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

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ISSN: 2056-9890

1-Phenyl-1H-naphtho­[1,2-e][1,3]oxazin-3(2H)-one

aDepartment of Chemistry, University of Sargodha, Sargodha, Pakistan, and bDepartment of Physics, University of Sargodha, Sargodha, Pakistan
*Correspondence e-mail: dmntahir_uos@yahoo.com

(Received 5 September 2010; accepted 6 September 2010; online 11 September 2010)

In the title compound, C18H13NO2, the naphthalene (r.m.s. deviation = 0.025 Å) and benzaldehyde (r.m.s. deviation = 0.006 Å) groups are oriented at a dihedral angle of 89.48 (4)°. The oxazine group is oriented at dihedral angles of 13.36 (4) and 85.08 (5)°, respectively, with respect to the naphthalene and benzaldehyde fragments. In the crystal, inversion dimers linked by pairs of C—H⋯O hydrogen bonds generate R22(8) loops. The dimers are linked into [010] chains via N—H⋯O hydrogen bonds. Weak C—H⋯π links and aromatic ππ stacking between the centroids of the naphthalene phenyl rings [centroid–centroid separation = 3.5977 (8) Å] help to consolidate the packing.

Related literature

For background to oxazinones, see: Patel et al. (1999[Patel, M., McHugh, R. J. Jr, Cordova, B. C., Klabe, R. M., Erickson-Viitanen, S., Trainor, G. L. & Ko, S. S. (1999). Bioorg. Med. Chem. Lett. 9, 3221-3224.]); Waxman & Darke (2000[Waxman, L. & Darke, P. L. (2000). Antiviral Chem. Chemother. 11, 1-22.]). For graph-set notation, see: 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
  • C18H13NO2

  • Mr = 275.29

  • Monoclinic, P 21 /c

  • a = 11.5625 (4) Å

  • b = 16.9228 (5) Å

  • c = 7.2394 (2) Å

  • β = 98.155 (1)°

  • V = 1402.21 (7) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 296 K

  • 0.32 × 0.22 × 0.22 mm

Data collection
  • Bruker Kappa APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2005[Bruker (2005). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.980, Tmax = 0.982

  • 9236 measured reflections

  • 2533 independent reflections

  • 1961 reflections with I > 2σ(I)

  • Rint = 0.022

Refinement
  • R[F2 > 2σ(F2)] = 0.039

  • wR(F2) = 0.111

  • S = 1.03

  • 2533 reflections

  • 190 parameters

  • H-atom parameters constrained

  • Δρmax = 0.16 e Å−3

  • Δρmin = −0.15 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg2 is the centroid of the C1–C6 phenyl ring.

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯O2i 0.86 2.07 2.8698 (17) 155
C8—H8⋯O1ii 0.93 2.58 3.4725 (18) 161
C16—H16⋯Cg2iii 0.93 2.92 3.722 (2) 145
Symmetry codes: (i) [x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]; (ii) -x+2, -y, -z+2; (iii) -x+1, -y, -z+1.

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, 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 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]) and PLATON.

Supporting information


Comment top

Oxazinones are an important class of heterocyclic compounds with a diverse range of biological activities (Patel et al., 1999; Waxman & Darke, 2000). During recent studies for the search of efficient, simple and green method for the preparation of naphthalene-condensed 1,3-oxazin-3-one derivatives, we have obtained the title compound (I, Fig. 1).

In the title compound, the naphthalene group A (C1—C10) and moiety B (C11—C17) of benzaldehyde group are planar with r. m. s. deviations of 0.0252 and 0.0056 Å, respectively. The dihedral angle between A/B is 89.48 (4)°. The fused group C (O1/C18/O2/N1) is also planar with r. m. s. deviation of 0.0037 Å. The dihedral angle between A/C and B/C is 13.36 (4) and 85.08 (5)°, respectively. The title compound is dimerized due to H-bonding of C—H···O type (Table 1, Fig. 2) with R22(8) ring motifs (Bernstein et al., 1995). The dimers are interlinked due to N—H···O type of H-bondings (Table 1, Fig. 2). There exists ππ interaction between the centroids of phenyl rings (C1/C6—C10) at a distance of 3.5977 (8) Å [symmetry code: 2 - x, - y, 1 - z]. The molecules are stabilized in the form of infinite one dimensional polymeric chains extending along the c axis.

