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Acta Crystallogr Sect E Struct Rep Online. 2009 August 1; 65(Pt 8): o1857.
Published online 2009 July 15. doi:  10.1107/S1600536809025999
PMCID: PMC2977315

Ortho­rhom­bic modification of (E)-4-benzyl­idene-2-phenyl-1,3-oxazol-5(4H)-one: whole mol­ecule disorder

Abstract

The title mol­ecule, C16H11NO2, is disordered about a pseudo-twofold rotation axis that approximately bis­ects the mol­ecule along the C=O double bond. The two overlapping components are planar [r.m.s. deviation = 0.10 Å in the major 0.537 (4) component and 0.07 Å in the minor component]. The two components are aligned at 1.8 (3)°.

Related literature

For the monoclinic modification, see: Busetti et al. (1993 [triangle]).

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Object name is e-65-o1857-scheme1.jpg

Experimental

Crystal data

  • C16H11NO2
  • M r = 249.26
  • Orthorhombic, An external file that holds a picture, illustration, etc.
Object name is e-65-o1857-efi1.jpg
  • a = 3.9320 (1) Å
  • b = 14.7692 (5) Å
  • c = 20.6690 (6) Å
  • V = 1200.30 (6) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.09 mm−1
  • T = 140 K
  • 0.45 × 0.10 × 0.05 mm

Data collection

  • Bruker SMART APEX diffractometer
  • Absorption correction: none
  • 8204 measured reflections
  • 1640 independent reflections
  • 1312 reflections with I > 2σ(I)
  • R int = 0.036

Refinement

  • R[F 2 > 2σ(F 2)] = 0.044
  • wR(F 2) = 0.125
  • S = 1.03
  • 1640 reflections
  • 182 parameters
  • H-atom parameters constrained
  • Δρmax = 0.29 e Å−3
  • Δρmin = −0.17 e Å−3

Data collection: APEX2 (Bruker, 2008 [triangle]); cell refinement: SAINT (Bruker, 2008 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: X-SEED (Barbour, 2001 [triangle]); software used to prepare material for publication: publCIF (Westrip, 2009 [triangle]).

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809025999/tk2490sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809025999/tk2490Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

I thank Professor Abdullah Mohamed Asiri of King Abdul Aziz University for providing the crystal for this study.

supplementary crystallographic information

Experimental

Anhydrous sodium acetate (0.26 g, 0.0036 mol) was added to solution of benzaldehyde (1 g, 0.0036 mol) and hippuric acid (0.77 g, 0.0043 mol) in acetic anhydride (0.27 ml, 0028 mol). The mixture was heated to 353 K for 2 h. Ethanol (10 ml) was added to the cool mixture to precipitate a yellow solid. This was collected and recrystallized from aqueous acetone to give yellow crystals in 60% yield; m.p. 443 K.

Refinement

The molecule is disordered about a false 2-fold rotation axis that approximately bisects the molecule along the carbon-oxygen double bond. The aromatic rings were refined as rigid hexagons of 1.39 Å sides. The displacement factors of the primed atoms were restrained to those of the umprimed ones.

Carbon-bound H-atoms were placed in calculated positions (C—H 0.95 Å) and were included in the refinement in the riding model approximation with U(H) fixed at 1.2Ueq(C).

In the absence of significant anomalous scattering effects, 1076 Friedel pairs were averaged in the final refinement.

Figures

Fig. 1.
Thermal ellipsoid plot (Barbour, 2001) of the major, 0.537 (4), component of disordered C16H11NO2, shown at the 70% probability level. Hydrogen atoms are drawn as spheres of arbitrary radius.
Fig. 2.
Detail showing the disorder. The minor disorder component is indicated with primed atoms and dotted bonds.

