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Acta Crystallogr Sect E Struct Rep Online. 2010 May 1; 66(Pt 5): o1131.
Published online 2010 April 21. doi:  10.1107/S1600536810013851
PMCID: PMC2979135

1-[(E)-(2-Phenoxy­anilino)methyl­ene]naphthalen-2(1H)-one

Abstract

The mol­ecule of the title compound, C23H17NO2, a Schiff base derived from 2-hydr­oxy-1-naphthaldehyde, crystallizes in the keto–amine tautomeric form. The dihedral angle between the aniline and hydroxy­benzene rings is 77.41 (17)°, whereas the planes of the naphthaldehyde and fused aniline benzene rings are nearly coplanar, making a dihedral angle of 8.29 (15)°. Intra­molecular N—H(...)O hydrogen bonding, a characteristic hydrogen bond for Schiff bases, helps to stabilize the mol­ecular structure. Weak inter­molecular C—H(...)π inter­actions are present in the crystal structure.

Related literature

For Schiff bases, see: Caligaris et al. (1972 [triangle]); Caligaris & Randaccio et al. (1987 [triangle]); Salman et al. (1990 [triangle]); Popović et al. (2001 [triangle]); Garnovskii et al. (1993 [triangle]); Pyrz et al. (1985 [triangle]); Hadjoudis et al. (1987 [triangle]). For the HOMA (harmonic oscillator model of aromaticity) index, see: Krygowski et al. (1993 [triangle]). For similar structures, see: Özek et al. (2004 [triangle]); Takano et al. (2009 [triangle]).

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Object name is e-66-o1131-scheme1.jpg

Experimental

Crystal data

  • C23H17NO2
  • M r = 339.38
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o1131-efi1.jpg
  • a = 14.6428 (11) Å
  • b = 5.6297 (3) Å
  • c = 42.602 (3) Å
  • β = 101.175 (6)°
  • V = 3445.3 (4) Å3
  • Z = 8
  • Mo Kα radiation
  • μ = 0.08 mm−1
  • T = 296 K
  • 0.40 × 0.34 × 0.23 mm

Data collection

  • Stoe IPDSII diffractometer
  • Absorption correction: integration (X-RED; Stoe & Cie, 2002 [triangle]) T min = 0.960, T max = 0.996
  • 11832 measured reflections
  • 2565 independent reflections
  • 1522 reflections with I > 2σ(I)
  • R int = 0.212
  • θmax = 23.6°

Refinement

  • R[F 2 > 2σ(F 2)] = 0.115
  • wR(F 2) = 0.331
  • S = 1.06
  • 2565 reflections
  • 236 parameters
  • H-atom parameters constrained
  • Δρmax = 0.30 e Å−3
  • Δρmin = −0.39 e Å−3

Data collection: X-AREA (Stoe & Cie, 2002 [triangle]); cell refinement: X-AREA; data reduction: X-RED32 (Stoe & Cie, 2002 [triangle]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 [triangle]); software used to prepare material for publication: WinGX (Farrugia, 1999 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810013851/si2256sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810013851/si2256Isup2.hkl

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

Acknowledgments

The authors wish to acknowledge the Faculty of Arts and Sciences of Ondokuz Mayıs University, Turkey, for the use of the Stoe IPDSII diffractometer (purchased under grant No. F279 of the University Research Grant of Ondokuz Mayıs University).

supplementary crystallographic information

Comment

2-Hydroxy-Schiff bases are formed by reactions of salicylaldehyde and 2-hydroxy-1-naphthaldehyde with various amines (Caligaris et al., 1972). In this study, a Schiff base derivatived from 2-hydroxy-1-naphthaldehyde was examined. In contrast to salicylaldimine derivatives, the Schiff bases of 2-hydroxy-1-naphthaldehyde have been rarely investigated (Salman et al., 1990; Popović et al., 2001). Schiff base ligands play a vital role in coordination chemistry due to their metal binding ability (Garnovskii et al., 1993). In addition, Schiff bases and their metal complexes have wide applications in biological systems (Pyrz et al., 1985).