Related literature top

For background to oxazinones, see: Patel et al. (1999); Waxman & Darke (2000). For graph-set notation, see: Bernstein et al. (1995).

Experimental top

A mixture of β-naphthol (1.0 mmol), benzaldehyde (1.0 mmol), urea (1.0 mmol) and CuCl2 (0.1 mm mol) as a catalyst, were heated at 393 K in a round bottom flask for 3 h. The reaction was monitored through TLC. After completion of the reaction, the mixture was cooled to room temperature and washed thoroughly with distilled water. The crude product obtained was recrystallized from petroleum ether:ethyl acetate (1:5) to affoard colourless rods of (I) after 24 h.

Refinement top

The H-atoms were positioned geometrically (C–H = 0.93–0.96 Å) and were included in the refinement in the riding model approximation, with Uiso(H) = xUeq(C), where x = 1.5 for methyl and x = 1.2 for aryl H-atoms.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. View of (I) with displacement ellipsoids drawn at the 50% probability level. H-atoms are shown as small spheres of arbitrary radii.
[Figure 2] Fig. 2. The partial packing of (I), which shows that molecules are dimerized which are interlinked in one dimensional infinite polymeric chains.
1-Phenyl-1H-naphtho[1,2-e][1,3]oxazin-3(2H)-one top
Crystal data top
C18H13NO2F(000) = 576
Mr = 275.29Dx = 1.304 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 1961 reflections
a = 11.5625 (4) Åθ = 2.2–25.3°
b = 16.9228 (5) ŵ = 0.09 mm1
c = 7.2394 (2) ÅT = 296 K
β = 98.155 (1)°Rod, colourless
V = 1402.21 (7) Å30.32 × 0.22 × 0.22 mm
Z = 4
Data collection top
Bruker Kappa APEXII CCD
diffractometer
2533 independent reflections
Radiation source: fine-focus sealed tube1961 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.022
Detector resolution: 8.10 pixels mm-1θmax = 25.3°, θmin = 2.2°
ω scansh = 1313
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
k = 1820
Tmin = 0.980, Tmax = 0.982l = 86
9236 measured reflections
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)] = 0.039Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.111H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.0535P)2 + 0.2624P]
where P = (Fo2 + 2Fc2)/3
2533 reflections(Δ/σ)max < 0.001
190 parametersΔρmax = 0.16 e Å3
0 restraintsΔρmin = 0.15 e Å3
Crystal data top
C18H13NO2V = 1402.21 (7) Å3
Mr = 275.29Z = 4
Monoclinic, P21/cMo Kα radiation
a = 11.5625 (4) ŵ = 0.09 mm1
b = 16.9228 (5) ÅT = 296 K
c = 7.2394 (2) Å0.32 × 0.22 × 0.22 mm
β = 98.155 (1)°
Data collection top
Bruker Kappa APEXII CCD
diffractometer
2533 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
1961 reflections with I > 2σ(I)
Tmin = 0.980, Tmax = 0.982Rint = 0.022
9236 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0390 restraints
wR(F2) = 0.111H-atom parameters constrained
S = 1.03Δρmax = 0.16 e Å3
2533 reflectionsΔρmin = 0.15 e Å3
190 parameters
Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

