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

Zhao, Y.-F.; Xiong, J.-P.; Zuo, Y.

doi:10.1107/S1600536809020224

organic compounds

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ISSN: 2056-9890

Volume 65| Part 7| July 2009| Page o1477

doi:10.1107/S1600536809020224

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

Yong-Feng Zhao,^a Jin-Ping Xiong ^a ^* and Yu Zuo ^a

^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. π–π 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 ); 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

Crystal data

C₁₈H₁₂N₂O
M_r = 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 ) T_min = 0.976, T_max = 0.983
6177 measured reflections
2628 independent reflections
1146 reflections with I > 2σ(I)
R_int = 0.061

Refinement

R[F² > 2σ(F²)] = 0.067
wR(F²) = 0.195
S = 0.94
2628 reflections
190 parameters
H-atom parameters constrained
Δρ_max = 0.23 e Å⁻³
Δρ_min = −0.24 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	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); cell refinement: CrystalClear; data reduction: CrystalClear; 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 and PLATON.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809020224/hk2700sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809020224/hk2700Isup2.hkl

checkCIF report

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 π–π 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.

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

	Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Hydrogen bond is shown as dashed line.
	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

C₁₈H₁₂N₂O	Z = 2
M_r = 272.30	F(000) = 284
Triclinic, P1	D_x = 1.345 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.8943 (16) Å	Cell parameters from 4320 reflections
b = 9.1356 (18) Å	θ = 3.2–27.5°
c = 9.4933 (19) Å	µ = 0.09 mm⁻¹
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 tube	1146 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.061
Detector resolution: 13.6612 pixels mm^-1	θ_max = 26.0°, θ_min = 3.2°
ω scans	h = −9→9
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005)	k = −11→11
T_min = 0.976, T_max = 0.983	l = −11→11
6177 measured reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.067	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.195	H-atom parameters constrained
S = 0.94	w = 1/[σ²(F_o²) + (0.0919P)²] where P = (F_o² + 2F_c²)/3
2628 reflections	(Δ/σ)_max = 0.016
190 parameters	Δρ_max = 0.23 e Å⁻³
0 restraints	Δρ_min = −0.24 e Å⁻³

Crystal data top

C₁₈H₁₂N₂O	γ = 82.50 (3)°
M_r = 272.30	V = 672.6 (2) Å³
Triclinic, P1	Z = 2
a = 7.8943 (16) Å	Mo Kα radiation
b = 9.1356 (18) Å	µ = 0.09 mm⁻¹
c = 9.4933 (19) Å	T = 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)
T_min = 0.976, T_max = 0.983	R_int = 0.061
6177 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.067	0 restraints
wR(F²) = 0.195	H-atom parameters constrained
S = 0.94	Δρ_max = 0.23 e Å⁻³
2628 reflections	Δρ_min = −0.24 e Å⁻³
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