The structure of o-hydroxy aromatic Schiff base has drawn attention due to their keto-enol tautomerism in recent years (Hadjoudis et al., 1987). As being characteristic feature of Schiff bases there are two alternative intra-molecular hydrogen bonds depending on the type of tautomer. The structure with intra-molecular N—H···O hydrogen bond is called keto tautomer. The enol tautomer is, on the other hand, a structure involving O—H···N type hydrogen bond (Caligaris & Randaccio et al., 1987). Details of hydrogen bond geometry are given in Table 1.

The proton transfer responsible for the tautomerization requires a small amount of energy which can be obtained by temperature change or light (Caligaris & Randaccio et al., 1987). The proton transfer reaction causes the bond distances to deviate from the ideal value 1.338 Å, which leads to a decrease in aromaticity of the ring. In order to investigate deformation in π-electron delocalization of aromatic rings, HOMA (Harmonic Oscillator Model of Aromaticity) index is a useful tool. The HOMA index is equal to unity for purely aromatic systems and zero for non-aromatic systems (Krygowski et al., 1993). The HOMA index of the naphthalene ring of (I) was calculated as 0.670, which is fairly less than the HOMA index of aromatic naphthalene. It can be inferred that π-electron delocalization of the ring involving proton transfer is considerably deformed.

The molecule of (I) is generated by connecting 2-phenoxyaniline and naphthaldehyde units through a nitrogen bridge (Figure 1). Rings A(C1—C6), B(C7—C12) and C(C14—C23) are planar and the dihedral angles between them are A/B=77.41 (17)°, A/C=79.24 (15)°, B/C=8.29 (15)°. The hydrogen atom in the title compound (I) is located on nitrogen atom, thus the keto-amine tautomer is favored over the phenol-imine form. The presence of keto form can be also confirmed by N1—C13 and C15—O1 bond lengths. The C15—O1 bond length of 1.276 (7)Å indicates double-bond character while the N1—C13 bond length of 1.315 (6)Å indicates single-bond character. Similar results are also reported in the literature (Özek et al., 2004; Takano et al., 2009]. Intermolecular weak C—H···π ring interactions are also present in the crystal structure (Figure 2). Details of C—H···π contacts are given in Table 1.

Experimental

(E)-1-((2-phenoxyphenylamino)methyl)naphthalen-2-ol was prepared by refluxing a mixture of a solution containing 2-hydroxy-1-naphthaldehyde (17.2 mg, 0.1 mmol) in ethanol (30 ml) and a solution containing 2-phenoxyaniline (18.5 mg, 0.1 mmol) in ethanol (20 ml). The reaction mixture was stirred for 1 h. under reflux. Single crystals of the title compound for x-ray analysis were obtained by slow evaporation of an ethanol solution (Yield 68%; m.p. 411-413 K ).

Refinement

H atoms attached to carbon atoms were placed in calculated positions with Uiso(H) = 1.2Ueq(C). The coordinates of the amine hydrogen obtained from a difference map and refined isotropically with N—H = 0.86Å constrain.

Figures

Fig. 1.
The molecular structure of (I), showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 40% probability.
Fig. 2.
The packing of (I), showing weak C—H···π ring interactions with dashed lines.

Crystal data

C23H17NO2F(000) = 1424
Mr = 339.38Dx = 1.309 Mg m3
Monoclinic, C2/cMelting point = 411–413 K
Hall symbol: -C 2ycMo Kα radiation, λ = 0.71073 Å
a = 14.6428 (11) ÅCell parameters from 2565 reflections
b = 5.6297 (3) Åθ = 2.8–24.1°
c = 42.602 (3) ŵ = 0.08 mm1
β = 101.175 (6)°T = 296 K
V = 3445.3 (4) Å3Long prismatic rod, yellow
Z = 80.40 × 0.34 × 0.23 mm

Data collection

Stoe IPDSII diffractometer2565 independent reflections
Radiation source: fine-focus sealed tube1522 reflections with I > 2σ(I)
plane graphiteRint = 0.212
Detector resolution: 6.67 pixels mm-1θmax = 23.6°, θmin = 2.8°
rotation scansh = −16→16
Absorption correction: integration (X-RED; Stoe & Cie, 2002)k = −6→6
Tmin = 0.960, Tmax = 0.996l = −47→47
11832 measured reflections

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.115H-atom parameters constrained
wR(F2) = 0.331w = 1/[σ2(Fo2) + (0.1935P)2] where P = (Fo2 + 2Fc2)/3
S = 1.06(Δ/σ)max = 0.001
2565 reflectionsΔρmax = 0.30 e Å3
236 parametersΔρmin = −0.39 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0045 (17)

