organic compounds
6-Chloro-2H-1,4-benzoxazin-3(4H)-one
aSchool of Chemistry and Chemical Engineering, Xuzhou Institute of Technology, Xuzhou, Jiangsu 221006, People's Republic of China, and bSchool of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People's Republic of China
*Correspondence e-mail: yshxl@yahoo.com.cn
In the title compound, C8H6ClNO2, the conformation of the six-membered heterocyclic ring is close to screw boat and the molecules are linked via intermolecular N—H⋯O hydrogen bonds along the b axis.
Related literature
For biological activities of 1,4-benzoxazin-3(4H)-one derivatives, see: Huang et al. (2005); Macchiarulo et al. (2002). For a related structure, see: Pang et al. (2006).
Experimental
Crystal data
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Data collection: SMART (Bruker 2002); cell SAINT (Bruker 2002); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick 2008); software used to prepare material for publication: SHELXL97.
Supporting information
10.1107/S1600536808035599/wn2285sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536808035599/wn2285Isup2.hkl
To a 25 ml round-bottomed flask equipped with a reflux condenser were added 2-chloro-N-(5-chloro-2-hydroxyphenyl)acetamide (2.19 g, 10 mmol), potassium carbonate (2.76 g, 20 mmol) and anhydrous DMF (20 ml). The resulting mixture was heated under reflux for 90 min. After this time, the reaction mixture was poured into 80 g of water, and stirred for 15 min. The mixture was extracted with ethyl acetate (2 x 20 ml). The ethyl acetate extract was washed with saturated brine (10 ml). After drying over Na2SO4, the solvent was removed under vacuum and a colourless solid was obtained in 80% yield (1.46 g). Suitable crystals were grown by evaporation of a CH2Cl2 solution at room temperature for 4 d.
All H atoms were positioned geometrically (N - H = 0.86 Å, aromatic C - H = 0.93 Å, methylene C - H = 0.97 Å) and refined using a riding model; Uiso(H) = 1.2 Ueq(C, N).
Data collection: SMART (Bruker 2002); cell
SAINT (Bruker 2002); data reduction: SAINT (Bruker 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).Fig. 1. The molecular structure of the title compound, with displacement ellipsoids drawn at the 50% probability level. H atoms are shown as spheres of arbitrary radius. |
C8H6ClNO2 | Dx = 1.641 Mg m−3 |
Mr = 183.59 | Mo Kα radiation, λ = 0.71073 Å |
Orthorhombic, P212121 | Cell parameters from 1287 reflections |
a = 4.5359 (6) Å | θ = 3.3–24.4° |
b = 7.700 (1) Å | µ = 0.46 mm−1 |
c = 21.281 (3) Å | T = 273 K |
V = 743.28 (17) Å3 | Plate, colourless |
Z = 4 | 0.12 × 0.10 × 0.06 mm |
F(000) = 376 |
Bruker SMART CCD area-detector diffractometer | 1314 independent reflections |
Radiation source: fine-focus sealed tube | 1143 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.047 |
ϕ and ω scans | θmax = 25.0°, θmin = 1.9° |
Absorption correction: multi-scan (SADABS; Bruker, 2002) | h = −5→4 |
Tmin = 0.878, Tmax = 0.973 | k = −8→9 |
3857 measured reflections | l = −25→23 |
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)] = 0.038 | H-atom parameters constrained |
wR(F2) = 0.088 | w = 1/[σ2(Fo2) + (0.0401P)2] where P = (Fo2 + 2Fc2)/3 |
S = 1.07 | (Δ/σ)max < 0.001 |
1314 reflections | Δρmax = 0.16 e Å−3 |
109 parameters | Δρmin = −0.21 e Å−3 |
0 restraints | Absolute structure: Flack (1983), 500 Friedel pairs |
Primary atom site location: structure-invariant direct methods | Absolute structure parameter: 0.06 (11) |
C8H6ClNO2 | V = 743.28 (17) Å3 |
Mr = 183.59 | Z = 4 |
Orthorhombic, P212121 | Mo Kα radiation |
a = 4.5359 (6) Å | µ = 0.46 mm−1 |