	x	y	z	U_iso*/U_eq
O1	0.9002 (3)	0.6505 (3)	0.2062 (2)	0.0608 (8)
N1	0.7833 (3)	0.3998 (3)	0.2569 (3)	0.0439 (7)
H1A	0.8270	0.4652	0.1974	0.053*
N2	0.4237 (5)	−0.1364 (4)	0.3557 (4)	0.0852 (12)
C1	0.7515 (4)	0.2689 (4)	0.2031 (3)	0.0421 (8)
C2	0.6494 (4)	0.1697 (3)	0.2774 (3)	0.0452 (9)
H2A	0.5984	0.1876	0.3675	0.054*
C3	0.6234 (4)	0.0444 (4)	0.2177 (4)	0.0482 (9)
C4	0.6973 (5)	0.0157 (4)	0.0832 (4)	0.0609 (11)
H4A	0.6799	−0.0695	0.0437	0.073*
C5	0.7971 (5)	0.1160 (4)	0.0093 (4)	0.0654 (11)
H5A	0.8467	0.0985	−0.0812	0.079*
C6	0.8240 (4)	0.2410 (4)	0.0675 (3)	0.0514 (10)
H6A	0.8914	0.3077	0.0160	0.062*
C7	0.5115 (5)	−0.0569 (4)	0.2954 (4)	0.0611 (11)
C8	0.7525 (4)	0.4310 (3)	0.3886 (3)	0.0408 (8)
H8A	0.7016	0.3630	0.4536	0.049*
C9	0.7916 (4)	0.5615 (3)	0.4381 (3)	0.0405 (8)
C10	0.8725 (4)	0.6662 (3)	0.3400 (4)	0.0433 (9)
C11	0.9241 (5)	0.7903 (4)	0.3945 (4)	0.0576 (11)
H11A	0.9789	0.8582	0.3323	0.069*
C12	0.8969 (5)	0.8139 (4)	0.5334 (4)	0.0577 (10)
H12A	0.9334	0.8968	0.5645	0.069*
C13	0.8122 (4)	0.7125 (3)	0.6335 (4)	0.0424 (9)
C14	0.7876 (4)	0.7374 (4)	0.7790 (4)	0.0533 (10)
H14A	0.8261	0.8199	0.8091	0.064*
C15	0.7077 (4)	0.6415 (4)	0.8761 (4)	0.0554 (10)
H15A	0.6908	0.6590	0.9715	0.067*
C16	0.6524 (4)	0.5185 (4)	0.8304 (4)	0.0509 (9)
H16A	0.5981	0.4529	0.8957	0.061*
C17	0.6766 (4)	0.4920 (4)	0.6902 (3)	0.0483 (9)
H17A	0.6374	0.4087	0.6623	0.058*
C18	0.7585 (4)	0.5863 (3)	0.5875 (3)	0.0367 (8)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.083 (2)	0.0657 (17)	0.0347 (15)	−0.0255 (14)	0.0047 (13)	0.0010 (12)
N1	0.0520 (19)	0.0430 (17)	0.0370 (17)	−0.0146 (13)	0.0051 (13)	−0.0025 (14)
N2	0.120 (3)	0.064 (2)	0.076 (3)	−0.043 (2)	0.011 (2)	−0.010 (2)
C1	0.043 (2)	0.044 (2)	0.040 (2)	−0.0072 (16)	−0.0024 (16)	−0.0059 (17)
C2	0.057 (2)	0.044 (2)	0.035 (2)	−0.0102 (18)	0.0011 (16)	−0.0075 (16)
C3	0.057 (2)	0.042 (2)	0.048 (2)	−0.0068 (18)	−0.0062 (18)	−0.0107 (17)
C4	0.079 (3)	0.055 (2)	0.051 (3)	−0.008 (2)	−0.004 (2)	−0.018 (2)
C5	0.083 (3)	0.069 (3)	0.047 (2)	−0.018 (2)	0.010 (2)	−0.020 (2)
C6	0.053 (2)	0.061 (2)	0.040 (2)	−0.0129 (19)	0.0046 (17)	−0.0033 (18)
C7	0.080 (3)	0.051 (2)	0.054 (3)	−0.014 (2)	−0.001 (2)	−0.011 (2)
C8	0.040 (2)	0.044 (2)	0.038 (2)	−0.0066 (16)	0.0015 (15)	−0.0029 (16)
C9	0.039 (2)	0.041 (2)	0.041 (2)	−0.0065 (16)	−0.0007 (15)	0.0003 (16)
C10	0.052 (2)	0.0366 (19)	0.042 (2)	−0.0093 (16)	−0.0054 (17)	−0.0010 (16)
C11	0.070 (3)	0.047 (2)	0.058 (3)	−0.0253 (19)	−0.001 (2)	0.003 (2)
C12	0.068 (3)	0.050 (2)	0.060 (3)	−0.022 (2)	−0.003 (2)	−0.007 (2)
C13	0.041 (2)	0.042 (2)	0.046 (2)	−0.0029 (16)	−0.0066 (16)	−0.0074 (17)
C14	0.053 (2)	0.055 (2)	0.056 (3)	−0.0066 (19)	−0.0103 (19)	−0.020 (2)
C15	0.058 (2)	0.064 (3)	0.043 (2)	−0.003 (2)	0.0004 (18)	−0.009 (2)
C16	0.057 (2)	0.051 (2)	0.043 (2)	−0.0085 (18)	0.0046 (17)	−0.0013 (18)
C17	0.052 (2)	0.045 (2)	0.048 (2)	−0.0097 (18)	0.0029 (17)	−0.0074 (18)
C18	0.0366 (19)	0.0372 (19)	0.0377 (19)	−0.0076 (15)	−0.0012 (14)	−0.0074 (15)

