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ISSN: 2056-9890

(Z)-1-[(3-Cyano­phen­yl)iminiometh­yl]-2-naphtholate

aCollege of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
*Correspondence e-mail: 2007080083@grad.buct.edu.cn

(Received 23 May 2009; accepted 27 May 2009; online 6 June 2009)

The title compound, C18H12N2O, crystallizes in a zwitterionic form. The dihedral angle between the planes of the benzene ring and naphthalene ring system is 13.95 (5)°. An intra­molecular N—H⋯O inter­action results in the formation of a planar six-membered ring, which is oriented at dihedral angles of 13.50 (4) and 4.49 (4)° with respect to the benzene ring and naphthalene ring system, respectively. In the crystal structure, inter­molecular C—H⋯O and C—H⋯N inter­actions link the mol­ecules into a two-dimensional network. ππ contacts between the naphthalene systems [centroid–centroid distance = 3.974 (1) Å] may further stabilize the structure.

Related literature

For the pharmacological activity of Schiff base compounds, see: Dao et al. (2000[Dao, V.-T., Gaspard, C., Mayer, M., Werner, G. H., Nguyen, S. N. & Michelot, R. J. (2000). Eur. J. Med. Chem. 35, 805-813.]); Sriram et al. (2006[Sriram, D., Yogeeswari, P., Myneedu, N. S. & Saraswat, V. (2006). Bioorg. Med. Chem. Lett. 16, 2127-2129.]). For the role played by Schiff base compounds in coordination chemistry related to magnetism, see: Chen et al. (2008[Chen, Z. H., Morimoto, H., Matsunaga, S. & Shibasaki, M. (2008). J. Am. Chem. Soc. 130, 2170-2171.]); Weber et al. (2007[Weber, B., Tandon, R. & Himsl, D. (2007). Z. Anorg. Allg. Chem. 633, 1159-1162.]). For related structures, see: Elmali et al. (2001[Elmali, A., Elerman, Y. & Svoboda, I. (2001). Acta Cryst. C57, 485-486.]); Yüce et al. (2006[Yüce, S., Albayrak, Ç., Odabaşoğlu, M. & Büyükgüngör, O. (2006). Acta Cryst. C62, o389-o393.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]).

[Scheme 1]

Experimental

Crystal data
  • C18H12N2O

  • Mr = 272.30

  • Triclinic, [P \overline 1]

  • a = 7.8943 (16) Å

  • b = 9.1356 (18) Å

  • c = 9.4933 (19) Å

  • α = 83.97 (3)°

  • β = 84.41 (3)°

  • γ = 82.50 (3)°

  • V = 672.6 (2) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 294 K

  • 0.20 × 0.20 × 0.20 mm

Data collection
  • Rigaku SCXmini diffractometer

  • Absorption correction: multi-scan (CrystalClear; Rigaku, 2005[Rigaku (2005). CrystalClear. Rigaku Corporation, Tokyo, Japan.]) Tmin = 0.976, Tmax = 0.983

  • 6177 measured reflections

  • 2628 independent reflections

  • 1146 reflections with I > 2σ(I)

  • Rint = 0.061

Refinement
  • R[F2 > 2σ(F2)] = 0.067

  • wR(F2) = 0.195

  • S = 0.94

  • 2628 reflections

  • 190 parameters

  • H-atom parameters constrained

  • Δρmax = 0.23 e Å−3

  • Δρmin = −0.24 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1A⋯O1 0.86 1.87 2.562 (3) 136
C2—H2A⋯N2i 0.93 2.61 3.463 (3) 152
C6—H6A⋯O1ii 0.93 2.57 3.376 (3) 145
C17—H17A⋯N2i 0.93 2.62 3.522 (3) 163
Symmetry codes: (i) -x+1, -y, -z+1; (ii) -x+2, -y+1, -z.

Data collection: CrystalClear (Rigaku, 2005[Rigaku (2005). CrystalClear. Rigaku Corporation, Tokyo, Japan.]); cell refinement: CrystalClear; data reduction: CrystalClear; 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: SHELXL97 and PLATON.

Supporting information


Comment top

Schiff base compounds have received considerable attention for many years, primarily due to various pharmacological activities, such as anticancer (Dao et al., 2000) and anti-HIV (Sriram et al., 2006) activities. In addition, Schiff base compounds play important roles in coordination chemistry related to magnetism (Weber et al., 2007) and catalysis (Chen et al., 2008). Generally, Schiff base compounds exhibit the phenol-imine and keto-amine forms. Another form of the Schiff base compounds is their zwitterionic form, and this form have been reported in the literature (Elmali, et al., 2001). We report herein the crystal structure of the title compound.