b = 7.700 (1) Å | T = 273 K |
c = 21.281 (3) Å | 0.12 × 0.10 × 0.06 mm |
Bruker SMART CCD area-detector diffractometer | 1314 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2002) | 1143 reflections with I > 2σ(I) |
Tmin = 0.878, Tmax = 0.973 | Rint = 0.047 |
3857 measured reflections |
R[F2 > 2σ(F2)] = 0.038 | H-atom parameters constrained |
wR(F2) = 0.088 | Δρmax = 0.16 e Å−3 |
S = 1.07 | Δρmin = −0.21 e Å−3 |
1314 reflections | Absolute structure: Flack (1983), 500 Friedel pairs |
109 parameters | Absolute structure parameter: 0.06 (11) |
0 restraints |
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 | ||
Cl1 | 0.59509 (18) | 0.16633 (10) | 0.92672 (4) | 0.0538 (3) | |
O1 | 1.5486 (5) | 0.7552 (2) | 0.74891 (10) | 0.0488 (6) | |
O2 | 1.1177 (4) | 0.8424 (2) | 0.88354 (9) | 0.0466 (6) | |
N1 | 1.2830 (5) | 0.5732 (3) | 0.80882 (10) | 0.0347 (6) | |
H1 | 1.3651 | 0.4842 | 0.7918 | 0.042* | |
C1 | 1.3640 (6) | 0.7302 (3) | 0.79030 (14) | 0.0350 (7) | |
C2 | 1.2111 (7) | 0.8777 (3) | 0.82142 (15) | 0.0448 (8) | |
H2A | 1.3430 | 0.9768 | 0.8222 | 0.054* | |
H2B | 1.0404 | 0.9094 | 0.7965 | 0.054* | |
C3 | 0.9870 (6) | 0.6859 (3) | 0.89160 (13) | 0.0346 (7) | |
C4 | 1.0683 (6) | 0.5467 (3) | 0.85521 (12) | 0.0295 (6) | |
C5 | 0.9496 (6) | 0.3866 (3) | 0.86535 (13) | 0.0339 (6) | |
H5 | 1.0043 | 0.2924 | 0.8406 | 0.041* | |
C6 | 0.7466 (6) | 0.3675 (3) | 0.91299 (13) | 0.0369 (7) | |
C7 | 0.6661 (6) | 0.5045 (4) | 0.94990 (13) | 0.0408 (7) | |
H7 | 0.5317 | 0.4889 | 0.9824 | 0.049* | |
C8 | 0.7839 (6) | 0.6642 (4) | 0.93876 (13) | 0.0402 (7) | |
H8 | 0.7267 | 0.7586 | 0.9631 | 0.048* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cl1 | 0.0588 (5) | 0.0489 (4) | 0.0537 (5) | −0.0086 (4) | 0.0042 (4) | 0.0129 (4) |
O1 | 0.0582 (14) | 0.0464 (11) | 0.0420 (13) | −0.0049 (10) | 0.0170 (12) | 0.0038 (9) |
O2 | 0.0600 (14) | 0.0389 (10) | 0.0410 (13) | −0.0064 (12) | 0.0119 (11) | −0.0098 (9) |
N1 | 0.0375 (13) | 0.0348 (12) | 0.0319 (14) | 0.0014 (11) | 0.0068 (11) | −0.0017 (10) |
C1 | 0.0401 (17) | 0.0378 (14) | 0.0272 (16) | −0.0022 (13) | −0.0029 (14) | −0.0005 (12) |
C2 | 0.0532 (19) | 0.0390 (15) | 0.0423 (19) | −0.0032 (14) | 0.0061 (16) | 0.0019 (14) |
C3 | 0.0362 (16) | 0.0372 (14) | 0.0305 (16) | −0.0012 (13) | −0.0001 (12) | −0.0028 (12) |
C4 | 0.0291 (14) | 0.0372 (14) | 0.0221 (14) | 0.0016 (13) | 0.0002 (13) | −0.0008 (11) |
C5 | 0.0370 (15) | 0.0365 (14) | 0.0282 (15) | 0.0021 (13) | −0.0049 (13) | −0.0006 (11) |
C6 | 0.0357 (15) | 0.0424 (15) | 0.0327 (17) | −0.0011 (13) | −0.0026 (13) | 0.0083 (13) |
C7 | 0.0392 (18) | 0.0534 (17) | 0.0297 (17) | −0.0007 (15) | 0.0057 (13) | 0.0011 (15) |
C8 | 0.0425 (16) | 0.0464 (15) | 0.0315 (17) | 0.0058 (16) | 0.0041 (13) | −0.0052 (14) |
Cl1—C6 | 1.720 (3) | C3—C8 | 1.373 (4) |
O1—C1 | 1.231 (3) | C3—C4 | 1.373 (4) |
O2—C3 | 1.354 (3) | C4—C5 | 1.362 (4) |
O2—C2 | 1.414 (4) | C5—C6 | 1.377 (4) |
N1—C1 | 1.324 (3) | C5—H5 | 0.9300 |
N1—C4 | 1.402 (3) | C6—C7 | 1.365 (4) |
N1—H1 | 0.8600 | C7—C8 | 1.362 (4) |
C1—C2 | 1.486 (4) | C7—H7 | 0.9300 |
C2—H2A | 0.9700 | C8—H8 | 0.9300 |
C2—H2B | 0.9700 | ||
C3—O2—C2 | 114.9 (2) | C5—C4—C3 | 120.7 (3) |
C1—N1—C4 | 122.4 (2) | C5—C4—N1 | 121.2 (2) |
C1—N1—H1 | 118.8 | C3—C4—N1 | 118.0 (2) |
C4—N1—H1 | 118.8 | C4—C5—C6 | 118.5 (3) |
O1—C1—N1 | 123.0 (3) | C4—C5—H5 | 120.7 |
O1—C1—C2 | 121.1 (2) | C6—C5—H5 | 120.7 |
N1—C1—C2 | 115.8 (3) | C7—C6—C5 | 121.3 (3) |
O2—C2—C1 | 114.2 (2) | C7—C6—Cl1 | 119.4 (2) |
O2—C2—H2A | 108.7 | C5—C6—Cl1 | 119.2 (2) |
C1—C2—H2A | 108.7 | C8—C7—C6 | 119.5 (3) |
O2—C2—H2B | 108.7 | C8—C7—H7 | 120.2 |