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) top
xyzUiso*/Ueq
O10.89839 (10)0.06939 (6)0.83483 (14)0.0559 (4)
O20.91991 (11)0.19318 (7)0.92712 (18)0.0737 (5)
N10.85664 (10)0.16926 (7)0.62191 (18)0.0510 (4)
C10.81409 (12)0.02577 (8)0.3762 (2)0.0436 (5)
C20.75736 (14)0.01136 (10)0.1926 (2)0.0563 (5)
C30.73596 (18)0.07145 (12)0.0667 (3)0.0715 (7)
C40.77142 (19)0.14822 (12)0.1148 (3)0.0767 (8)
C50.82829 (16)0.16422 (10)0.2880 (3)0.0656 (7)
C60.85044 (12)0.10406 (8)0.4248 (2)0.0488 (5)
C70.90596 (13)0.11995 (8)0.6071 (2)0.0523 (5)
C80.92163 (13)0.06237 (8)0.7386 (2)0.0502 (5)
C90.88322 (12)0.01469 (8)0.6891 (2)0.0435 (4)
C100.83343 (11)0.03472 (8)0.51467 (19)0.0406 (4)
C110.79834 (12)0.11910 (8)0.4725 (2)0.0434 (4)
C120.66655 (12)0.13238 (8)0.4466 (2)0.0459 (5)
C130.61359 (16)0.18002 (12)0.3073 (3)0.0771 (7)
C140.49394 (18)0.19161 (15)0.2832 (3)0.0978 (9)
C150.42673 (16)0.15621 (12)0.3962 (3)0.0782 (7)
C160.47770 (16)0.10947 (12)0.5371 (3)0.0766 (7)
C170.59754 (15)0.09745 (10)0.5628 (3)0.0653 (6)
C180.89155 (13)0.14824 (9)0.7974 (2)0.0523 (5)
H10.869620.217420.592960.0612*
H20.734380.039770.157470.0675*
H30.697330.060990.052400.0857*
H40.756080.188730.027990.0920*
H50.853170.215540.317350.0787*
H70.932330.170840.637800.0627*
H80.957070.073590.859220.0602*
H110.826860.134190.356240.0520*
H130.658510.204960.227680.0926*
H140.459480.224290.187620.1174*
H150.346240.163710.377980.0938*
H160.432000.085370.616760.0919*
H170.631550.065360.659830.0783*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0719 (7)0.0430 (6)0.0505 (6)0.0007 (5)0.0006 (5)0.0011 (5)
O20.0814 (9)0.0577 (7)0.0769 (8)0.0065 (6)0.0061 (7)0.0244 (6)
N10.0508 (7)0.0327 (6)0.0675 (9)0.0037 (5)0.0017 (6)0.0014 (6)
C10.0422 (8)0.0404 (8)0.0512 (8)0.0057 (6)0.0170 (6)0.0019 (6)
C20.0645 (10)0.0564 (9)0.0502 (9)0.0054 (8)0.0162 (7)0.0021 (8)
C30.0857 (13)0.0788 (13)0.0523 (10)0.0123 (10)0.0180 (9)0.0131 (9)
C40.0951 (15)0.0696 (12)0.0709 (13)0.0161 (10)0.0309 (11)0.0278 (10)
C50.0740 (12)0.0438 (9)0.0859 (13)0.0071 (8)0.0352 (10)0.0134 (9)
C60.0459 (8)0.0381 (8)0.0669 (10)0.0049 (6)0.0236 (7)0.0035 (7)
C70.0479 (8)0.0346 (7)0.0771 (11)0.0021 (6)0.0187 (8)0.0068 (7)
C80.0462 (8)0.0431 (8)0.0610 (9)0.0017 (6)0.0067 (7)0.0122 (7)
C90.0435 (8)0.0375 (7)0.0498 (8)0.0027 (6)0.0080 (6)0.0004 (6)
C100.0374 (7)0.0352 (7)0.0506 (8)0.0022 (5)0.0113 (6)0.0032 (6)
C110.0459 (8)0.0354 (7)0.0491 (8)0.0030 (6)0.0077 (6)0.0045 (6)
C120.0459 (8)0.0357 (7)0.0553 (9)0.0012 (6)0.0042 (6)0.0004 (6)
C130.0565 (10)0.0874 (13)0.0853 (13)0.0041 (9)0.0026 (9)0.0366 (11)
C140.0629 (12)0.1150 (18)0.1095 (17)0.0172 (12)0.0088 (12)0.0423 (14)
C150.0478 (10)0.0796 (13)0.1042 (15)0.0064 (9)0.0009 (10)0.0069 (12)
C160.0562 (11)0.0755 (12)0.1031 (15)0.0015 (9)0.0287 (10)0.0056 (11)
C170.0546 (10)0.0646 (11)0.0795 (12)0.0073 (8)0.0192 (8)0.0200 (9)
C180.0481 (8)0.0421 (8)0.0653 (10)0.0026 (6)0.0034 (7)0.0061 (8)
Geometric parameters (Å, º) top
O1—C91.3958 (17)C12—C171.373 (2)
O1—C181.3617 (18)C12—C131.366 (3)
