2,2′-[Naphthalene-1,5-diylbis(nitrilo­methanylyl­idene)]diphenol

Karthikeyan, S.; Muthukumaran, J.; Krishna, R.; Manimaran, B.

doi:10.1107/S1600536811023099

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 67| Part 7| July 2011| Pages o1765-o1766

doi:10.1107/S1600536811023099

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2,2′-[Naphthalene-1,5-diylbis(nitrilomethanylylidene)]diphenol

S. Karthikeyan,^a J. Muthukumaran,^b R. Krishna ^b ‡ and Bala. Manimaran ^a ^*

^aDepartment of Chemistry, Pondicherry University, Puducherry 605 014, India, and ^bCentre for Bioinformatics, Pondicherry University, Puducherry 605 014, India
^*Correspondence e-mail: manimaran.che@pondiuni.edu.in

(Received 12 June 2011; accepted 14 June 2011; online 22 June 2011)

The title compound, C₂₄H₁₈N₂O₂, lies about an inversion centre and the asymmetric unit contains one half-molecule. An intramolecular O—H⋯N hydrogen bond generates a six-membered ring, producing an S(6) ring motif. The crystal packing exhibits intermolecular π–π stacking interactions between the aromatic rings with a centroid–centroid distance of 3.851 (2) Å.

Related literature

For hydrogen-bond motifs, see: Bernstein et al. (1995 ). For applications of Schiff base ligands, see: Pandeya et al. (1999 , 2000 ); Singh & Dash (1988 ); Kelley et al. (1995 ); Turan-Zitouni et al. (2007 ); Tarafder et al. (2002 ); Sakyan et al. (2004 ); Gianneshi et al. (2005 ); Morris et al. (2001 ); Lu et al. (2007 ); Lau et al. (1999 ). For a related structure, see: Al-Douh et al. (2009 ).

Experimental

Crystal data

C₂₄H₁₈N₂O₂
M_r = 366.40
Monoclinic, P 2₁ /c
a = 3.8510 (9) Å
b = 19.395 (6) Å
c = 11.796 (2) Å
β = 95.85 (3)°
V = 876.4 (4) Å³
Z = 2
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 293 K
0.23 × 0.15 × 0.11 mm

Data collection

Oxford Diffraction Xcalibur-S diffractometer
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009 $[Oxford Diffraction (2009). CrysAlis CCD, CrysAlis RED and CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, England.]$ ) T_min = 0.980, T_max = 0.990
4711 measured reflections
1544 independent reflections
1004 reflections with I > 2σ(I)
R_int = 0.099

Refinement

R[F² > 2σ(F²)] = 0.080
wR(F²) = 0.206
S = 1.18
1544 reflections
128 parameters
H-atom parameters constrained
Δρ_max = 0.35 e Å⁻³
Δρ_min = −0.36 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯N1	0.82	1.90	2.634 (3)	148

Data collection: CrysAlis PRO (Oxford Diffraction, 2009 $[Oxford Diffraction (2009). CrysAlis CCD, CrysAlis RED and CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, England.]$ ); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; 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 ); software used to prepare material for publication: PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811023099/sj5163sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811023099/sj5163Isup2.hkl