C1—C2—H2B | 108.7 | C6—C7—H7 | 120.2 |
H2A—C2—H2B | 107.6 | C7—C8—C3 | 120.1 (3) |
O2—C3—C8 | 119.7 (2) | C7—C8—H8 | 120.0 |
O2—C3—C4 | 120.4 (2) | C3—C8—H8 | 120.0 |
C8—C3—C4 | 119.8 (3) | ||
C4—N1—C1—O1 | −178.8 (2) | C1—N1—C4—C5 | 167.7 (3) |
C4—N1—C1—C2 | −0.5 (4) | C1—N1—C4—C3 | −14.2 (4) |
C3—O2—C2—C1 | −44.4 (3) | C3—C4—C5—C6 | −0.1 (4) |
O1—C1—C2—O2 | −152.3 (3) | N1—C4—C5—C6 | 177.9 (2) |
N1—C1—C2—O2 | 29.4 (4) | C4—C5—C6—C7 | −0.5 (4) |
C2—O2—C3—C8 | −152.6 (3) | C4—C5—C6—Cl1 | −179.8 (2) |
C2—O2—C3—C4 | 31.1 (3) | C5—C6—C7—C8 | 1.3 (4) |
O2—C3—C4—C5 | 176.3 (3) | Cl1—C6—C7—C8 | −179.4 (2) |
C8—C3—C4—C5 | 0.0 (4) | C6—C7—C8—C3 | −1.4 (4) |
O2—C3—C4—N1 | −1.7 (4) | O2—C3—C8—C7 | −175.6 (2) |
C8—C3—C4—N1 | −178.1 (2) | C4—C3—C8—C7 | 0.8 (4) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···O1i | 0.86 | 2.00 | 2.844 (3) | 166 |
Symmetry code: (i) −x+3, y−1/2, −z+3/2. |
Experimental details
Crystal data | |
Chemical formula | C8H6ClNO2 |
Mr | 183.59 |
Crystal system, space group | Orthorhombic, P212121 |
Temperature (K) | 273 |
a, b, c (Å) | 4.5359 (6), 7.700 (1), 21.281 (3) |
V (Å3) | 743.28 (17) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.46 |
Crystal size (mm) | 0.12 × 0.10 × 0.06 |
Data collection | |
Diffractometer | Bruker SMART CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2002) |
Tmin, Tmax | 0.878, 0.973 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 3857, 1314, 1143 |
Rint | 0.047 |
(sin θ/λ)max (Å−1) | 0.595 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.038, 0.088, 1.07 |
No. of reflections | 1314 |
No. of parameters | 109 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.16, −0.21 |
Absolute structure | Flack (1983), 500 Friedel pairs |
Absolute structure parameter | 0.06 (11) |
Computer programs: SMART (Bruker 2002), SAINT (Bruker 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XP in SHELXTL (Sheldrick 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···O1i | 0.86 | 2.00 | 2.844 (3) | 166 |
Symmetry code: (i) −x+3, y−1/2, −z+3/2. |
References
Bruker (2002). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Flack, H. D. (1983). Acta Cryst. A39, 876–881. CrossRef CAS Web of Science IUCr Journals Google Scholar
Huang, M. Z., Huang, K. L., Ren, Y. G., Lei, M. X., Huang, L., Hou, Z. K., Liu, A. P. & Ou, X. M. (2005). J. Agric. Food Chem. 53, 7908–7914. Web of Science CrossRef PubMed CAS Google Scholar
Macchiarulo, A., Costantino, G., Fringuelli, D., Vecchiarelli, A., Schiaffella, F. & Fringueui, R. (2002). Bioorg. Med. Chem. 10, 3415–3423. Web of Science CrossRef PubMed CAS Google Scholar
Pang, H.-L., Yang, H., Yin, D.-L. & Mao, C.-H. (2006). Acta Cryst. E62, o5165–o5166. Web of Science CSD CrossRef IUCr Journals Google Scholar
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Benzo[1,4]oxazin-3(4H)-one derivatives are one of the important classes of heterocyclic compounds and have been shown to exhibit a wide range of biological activities such as herbicidal (Huang et al., 2005) and antifungal (Macchiarulo et al., 2002). We report here the crystal structure of 6-chloro-2H-benzo[b][1,4]oxazin-3(4H)-one.
The molecular structure is illustrated in Fig. 1. The conformation of the six-membered heterocyclic ring is close to screw boat, with atoms C1 and C2 out of the plane of the remaining four atoms by 0.301 (5) and 0.635 (5) Å, respectively. In a related compound containing the benzo[1,4]oxazin-3(4H)-one system (Pang et al., 2006), the heterocyclic ring also adopts a screw boat conformation. The molecules are connected via N - H ··· O hydrogen bonding into chains along the b axis.