Crystal data

C16H11NO2F(000) = 520
Mr = 249.26Dx = 1.379 Mg m3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 1737 reflections
a = 3.9320 (1) Åθ = 2.5–25.8°
b = 14.7692 (5) ŵ = 0.09 mm1
c = 20.6690 (6) ÅT = 140 K
V = 1200.30 (6) Å3Prism, yellow
Z = 40.45 × 0.10 × 0.05 mm

Data collection

Bruker SMART APEX diffractometer1312 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.036
graphiteθmax = 27.5°, θmin = 1.7°
ω scansh = −5→4
8204 measured reflectionsk = −19→19
1640 independent reflectionsl = −25→26

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.044H-atom parameters constrained
wR(F2) = 0.125w = 1/[σ2(Fo2) + (0.0752P)2 + 0.1226P] where P = (Fo2 + 2Fc2)/3
S = 1.03(Δ/σ)max = 0.001
1640 reflectionsΔρmax = 0.29 e Å3
182 parametersΔρmin = −0.17 e Å3
0 restraintsAbsolute structure: nd
Primary atom site location: structure-invariant direct methods

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2)

xyzUiso*/UeqOcc. (<1)
O1−0.109 (5)0.373 (3)0.2237 (16)0.031 (2)0.537 (4)
O20.1605 (8)0.2739 (2)0.28782 (13)0.0282 (5)0.537 (4)
N10.432 (3)0.3613 (3)0.3629 (6)0.0229 (10)0.537 (4)
C10.4568 (11)0.19591 (18)0.37320 (16)0.0256 (7)0.537 (4)
C20.3888 (11)0.1143 (2)0.34231 (13)0.0280 (10)0.537 (4)
H20.27150.11390.30210.034*0.537 (4)
C30.4924 (12)0.03323 (18)0.37021 (15)0.0304 (9)0.537 (4)
H30.4460−0.02250.34910.037*0.537 (4)
C40.6641 (13)0.03378 (19)0.42900 (16)0.0236 (10)0.537 (4)
H40.7349−0.02160.44810.028*0.537 (4)
C50.7321 (13)0.1154 (2)0.45989 (15)0.0285 (11)0.537 (4)
H50.84940.11580.50010.034*0.537 (4)
C60.6284 (12)0.19646 (18)0.43199 (17)0.0246 (9)0.537 (4)
H60.67490.25220.45310.029*0.537 (4)
C70.4345 (10)0.5780 (2)0.35423 (15)0.0225 (7)0.537 (4)
C80.4110 (11)0.6682 (2)0.33534 (13)0.0264 (9)0.537 (4)
H80.30290.68350.29570.032*0.537 (4)
C90.5458 (14)0.73583 (17)0.37442 (17)0.0291 (9)0.537 (4)
H90.52970.79740.36150.035*0.537 (4)
C100.7040 (15)0.7134 (2)0.43239 (17)0.0333 (13)0.537 (4)
