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

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ISSN: 2056-9890

3-(4-Chloro­phen­yl)-5-phenyl-4,5-di­hydro-1,3-oxazole

aNational Institute of Technology-Karnataka, Department of Chemistry, Medicinal Chemistry Laboratory, Surathkal, Mangalore 575 025, India, and bNelson Mandela Metropolitan University, Summerstrand Campus, Department of Chemistry, University Way, Summerstrand, PO Box 77000, Port Elizabeth, 6031, South Africa
*Correspondence e-mail: richard.betz@webmail.co.za

(Received 9 October 2012; accepted 22 October 2012; online 27 October 2012)

In the title compound, C15H12ClNO, the isoxazoline ring adopts an envelope conformation with the C atom bearing an unsubstituted phenyl ring as the flap atom. The chlorinated phenyl group is nearly in-plane with the four coplanar atoms of the heterocycle and the corresponding mean planes enclosing an angle of 1.16 (7)°. The unsubstituted phenyl group attached to the envelope flap atom approaches a nearly perpendicular orientation relative to the isoxazoline ring with a dihedral angle of 74.93 (7)°. In the crystal, weak C—H⋯O, C—H⋯N and C—H⋯π inter­actions connect the mol­ecules into layers perpendicular to the a axis.

Related literature

For the biological and medicinal importance of isoxazole compounds, see: Miller et al. (2009[Miller, J. J., Rajaram, S., Pfaffenroth, C. & Sigman, M. S. (2009). Tetrahedron, 65, 3110-3119.]); Prasad et al. (2007[Prasad, Y. R., Kumar, P. R. & Ramesh, B. (2007). Int. J. Chem. Sci. 5, 542-548.]). For their use in ring-opening polymerizations, see: Wiesbrock et al. (2005[Wiesbrock, F., Hoogenboom, R., Leenen, M. A. M., Meier, M. A. R. & Schubert, U. S. (2005). Macromolecules, 38, 5025-5034.]). For the puckering analysis of five-membered rings, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]). For graph-set analysis of hydrogen bonds, see: Etter et al. (1990[Etter, M. C., MacDonald, J. C. & Bernstein, J. (1990). Acta Cryst. B46, 256-262.]); Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data
  • C15H12ClNO

  • Mr = 257.71

  • Monoclinic, C 2/c

  • a = 29.797 (5) Å

  • b = 10.717 (5) Å

  • c = 8.086 (5) Å

  • β = 103.088 (5)°

  • V = 2515 (2) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.29 mm−1

  • T = 200 K

  • 0.58 × 0.42 × 0.21 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2008[Bruker (2008). SADABS. Bruker Inc., Madison, Wisconsin, USA.]) Tmin = 0.850, Tmax = 0.943

  • 11843 measured reflections

  • 3132 independent reflections

  • 2637 reflections with I > 2σ(I)

  • Rint = 0.014

Refinement
  • R[F2 > 2σ(F2)] = 0.037

  • wR(F2) = 0.103

  • S = 1.03

  • 3132 reflections

  • 163 parameters

  • H-atom parameters constrained

  • Δρmax = 0.31 e Å−3

  • Δρmin = −0.23 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg is the centroid of the C11–C16 ring.

D—H⋯A D—H H⋯A DA D—H⋯A
C12—H12⋯N1i 0.95 2.74 3.657 (2) 163
C12—H12⋯O1i 0.95 2.65 3.390 (2) 135
C2—H2B⋯O1ii 0.99 2.67 3.466 (2) 138
C26—H26⋯O1ii 0.95 2.70 3.431 (2) 134
C22—H22⋯Cgiii 0.95 2.81 3.721 (3) 162
Symmetry codes: (i) [-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]; (ii) [x, -y, z-{\script{1\over 2}}]; (iii) [-x+{\script{1\over 2}}, -y+{\script{1\over 2}}, -z+1].