Special details

Experimental. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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)

xyzUiso*/Ueq
C10.4850 (4)−0.3268 (11)0.56310 (14)0.0576 (16)
C20.4649 (5)−0.1907 (13)0.53616 (18)0.0748 (19)
H20.4969−0.04990.53450.090*
C30.3949 (5)−0.2683 (15)0.51107 (16)0.082 (2)
H30.3797−0.18000.49230.099*
C40.3489 (4)−0.4759 (13)0.51444 (17)0.075 (2)
H40.3040−0.53140.49760.090*
C50.3683 (4)−0.6017 (12)0.54216 (17)0.0704 (19)
H50.3345−0.73830.54450.084*
C60.4377 (4)−0.5276 (11)0.56682 (15)0.0641 (18)
H60.4517−0.61440.58570.077*
C70.6418 (3)−0.3294 (10)0.59332 (14)0.0513 (14)
C80.7060 (3)−0.2112 (10)0.61624 (13)0.0482 (14)
C90.7982 (4)−0.2933 (11)0.62192 (15)0.0581 (16)
H90.8429−0.21580.63690.070*
C100.8231 (4)−0.4821 (11)0.60609 (16)0.0622 (17)
H100.8845−0.53430.61060.075*
C110.7588 (4)−0.5997 (11)0.58329 (15)0.0627 (17)
H110.7767−0.72840.57220.075*
C120.6665 (4)−0.5216 (12)0.57725 (15)0.0639 (18)
H120.6220−0.60020.56230.077*
C130.7229 (4)0.1281 (10)0.65264 (13)0.0503 (14)
H130.78720.10900.65710.060*
C140.6860 (4)0.3109 (9)0.66784 (13)0.0487 (14)
C150.5865 (4)0.3495 (10)0.66058 (15)0.0571 (16)
C160.5513 (4)0.5463 (12)0.67467 (18)0.0716 (19)
H160.48760.57470.66990.086*
C170.6065 (4)0.6971 (12)0.69492 (18)0.0704 (19)
H170.57970.82350.70390.084*
C180.7048 (4)0.6642 (10)0.70262 (14)0.0548 (15)
C190.7619 (5)0.8288 (11)0.72230 (14)0.0647 (17)
H190.73470.95660.73080.078*
C200.8549 (5)0.8045 (12)0.72899 (16)0.0730 (19)
H200.89160.91370.74220.088*
C210.8956 (5)0.6163 (13)0.71618 (17)0.078 (2)
H210.95990.59760.72130.094*
C220.8435 (4)0.4567 (12)0.69608 (16)0.0691 (19)
H220.87280.33520.68700.083*
C230.7448 (4)0.4752 (9)0.68896 (12)0.0481 (14)
N10.6738 (3)−0.0213 (8)0.63234 (10)0.0493 (12)
H10.61460.00050.62850.059*
O10.5318 (2)0.2158 (8)0.64128 (11)0.0720 (14)
O20.5522 (2)−0.2386 (8)0.58887 (11)0.0755 (15)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C10.031 (3)0.080 (4)0.055 (4)0.002 (3)−0.008 (3)−0.025 (3)
C20.060 (4)0.084 (4)0.075 (5)−0.016 (3)−0.001 (3)−0.005 (4)
C30.072 (5)0.116 (6)0.050 (4)−0.011 (4)−0.010 (3)0.007 (4)
C40.044 (3)0.098 (5)0.072 (5)−0.011 (3)−0.014 (3)−0.016 (4)
C50.045 (3)0.084 (4)0.075 (5)−0.010 (3)−0.005 (3)−0.007 (4)
C60.049 (3)0.074 (4)0.060 (4)0.001 (3)−0.013 (3)−0.002 (3)
C70.028 (3)0.066 (3)0.055 (3)0.000 (2)−0.003 (2)−0.011 (3)
C80.033 (3)0.068 (3)0.042 (3)−0.005 (2)0.003 (2)−0.006 (3)
C90.031 (3)0.075 (4)0.062 (4)−0.010 (3)−0.007 (3)0.001 (3)
C100.032 (3)0.077 (4)0.074 (4)−0.003 (3)0.003 (3)−0.008 (3)
C110.043 (3)0.080 (4)0.064 (4)0.001 (3)0.008 (3)−0.014 (3)
C120.033 (3)0.093 (4)0.061 (4)−0.007 (3)−0.002 (3)−0.022 (3)
C130.033 (3)0.071 (3)0.043 (3)0.000 (3)−0.003 (2)−0.001 (3)
C140.034 (3)0.062 (3)0.046 (3)−0.003 (2)−0.003 (2)0.001 (3)
C150.029 (3)0.069 (4)0.069 (4)−0.003 (3)0.000 (3)−0.001 (3)
C160.034 (3)0.090 (5)0.088 (5)0.006 (3)0.004 (3)−0.012 (4)
C170.048 (3)0.080 (4)0.083 (5)0.014 (3)0.012 (3)−0.004 (4)
C180.049 (3)0.061 (3)0.050 (3)0.004 (3)0.000 (3)0.000 (3)
C190.073 (4)0.065 (4)0.050 (3)0.008 (3)−0.001 (3)−0.008 (3)
C200.070 (4)0.082 (4)0.060 (4)−0.009 (4)−0.005 (3)−0.013 (3)
C210.045 (3)0.106 (5)0.075 (5)−0.004 (3)−0.007 (3)−0.021 (4)
C220.038 (3)0.093 (4)0.070 (4)0.003 (3)−0.007 (3)−0.034 (3)
C230.041 (3)0.058 (3)0.040 (3)0.003 (2)−0.004 (2)0.002 (2)
N10.027 (2)0.071 (3)0.045 (3)−0.006 (2)−0.0059 (19)−0.006 (2)
O10.0240 (19)0.097 (3)0.087 (3)−0.0049 (19)−0.009 (2)−0.018 (3)
O20.028 (2)0.106 (3)0.083 (3)0.004 (2)−0.013 (2)−0.047 (3)