Geometric parameters (Å, º) top

O1—C10	1.287 (4)	C9—C10	1.431 (4)
N1—C1	1.409 (4)	C9—C18	1.453 (4)
N1—C8	1.304 (4)	C11—C10	1.416 (4)
N1—H1A	0.8600	C11—C12	1.350 (5)
N2—C7	1.142 (4)	C11—H11A	0.9300
C2—C1	1.384 (4)	C12—H12A	0.9300
C2—C3	1.376 (4)	C13—C12	1.435 (4)
C2—H2A	0.9300	C13—C14	1.414 (4)
C4—C3	1.387 (5)	C13—C18	1.403 (4)
C4—C5	1.377 (5)	C14—H14A	0.9300
C4—H4A	0.9300	C15—C14	1.370 (4)
C5—H5A	0.9300	C15—C16	1.382 (5)
C6—C1	1.392 (4)	C15—H15A	0.9300
C6—C5	1.369 (5)	C16—H16A	0.9300
C6—H6A	0.9300	C17—C16	1.369 (4)
C7—C3	1.458 (5)	C17—C18	1.399 (4)
C8—H8A	0.9300	C17—H17A	0.9300
C9—C8	1.406 (4)

C1—N1—H1A	117.0	O1—C10—C9	122.5 (3)
C8—N1—C1	126.0 (3)	O1—C10—C11	119.7 (3)
C8—N1—H1A	117.0	C11—C10—C9	117.8 (3)
C2—C1—N1	123.1 (3)	C10—C11—H11A	118.7
C2—C1—C6	119.0 (3)	C12—C11—C10	122.6 (3)
C6—C1—N1	117.9 (3)	C12—C11—H11A	118.7
C1—C2—H2A	120.1	C11—C12—C13	120.8 (3)
C3—C2—C1	119.8 (3)	C11—C12—H12A	119.6
C3—C2—H2A	120.1	C13—C12—H12A	119.6
C2—C3—C4	121.1 (3)	C14—C13—C12	120.0 (3)
C2—C3—C7	119.2 (3)	C18—C13—C12	119.9 (3)
C4—C3—C7	119.6 (3)	C18—C13—C14	120.0 (3)
C3—C4—H4A	120.7	C13—C14—H14A	119.6
C5—C4—C3	118.6 (4)	C15—C14—C13	120.8 (3)
C5—C4—H4A	120.7	C15—C14—H14A	119.6
C4—C5—H5A	119.6	C14—C15—C16	119.1 (3)
C6—C5—C4	120.9 (4)	C14—C15—H15A	120.5
C6—C5—H5A	119.6	C16—C15—H15A	120.5
C1—C6—H6A	119.7	C15—C16—H16A	119.6
C5—C6—C1	120.5 (3)	C17—C16—C15	120.8 (3)
C5—C6—H6A	119.7	C17—C16—H16A	119.6
N2—C7—C3	179.7 (4)	C16—C17—C18	122.1 (3)
N1—C8—C9	123.9 (3)	C16—C17—H17A	119.0
N1—C8—H8A	118.0	C18—C17—H17A	119.0
C9—C8—H8A	118.0	C13—C18—C9	118.5 (3)
C8—C9—C10	118.8 (3)	C17—C18—C13	117.1 (3)
C8—C9—C18	120.7 (3)	C17—C18—C9	124.4 (3)
C10—C9—C18	120.4 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	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.

Experimental details

Crystal data
Chemical formula	C₁₈H₁₂N₂O
M_r	272.30
Crystal system, space group	Triclinic, 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)
V (Å³)	672.6 (2)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.20 × 0.20 × 0.20

Data collection
Diffractometer	Rigaku SCXmini diffractometer
Absorption correction	Multi-scan (CrystalClear; Rigaku, 2005)
T_min, T_max	0.976, 0.983
No. of measured, independent and observed [I > 2σ(I)] reflections	6177, 2628, 1146
R_int	0.061
(sin θ/λ)_max (Å⁻¹)	0.617

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.067, 0.195, 0.94
No. of reflections	2628
No. of parameters	190
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	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···A	D—H	H···A	D···A	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.

References

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Volume 65| Part 7| July 2009| Page o1477

doi:10.1107/S1600536809020224

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