The molecule of the title compound (Fig 1) is in a zwitterionic form. The bond lengths (Allen et al., 1987) and angles are within normal ranges, and C8=N1 [1.304 (4) Å] and C10-O1 [1.287 (4) Å] bonds may be compared with the corresponding values [1.2954 (19) and 1.2946 (17) Å] in a similar zwitterionic structure (Yüce et al., 2006). Phenyl and naphthalyl rings, A (C1-C6) and B (C9-C18), are, of course, planar and the dihedral angle between them is 13.95 (5)°. Intramolecular N-H···O interaction (Table 1) results in the formation of a planar six-membered ring C (O1/N1/C8-C10/H1A), which is oriented with respect to rings A and B at dihedral angles of 13.50 (4) and 4.49 (4) °, respectively.

In the crystal structure, intramolecular N-H···O and intermolecular C-H···O and C-H···N interactions (Table 1) link the molecules into a two-dimensional network (Fig. 2), in which they may be effective in the stabilization of the structure. The ππ contact between the naphthalyl rings, Cg2—Cg2i [symmetry code: (i) -x, 1 - y, 1 - z, where Cg2 is centroid of the ring (C9-C13/C18)] may further stabilize the structure, with centroid-centroid distance of 3.974 (1) Å.

Related literature top

For the pharmacological activity of Schiff base compounds, see: Dao et al. (2000); Sriram et al. (2006). For the role played by Schiff base compounds in coordination chemistry related to magnetism, see: Chen et al. (2008); Weber et al. (2007). For related structures, see: Elmali et al. (2001); Yüce et al. (2006). For bond-length data, see: Allen et al. (1987).

Experimental top

For the preparation of the title compound, 3-aminobenzonitrile (0.59 g, 5 mmol) and 2-hydroxynaphthalene-1-carbaldehyde (0.861 g, 5 mmol) were dissolved in ethanol (25 ml). The resulting mixture was heated to reflux for 6 h, and then cooled to room temperature. The solid product was collected by filtration. Crystals suitable for X-ray analysis were obtained on slow evaporation at room temperature.

Refinement top

H atoms were positioned geometrically, with N-H = 0.86 Å (for NH) and C-H = 0.93 Å for aromatic H and constrained to ride on their parent atoms, with Uiso(H) = 1.2Ueq(C,N).

