring are the same.

In the crystal, molecules are linked by C—H···O hydrogen bonds (Table 1), forming layers lying parallel to (010).

Related literature

For the biological activity of isoxazole derivatives, see: Musad et al. (2011). For the synthesis and the structure of a related compound, see: Wang et al. (2013).

S2. Experimental

3-Phenylisoxazole-5-carboxylic acid (10 mmol, 1.95 g; Wang et al., 2013) was dissolved in 100 ml dichloromethane, then thionyl chloride (12 mmol, 1.43 g) was added drop wise while the solution was stirred for 20 minutes in an ice bath. The solvent was removed under reduced pressure and the mixture was used for the next step without further purification. Methanol (20 mmol, 0.64 g) was then added and the mixture stirred for 6 h at room temperature. The resulting residue was purified as a white solid (1.54 g; 76% yield). Recrystallization in dichloromethane gave fine colourless plate-like crystals suitable for X-ray diffraction analysis.

S3. Refinement

All H atoms were placed in idealized positions and allowed to ride on the respective parent atom: C—H = 0.93–0.96 Å with U_iso(H) = 1.5U_eq(C-methyl) and = 1.2U_eq(C) for other H atoms.

Computing details

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009) and publCIF (Westrip, 2010).

Figures

Fig. 1. The molecular structure of the title molecule, with atom labelling. Displacement ellipsoids are drawn at the 30% probability level. H atoms have been omitted for clarity.

Methyl 3-phenylisoxazole-5-carboxylate

Crystal data

C11H9NO3	Z = 4
Mr = 203.19	F(000) = 424
Monoclinic, P21/c	Dx = 1.392 Mg m^−3
Hall symbol: -P 2ybc	Mo Kα radiation, λ = 0.71073 Å
a = 12.2275 (18) Å	θ = 1.7–25.1°
b = 13.604 (2) Å	µ = 0.10 mm^−1
c = 5.8746 (9) Å	T = 296 K
β = 97.011 (3)°	Plate, colourless
V = 969.9 (3) Å^3	0.36 × 0.25 × 0.13 mm

Data collection

Bruker APEXII CCD diffractometer	1718 independent reflections
Radiation source: fine-focus sealed tube	1238 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.036
phi and ω scans	θmax = 25.1°, θmin = 1.7°
Absorption correction: multi-scan (SADABS; Bruker, 2008)	h = −14→10
Tmin = 0.964, Tmax = 0.987	k = −15→16
4807 measured reflections	l = −6→7

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.059	H-atom parameters constrained
wR(F^2) = 0.133	w = 1/[σ^2(Fo^2) + (0.0531P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 1.13	(Δ/σ)max < 0.001
1718 reflections	Δρmax = 0.17 e Å^−3
138 parameters	Δρmin = −0.15 e Å^−3
0 restraints	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0049 (19)

Special details

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
N1	0.58165 (16)	0.12445 (15)	0.1263 (4)	0.0548 (6)
O1	0.69685 (13)	0.12779 (12)	0.1714 (3)	0.0568 (5)
O2	0.91297 (15)	0.11346 (15)	0.3629 (3)	0.0734 (7)
O3	0.85964 (13)	0.14679 (13)	0.7065 (3)	0.0601 (5)
C1	0.3828 (2)	0.15075 (17)	0.5374 (4)	0.0497 (7)
H1	0.4298	0.1742	0.6620	0.060*
C2	0.2707 (2)	0.14652 (19)	0.5489 (5)	0.0581 (7)
H2	0.2426	0.1677	0.6807	0.070*
C3	0.2004 (2)	0.11121 (19)	0.3669 (5)	0.0593 (8)
H3	0.1249	0.1088	0.3746	0.071*
C4	0.2428 (2)	0.07947 (19)	0.1727 (5)	0.0585 (7)
H4	0.1956	0.0546	0.0501	0.070*
C5	0.35431 (19)	0.08422 (18)	0.1585 (4)	0.0495 (7)
H5	0.3820	0.0632	0.0261	0.059*
C6	0.42544 (18)	0.12036 (15)	0.3418 (4)	0.0419 (6)
C7	0.54474 (18)	0.12641 (15)	0.3261 (4)	0.0404 (6)
C9	0.72372 (19)	0.13278 (17)	0.4011 (4)	0.0447 (6)
C10	0.63299 (18)	0.13246 (16)	0.5065 (4)	0.0451 (6)
H10	0.6286	0.1355	0.6633	0.054*
C11	0.8426 (2)	0.13030 (18)	0.4824 (5)	0.0511 (7)
C12	0.9720 (2)	0.1372 (2)	0.8127 (5)	0.0722 (9)
H12A	1.0015	0.0755	0.7694	0.108*
H12B	0.9737	0.1397	0.9764	0.108*
H12C	1.0154	0.1900	0.7629	0.108*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N1	0.0377 (12)	0.0773 (16)	0.0498 (14)	−0.0009 (10)	0.0068 (10)	−0.0028 (11)
O1	0.0444 (11)	0.0800 (13)	0.0475 (11)	−0.0009 (9)	0.0119 (8)	−0.0010 (9)
O2	0.0451 (11)	0.1176 (18)	0.0603 (13)	0.0086 (11)	0.0184 (9)	0.0003 (11)
O3	0.0400 (10)	0.0877 (14)	0.0523 (12)	0.0010 (9)	0.0044 (8)	−0.0068 (10)
C1	0.0448 (15)	0.0555 (16)	0.0492 (16)	−0.0026 (12)	0.0074 (12)	−0.0066 (12)
C2	0.0490 (17)	0.0677 (18)	0.0603 (18)	0.0044 (13)	0.0173 (13)	−0.0047 (14)
C3	0.0363 (14)	0.0689 (19)	0.073 (2)	0.0013 (13)	0.0078 (14)	0.0140 (15)
C4	0.0425 (16)	0.0702 (18)	0.0598 (19)	−0.0053 (13)	−0.0062 (13)	0.0057 (14)
C5	0.0455 (15)	0.0563 (15)	0.0466 (16)	0.0009 (12)	0.0054 (12)	−0.0007 (12)
C6	0.0406 (14)	0.0411 (13)	0.0438 (14)	0.0013 (10)	0.0039 (11)	0.0035 (11)
C7	0.0412 (14)	0.0371 (13)	0.0427 (14)	0.0005 (10)	0.0040 (11)	−0.0020 (11)
C9	0.0441 (15)	0.0497 (15)	0.0405 (14)	−0.0008 (11)	0.0057 (11)	0.0024 (11)
C10	0.0427 (14)	0.0525 (15)	0.0407 (14)	0.0043 (12)	0.0075 (11)	−0.0007 (11)
C11	0.0451 (16)	0.0565 (16)	0.0529 (17)	0.0014 (12)	0.0108 (13)	0.0010 (13)
C12	0.0457 (17)	0.104 (2)	0.0639 (19)	0.0039 (15)	−0.0067 (14)	−0.0015 (17)

