organic papers
Acta Cryst.(2005). E61, o769–o771 doi:10.1107/S160053680500543X Ivo Vencatoet al. C14H10ClNO
o769
Acta Crystallographica Section E Structure Reports Online
ISSN 1600-5368
3-(4-Chlorophenyl)-2
H
-benz[
b
][1,4]oxazine
Ivo Vencato,a* Pedro H. Ferri,b Lourival C. Faria,bSuzana C. Santosband Carlito Lariuccia
aInstituto de Fı´sica–UFG, Caixa Postal 131,
74001-970 Goiaˆnia, GO, Brazil, andbInstituto
de Quı´mica–UFG, Caixa Postal 131, 74001-970 Goiaˆnia, GO, Brazil
Correspondence e-mail: vencato@if.ufg.br
Key indicators
Single-crystal X-ray study
T= 298 K
Mean(C–C) = 0.003 A˚
Rfactor = 0.043
wRfactor = 0.132
Data-to-parameter ratio = 12.2
For details of how these key indicators were automatically derived from the article, see http://journals.iucr.org/e.
#2005 International Union of Crystallography Printed in Great Britain – all rights reserved
The title compound, C14H10ClNO, is a nitrogen derivative
closely related to natural 30,7-epoxy-8,40-oxyneolignans, which
are of interest because of their cytotoxic activity. Centrosym-metric hydrogen bonding occurs between pairs of molecules.
Comment
Neolignans belong to an important group of bioactive natural products widely distributed in terrestrial plants (Gottlieb & Yoshida, 1990). In particular, neolignans with a 3-aryl-1,4-benzodioxane skeleton constitute the frameworks of a small group, named 30,7-epoxy-8,40-oxyneolignans, whose members
have been isolated from plants of the Lauraceae, Myristica-ceae, andPhytolaccaceaefamilies (Paulino Filho, 1985). Their structural elements seem to occur only rarely in lignins (Hwang & Sakakibara, 1981). In connection with some other natural and synthetic work on biologically active neolignan derivatives (Barataet al., 2000), we became interested in the preparation of C-7 nitrogen analogues of 30,7-epoxy-8,40
-oxy-neolignans, such as compound (II), previously obtained in moderate yields (Shridharet al., 1981; Sabitha & Rao, 1987).
Compounds with the 2H-benz[b][1,4]oxazine system have
been synthesized in an attempt to obtain anti-inflammatory, central muscle relaxant, diuretic, antibacterial, anti-amoebic, antitrichomonal and anthelmintic agents (Shridhar et al., 1986).
The title compound, (II), has not shown in vitro
anti-bacterial activity againstEscherichia coli(Oliveiraet al., 1994), despite the moderate antibacterial activity (Santoset al., 1994) of the starting compound, (I), which has been evaluated using CO2conductimetric determination by flow injection analysis
(Jardimet al., 1990). In this paper, the crystal structure of (II) is described. In (II), the chain of atoms C7/N/C10/C9/O/C8 is analogous to a 30,7-epoxy-8,40-oxyneolignan, and compound
(II) can be considered its nitrogen derivative, according to accepted neolignan nomenclature (Moss, 2000). The present crystal structure will enable conclusions to be drawn about the geometry of this derivative and may contribute to the
standing of the biological differences between the above compounds.
Fig. 1 shows a molecule of (II) with the atomic numbering scheme and Table 1 lists selected bond distances and angles.
The ring O!C9! !C8 shows a screw-boat conformation,
according to the Cremer & Pople (1975) parameters Q =
0.354 (2) A˚ ,= 66.2 (3)and’= 34.3 (4). The aromatic rings
are coplanar within 0.03 A˚ , and the N, O, C7 and C8 atoms are
out of this plane by 0.126 (2), 0.069 (2), 0.099 (2) and
0.453 (3) A˚ , respectively. Steric strain as a result of the C8— H8A Oiinteraction [symmetry code: (i) 1x, 1y, 2z] leads to distortions of the C8 environment, as can be seen in Tables 1 and 2. The average bond angle at C8 is 109.4. A
search of the November 2004 release of the Cambridge Structural Database (Allen, 2002) showed a compound similar to (II), viz. 3-methyl-2-phenyl-2H-benz[1,4]oxazin-2-ol (Santes et al., 1999), with the same 2H-benz[b][1,4]oxazine ring, but with different substituents. No significant differences
were found in the bond distances and angles of the two mol-ecules, except that, in the case of (II), the C7—C8—O angle is 112.6 (2), while in the earlier structure, the corresponding
angle is 110.6, consistent with the distortion observed in our
case. The molecules of (II) are linked into pairs about
crys-tallographic inversion centres through a non-classical
hydrogen-bonded network (Gu et al., 1999); the geometric
parameters are reported in Table 2. Repetition of these pairs of molecules by crystal symmetry results in the formation of columns of molecules, as can be seen in a projection along the monoclinicbaxis (Fig. 2).