H100.79600.75970.45910.040*0.537 (4)
C110.7274 (14)0.6233 (3)0.45127 (17)0.0255 (10)0.537 (4)
H110.83560.60800.49090.031*0.537 (4)
C120.5927 (12)0.55561 (18)0.41219 (18)0.0270 (10)0.537 (4)
H120.60880.49400.42510.032*0.537 (4)
C130.081 (5)0.3626 (7)0.2675 (10)0.0237 (18)0.537 (4)
C140.2749 (12)0.4188 (3)0.31640 (18)0.0247 (5)0.537 (4)
C150.2789 (12)0.5102 (3)0.31202 (19)0.0255 (6)0.537 (4)
H150.16160.53410.27570.031*0.537 (4)
C160.3550 (11)0.2805 (3)0.34289 (17)0.0234 (6)0.537 (4)
O1'−0.037 (6)0.376 (3)0.2199 (18)0.031 (2)0.463
O2'0.1691 (10)0.4755 (2)0.28423 (15)0.0282 (5)0.463
N1'0.421 (4)0.3896 (4)0.3594 (7)0.0229 (10)0.463
C1'0.4779 (13)0.5543 (2)0.36785 (19)0.0256 (7)0.463
C2'0.4019 (13)0.6351 (3)0.33667 (16)0.0280 (10)0.463
H2'0.27890.63450.29710.034*0.463 (4)
C3'0.5060 (16)0.7170 (2)0.3634 (2)0.0304 (9)0.463
H3'0.45400.77230.34200.037*0.463 (4)
C4'0.6860 (18)0.7179 (2)0.4212 (2)0.0236 (10)0.463
H4'0.75710.77380.43950.028*0.463 (4)
C5'0.7620 (17)0.6370 (3)0.4524 (2)0.0285 (11)0.463
H5'0.88500.63770.49200.034*0.463 (4)
C6'0.6580 (15)0.5552 (2)0.4257 (2)0.0246 (9)0.463
H6'0.70990.49990.44700.029*0.463 (4)
C7'0.4147 (13)0.1731 (2)0.35940 (18)0.0225 (7)0.463
C8'0.3876 (14)0.0824 (3)0.34221 (15)0.0264 (9)0.463
H8'0.28390.06600.30240.032*0.463 (4)
C9'0.5123 (17)0.0157 (2)0.38330 (19)0.0291 (9)0.463
H9'0.4938−0.04630.37160.035*0.463 (4)
C10'0.6641 (17)0.0397 (3)0.44157 (19)0.0333 (13)0.463
H10B0.7493−0.00590.46960.040*0.463 (4)
C11'0.6911 (16)0.1304 (3)0.45875 (19)0.0255 (10)0.463
H11B0.79480.14680.49860.031*0.463 (4)
C12'0.5664 (15)0.1971 (2)0.4177 (2)0.0270 (10)0.463
H12B0.58490.25910.42940.032*0.463 (4)
C13'0.112 (6)0.3856 (9)0.2697 (12)0.0237 (18)0.463
C14'0.2695 (14)0.3313 (3)0.3171 (2)0.0247 (5)0.463
C15'0.2625 (14)0.2393 (3)0.3151 (2)0.0255 (6)0.463
H15B0.14080.21410.27970.031*0.463 (4)
C16'0.3654 (13)0.4697 (3)0.3398 (2)0.0234 (6)0.463