Computing details top

Data collection: CrystalClear (Rigaku, 2005); cell refinement: CrystalClear (Rigaku, 2005); data reduction: CrystalClear (Rigaku, 2005); 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: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Hydrogen bond is shown as dashed line.
[Figure 2] Fig. 2. A partial packing diagram of the title compound. Hydrogen bonds are shown as dashed lines.
(Z)-1-[(3-Cyanophenyl)iminiomethyl]-2-naphtholate top
Crystal data top
C18H12N2OZ = 2
Mr = 272.30F(000) = 284
Triclinic, P1Dx = 1.345 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.8943 (16) ÅCell parameters from 4320 reflections
b = 9.1356 (18) Åθ = 3.2–27.5°
c = 9.4933 (19) ŵ = 0.09 mm1
α = 83.97 (3)°T = 294 K
β = 84.41 (3)°Prism, yellow
γ = 82.50 (3)°0.20 × 0.20 × 0.20 mm
V = 672.6 (2) Å3
Data collection top
Rigaku SCXmini
diffractometer
2628 independent reflections
Radiation source: fine-focus sealed tube1146 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.061
Detector resolution: 13.6612 pixels mm-1θmax = 26.0°, θmin = 3.2°
ω scansh = 99
Absorption correction: multi-scan
(CrystalClear; Rigaku, 2005)
k = 1111
Tmin = 0.976, Tmax = 0.983l = 1111
6177 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)] = 0.067Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.195H-atom parameters constrained
S = 0.94 w = 1/[σ2(Fo2) + (0.0919P)2]
where P = (Fo2 + 2Fc2)/3
2628 reflections(Δ/σ)max = 0.016
190 parametersΔρmax = 0.23 e Å3
0 restraintsΔρmin = 0.24 e Å3
Crystal data top
C18H12N2Oγ = 82.50 (3)°
Mr = 272.30V = 672.6 (2) Å3
Triclinic, P1Z = 2
a = 7.8943 (16) ÅMo Kα radiation
b = 9.1356 (18) ŵ = 0.09 mm1
c = 9.4933 (19) ÅT = 294 K
α = 83.97 (3)°0.20 × 0.20 × 0.20 mm
β = 84.41 (3)°
Data collection top
Rigaku SCXmini
diffractometer
2628 independent reflections
Absorption correction: multi-scan
(CrystalClear; Rigaku, 2005)
1146 reflections with I > 2σ(I)
Tmin = 0.976, Tmax = 0.983Rint = 0.061
6177 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0670 restraints
wR(F2) = 0.195H-atom parameters constrained
S = 0.94Δρmax = 0.23 e Å3
2628 reflectionsΔρmin = 0.24 e Å3
190 parameters
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
O10.9002 (3)0.6505 (3)0.2062 (2)0.0608 (8)
N10.7833 (3)0.3998 (3)0.2569 (3)0.0439 (7)
H1A0.82700.46520.19740.053*
N20.4237 (5)0.1364 (4)0.3557 (4)0.0852 (12)
C10.7515 (4)0.2689 (4)0.2031 (3)0.0421 (8)
C20.6494 (4)0.1697 (3)0.2774 (3)0.0452 (9)
H2A0.59840.18760.36750.054*
C30.6234 (4)0.0444 (4)0.2177 (4)0.0482 (9)
C40.6973 (5)0.0157 (4)0.0832 (4)0.0609 (11)
H4A0.67990.06950.04370.073*
C50.7971 (5)0.1160 (4)0.0093 (4)0.0654 (11)
H5A0.84670.09850.08120.079*
C60.8240 (4)0.2410 (4)0.0675 (3)0.0514 (10)
H6A0.89140.30770.01600.062*
C70.5115 (5)0.0569 (4)0.2954 (4)0.0611 (11)
C80.7525 (4)0.4310 (3)0.3886 (3)0.0408 (8)
H8A0.70160.36300.45360.049*
C90.7916 (4)0.5615 (3)0.4381 (3)0.0405 (8)
C100.8725 (4)0.6662 (3)0.3400 (4)0.0433 (9)
C110.9241 (5)0.7903 (4)0.3945 (4)0.0576 (11)
H11A0.97890.85820.33230.069*
C120.8969 (5)0.8139 (4)0.5334 (4)0.0577 (10)
H12A0.93340.89680.56450.069*
C130.8122 (4)0.7125 (3)0.6335 (4)0.0424 (9)
C140.7876 (4)0.7374 (4)0.7790 (4)0.0533 (10)
H14A0.82610.81990.80910.064*
C150.7077 (4)0.6415 (4)0.8761 (4)0.0554 (10)
H15A0.69080.65900.97150.067*
C160.6524 (4)0.5185 (4)0.8304 (4)0.0509 (9)
H16A0.59810.45290.89570.061*
C170.6766 (4)0.4920 (4)0.6902 (3)0.0483 (9)
H17A0.63740.40870.66230.058*
C180.7585 (4)0.5863 (3)0.5875 (3)0.0367 (8)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.083 (2)0.0657 (17)0.0347 (15)0.0255 (14)0.0047 (13)0.0010 (12)
N10.0520 (19)0.0430 (17)0.0370 (17)0.0146 (13)0.0051 (13)0.0025 (14)
N20.120 (3)0.064 (2)0.076 (3)0.043 (2)0.011 (2)0.010 (2)
C10.043 (2)0.044 (2)0.040 (2)0.0072 (16)0.0024 (16)0.0059 (17)
C20.057 (2)0.044 (2)0.035 (2)0.0102 (18)0.0011 (16)0.0075 (16)
