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Acta Cryst. (2008). E64, o573    [ doi:10.1107/S1600536808003887 ]

1,3-Di-3-pyridyl-2,3-dihydro-1H-naphth[1,2-e][1,3]oxazine

B. Sen, Z. Turgut, E. Pelit and M. Aygün

Abstract top

In the crystal structure of the title compound, C22H17N3O, the oxazine ring has a half-chair conformation. The dihedral angles between the best least-squares plane through the pyridine rings and the planar part (O-C-C-C-N) of the oxazine ring are 72.14 (6) and 35.44 (7)°, the smaller angle involving the pyridine ring adjacent to the oxazine O atom. The molecule has two stereogenic centers at the oxazine carbons, RS and SR. The crystal packing reveals that symmetry-related molecules are linked by intermolecular N-H...N hydrogen bonds to form chains parallel to the b axis.

Comment top

1,3-oxazine heterocycles are of interest because they constitute an important class of natural and non-natural products. Many of them exhibit biological activity such as analgesic, anticonvulsant, antitubercular, antibacterial and anticancer (Kurz et al., 2005; Turgut et al., 2007). In addition, they can be used as intermediates in the synthesis of N-substituted amino alcohols or in enantioselective synthesis of chiral amines. The tautomeric character of the 1,3-O,N-heterocycles offers a great number of synthetic possibilities (Szatmari et al., 2003; Szatmari et al., 2004).

Atoms (C11, C20, C21 and O1) of the oxazine six-membered ring are planar to within 0.014 Å. The oxazine ring adopts a half-chair conformation, with atom C22 and N1 deviating by -0.375 (3) Å and 0.308 (3) Å, respectively, from the mean plane formed by atoms (C11, C20, C21 and O1). The ring puckering parameters for the oxazine ring are Q = 0.451 (2) Å, θ = 126.2 (2)° and φ = 92.4 (3) ° (Cremer & Pople, 1975). The dihedral angles made by the best least-squares plane through all six atoms of the oxazine ring with the mean planes of the pyridine rings (N2/C1—C5) and (N3/C6—C10) are 79.62 (9)° and 36.40 (9)°, respectively. The sum of the angles at N1 of the oxazine ring is 334.1°, in accordance with sp3-hybridization. The H atoms bonded to atoms C22 and C21 of the oxazine ring are axial and trans to one another. The structure is centrosymmetric so the absolute configurations of the two stereogenic centres, C21 and C22, are RS and SR, respectively.

In the crystal structure, intermolecular N1—H1···N3i hydrogen bonds (Table 1) link the molecules to form an infinite one-dimensional polymeric chain. In this manner a C(6) chain (Bernstein et al., 1995) is formed and the axis of the polymeric chain runs co-linear with the crystallographic [010] direction of the monoclinic unit cell (Fig. 2).

Related literature top

For related literature, see: Kurz et al. (2005); Turgut et al. (2007); Szatmari et al. (2003, 2004); Bernstein et al. (1995); Cremer & Pople (1975).

Experimental top

The title compound was prepared by cyclization reactions realised using 2-naphthol and pyridine-3-carbaldehyde in the presence of dry methanolic ammonia (Fig. 3). The structure of the title compound has been clarified by FTIR, MS and NMR techniques and confirmed by elemental analysis.

Pyridin-3-carbaldehyde (2 mmol; freshly distilled if liquid) and 25% methanolic ammonia solution (0.5 mL) were added to a solution of 2-naphthol (1 mmol) in absolute MeOH (0.5 ml). The mixture was left to stand at ambient temperature for 2 days, during which time a crystalline product separated out. The crude product was filtered off, washed with cold MeOH (2x2mL), then purified by column chromatography with ethyl acetate/n-hexane (3:1). Pale-yellow crystals of the title compound, suitable for X-ray analysis, were obtained by slow evaporation of this solution.