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.017 (7)0.048 (3)0.029 (3)−0.004 (7)−0.006 (5)0.000 (2)
O20.0293 (11)0.0299 (10)0.0255 (10)−0.0017 (12)−0.0039 (9)−0.0011 (10)
N10.0248 (13)0.021 (3)0.0229 (14)0.007 (4)0.0002 (11)0.006 (3)
C10.0230 (17)0.0248 (14)0.0290 (17)0.0008 (17)0.0078 (14)−0.0006 (12)
C20.0316 (18)0.027 (3)0.0250 (15)−0.001 (3)0.0010 (12)−0.0002 (14)
C30.032 (2)0.0311 (17)0.0284 (16)0.001 (2)0.0008 (15)0.0019 (14)
C40.027 (3)0.0140 (17)0.0296 (17)−0.004 (2)0.0084 (16)0.0016 (13)
C50.030 (2)0.0227 (18)0.033 (3)0.0016 (19)0.0003 (19)−0.0007 (14)
C60.0154 (19)0.0302 (19)0.0281 (17)0.0010 (17)−0.0032 (15)−0.0020 (14)
C70.0216 (16)0.0235 (15)0.0224 (13)0.0007 (17)0.0047 (12)−0.0011 (12)
C80.0321 (19)0.022 (2)0.0253 (16)0.000 (2)0.0020 (14)0.0007 (14)
C90.035 (2)0.0214 (13)0.0310 (17)−0.0025 (18)0.0019 (16)0.0021 (12)
C100.030 (3)0.042 (3)0.0281 (18)0.007 (3)−0.0007 (18)−0.0018 (17)
C110.0223 (19)0.0247 (17)0.030 (2)0.000 (2)−0.0010 (17)0.0008 (15)
C120.027 (2)0.0239 (18)0.030 (2)0.0014 (18)−0.0006 (17)−0.0007 (14)
C130.022 (4)0.024 (6)0.0252 (15)−0.009 (5)−0.002 (2)−0.007 (5)
C140.0217 (13)0.0305 (13)0.0217 (12)0.0035 (16)0.0004 (11)−0.0006 (14)
C150.0237 (15)0.0306 (14)0.0221 (13)0.0036 (16)0.0002 (12)0.0011 (15)
C160.0222 (14)0.0279 (14)0.0202 (12)−0.0010 (17)0.0009 (11)−0.0006 (15)
O1'0.017 (7)0.048 (3)0.029 (3)−0.004 (7)−0.006 (5)0.000 (2)
O2'0.0293 (11)0.0299 (10)0.0255 (10)−0.0017 (12)−0.0039 (9)−0.0011 (10)
N1'0.0248 (13)0.021 (3)0.0229 (14)0.007 (4)0.0002 (11)0.006 (3)
C1'0.0230 (17)0.0248 (14)0.0290 (17)0.0008 (17)0.0078 (14)−0.0006 (12)
C2'0.0316 (18)0.027 (3)0.0250 (15)−0.001 (3)0.0010 (12)−0.0002 (14)
C3'0.032 (2)0.0311 (17)0.0284 (16)0.001 (2)0.0008 (15)0.0019 (14)
C4'0.027 (3)0.0140 (17)0.0296 (17)−0.004 (2)0.0084 (16)0.0016 (13)
C5'0.030 (2)0.0227 (18)0.033 (3)0.0016 (19)0.0003 (19)−0.0007 (14)
C6'0.0154 (19)0.0302 (19)0.0281 (17)0.0010 (17)−0.0032 (15)−0.0020 (14)
C7'0.0216 (16)0.0235 (15)0.0224 (13)0.0007 (17)0.0047 (12)−0.0011 (12)
C8'0.0321 (19)0.022 (2)0.0253 (16)0.000 (2)0.0020 (14)0.0007 (14)
C9'0.035 (2)0.0214 (13)0.0310 (17)−0.0025 (18)0.0019 (16)0.0021 (12)
C10'0.030 (3)0.042 (3)0.0281 (18)0.007 (3)−0.0007 (18)−0.0018 (17)
C11'0.0223 (19)0.0247 (17)0.030 (2)0.000 (2)−0.0010 (17)0.0008 (15)
C12'0.027 (2)0.0239 (18)0.030 (2)0.0014 (18)−0.0006 (17)−0.0007 (14)
C13'0.022 (4)0.024 (6)0.0252 (15)−0.009 (5)−0.002 (2)−0.007 (5)
C14'0.0217 (13)0.0305 (13)0.0217 (12)0.0035 (16)0.0004 (11)−0.0006 (14)
C15'0.0237 (15)0.0306 (14)0.0221 (13)0.0036 (16)0.0002 (12)0.0011 (15)
C16'0.0222 (14)0.0279 (14)0.0202 (12)−0.0010 (17)0.0009 (11)−0.0006 (15)