O2—C181.2167 (19)C13—C141.384 (3)
N1—C111.4622 (19)C14—C151.346 (3)
N1—C181.3259 (19)C15—C161.358 (3)
N1—H10.8600C16—C171.387 (3)
C1—C21.417 (2)C2—H20.9300
C1—C101.4280 (19)C3—H30.9300
C1—C61.4191 (19)C4—H40.9300
C2—C31.365 (3)C5—H50.9300
C3—C41.392 (3)C7—H70.9300
C4—C51.358 (3)C8—H80.9300
C5—C61.418 (2)C11—H110.9800
C6—C71.409 (2)C13—H130.9300
C7—C81.356 (2)C14—H140.9300
C8—C91.4075 (19)C15—H150.9300
C9—C101.355 (2)C16—H160.9300
C10—C111.5039 (19)C17—H170.9300
C11—C121.525 (2)
C9—O1—C18120.13 (11)C15—C16—C17120.35 (19)
C11—N1—C18126.78 (12)C12—C17—C16120.75 (18)
C11—N1—H1117.00O2—C18—N1125.73 (14)
C18—N1—H1117.00O1—C18—O2117.21 (13)
C2—C1—C6118.33 (13)O1—C18—N1117.05 (13)
C6—C1—C10118.94 (13)C1—C2—H2120.00
C2—C1—C10122.72 (13)C3—C2—H2120.00
C1—C2—C3120.94 (16)C2—C3—H3120.00
C2—C3—C4120.63 (19)C4—C3—H3120.00
C3—C4—C5120.27 (19)C3—C4—H4120.00
C4—C5—C6121.17 (16)C5—C4—H4120.00
C5—C6—C7122.02 (14)C4—C5—H5119.00
C1—C6—C5118.64 (14)C6—C5—H5119.00
C1—C6—C7119.33 (13)C6—C7—H7119.00
C6—C7—C8121.20 (13)C8—C7—H7119.00
C7—C8—C9118.75 (13)C7—C8—H8121.00
O1—C9—C10122.00 (12)C9—C8—H8121.00
O1—C9—C8114.88 (12)N1—C11—H11108.00
C8—C9—C10123.11 (13)C10—C11—H11108.00
C1—C10—C11121.82 (12)C12—C11—H11108.00
C1—C10—C9118.59 (12)C12—C13—H13120.00
C9—C10—C11119.58 (12)C14—C13—H13120.00
C10—C11—C12113.63 (11)C13—C14—H14120.00
N1—C11—C12110.68 (11)C15—C14—H14120.00
N1—C11—C10108.56 (11)C14—C15—H15120.00
C11—C12—C13120.86 (14)C16—C15—H15120.00
C11—C12—C17121.24 (13)C15—C16—H16120.00
C13—C12—C17117.89 (15)C17—C16—H16120.00
C12—C13—C14120.81 (18)C12—C17—H17120.00
C13—C14—C15120.9 (2)C16—C17—H17120.00
C14—C15—C16119.30 (18)
C18—O1—C9—C8164.13 (13)C5—C6—C7—C8176.94 (15)
C18—O1—C9—C1016.9 (2)C6—C7—C8—C91.2 (2)
C9—O1—C18—O2170.95 (14)C7—C8—C9—O1177.44 (13)
C9—O1—C18—N17.8 (2)C7—C8—C9—C101.5 (2)
C18—N1—C11—C1027.00 (19)O1—C9—C10—C1175.98 (12)
C18—N1—C11—C1298.36 (16)O1—C9—C10—C113.0 (2)
C11—N1—C18—O115.8 (2)C8—C9—C10—C12.9 (2)
C11—N1—C18—O2165.56 (15)C8—C9—C10—C11178.08 (13)
C6—C1—C2—C31.4 (2)C1—C10—C11—N1164.84 (12)
C10—C1—C2—C3177.10 (16)C1—C10—C11—C1271.56 (17)
C2—C1—C6—C50.1 (2)C9—C10—C11—N116.17 (17)
C2—C1—C6—C7179.36 (14)C9—C10—C11—C12107.43 (15)
C10—C1—C6—C5178.41 (14)N1—C11—C12—C1399.58 (17)
C10—C1—C6—C70.9 (2)N1—C11—C12—C1779.96 (17)
C2—C1—C10—C9176.78 (14)C10—C11—C12—C13137.98 (16)
C2—C1—C10—C112.2 (2)C10—C11—C12—C1742.48 (19)
C6—C1—C10—C91.7 (2)C11—C12—C13—C14179.58 (17)
C6—C1—C10—C11179.35 (13)C17—C12—C13—C140.9 (3)
C1—C2—C3—C41.2 (3)C11—C12—C17—C16179.52 (16)
C2—C3—C4—C50.2 (3)C13—C12—C17—C160.9 (3)
C3—C4—C5—C61.5 (3)C12—C13—C14—C150.1 (3)
C4—C5—C6—C11.3 (3)C13—C14—C15—C160.9 (3)
C4—C5—C6—C7177.92 (17)C14—C15—C16—C170.9 (3)
C1—C6—C7—C82.3 (2)C15—C16—C17—C120.1 (3)
Hydrogen-bond geometry (Å, º) top
Cg2 is the centroid of the C1–C6 phenyl ring.
D—H···AD—HH···AD···AD—H···A
N1—H1···O2i0.862.072.8698 (17)155
C8—H8···O1ii0.932.583.4725 (18)161
C16—H16···Cg2iii0.932.923.722 (2)145
Symmetry codes: (i) x, y+1/2, z1/2; (ii) x+2, y, z+2; (iii) x+1, y, z+1.