Data collection: APEX2 (Bruker, 2010[Bruker (2010). APEX2 and SAINT. Bruker AXS Inc., Madison, USA.]); cell refinement: SAINT (Bruker, 2010[Bruker (2010). APEX2 and SAINT. Bruker AXS Inc., Madison, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and Mercury (Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Isoxazoles are well known organic compounds which are included in a variety of complex biologically active structures and play a role as catalyst, ligands and intermediates for functional compounds (Miller et al., 2009; Prasad et al., 2007). Isoxazoles appear in numerous medicinally active compounds and natural products of biological significance. Additionally, they are valuable as synthetic intermediates or protecting groups in organic synthesis. Also, isoxazoles serve as monomers for the synthesis of substituted poly(imine)s by cationic ring-opening polymerization (Wiesbrock et al., 2005). Due to our interest in developing new isoxazole-based heterocycles, we have synthesized the title compound to study its crystal structure.

The title molecule features a chlorinated as well as a non-halogenated phenyl group as substituents on a central isoxazole core. The latter one adopts a 5E conformation with the flap atom on C3 (Cremer & Pople, 1975). While the halogenated phenyl group is nearly in-plane with the isoxazoline moiety – the least-squares planes defined by the respective intracyclic atoms intersect at an angle of 7.16 (7) ° only – the non-substituted phenyl group adopts a nearly perpendicular orientation towards the isoxazole moiety. The corresponding least-squares planes in the latter case enclose an angle of 74.93 (7) ° (Fig. 1).

In the crystal, only weak C–H···O and C–H···N contacts whose range falls slightly below the sum of van-der-Waals radii of the atoms participating in them are observed. The hydrogen atom that is part of the C–H···N contact stems from the chlorinated phenyl substituent and is also the origin of a bifuracated hydrogen bond that extends to the oxygen atom as acceptor. The C–H···O contacts are supported by the intracyclic methylene group as well as a hydrogen atom on the non-substituted phenyl group. Taking into account the latter two findings, the oxygen atom acts as threefold acceptor. Metrical parameters as well as information about the symmetry codes for these contacts are summarized in Table 1. In total, the molecules are connected to layers perpendicular to the crystallographic a axis. In terms of graph-set analysis (Etter et al., 1990; Bernstein et al., 1995), the descriptor for these contacts is C11(4)C11(5)C11(5)C11(6) on the unary level. The shortest intercentroid distance between two aromatic systems was measured at 4.709 (3) Å and is observed between the halogenated phenyl group and its symmetry-generated equivalent (Fig. 2).

The packing of the title compound in the crystal structure is shown in Figure 3.

Related literature top

For the biological and medicinal importance of isoxazole compounds, see: Miller et al. (2009); Prasad et al. (2007). For their use in ring-opening polymerizations, see: Wiesbrock et al. (2005). For the puckering analysis of five-membered rings, see: Cremer & Pople (1975). For graph-set analysis of hydrogen bonds, see: Etter et al. (1990); Bernstein et al. (1995).

Experimental top

An equimolar mixture of 1-(4-chlorophenyl)-N-hydroxymethanimine (0.5 g, 0.0032 mol), N-chloro succinamide (0.58 g, 0.0032 mol) and sodium bicarbonate (0.537 g, 0,0064 mol) in dichloromethane (10 ml) and water (10 ml) was stirred at 0 °C for 1 h. Styrene (0.366 g, 0.0035 mol) was then added to the reaction mixture and stirring was continued for another 12 h at room temperature. After completion of the reaction, the reaction mixture was concentrated and purified by column chromatography using petrol ether and ethyl acetate (v/v = 1:1) as the eluent to afford the title compound as a white solid, yield: 0.63 g (76.8%) (ChemSpider ID: 10496235).

Refinement top

Carbon-bound H atoms were placed in calculated positions (C—H 0.95 Å for aromatic carbon atoms, C—H 1.00 Å for methine groups and C—H 0.99 Å for methylene groups) and were included in the refinement in the riding model approximation, with U(H) set to 1.2Ueq(C).