1H NMR (CDCl3, δ (p.p.m.)): 5.34 (s, 1H, CH); 5.89 (s, 1H, CH); 7.21–7.89 (m, 10H, ArH); 8.50–8.89 (m, 4H, pyridine)

13C NMR (CDCl3, δ (p.p.m.)): 56.23, 81.75, 124.37, 133.67, 139.76, 148.27, 150.52, 154.3

FTIR(KBr, cm-1, ν) 3335, 3056,3034, 1622,1596,1260,1233,1023,928

Refinement top

All H atoms were located in difference Fourier maps and were freely refined: N—H = 0.97 (2), C—H = 0.95 (2) - 1.04 (2) Å

Computing details top

Data collection: X-AREA (Stoe & Cie, 2002); cell refinement: X-AREA (Stoe & Cie, 2002); data reduction: X-RED32 (Stoe & Cie, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996) and PLATON (Spek, 2003); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. An ORTEPIII (Burnett & Johnson, 1996) view of the title compound with the atomic numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are shown as spheres of arbitrary size.
[Figure 2] Fig. 2. The crystal packing diagram of the title compound showing the infinite zigzag chain along the b axis, formed through N—H···N hydrogen bonding (dashed lines) [Symmetry codes: (*) 1 - x,1/2 + y,1/2 - z].
[Figure 3] Fig. 3. The formation of the title compound.
1,3-Di-3-pyridyl-2,3-dihydro-1H-naphth[1,2-e][1,3]oxazine top
Crystal data top
C22H17N3OF000 = 712
Mr = 339.39Dx = 1.329 Mg m−3
Monoclinic, P21/cMo Kα radiation
λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 10289 reflections
a = 12.1720 (8) Åθ = 1.7–27.2º
b = 8.0444 (6) ŵ = 0.08 mm−1
c = 18.7716 (15) ÅT = 293 (2) K
β = 112.615 (5)ºPrism, pale yellow
V = 1696.7 (2) Å30.28 × 0.22 × 0.12 mm
Z = 4
Data collection top
Stoe IPDSII
diffractometer		3703 independent reflections
Radiation source: fine-focus sealed tube1786 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.124
Detector resolution: 6.67 pixels mm-1θmax = 27.2º
T = 293(2) Kθmin = 2.4º
ω and φ scansh = −15→15
Absorption correction: nonek = −10→10
15207 measured reflectionsl = −24→24
Refinement top
Refinement on F2Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: fullAll H-atom parameters refined
R[F2 > 2σ(F2)] = 0.041  w = 1/[σ2(Fo2) + (0.0317P)2]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.092(Δ/σ)max < 0.001
S = 0.80Δρmax = 0.12 e Å−3
3703 reflectionsΔρmin = −0.13 e Å−3
304 parametersExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0155 (15)
Secondary atom site location: difference Fourier map
Crystal data top
C22H17N3OV = 1696.7 (2) Å3
Mr = 339.39Z = 4
Monoclinic, P21/cMo Kα
a = 12.1720 (8) ŵ = 0.08 mm−1
b = 8.0444 (6) ÅT = 293 (2) K
c = 18.7716 (15) Å0.28 × 0.22 × 0.12 mm
β = 112.615 (5)º
Data collection top
Stoe IPDSII
diffractometer		3703 independent reflections
Absorption correction: none1786 reflections with I > 2σ(I)
15207 measured reflectionsRint = 0.124
Refinement top
R[F2 > 2σ(F2)] = 0.041304 parameters
wR(F2) = 0.092All H-atom parameters refined
S = 0.80Δρmax = 0.12 e Å−3
3703 reflectionsΔρmin = −0.13 e Å−3
Special details top