Experimental
Compound (II) was obtained in 98% yield from the reduction of 1-(4-chlorophenyl)-2-(2-nitrophenoxy)propan-1-one, (I), using the method described previously by Owsley & Bloomfield (1977). Pris-matic crystals (m.p. 433–434 K) were obtained from a solution in EtOH. FT–IR (Perkin–Elmer, KBr,, cm1): 1610 (C N), 1090 and 1220 (C—O), 880 (C—N); 1H NMR (Varian Gemini, 300 MHz,
CDCl3/TMS,, p.p.m.): 4.98 (s, H8), 6.81 (dd,J= 1.5 and 7.8 Hz, H14),
6.94 (ddd,J= 1.5, 7.5 and 8.4 Hz, H12), 7.06 (ddd,J= 2.4, 7.5 and 7.8 Hz, H13), 7.31 (dd,J= 2.4 and 8.4 Hz, H11), 7.40 (dd,J= 2.4 and 8.4 Hz, H2 and H6), 7.87 (dd,J= 2.4 and 8.4 Hz, H3 and H5);13C
NMR (Varian Gemini, 75 MHz, CDCl3/TMS,, p.p.m.): 133.8 (C4),
129.0 (C3, C5), 127.7 (C2, C6), 137.0 (C1), 157.3 (C7), 62.6 (C8), 146.2 (C9), 133.6 (C10), 127.8 (C11), 122.4 (C12), 128.8 (C13), 115.6 (C14);
EI–MS [Varian MAT-311A, m/z, (relative abundance)]:
253 (100) (M+), 252 (46) (M+1), 182 (8) (M+HCN), 137 (53)
(ArCN+), 111 (8) (Ar+).
Crystal data
C14H10ClNO
Mr= 243.68
Monoclinic,P21=c
a= 13.861 (3) A˚
b= 5.834 (1) A˚
c= 14.903 (3) A˚
= 110.65 (3) V= 1127.7 (4) A˚3
Z= 4
Dx= 1.435 Mg m
3
MoKradiation Cell parameters from 25
reflections
= 9.8–13.8
= 0.32 mm1
T= 298 (2) K Prism, light brown 0.350.350.10 mm
Data collection
Enraf–Nonius CAD-4 diffractometer Non-profiled!/2scans Absorption correction: scan
(Northet al., 1968)
Tmin= 0.901,Tmax= 0.970 2055 measured reflections 1970 independent reflections 1543 reflections withI> 2(I)
Rint= 0.016
max= 25.0
h=16!0
k=6!0
l=16!17 2 standard reflections
frequency: 120 min intensity decay:<1%
Refinement
Refinement onF2
R[F2> 2(F2)] = 0.043
wR(F2) = 0.132
S= 1.05 1970 reflections 161 parameters
H atoms treated by a mixture of independent and constrained refinement
w= 1/[2(F
o2) + (0.0668P)2
+ 0.5604P]
whereP= (Fo2+ 2Fc2)/3
(/)max= 0.004
max= 0.47 e A˚ 3
min=0.27 e A˚ 3
Extinction correction:SHELXL97
Extinction coefficient: 0.017 (3)
organic papers
[image:2.610.43.298.74.213.2] [image:2.610.46.299.279.470.2]o770
Ivo Vencatoet al. C14H10ClNO Acta Cryst.(2005). E61, o769–o771Figure 1
View of (II), with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radii.
Figure 2
Table 1
Selected geometric parameters (A˚ ,).
Cl—C1 1.738 (2)
O—C9 1.373 (3)
O—C8 1.423 (3)
N—C7 1.283 (3)
N—C10 1.413 (3)
C7—C8 1.506 (3)
C8—H8B 1.12 (2)
C8—H8A 0.88 (2)
C9—O—C8 114.05 (17)
C7—N—C10 117.16 (18)
O—C8—C7 112.6 (2)
O—C8—H8B 111.1 (14)
C7—C8—H8B 113.0 (14)
O—C8—H8A 106.6 (18)
C7—C8—H8A 112.1 (18)
H8B—C8—H8A 101 (2)
Table 2
Hydrogen-bonding geometry (A˚ ,).
D—H A D—H H A D A D—H A
C8—H8A Oi
0.88 (2) 2.60 (2) 3.465 (3) 166 (2)
Symmetry code: (i) 1x;1y;2z.