Computing details top

Data collection: APEX2 (Bruker, 2010); cell refinement: SAINT (Bruker, 2010); data reduction: SAINT (Bruker, 2010); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, with anisotropic displacement ellipsoids drawn at the 50% probability level.
[Figure 2] Fig. 2. Intermolecular contacts, viewed approximately along [0 - 1 -1]. Symmetry operators: i x, -y, z + 1/2; ii -x + 1/2, y + 1/2, -z + 1/2.
[Figure 3] Fig. 3. Molecular packing of the title compound, viewed along [0 1 0] (anisotropic displacement ellipsoids drawn at 50% probability level).
3-(4-Chlorophenyl)-5-phenyl-4,5-dihydro-1,3-oxazole top
Crystal data top
C15H12ClNOF(000) = 1072
Mr = 257.71Dx = 1.361 Mg m3
Monoclinic, C2/cMelting point = 406–408 K
Hall symbol: -C 2ycMo Kα radiation, λ = 0.71069 Å
a = 29.797 (5) ÅCell parameters from 7100 reflections
b = 10.717 (5) Åθ = 2.8–28.3°
c = 8.086 (5) ŵ = 0.29 mm1
β = 103.088 (5)°T = 200 K
V = 2515 (2) Å3Block, colourless
Z = 80.58 × 0.42 × 0.21 mm
Data collection top
Bruker APEXII CCD
diffractometer
3132 independent reflections
Radiation source: fine-focus sealed tube2637 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.014
ϕ and ω scansθmax = 28.3°, θmin = 2.8°
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
h = 3939
Tmin = 0.850, Tmax = 0.943k = 1413
11843 measured reflectionsl = 109
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)] = 0.037Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.103H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.0463P)2 + 1.7436P]
where P = (Fo2 + 2Fc2)/3
3132 reflections(Δ/σ)max < 0.001
163 parametersΔρmax = 0.31 e Å3
0 restraintsΔρmin = 0.23 e Å3
Crystal data top
C15H12ClNOV = 2515 (2) Å3
Mr = 257.71Z = 8
Monoclinic, C2/cMo Kα radiation
a = 29.797 (5) ŵ = 0.29 mm1
b = 10.717 (5) ÅT = 200 K
c = 8.086 (5) Å0.58 × 0.42 × 0.21 mm
β = 103.088 (5)°
Data collection top
Bruker APEXII CCD
diffractometer
3132 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
2637 reflections with I > 2σ(I)
Tmin = 0.850, Tmax = 0.943Rint = 0.014
11843 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0370 restraints
wR(F2) = 0.103H-atom parameters constrained
S = 1.03Δρmax = 0.31 e Å3
3132 reflectionsΔρmin = 0.23 e Å3
163 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Cl10.047465 (13)0.13436 (5)0.07319 (6)0.06357 (16)
O10.30314 (3)0.00728 (10)0.48581 (13)0.0473 (3)
N10.25598 (4)0.00421 (12)0.40628 (16)0.0450 (3)
C10.24324 (4)0.09115 (11)0.31161 (15)0.0300 (2)
C20.28171 (4)0.18052 (11)0.30834 (17)0.0349 (3)
H2A0.27240.26800.32140.042*
H2B0.29310.17240.20290.042*
C30.31733 (5)0.13540 (12)0.46363 (16)0.0373 (3)
H30.31410.18570.56450.045*
C110.19537 (4)0.10199 (11)0.21455 (15)0.0295 (2)
C120.18093 (4)0.20517 (12)0.11130 (16)0.0346 (3)
H120.20250.26860.10170.042*
C130.13540 (5)0.21625 (13)0.02230 (17)0.0405 (3)
H130.12560.28690.04750.049*
C140.10459 (4)0.12302 (13)0.03681 (17)0.0389 (3)
C150.11790 (4)0.01975 (13)0.13904 (17)0.0388 (3)
H150.09620.04320.14840.047*
C160.16323 (4)0.00951 (12)0.22721 (17)0.0354 (3)
H160.17270.06120.29730.043*
C210.36712 (4)0.13532 (11)0.45344 (15)0.0321 (3)
C220.39722 (5)0.22193 (12)0.54584 (18)0.0409 (3)
H220.38640.28110.61510.049*
C230.44339 (5)0.22225 (14)0.5373 (2)0.0504 (4)
H230.46390.28250.59930.060*
C240.45938 (5)0.13514 (15)0.4389 (2)0.0491 (4)
H240.49090.13470.43390.059*
C250.42940 (5)0.04860 (15)0.3476 (2)0.0480 (3)
H250.44040.01130.27970.058*
C260.38362 (5)0.04870 (13)0.35468 (17)0.0399 (3)
H260.36320.01110.29130.048*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.03330 (19)0.0913 (3)0.0612 (3)0.01429 (18)0.00056 (16)0.0042 (2)
O10.0324 (5)0.0532 (6)0.0521 (6)0.0033 (4)0.0008 (4)0.0226 (5)
N10.0310 (6)0.0492 (7)0.0523 (7)0.0030 (5)0.0042 (5)0.0185 (6)