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) top
xyzUiso*/Ueq
O10.50525 (11)0.70176 (16)0.05782 (6)0.0613 (3)
N10.34476 (13)0.63357 (19)0.09666 (7)0.0530 (4)
N20.07931 (16)0.2535 (2)0.01583 (9)0.0797 (5)
N30.61988 (16)0.4333 (2)0.30101 (8)0.0708 (5)
C10.20165 (16)0.4668 (2)−0.00607 (8)0.0515 (4)
C20.22195 (18)0.3658 (2)−0.05879 (10)0.0624 (5)
C30.1718 (2)0.2087 (3)−0.07310 (11)0.0721 (6)
C40.1012 (2)0.1592 (3)−0.03549 (11)0.0750 (6)
C50.13038 (19)0.4030 (3)0.02947 (10)0.0664 (5)
C60.55109 (16)0.5779 (2)0.17981 (8)0.0518 (4)
C70.54203 (19)0.4545 (2)0.22813 (10)0.0619 (5)
C80.7097 (2)0.5402 (3)0.32714 (11)0.0717 (6)
C90.7258 (2)0.6678 (3)0.28396 (10)0.0713 (6)
C100.64504 (18)0.6866 (2)0.20842 (9)0.0621 (5)
C110.42404 (16)0.7472 (2)−0.01352 (8)0.0521 (4)
C120.4760 (2)0.8298 (2)−0.05937 (10)0.0581 (5)
C130.40609 (19)0.8731 (2)−0.13285 (10)0.0614 (5)
C140.28339 (18)0.8404 (2)−0.16314 (9)0.0571 (5)
C150.2110 (2)0.8834 (3)−0.24001 (10)0.0703 (6)
C160.0929 (2)0.8602 (3)−0.26809 (12)0.0854 (7)
C170.0389 (2)0.7933 (3)−0.22063 (12)0.0884 (7)
C180.10616 (19)0.7473 (3)−0.14611 (10)0.0703 (6)
C190.23078 (17)0.7670 (2)−0.11493 (9)0.0548 (5)
C200.30495 (16)0.7173 (2)−0.03826 (8)0.0506 (4)
C210.25461 (17)0.6395 (2)0.01656 (8)0.0530 (4)
C220.45819 (16)0.5869 (2)0.09848 (8)0.0526 (4)
H10.3522 (17)0.738 (3)0.1247 (10)0.080 (6)*
H20.2726 (17)0.408 (2)−0.0873 (9)0.073 (5)*
H30.1834 (19)0.141 (3)−0.1108 (12)0.099 (7)*
H40.0621 (19)0.051 (3)−0.0461 (11)0.089 (7)*
H50.1146 (18)0.475 (3)0.0680 (10)0.083 (6)*
H70.4767 (18)0.367 (3)0.2099 (10)0.077 (6)*
H80.7714 (19)0.522 (3)0.3822 (11)0.094 (7)*
H90.7932 (19)0.744 (3)0.3052 (10)0.083 (6)*
H100.6560 (18)0.777 (3)0.1759 (10)0.090 (6)*
H120.5600 (18)0.853 (2)−0.0360 (9)0.064 (5)*
H130.4472 (17)0.928 (2)−0.1648 (9)0.076 (5)*
H150.2541 (18)0.935 (3)−0.2732 (10)0.087 (6)*
H160.041 (2)0.891 (3)−0.3203 (13)0.113 (8)*
H17−0.047 (2)0.776 (3)−0.2404 (12)0.107 (8)*
H180.0647 (16)0.705 (2)−0.1138 (9)0.066 (5)*
H210.1904 (15)0.710 (2)0.0184 (8)0.055 (5)*
H220.4510 (15)0.472 (2)0.0725 (8)0.057 (5)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0548 (8)0.0777 (9)0.0510 (6)−0.0024 (6)0.0199 (6)0.0111 (6)
N10.0553 (10)0.0593 (10)0.0451 (7)−0.0015 (7)0.0201 (7)−0.0059 (6)
N20.0853 (14)0.0791 (13)0.0802 (10)−0.0210 (10)0.0380 (10)−0.0002 (9)
N30.0791 (13)0.0742 (12)0.0544 (9)−0.0034 (10)0.0205 (8)0.0110 (7)
C10.0464 (11)0.0572 (11)0.0479 (8)−0.0006 (8)0.0147 (8)0.0004 (7)
C20.0677 (14)0.0614 (12)0.0625 (10)−0.0053 (10)0.0296 (10)−0.0082 (9)
C30.0791 (16)0.0637 (13)0.0711 (12)−0.0062 (11)0.0261 (11)−0.0124 (10)
C40.0768 (16)0.0669 (14)0.0712 (12)−0.0135 (12)0.0172 (11)0.0009 (11)
C50.0717 (15)0.0705 (13)0.0615 (10)−0.0078 (11)0.0305 (10)−0.0007 (10)
C60.0556 (12)0.0525 (10)0.0492 (9)0.0008 (9)0.0223 (8)−0.0024 (7)