The H atoms on atom C8 were found in a difference Fourier map and their positions were refined with the restraints H H = 1.59 (4) A˚ and C—H = 0.97 (4) A˚, and withUiso(H) = 1.2Ueq(C). These restraints ensure a reasonable geometry for the C8 group, since it has one H atom involved in hydrogen bonding. All other H atoms were positioned geometrically and allowed to ride on their parent atoms, with C—H distances of 0.93 A˚ , and withUiso(H) = 1.2Ueq(C). Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994); cell refinement: SET4 in CAD-4 EXPRESS; data reduction: XCAD4
(Harms & Wocadlo, 1995); program(s) used to solve structure:
SHELXS97(Sheldrick, 1997); program(s) used to refine structure:
SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication:WinGX(Farrugia, 1999).
This work was supported by Conselho Nacional de Desenvolvimento Cientı´fico e Tecnolo´gico, CNPq, Fundac¸a˜o
de Apoio a` Pesquisa,FUNAPE/UFG. The authors thank the Departamento de Quı´mica, UFSC, for the X-ray single-crystal data collection.
References
Allen, F. H.(2002).Acta Cryst.B58, 380–388.
Barata, L. E. S., Santos, L. S., Ferri, P. H., Phillipson, J. D., Paine, A. & Croft, S. L. (2000).Phytochemistry,55, 589–595.
Cremer, D. & Pople, J. A. (1975).J. Am. Chem. Soc.97, 1354–1358. Enraf–Nonius (1994). CAD-4 EXPRESS. Version 5.1/1.2. Enraf–Nonius,
Delft, The Netherlands.
Farrugia, L. J. (1997).J. Appl. Cryst.30, 565. Farrugia, L. J. (1999).J. Appl. Cryst.32, 837–838.
Gottlieb, O. R. & Yoshida, M. (1990).Lignans: Chemical, Biological and Clinical Properties. Chemistry and Pharmacology of Natural Products, edited by D. C. Ayres & J. D. Loike, pp. 150–181. Cambridge University Press.
Gu, Y., Kar, T. & Scheiner, S. (1999).J. Am. Chem. Soc.121, 9411–9422. Harms, K. & Wocadlo, S. (1995).XCAD4. University of Marburg, Germany. Hwang, B. H. & Sakakibara, A. (1981).Holzforschung,35, 297–300. Jardim, W. F., Pasquini, C., Guimara˜es, J. R. & Faria, L. C. (1990).Water Res.
24, 351–354.
Moss, G. P. (2000).Pure Appl. Chem.72, 1493–1523.
North, A. C. T., Phillips, D. C. & Mathews, F. S. (1968).Acta Cryst.A24, 351– 359.
Oliveira, G. R., Gomes, A. C. F., Santos, N. C., Faria, L. C. & Ferri, P. H. (1994). Abstract of the XXXIVth Brazilian Congress of Chemistry, Porto Alegre, October, pp. 269.
Owsley, D. C. & Bloomfield, J. J. (1977).Synthesis,2, 118–120. Paulino Filho, H. F. (1985). PhD thesis, USP, Sa˜o Paulo, Brazil. Sabitha, G. & Rao, A. V. S. (1987).Synth. Commun.17, 341–354.
Santes, V., Rojas-Lima, S., Santillan, R. L. & Farfan, N. (1999). Monatsh. Chem.130, 1481–1486.
Santos, N. C., Faria, L. C. Azevedo, N. R. & Ferri, P. H. (1994). Abstract of the Ist Meeting on Cerrado of Brazilian Society for Science Progress, Uberlaˆndia, April, p. 43.
Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Go¨ttingen, Germany.
Shridhar, D. R., Sastry, C. V. R., Bansal, O. P. & Rao, P. P. (1981).Synthesis,11, 912–913.
Shridhar, D. R., Sastry, C. V. R., Bansal, O. P. & Rao, P. P. (1986).Indian J. Chem. Sect. B,25, 874–876.