Geometric parameters (Å, °)

C1—C61.351 (9)C12—H120.9300
C1—C21.364 (9)C13—N11.315 (6)
C1—O21.414 (6)C13—C141.381 (8)
C2—C31.400 (9)C13—H130.9300
C2—H20.9300C14—C151.447 (7)
C3—C41.370 (10)C14—C231.451 (7)
C3—H30.9300C15—O11.276 (7)
C4—C51.359 (10)C15—C161.404 (9)
C4—H40.9300C16—C171.359 (9)
C5—C61.377 (8)C16—H160.9300
C5—H50.9300C17—C181.425 (8)
C6—H60.9300C17—H170.9300
C7—C121.366 (8)C18—C231.395 (8)
C7—O21.387 (6)C18—C191.411 (8)
C7—C81.387 (7)C19—C201.344 (10)
C8—N11.400 (7)C19—H190.9300
C8—C91.403 (8)C20—C211.379 (10)
C9—C101.347 (9)C20—H200.9300
C9—H90.9300C21—C221.368 (8)
C10—C111.383 (8)C21—H210.9300
C10—H100.9300C22—C231.422 (8)
C11—C121.397 (8)C22—H220.9300
C11—H110.9300N1—H10.8600
C6—C1—C2122.4 (5)N1—C13—H13117.6
C6—C1—O2119.9 (6)C14—C13—H13117.6
C2—C1—O2117.4 (6)C13—C14—C15118.8 (5)
C1—C2—C3118.3 (7)C13—C14—C23121.8 (5)
C1—C2—H2120.9C15—C14—C23119.3 (5)
C3—C2—H2120.9O1—C15—C16120.3 (5)
C4—C3—C2119.2 (7)O1—C15—C14122.0 (5)
C4—C3—H3120.4C16—C15—C14117.7 (5)
C2—C3—H3120.4C17—C16—C15122.9 (5)
C5—C4—C3120.8 (6)C17—C16—H16118.6
C5—C4—H4119.6C15—C16—H16118.6
C3—C4—H4119.6C16—C17—C18120.9 (6)
C4—C5—C6120.3 (6)C16—C17—H17119.5
C4—C5—H5119.9C18—C17—H17119.5
C6—C5—H5119.9C23—C18—C19120.0 (5)
C1—C6—C5118.9 (6)C23—C18—C17119.4 (5)
C1—C6—H6120.5C19—C18—C17120.5 (6)
C5—C6—H6120.5C20—C19—C18121.3 (6)
C12—C7—O2124.0 (5)C20—C19—H19119.4
C12—C7—C8121.5 (5)C18—C19—H19119.4
O2—C7—C8114.4 (5)C19—C20—C21119.5 (6)
C7—C8—N1117.7 (5)C19—C20—H20120.2
C7—C8—C9117.5 (5)C21—C20—H20120.2
N1—C8—C9124.8 (5)C22—C21—C20121.4 (6)
C10—C9—C8121.3 (5)C22—C21—H21119.3
C10—C9—H9119.4C20—C21—H21119.3
C8—C9—H9119.4C21—C22—C23120.4 (6)
C9—C10—C11121.0 (6)C21—C22—H22119.8
C9—C10—H10119.5C23—C22—H22119.8
C11—C10—H10119.5C18—C23—C22117.3 (5)
C10—C11—C12118.8 (6)C18—C23—C14119.9 (5)