Experimental details

Crystal data
Chemical formulaC18H13NO2
Mr275.29
Crystal system, space groupMonoclinic, P21/c
Temperature (K)296
a, b, c (Å)11.5625 (4), 16.9228 (5), 7.2394 (2)
β (°) 98.155 (1)
V3)1402.21 (7)
Z4
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.32 × 0.22 × 0.22
Data collection
DiffractometerBruker Kappa APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.980, 0.982
No. of measured, independent and
observed [I > 2σ(I)] reflections
9236, 2533, 1961
Rint0.022
(sin θ/λ)max1)0.600
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.039, 0.111, 1.03
No. of reflections2533
No. of parameters190
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.16, 0.15

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009), WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
Cg2 is the centroid of the C1–C6 phenyl ring.
D—H···AD—HH···AD···AD—H···A
N1—H1···O2i0.862.072.8698 (17)155
C8—H8···O1ii0.932.583.4725 (18)161
C16—H16···Cg2iii0.932.923.722 (2)145
Symmetry codes: (i) x, y+1/2, z1/2; (ii) x+2, y, z+2; (iii) x+1, y, z+1.
 

Acknowledgements

The authors acknowledge the provision of funds for the purchase of the diffractometer and encouragement by Dr Muhammad Akram Chaudhary, Vice Chancellor, University of Sargodha, Pakistan.

References

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