organic papers
supporting information
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Acta Cryst. (2005). E61, o769–o771
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Acta Cryst. (2005). E61, o769–o771 [https://doi.org/10.1107/S160053680500543X]
3-(4-Chlorophenyl)-2
H
-benz[
b
][1,4]oxazine
Ivo Vencato, Pedro H. Ferri, Lourival C. Faria, Suzana C. Santos and Carlito Lariucci
3–4(Chlorophenyl)-2H-benz[b][1,4]oxazine
Crystal data
C14H10ClNO Mr = 243.68
Monoclinic, P21/c
Hall symbol: -P 2ybc
a = 13.861 (3) Å
b = 5.834 (1) Å
c = 14.903 (3) Å
β = 110.65 (3)°
V = 1127.7 (4) Å3 Z = 4
F(000) = 504
Dx = 1.435 Mg m−3
Melting point = 433–434 K Mo Kα radiation, λ = 0.71073 Å Cell parameters from 25 reflections
θ = 9.8–13.8°
µ = 0.32 mm−1 T = 298 K
Prismatic, light brown 0.35 × 0.35 × 0.10 mm
Data collection
Enraf–Nonius CAD-4 diffractometer
Radiation source: fine-focus sealed tube Graphite monochromator
non–profiled ω/2θ scans Absorption correction: psi-scan
(North et al., 1968)
Tmin = 0.901, Tmax = 0.970
2055 measured reflections
1970 independent reflections 1543 reflections with I > 2σ(I)
Rint = 0.016
θmax = 25.0°, θmin = 2.8° h = −16→0
k = −6→0
l = −16→17
2 standard reflections every 120 min intensity decay: <1%
Refinement
Refinement on F2
Least-squares matrix: full
R[F2 > 2σ(F2)] = 0.043 wR(F2) = 0.132 S = 1.05 1970 reflections 161 parameters 3 restraints
Primary atom site location: structure-invariant direct methods
Secondary atom site location: difference Fourier map
Hydrogen site location: inferred from neighbouring sites
H atoms treated by a mixture of independent and constrained refinement
w = 1/[σ2(F
o2) + (0.0668P)2 + 0.5604P]
where P = (Fo2 + 2Fc2)/3
(Δ/σ)max = 0.004
Δρmax = 0.47 e Å−3
Δρmin = −0.27 e Å−3
Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
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Acta Cryst. (2005). E61, o769–o771
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 (Å2)
x y z Uiso*/Ueq
Cl 0.03691 (5) 1.08109 (15) 0.66491 (6) 0.0761 (3) O 0.61639 (11) 0.6664 (3) 0.98852 (11) 0.0501 (4) N 0.55017 (14) 1.0737 (3) 0.88482 (13) 0.0414 (4) C1 0.16683 (17) 1.0306 (4) 0.72801 (17) 0.0471 (6) C2 0.19662 (18) 0.8287 (4) 0.77798 (18) 0.0506 (6) H2 0.1477 0.7203 0.7786 0.061* C3 0.30013 (17) 0.7894 (4) 0.82716 (17) 0.0455 (5) H3 0.3206 0.6536 0.8613 0.055* C4 0.37479 (16) 0.9498 (4) 0.82652 (15) 0.0373 (5) C5 0.34133 (17) 1.1524 (4) 0.77519 (15) 0.0426 (5) H5 0.3897 1.2620 0.7741 0.051* C6 0.23803 (18) 1.1938 (4) 0.72600 (16) 0.0462 (6) H6 0.2168 1.3295 0.6920 0.055* C7 0.48612 (16) 0.9089 (4) 0.87590 (15) 0.0374 (5) C8 0.52260 (19) 0.6694 (4) 0.9082 (2) 0.0532 (7) H8B 0.528 (2) 0.559 (5) 0.8487 (17) 0.064* H8A 0.4771 (19) 0.591 (5) 0.9251 (18) 0.064* C9 0.68859 (16) 0.8209 (4) 0.98249 (15) 0.0404 (5) C10 0.65597 (16) 1.0233 (4) 0.93059 (15) 0.0379 (5) C11 0.72987 (17) 1.1812 (4) 0.92807 (16) 0.0448 (5) H11 0.7095 1.3171 0.8940 0.054* C12 0.83334 (18) 1.1381 (4) 0.97580 (17) 0.0510 (6) H12 0.8824 1.2437 0.9730 0.061* C13 0.86396 (18) 0.9383 (4) 1.02769 (17) 0.0525 (6) H13 0.9337 0.9105 1.0602 0.063* C14 0.79149 (17) 0.7787 (4) 1.03174 (17) 0.0492 (6) H14 0.8121 0.6449 1.0673 0.059*