C10.0321 (6)0.0295 (5)0.0294 (5)0.0008 (4)0.0095 (4)0.0000 (4)
C20.0312 (6)0.0296 (6)0.0435 (7)0.0008 (5)0.0074 (5)0.0034 (5)
C30.0353 (6)0.0426 (7)0.0338 (6)0.0007 (5)0.0076 (5)0.0058 (5)
C110.0320 (5)0.0282 (5)0.0294 (5)0.0029 (4)0.0093 (4)0.0022 (4)
C120.0383 (6)0.0325 (6)0.0343 (6)0.0027 (5)0.0108 (5)0.0022 (5)
C130.0434 (7)0.0421 (7)0.0359 (6)0.0129 (6)0.0088 (5)0.0065 (5)
C140.0304 (6)0.0504 (7)0.0355 (6)0.0099 (5)0.0066 (5)0.0044 (6)
C150.0326 (6)0.0397 (7)0.0449 (7)0.0007 (5)0.0106 (5)0.0045 (5)
C160.0347 (6)0.0306 (6)0.0413 (6)0.0023 (5)0.0092 (5)0.0028 (5)
C210.0326 (6)0.0332 (6)0.0290 (5)0.0006 (4)0.0036 (4)0.0011 (5)
C220.0439 (7)0.0338 (6)0.0428 (7)0.0031 (5)0.0054 (5)0.0050 (5)
C230.0421 (8)0.0454 (8)0.0583 (9)0.0138 (6)0.0002 (6)0.0011 (7)
C240.0320 (7)0.0534 (9)0.0615 (9)0.0014 (6)0.0099 (6)0.0110 (7)
C250.0443 (8)0.0490 (8)0.0529 (8)0.0073 (6)0.0160 (6)0.0014 (7)
C260.0385 (7)0.0413 (7)0.0390 (7)0.0019 (5)0.0069 (5)0.0068 (6)
Geometric parameters (Å, º) top
Cl1—C141.7372 (14)C13—H130.9500
O1—N11.4121 (14)C14—C151.385 (2)
O1—C31.4597 (18)C15—C161.3816 (18)
N1—C11.2818 (17)C15—H150.9500
C1—C111.4688 (16)C16—H160.9500
C1—C21.4985 (17)C21—C261.3853 (19)
C2—C31.5277 (19)C21—C221.3859 (18)
C2—H2A0.9900C22—C231.393 (2)
C2—H2B0.9900C22—H220.9500
C3—C211.5043 (18)C23—C241.380 (2)
C3—H31.0000C23—H230.9500
C11—C121.3936 (17)C24—C251.380 (2)
C11—C161.3979 (18)C24—H240.9500
C12—C131.3893 (18)C25—C261.378 (2)
C12—H120.9500C25—H250.9500
C13—C141.380 (2)C26—H260.9500
N1—O1—C3108.20 (9)C13—C14—Cl1119.96 (11)
C1—N1—O1109.39 (10)C15—C14—Cl1118.45 (11)
N1—C1—C11120.17 (11)C16—C15—C14119.06 (12)
N1—C1—C2113.33 (11)C16—C15—H15120.5
C11—C1—C2126.46 (10)C14—C15—H15120.5
C1—C2—C3100.08 (10)C15—C16—C11120.79 (12)
C1—C2—H2A111.8C15—C16—H16119.6
C3—C2—H2A111.8C11—C16—H16119.6
C1—C2—H2B111.8C26—C21—C22119.26 (12)
C3—C2—H2B111.8C26—C21—C3121.01 (11)
H2A—C2—H2B109.5C22—C21—C3119.73 (12)
O1—C3—C21108.85 (10)C21—C22—C23120.04 (13)
O1—C3—C2103.42 (10)C21—C22—H22120.0
C21—C3—C2117.74 (11)C23—C22—H22120.0
O1—C3—H3108.8C24—C23—C22120.07 (13)
C21—C3—H3108.8C24—C23—H23120.0
C2—C3—H3108.8C22—C23—H23120.0
C12—C11—C16118.86 (11)C23—C24—C25119.78 (14)
C12—C11—C1120.90 (11)C23—C24—H24120.1
C16—C11—C1120.22 (11)C25—C24—H24120.1
C13—C12—C11120.73 (12)C26—C25—C24120.30 (14)
C13—C12—H12119.6C26—C25—H25119.8
C11—C12—H12119.6C24—C25—H25119.8
C14—C13—C12118.98 (12)C25—C26—C21120.55 (13)
C14—C13—H13120.5C25—C26—H26119.7
C12—C13—H13120.5C21—C26—H26119.7
C13—C14—C15121.58 (12)
C3—O1—N1—C113.27 (15)C13—C14—C15—C160.6 (2)
O1—N1—C1—C11179.87 (10)Cl1—C14—C15—C16179.98 (10)
O1—N1—C1—C22.47 (16)C14—C15—C16—C110.26 (19)
N1—C1—C2—C315.95 (14)C12—C11—C16—C150.04 (18)
C11—C1—C2—C3166.57 (11)C1—C11—C16—C15178.79 (11)
N1—O1—C3—C21148.44 (11)O1—C3—C21—C2644.82 (16)
N1—O1—C3—C222.50 (13)C2—C3—C21—C2672.34 (16)
C1—C2—C3—O121.97 (12)O1—C3—C21—C22134.27 (12)
C1—C2—C3—C21142.02 (11)C2—C3—C21—C22108.56 (14)
N1—C1—C11—C12179.87 (12)C26—C21—C22—C230.8 (2)
C2—C1—C11—C122.81 (18)C3—C21—C22—C23179.87 (12)
N1—C1—C11—C161.15 (18)C21—C22—C23—C241.0 (2)
C2—C1—C11—C16178.47 (12)C22—C23—C24—C250.7 (2)
C16—C11—C12—C130.01 (18)C23—C24—C25—C260.1 (2)
C1—C11—C12—C13178.73 (11)C24—C25—C26—C210.1 (2)
C11—C12—C13—C140.36 (19)C22—C21—C26—C250.2 (2)
C12—C13—C14—C150.7 (2)C3—C21—C26—C25179.31 (13)
C12—C13—C14—Cl1179.94 (10)
Hydrogen-bond geometry (Å, º) top
Cg is the centroid of the C11–C16 ring.
D—H···AD—HH···AD···AD—H···A
C12—H12···N1i0.952.743.657 (2)163
C12—H12···O1i0.952.653.390 (2)135
C2—H2B···O1ii0.992.673.466 (2)138
C26—H26···O1ii0.952.703.431 (2)134
C22—H22···Cgiii0.952.813.721 (3)162
Symmetry codes: (i) x+1/2, y+1/2, z+1/2; (ii) x, y, z1/2; (iii) x+1/2, y+1/2, z+1.