C70.0701 (15)0.0624 (12)0.0539 (10)−0.0053 (10)0.0246 (10)0.0031 (9)
C80.0690 (16)0.0815 (15)0.0561 (11)−0.0004 (12)0.0146 (10)0.0068 (10)
C90.0666 (15)0.0794 (15)0.0596 (11)−0.0132 (12)0.0152 (10)0.0003 (10)
C100.0683 (14)0.0639 (12)0.0529 (10)−0.0049 (10)0.0217 (9)0.0019 (9)
C110.0582 (13)0.0539 (10)0.0433 (8)0.0026 (9)0.0183 (8)0.0005 (7)
C120.0592 (14)0.0595 (11)0.0568 (10)−0.0026 (10)0.0236 (9)0.0017 (8)
C130.0733 (15)0.0580 (11)0.0573 (10)−0.0009 (10)0.0301 (10)0.0073 (8)
C140.0625 (14)0.0563 (11)0.0516 (9)0.0025 (9)0.0209 (9)0.0041 (8)
C150.0777 (18)0.0720 (13)0.0576 (11)0.0021 (11)0.0219 (11)0.0106 (9)
C160.0798 (19)0.1046 (18)0.0596 (12)−0.0013 (14)0.0131 (12)0.0173 (12)
C170.0630 (18)0.119 (2)0.0697 (13)0.0006 (14)0.0104 (11)0.0228 (12)
C180.0620 (15)0.0829 (14)0.0636 (11)−0.0025 (11)0.0214 (10)0.0088 (10)
C190.0585 (14)0.0518 (10)0.0526 (9)0.0029 (9)0.0196 (8)0.0003 (8)
C200.0554 (13)0.0495 (10)0.0484 (8)0.0016 (8)0.0215 (8)−0.0003 (7)
C210.0542 (12)0.0591 (11)0.0475 (9)0.0053 (9)0.0217 (8)0.0007 (8)
C220.0566 (13)0.0551 (11)0.0480 (9)0.0021 (9)0.0222 (8)0.0009 (8)
Geometric parameters (Å, °) top
O1—C111.3732 (19)C9—C101.389 (3)
O1—C221.4492 (19)C9—H90.98 (2)
N1—C221.419 (2)C10—H100.99 (2)
N1—C211.483 (2)C11—C201.363 (2)
N1—H10.97 (2)C11—C121.415 (2)
N2—C41.331 (3)C12—C131.359 (3)
N2—C51.332 (2)C12—H120.962 (19)
N3—C81.328 (3)C13—C141.404 (3)
N3—C71.342 (2)C13—H131.017 (18)
C1—C21.374 (2)C14—C151.414 (2)
C1—C51.381 (2)C14—C191.422 (2)
C1—C211.522 (2)C15—C161.341 (3)
C2—C31.384 (3)C15—H151.040 (19)
C2—H21.017 (17)C16—C171.402 (3)
C3—C41.365 (3)C16—H160.97 (2)
C3—H30.95 (2)C17—C181.372 (3)
C4—H40.98 (2)C17—H170.98 (2)
C5—H51.002 (19)C18—C191.409 (3)
C6—C101.374 (2)C18—H180.988 (17)
C6—C71.378 (2)C19—C201.431 (2)
C6—C221.512 (2)C20—C211.520 (2)
C7—H71.02 (2)C21—H210.975 (16)
C8—C91.368 (3)C22—H221.032 (17)
C8—H81.03 (2)
C11—O1—C22113.65 (13)C13—C12—C11119.1 (2)
C22—N1—C21111.52 (12)C13—C12—H12123.7 (10)
C22—N1—H1109.1 (11)C11—C12—H12117.2 (10)
C21—N1—H1113.5 (11)C12—C13—C14121.13 (17)
C4—N2—C5116.46 (18)C12—C13—H13116.8 (11)
C8—N3—C7116.90 (17)C14—C13—H13122.0 (10)
C2—C1—C5116.69 (17)C13—C14—C15121.03 (17)
C2—C1—C21124.50 (16)C13—C14—C19119.30 (15)
C5—C1—C21118.79 (15)C15—C14—C19119.65 (19)
C1—C2—C3119.44 (18)C16—C15—C14121.3 (2)
C1—C2—H2119.6 (10)C16—C15—H15122.1 (11)
C3—C2—H2120.9 (10)C14—C15—H15116.6 (11)
C4—C3—C2119.0 (2)C15—C16—C17119.8 (2)
C4—C3—H3121.6 (14)C15—C16—H16123.2 (14)
C2—C3—H3119.3 (13)C17—C16—H16116.9 (14)
N2—C4—C3123.3 (2)C18—C17—C16120.6 (2)
N2—C4—H4116.1 (12)C18—C17—H17118.8 (13)
C3—C4—H4120.6 (12)C16—C17—H17120.5 (12)
N2—C5—C1125.15 (18)C17—C18—C19121.2 (2)
N2—C5—H5117.1 (11)C17—C18—H18118.3 (10)
C1—C5—H5117.7 (11)C19—C18—H18120.5 (10)