Atomic displacement parameters (Å2)
U11 U22 U33 U12 U13 U23
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Acta Cryst. (2005). E61, o769–o771
C3 0.0466 (12) 0.0354 (12) 0.0567 (14) −0.0002 (9) 0.0209 (10) 0.0052 (10) C4 0.0396 (11) 0.0328 (11) 0.0397 (11) 0.0004 (9) 0.0143 (9) −0.0018 (9) C5 0.0452 (12) 0.0348 (12) 0.0472 (12) −0.0030 (9) 0.0155 (10) 0.0000 (10) C6 0.0498 (13) 0.0386 (13) 0.0472 (13) 0.0076 (10) 0.0131 (10) 0.0042 (10) C7 0.0427 (11) 0.0316 (11) 0.0392 (11) 0.0003 (9) 0.0159 (9) 0.0010 (9) C8 0.0414 (13) 0.0386 (13) 0.0690 (16) −0.0036 (10) 0.0063 (11) 0.0154 (12) C9 0.0426 (12) 0.0359 (11) 0.0418 (11) −0.0021 (9) 0.0139 (9) −0.0018 (9) C10 0.0395 (11) 0.0329 (11) 0.0407 (11) −0.0003 (9) 0.0133 (9) −0.0035 (9) C11 0.0470 (12) 0.0362 (12) 0.0505 (13) −0.0050 (10) 0.0163 (10) −0.0009 (10) C12 0.0438 (12) 0.0509 (14) 0.0565 (14) −0.0104 (11) 0.0154 (10) −0.0052 (11) C13 0.0377 (12) 0.0593 (16) 0.0536 (14) 0.0012 (11) 0.0077 (10) −0.0062 (12) C14 0.0473 (13) 0.0452 (13) 0.0489 (13) 0.0051 (11) 0.0091 (10) 0.0043 (11)
Geometric parameters (Å, º)
Cl—C1 1.738 (2) C6—H6 0.9300 O—C9 1.373 (3) C7—C8 1.506 (3) O—C8 1.423 (3) C8—H8B 1.12 (2) N—C7 1.283 (3) C8—H8A 0.88 (2) N—C10 1.413 (3) C9—C14 1.377 (3) C1—C2 1.377 (4) C9—C10 1.397 (3) C1—C6 1.379 (3) C10—C11 1.388 (3) C2—C3 1.381 (3) C11—C12 1.381 (3) C2—H2 0.9300 C11—H11 0.9300 C3—C4 1.398 (3) C12—C13 1.380 (4) C3—H3 0.9300 C12—H12 0.9300 C4—C5 1.396 (3) C13—C14 1.386 (3) C4—C7 1.476 (3) C13—H13 0.9300 C5—C6 1.380 (3) C14—H14 0.9300 C5—H5 0.9300
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C1—C6—C5 119.0 (2) C12—C13—C14 120.5 (2) C1—C6—H6 120.5 C12—C13—H13 119.8 C5—C6—H6 120.5 C14—C13—H13 119.8 N—C7—C4 119.60 (19) C9—C14—C13 119.1 (2) N—C7—C8 121.3 (2) C9—C14—H14 120.4 C4—C7—C8 118.91 (19) C13—C14—H14 120.4 O—C8—C7 112.6 (2)
C6—C1—C2—C3 0.0 (4) N—C7—C8—O 31.7 (3) Cl—C1—C2—C3 179.41 (18) C4—C7—C8—O −153.0 (2) C1—C2—C3—C4 −0.4 (4) C8—O—C9—C14 −154.5 (2) C2—C3—C4—C5 0.6 (3) C8—O—C9—C10 28.8 (3) C2—C3—C4—C7 −178.0 (2) O—C9—C10—C11 177.76 (19) C3—C4—C5—C6 −0.4 (3) C14—C9—C10—C11 1.1 (3) C7—C4—C5—C6 178.2 (2) O—C9—C10—N 0.6 (3) C2—C1—C6—C5 0.1 (4) C14—C9—C10—N −176.1 (2) Cl—C1—C6—C5 −179.24 (17) C7—N—C10—C11 169.0 (2) C4—C5—C6—C1 0.0 (3) C7—N—C10—C9 −13.9 (3) C10—N—C7—C4 −178.47 (18) C9—C10—C11—C12 0.1 (3) C10—N—C7—C8 −3.1 (3) N—C10—C11—C12 177.4 (2) C5—C4—C7—N 11.5 (3) C10—C11—C12—C13 −0.9 (4) C3—C4—C7—N −170.0 (2) C11—C12—C13—C14 0.5 (4) C5—C4—C7—C8 −164.0 (2) O—C9—C14—C13 −178.2 (2) C3—C4—C7—C8 14.5 (3) C10—C9—C14—C13 −1.5 (3) C9—O—C8—C7 −43.0 (3) C12—C13—C14—C9 0.7 (4)
Hydrogen-bond geometry (Å, º)
D—H···A D—H H···A D···A D—H···A
C8—H8A···Oi 0.88 (2) 2.60 (2) 3.465 (3) 166 (2)