Experimental details

Crystal data
Chemical formulaC15H12ClNO
Mr257.71
Crystal system, space groupMonoclinic, C2/c
Temperature (K)200
a, b, c (Å)29.797 (5), 10.717 (5), 8.086 (5)
β (°) 103.088 (5)
V3)2515 (2)
Z8
Radiation typeMo Kα
µ (mm1)0.29
Crystal size (mm)0.58 × 0.42 × 0.21
Data collection
DiffractometerBruker APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2008)
Tmin, Tmax0.850, 0.943
No. of measured, independent and
observed [I > 2σ(I)] reflections
11843, 3132, 2637
Rint0.014
(sin θ/λ)max1)0.667
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.037, 0.103, 1.03
No. of reflections3132
No. of parameters163
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.31, 0.23

Computer programs: APEX2 (Bruker, 2010), SAINT (Bruker, 2010), SHELXS97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2008), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
Cg is the centroid of the C11–C16 ring.
D—H···AD—HH···AD···AD—H···A
C12—H12···N1i0.952.743.657 (2)163
C12—H12···O1i0.952.653.390 (2)135
C2—H2B···O1ii0.992.673.466 (2)138
C26—H26···O1ii0.952.703.431 (2)134
C22—H22···Cgiii0.952.813.721 (3)162
Symmetry codes: (i) x+1/2, y+1/2, z+1/2; (ii) x, y, z1/2; (iii) x+1/2, y+1/2, z+1.
 

Acknowledgements

AMI is thankful to the Department of Atomic Energy, Board for Research in Nuclear Sciences, Government of India, for the Young Scientist award.

References

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