Geometric parameters (Å, °)

O1—C131.18 (4)O1'—C13'1.19 (5)
O2—C161.375 (5)O2'—C13'1.378 (13)
O2—C131.412 (15)O2'—C16'1.386 (6)
N1—C161.300 (9)N1'—C16'1.270 (8)
N1—C141.424 (9)N1'—C14'1.365 (14)
C1—C21.3900C1'—C2'1.3900
C1—C61.3900C1'—C6'1.3900
C1—C161.453 (4)C1'—C16'1.446 (6)
C2—C31.3900C2'—C3'1.3900
C2—H20.9500C2'—H2'0.9500
C3—C41.3900C3'—C4'1.3900
C3—H30.9500C3'—H3'0.9500
C4—C51.3900C4'—C5'1.3900
C4—H40.9500C4'—H4'0.9500
C5—C61.3900C5'—C6'1.3900
C5—H50.9500C5'—H5'0.9500
C6—H60.9500C6'—H6'0.9500
C7—C81.3900C7'—C8'1.3900
C7—C121.3900C7'—C12'1.3900
C7—C151.463 (5)C7'—C15'1.467 (6)
C8—C91.3900C8'—C9'1.3900
C8—H80.9500C8'—H8'0.9500
C9—C101.3900C9'—C10'1.3900
C9—H90.9500C9'—H9'0.9500
C10—C111.3900C10'—C11'1.3900
C10—H100.9500C10'—H10B0.9500
C11—C121.3900C11'—C12'1.3900
C11—H110.9500C11'—H11B0.9500
C12—H120.9500C12'—H12B0.9500
C13—C141.515 (15)C13'—C14'1.41 (2)
C14—C151.352 (5)C14'—C15'1.359 (6)
C15—H150.9500C15'—H15B0.9500
C16—O2—C13107.7 (8)C13'—O2'—C16'102.2 (11)
C16—N1—C14103.4 (8)C16'—N1'—C14'107.9 (10)
C2—C1—C6120.0C2'—C1'—C6'120.0
C2—C1—C16119.6 (3)C2'—C1'—C16'119.4 (3)
C6—C1—C16120.4 (3)C6'—C1'—C16'120.6 (3)
C3—C2—C1120.0C3'—C2'—C1'120.0
C3—C2—H2120.0C3'—C2'—H2'120.0
C1—C2—H2120.0C1'—C2'—H2'120.0
C2—C3—C4120.0C2'—C3'—C4'120.0
C2—C3—H3120.0C2'—C3'—H3'120.0
C4—C3—H3120.0C4'—C3'—H3'120.0
C5—C4—C3120.0C5'—C4'—C3'120.0
C5—C4—H4120.0C5'—C4'—H4'120.0
C3—C4—H4120.0C3'—C4'—H4'120.0
C6—C5—C4120.0C4'—C5'—C6'120.0
C6—C5—H5120.0C4'—C5'—H5'120.0
C4—C5—H5120.0C6'—C5'—H5'120.0
C5—C6—C1120.0C5'—C6'—C1'120.0
C5—C6—H6120.0C5'—C6'—H6'120.0
C1—C6—H6120.0C1'—C6'—H6'120.0
C8—C7—C12120.0C8'—C7'—C12'120.0
C8—C7—C15117.4 (3)C8'—C7'—C15'116.8 (4)
C12—C7—C15122.5 (3)C12'—C7'—C15'123.1 (4)
C9—C8—C7120.0C7'—C8'—C9'120.0
C9—C8—H8120.0C7'—C8'—H8'120.0
C7—C8—H8120.0C9'—C8'—H8'120.0
C8—C9—C10120.0C8'—C9'—C10'120.0
C8—C9—H9120.0C8'—C9'—H9'120.0
C10—C9—H9120.0C10'—C9'—H9'120.0
C11—C10—C9120.0C11'—C10'—C9'120.0
C11—C10—H10120.0C11'—C10'—H10B120.0
C9—C10—H10120.0C9'—C10'—H10B120.0
C10—C11—C12120.0C10'—C11'—C12'120.0
C10—C11—H11120.0C10'—C11'—H11B120.0
C12—C11—H11120.0C12'—C11'—H11B120.0
C11—C12—C7120.0C11'—C12'—C7'120.0
C11—C12—H12120.0C11'—C12'—H12B120.0
C7—C12—H12120.0C7'—C12'—H12B120.0
O1—C13—O2119 (2)O1'—C13'—O2'113 (3)