Geometric parameters (Å, º)

N1—C7	1.308 (3)	C4—C5	1.378 (3)
N1—O1	1.402 (2)	C4—H4	0.9300
O1—C9	1.351 (3)	C5—C6	1.389 (3)
O2—C11	1.197 (3)	C5—H5	0.9300
O3—C11	1.326 (3)	C6—C7	1.475 (3)
O3—C12	1.443 (3)	C7—C10	1.420 (3)
C1—C6	1.382 (3)	C9—C10	1.335 (3)
C1—C2	1.382 (3)	C9—C11	1.474 (3)
C1—H1	0.9300	C10—H10	0.9300
C2—C3	1.374 (4)	C12—H12A	0.9600
C2—H2	0.9300	C12—H12B	0.9600
C3—C4	1.379 (4)	C12—H12C	0.9600
C3—H3	0.9300
C7—N1—O1	106.16 (18)	C5—C6—C7	120.1 (2)
C9—O1—N1	107.86 (17)	N1—C7—C10	110.9 (2)
C11—O3—C12	116.1 (2)	N1—C7—C6	120.5 (2)
C6—C1—C2	120.3 (2)	C10—C7—C6	128.6 (2)
C6—C1—H1	119.8	C10—C9—O1	110.4 (2)
C2—C1—H1	119.8	C10—C9—C11	133.8 (2)
C3—C2—C1	120.4 (3)	O1—C9—C11	115.6 (2)
C3—C2—H2	119.8	C9—C10—C7	104.6 (2)
C1—C2—H2	119.8	C9—C10—H10	127.7
C2—C3—C4	119.4 (2)	C7—C10—H10	127.7
C2—C3—H3	120.3	O2—C11—O3	125.2 (2)
C4—C3—H3	120.3	O2—C11—C9	124.4 (3)
C5—C4—C3	120.7 (2)	O3—C11—C9	110.3 (2)
C5—C4—H4	119.7	O3—C12—H12A	109.5
C3—C4—H4	119.7	O3—C12—H12B	109.5
C4—C5—C6	120.0 (2)	H12A—C12—H12B	109.5
C4—C5—H5	120.0	O3—C12—H12C	109.5
C6—C5—H5	120.0	H12A—C12—H12C	109.5
C1—C6—C5	119.1 (2)	H12B—C12—H12C	109.5
C1—C6—C7	120.8 (2)
C7—N1—O1—C9	−0.7 (3)	C5—C6—C7—C10	−159.5 (2)
C6—C1—C2—C3	0.6 (4)	N1—O1—C9—C10	0.2 (3)
C1—C2—C3—C4	0.3 (4)	N1—O1—C9—C11	176.1 (2)
C2—C3—C4—C5	−1.0 (4)	O1—C9—C10—C7	0.2 (3)
C3—C4—C5—C6	0.7 (4)	C11—C9—C10—C7	−174.6 (3)
C2—C1—C6—C5	−0.9 (3)	N1—C7—C10—C9	−0.7 (3)
C2—C1—C6—C7	178.8 (2)	C6—C7—C10—C9	177.9 (2)
C4—C5—C6—C1	0.3 (3)	C12—O3—C11—O2	−4.0 (4)
C4—C5—C6—C7	−179.4 (2)	C12—O3—C11—C9	174.4 (2)
O1—N1—C7—C10	0.8 (3)	C10—C9—C11—O2	166.0 (3)
O1—N1—C7—C6	−177.87 (18)	O1—C9—C11—O2	−8.7 (4)
C1—C6—C7—N1	−160.8 (2)	C10—C9—C11—O3	−12.4 (4)
C5—C6—C7—N1	18.9 (3)	O1—C9—C11—O3	172.9 (2)
C1—C6—C7—C10	20.8 (4)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C3—H3···O2^i	0.93	2.58	3.512 (3)	175
C12—H12B···O2^ii	0.96	2.50	3.412 (3)	159

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