C10—C11—H11120.6C22—C23—C14122.8 (5)
C12—C11—H11120.6C13—N1—C8128.1 (4)
C7—C12—C11119.9 (5)C13—N1—H1115.9
C7—C12—H12120.1C8—N1—H1115.9
C11—C12—H12120.1C7—O2—C1118.3 (4)
N1—C13—C14124.8 (5)
C6—C1—C2—C3−2.5 (11)C14—C15—C16—C17−1.0 (11)
O2—C1—C2—C3−176.5 (6)C15—C16—C17—C181.0 (11)
C1—C2—C3—C40.3 (11)C16—C17—C18—C230.4 (10)
C2—C3—C4—C52.4 (12)C16—C17—C18—C19176.6 (7)
C3—C4—C5—C6−3.0 (11)C23—C18—C19—C20−1.8 (10)
C2—C1—C6—C51.9 (10)C17—C18—C19—C20−177.9 (7)
O2—C1—C6—C5175.7 (6)C18—C19—C20—C210.6 (11)
C4—C5—C6—C10.9 (10)C19—C20—C21—C221.7 (12)
C12—C7—C8—N1−177.8 (5)C20—C21—C22—C23−2.7 (12)
O2—C7—C8—N11.2 (8)C19—C18—C23—C220.7 (9)
C12—C7—C8—C91.2 (9)C17—C18—C23—C22176.9 (6)
O2—C7—C8—C9−179.8 (5)C19—C18—C23—C14−177.9 (5)
C7—C8—C9—C10−1.0 (9)C17—C18—C23—C14−1.7 (9)
N1—C8—C9—C10177.9 (6)C21—C22—C23—C181.5 (10)
C8—C9—C10—C111.0 (10)C21—C22—C23—C14−180.0 (6)
C9—C10—C11—C12−1.1 (10)C13—C14—C23—C18176.9 (5)
O2—C7—C12—C11179.8 (6)C15—C14—C23—C181.6 (8)
C8—C7—C12—C11−1.4 (10)C13—C14—C23—C22−1.6 (9)
C10—C11—C12—C71.3 (10)C15—C14—C23—C22−176.9 (6)
N1—C13—C14—C15−2.0 (9)C14—C13—N1—C8−179.5 (5)
N1—C13—C14—C23−177.4 (5)C7—C8—N1—C13−173.3 (5)
C13—C14—C15—O12.0 (9)C9—C8—N1—C137.7 (9)
C23—C14—C15—O1177.4 (6)C12—C7—O2—C1−9.5 (10)
C13—C14—C15—C16−175.8 (6)C8—C7—O2—C1171.6 (6)
C23—C14—C15—C16−0.3 (9)C6—C1—O2—C784.9 (8)
O1—C15—C16—C17−178.8 (7)C2—C1—O2—C7−101.0 (7)

Hydrogen-bond geometry (Å, °)

Cg1 and Cg2 are the centroids of the C1–C6 and C18–C23 rings, respectively.
D—H···AD—HH···AD···AD—H···A
N1—H1···O10.861.872.561 (6)136
C11—H11···Cg1i0.932.873.664 (7)144
C19—H19···Cg2ii0.932.903.674 (7)142

Symmetry codes: (i) x+1/2, y−1/2, z; (ii) −x+3/2, y+1/2, −z+3/2.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: SI2256).

References

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