O1—C13—C14140 (2)O1'—C13'—C14'138 (3)
O2—C13—C14101.4 (13)O2'—C13'—C14'109.0 (15)
C15—C14—N1129.4 (5)C15'—C14'—N1'131.3 (6)
C15—C14—C13120.5 (7)C15'—C14'—C13'122.6 (7)
N1—C14—C13110.1 (8)N1'—C14'—C13'106.1 (7)
C14—C15—C7130.4 (4)C14'—C15'—C7'129.7 (5)
C14—C15—H15114.8C14'—C15'—H15B115.2
C7—C15—H15114.8C7'—C15'—H15B115.2
N1—C16—O2117.3 (6)N1'—C16'—O2'114.7 (8)
N1—C16—C1126.0 (6)N1'—C16'—C1'128.5 (8)
O2—C16—C1116.7 (4)O2'—C16'—C1'116.7 (4)
C6—C1—C2—C30.0C6'—C1'—C2'—C3'0.0
C16—C1—C2—C3178.5 (4)C16'—C1'—C2'—C3'179.5 (5)
C1—C2—C3—C40.0C1'—C2'—C3'—C4'0.0
C2—C3—C4—C50.0C2'—C3'—C4'—C5'0.0
C3—C4—C5—C60.0C3'—C4'—C5'—C6'0.0
C4—C5—C6—C10.0C4'—C5'—C6'—C1'0.0
C2—C1—C6—C50.0C2'—C1'—C6'—C5'0.0
C16—C1—C6—C5−178.5 (4)C16'—C1'—C6'—C5'−179.5 (5)
C12—C7—C8—C90.0C12'—C7'—C8'—C9'0.0
C15—C7—C8—C9178.2 (4)C15'—C7'—C8'—C9'−177.1 (5)
C7—C8—C9—C100.0C7'—C8'—C9'—C10'0.0
C8—C9—C10—C110.0C8'—C9'—C10'—C11'0.0
C9—C10—C11—C120.0C9'—C10'—C11'—C12'0.0
C10—C11—C12—C70.0C10'—C11'—C12'—C7'0.0
C8—C7—C12—C110.0C8'—C7'—C12'—C11'0.0
C15—C7—C12—C11−178.1 (4)C15'—C7'—C12'—C11'176.9 (5)
C16—O2—C13—O1−173.9 (18)C16'—O2'—C13'—O1'−175 (2)
C16—O2—C13—C143.3 (13)C16'—O2'—C13'—C14'1.1 (18)
C16—N1—C14—C15−178.0 (5)C16'—N1'—C14'—C15'177.7 (7)
C16—N1—C14—C132.4 (13)C16'—N1'—C14'—C13'−0.4 (16)
O1—C13—C14—C15−7(3)O1'—C13'—C14'—C15'−4(4)
O2—C13—C14—C15176.8 (7)O2'—C13'—C14'—C15'−178.8 (9)
O1—C13—C14—N1173 (3)O1'—C13'—C14'—N1'175 (3)
O2—C13—C14—N1−3.6 (15)O2'—C13'—C14'—N1'−1(2)
N1—C14—C15—C7−2.2 (10)N1'—C14'—C15'—C7'1.2 (13)
C13—C14—C15—C7177.3 (10)C13'—C14'—C15'—C7'179.0 (13)
C8—C7—C15—C14176.7 (4)C8'—C7'—C15'—C14'−175.1 (5)
C12—C7—C15—C14−5.2 (6)C12'—C7'—C15'—C14'7.9 (8)
C14—N1—C16—O2−0.2 (11)C14'—N1'—C16'—O2'1.2 (14)
C14—N1—C16—C1179.5 (5)C14'—N1'—C16'—C1'−179.1 (6)
C13—O2—C16—N1−2.2 (12)C13'—O2'—C16'—N1'−1.4 (15)
C13—O2—C16—C1178.1 (10)C13'—O2'—C16'—C1'178.8 (12)
C2—C1—C16—N1−172.6 (8)C2'—C1'—C16'—N1'176.8 (10)
C6—C1—C16—N15.9 (9)C6'—C1'—C16'—N1'−3.7 (11)
C2—C1—C16—O27.1 (5)C2'—C1'—C16'—O2'−3.5 (6)
C6—C1—C16—O2−174.4 (3)C6'—C1'—C16'—O2'176.0 (4)

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: TK2490).

References

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  • Westrip, S. P. (2009). publCIF In preparation.

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