C30.057 (2)0.042 (2)0.048 (2)0.0068 (18)0.0062 (18)0.0107 (17)
C40.079 (3)0.055 (2)0.051 (3)0.008 (2)0.004 (2)0.018 (2)
C50.083 (3)0.069 (3)0.047 (2)0.018 (2)0.010 (2)0.020 (2)
C60.053 (2)0.061 (2)0.040 (2)0.0129 (19)0.0046 (17)0.0033 (18)
C70.080 (3)0.051 (2)0.054 (3)0.014 (2)0.001 (2)0.011 (2)
C80.040 (2)0.044 (2)0.038 (2)0.0066 (16)0.0015 (15)0.0029 (16)
C90.039 (2)0.041 (2)0.041 (2)0.0065 (16)0.0007 (15)0.0003 (16)
C100.052 (2)0.0366 (19)0.042 (2)0.0093 (16)0.0054 (17)0.0010 (16)
C110.070 (3)0.047 (2)0.058 (3)0.0253 (19)0.001 (2)0.003 (2)
C120.068 (3)0.050 (2)0.060 (3)0.022 (2)0.003 (2)0.007 (2)
C130.041 (2)0.042 (2)0.046 (2)0.0029 (16)0.0066 (16)0.0074 (17)
C140.053 (2)0.055 (2)0.056 (3)0.0066 (19)0.0103 (19)0.020 (2)
C150.058 (2)0.064 (3)0.043 (2)0.003 (2)0.0004 (18)0.009 (2)
C160.057 (2)0.051 (2)0.043 (2)0.0085 (18)0.0046 (17)0.0013 (18)
C170.052 (2)0.045 (2)0.048 (2)0.0097 (18)0.0029 (17)0.0074 (18)
C180.0366 (19)0.0372 (19)0.0377 (19)0.0076 (15)0.0012 (14)0.0074 (15)
Geometric parameters (Å, º) top
O1—C101.287 (4)C9—C101.431 (4)
N1—C11.409 (4)C9—C181.453 (4)
N1—C81.304 (4)C11—C101.416 (4)
N1—H1A0.8600C11—C121.350 (5)
N2—C71.142 (4)C11—H11A0.9300
C2—C11.384 (4)C12—H12A0.9300
C2—C31.376 (4)C13—C121.435 (4)
C2—H2A0.9300C13—C141.414 (4)
C4—C31.387 (5)C13—C181.403 (4)
C4—C51.377 (5)C14—H14A0.9300
C4—H4A0.9300C15—C141.370 (4)
C5—H5A0.9300C15—C161.382 (5)
C6—C11.392 (4)C15—H15A0.9300
C6—C51.369 (5)C16—H16A0.9300
C6—H6A0.9300C17—C161.369 (4)
C7—C31.458 (5)C17—C181.399 (4)
C8—H8A0.9300C17—H17A0.9300
C9—C81.406 (4)
C1—N1—H1A117.0O1—C10—C9122.5 (3)
C8—N1—C1126.0 (3)O1—C10—C11119.7 (3)
C8—N1—H1A117.0C11—C10—C9117.8 (3)
C2—C1—N1123.1 (3)C10—C11—H11A118.7
C2—C1—C6119.0 (3)C12—C11—C10122.6 (3)
C6—C1—N1117.9 (3)C12—C11—H11A118.7
C1—C2—H2A120.1C11—C12—C13120.8 (3)
C3—C2—C1119.8 (3)C11—C12—H12A119.6
C3—C2—H2A120.1C13—C12—H12A119.6
C2—C3—C4121.1 (3)C14—C13—C12120.0 (3)
C2—C3—C7119.2 (3)C18—C13—C12119.9 (3)
C4—C3—C7119.6 (3)C18—C13—C14120.0 (3)
C3—C4—H4A120.7C13—C14—H14A119.6
C5—C4—C3118.6 (4)C15—C14—C13120.8 (3)
C5—C4—H4A120.7C15—C14—H14A119.6
C4—C5—H5A119.6C14—C15—C16119.1 (3)
C6—C5—C4120.9 (4)C14—C15—H15A120.5
C6—C5—H5A119.6C16—C15—H15A120.5
C1—C6—H6A119.7C15—C16—H16A119.6
C5—C6—C1120.5 (3)C17—C16—C15120.8 (3)
C5—C6—H6A119.7C17—C16—H16A119.6
N2—C7—C3179.7 (4)C16—C17—C18122.1 (3)
N1—C8—C9123.9 (3)C16—C17—H17A119.0
N1—C8—H8A118.0C18—C17—H17A119.0
C9—C8—H8A118.0C13—C18—C9118.5 (3)
C8—C9—C10118.8 (3)C17—C18—C13117.1 (3)
C8—C9—C18120.7 (3)C17—C18—C9124.4 (3)
C10—C9—C18120.4 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···O10.861.872.562 (3)136
C2—H2A···N2i0.932.613.463 (3)152
C6—H6A···O1ii0.932.573.376 (3)145
C17—H17A···N2i0.932.623.522 (3)163
Symmetry codes: (i) x+1, y, z+1; (ii) x+2, y+1, z.

Experimental details

Crystal data
Chemical formulaC18H12N2O
Mr272.30
Crystal system, space groupTriclinic, P1
Temperature (K)294
a, b, c (Å)7.8943 (16), 9.1356 (18), 9.4933 (19)
α, β, γ (°)83.97 (3), 84.41 (3), 82.50 (3)
V3)672.6 (2)
Z2
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.20 × 0.20 × 0.20
Data collection
DiffractometerRigaku SCXmini
diffractometer
Absorption correctionMulti-scan
(CrystalClear; Rigaku, 2005)
Tmin, Tmax0.976, 0.983
No. of measured, independent and
observed [I > 2σ(I)] reflections
6177, 2628, 1146
Rint0.061
(sin θ/λ)max1)0.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.067, 0.195, 0.94
No. of reflections2628
No. of parameters190
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.23, 0.24

Computer programs: CrystalClear (Rigaku, 2005), SHELXS97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···O10.861.872.562 (3)136
C2—H2A···N2i0.932.613.463 (3)152
C6—H6A···O1ii0.932.573.376 (3)145
C17—H17A···N2i0.932.623.522 (3)163
Symmetry codes: (i) x+1, y, z+1; (ii) x+2, y+1, z.
 

References

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