C10—C6—C7117.81 (16)C18—C19—C14117.29 (16)
C10—C6—C22123.44 (15)C18—C19—C20123.26 (16)
C7—C6—C22118.75 (17)C14—C19—C20119.45 (17)
N3—C7—C6124.0 (2)C11—C20—C19118.07 (14)
N3—C7—H7114.2 (10)C11—C20—C21119.66 (14)
C6—C7—H7121.8 (10)C19—C20—C21122.23 (17)
N3—C8—C9123.56 (19)N1—C21—C20111.47 (15)
N3—C8—H8117.4 (12)N1—C21—C1108.81 (14)
C9—C8—H8119.0 (12)C20—C21—C1115.12 (13)
C8—C9—C10118.7 (2)N1—C21—H21105.9 (9)
C8—C9—H9121.3 (11)C20—C21—H21108.8 (9)
C10—C9—H9120.0 (11)C1—C21—H21106.2 (10)
C6—C10—C9119.09 (18)N1—C22—O1113.38 (14)
C6—C10—H10121.0 (11)N1—C22—C6112.33 (12)
C9—C10—H10119.9 (12)O1—C22—C6105.59 (14)
C20—C11—O1123.91 (14)N1—C22—H22108.7 (9)
C20—C11—C12122.79 (15)O1—C22—H22107.5 (8)
O1—C11—C12113.30 (17)C6—C22—H22109.2 (9)
C5—C1—C2—C3−0.3 (3)C13—C14—C19—C18175.59 (17)
C21—C1—C2—C3178.03 (18)C15—C14—C19—C18−2.6 (3)
C1—C2—C3—C41.4 (3)C13—C14—C19—C20−4.4 (2)
C5—N2—C4—C30.1 (3)C15—C14—C19—C20177.40 (16)
C2—C3—C4—N2−1.3 (3)O1—C11—C20—C19−178.17 (14)
C4—N2—C5—C11.0 (3)C12—C11—C20—C192.2 (2)
C2—C1—C5—N2−0.9 (3)O1—C11—C20—C214.2 (2)
C21—C1—C5—N2−179.35 (18)C12—C11—C20—C21−175.39 (15)
C8—N3—C7—C60.7 (3)C18—C19—C20—C11−178.01 (17)
C10—C6—C7—N3−0.6 (3)C14—C19—C20—C111.9 (2)
C22—C6—C7—N3179.19 (17)C18—C19—C20—C21−0.5 (3)
C7—N3—C8—C9−0.1 (3)C14—C19—C20—C21179.47 (16)
N3—C8—C9—C10−0.6 (3)C22—N1—C21—C20−41.2 (2)
C7—C6—C10—C9−0.1 (3)C22—N1—C21—C186.79 (17)
C22—C6—C10—C9−179.90 (17)C11—C20—C21—N110.0 (2)
C8—C9—C10—C60.7 (3)C19—C20—C21—N1−167.51 (15)
C22—O1—C11—C2013.0 (2)C11—C20—C21—C1−114.56 (18)
C22—O1—C11—C12−167.37 (14)C19—C20—C21—C167.9 (2)
C20—C11—C12—C13−3.9 (3)C2—C1—C21—N1−109.53 (19)
O1—C11—C12—C13176.41 (15)C5—C1—C21—N168.8 (2)
C11—C12—C13—C141.3 (3)C2—C1—C21—C2016.4 (3)
C12—C13—C14—C15−179.09 (18)C5—C1—C21—C20−165.26 (17)
C12—C13—C14—C192.7 (3)C21—N1—C22—O161.15 (19)
C13—C14—C15—C16−176.6 (2)C21—N1—C22—C6−179.25 (14)
C19—C14—C15—C161.6 (3)C11—O1—C22—N1−46.19 (18)
C14—C15—C16—C170.5 (4)C11—O1—C22—C6−169.58 (13)
C15—C16—C17—C18−1.6 (4)C10—C6—C22—N1−111.91 (19)
C16—C17—C18—C190.5 (4)C7—C6—C22—N168.3 (2)
C17—C18—C19—C141.6 (3)C10—C6—C22—O112.1 (2)
C17—C18—C19—C20−178.5 (2)C7—C6—C22—O1−167.64 (15)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N1—H1···N3i0.98 (2)2.04 (2)3.009 (2)170.7 (17)
Symmetry codes: (i) −x+1, y+1/2, −z+1/2.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N1—H1···N3i0.98 (2)2.04 (2)3.009 (2)170.7 (17)
Symmetry codes: (i) −x+1, y+1/2, −z+1/2.
Acknowledgements top

The authors acknowledge the Faculty of Arts and Sciences, Ondokuz Mayıs University, Turkey, for the use of the Stoe IPDSII diffractometer (purchased under grant No. F.279 of the University Research Fund), and Dokuz Eylül University Research Funds (Project No. 04.KB.FEN.100).

references
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