checkCIF report

Comment top

Schiff base ligands exhibit several biological and pharmacological properties such as anti-viral, anti-cancer, anti-bacterial, anti-fungal, anti-inflammatory, anti-convulsant and anti-HIV activities (Pandeya et al., 1999, 2000; Singh & Dash, 1988; Kelley et al., 1995; Turan-Zitouni et al., 2007; Tarafder et al., 2002). They are well known to be medicinally important and have been used to design several medicinal compounds (Sakyan et al., 2004). Schiff base ligands have been extensively employed in various fields such as catalysis (Gianneshi et al., 2005), materials chemistry (Morris et al., 2001) and magneto chemistry (Lu et al., 2007). Schiff bases that incorporate an imine group (–CH=N), are used in elucidating the transformation and rasemination mechanism in biological systems (Lau et al., 1999). In view of the growing medicinal importance of Schiff base ligands and their derivatives, a single-crystal X-ray diffraction study on the title compound was carried out and analyzed. The molecular structure of the title compound is shown in Fig. 1. The bond length of imine group (–CH=N) is comparable to those observed in a related crystal structure namely that of 6,6'-Dimethoxy-2,2'-[p-phenylene-bis(nitrilomethylidyne)]diphenol chloroform disolvate (Al-Douh et al., 2009). The atom series and their weighted average absolute torsion angles in all six-membered ring of title compound are Ring 1: C1/C2/C3/C4/C5/C6 & 0.2°, Ring 2: C8/C9/C10/C12/C11a/C8a & 0.8° and Ring 3: C8/C11/C12a/C10a/C9a/C8a & 0.8°. The molecular structure is stabilized by intramolecular O1—H1···N1 interactions. An intramolecular O1—H1···N1 hydrogen bond generates a six-membered ring, producing an S(6) ring motif [Fig. 2] [O1—H1 distance: 0.82 Å, H1—N1 distance: 1.90 Å, O1—N1 distance: 2.634 (3) Å and O1—H1···N1 angle 148 °]. (Bernstein et al., 1995). The crystal packing exhibits intermolecular π—π stacking interactions (Fig. 3) between the aromatic rings with the centroid-to-centroid distance of 3.851 (2) Å.

Related literature top

For hydrogen-bond motifs, see: Bernstein et al. (1995). For applications of Schiff base ligands, see: Pandeya et al. (1999, 2000); Singh & Dash (1988); Kelley et al. (1995); Turan-Zitouni et al. (2007); Tarafder et al. (2002); Sakyan et al. (2004); Gianneshi et al. (2005); Morris et al. (2001); Lu et al. (2007); Lau et al. (1999). For a related structure, see: Al-Douh et al. (2009).

Experimental top

1,5-naphthalenediamine (158 mg, 1 mmol) was taken in a 100 ml round bottom schlenk flask and the system was evacuated and purged with nitrogen. To this, a freshly distilled ethanol (40 ml), salicylaldehyde (0.2 ml, 2 mmol) and 2 drops of acetic acid were added. The reaction mixture was stirred at 25 °C for 3 h. The solvent was evaporated using vacuum and the yellow color product was purified by recrystallization with dichloromethane (Yield 73%, Melting Point: 220 °C). Single crystals suitable for X-ray diffraction were prepared by slow evaporation of a solution of the title compound in dichloromethane at room temperature. Spectroscopic data of the title compound: IR (KBr): ν 3442 (m), 1615 (s), 1454 (w), 1278 (m), 1143 (m), 744 (s), cm^{-1. 1}H NMR (400 MHz, CDCl₃): δ 13.30 (s, 2H), 8.74 (s, 2H), 8.21 (d, 2H), 7.57 (t, 2H), 7.49–7.72 (m, 4H), 7.25 (d, 2H), 7.12 (d, 2H), 7.0 (t, 2H). ¹³C NMR (100 MHz, CDCl₃): δ 164.0, 161.4, 146.4, 133.7, 132.6, 129.0, 126.7, 122.4, 119.6, 119.4, 117.5, 115.0.

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2009); cell refinement: CrysAlis PRO (Oxford Diffraction, 2009); data reduction: CrysAlis PRO (Oxford Diffraction, 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); software used to prepare material for publication: PLATON (Spek, 2009).

Figures top

	Fig. 1. The molecular structure of title compound, showing displacement ellipsoids drawn at the 50% probability level.
	Fig. 2. A view of the intramolecular S (6) ring motif formed by an O—H···N interaction in the title compound. The motif forming atoms are shown in a ball and stick representation and the hydrogen bond is shown as a red dashed line.
	Fig. 3. View of the crystal packing showing intermolecular π···π stacking interactions. Cg(1), Cg(2) and Cg(3) are the centroids of the C1/C2/C3/C4/C5/C6, C8/C9/C10/C12/C11a/C8a and C8/C11/C12a/C10a/C9a/C8a rings respectively.

2,2'-[Naphthalene-1,5-diylbis(nitrilomethanylylidene)]diphenol top

Crystal data top

C₂₄H₁₈N₂O₂	F(000) = 384
M_r = 366.40	D_x = 1.388 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 4711 reflections
a = 3.8510 (9) Å	θ = 3.5–25.0°
b = 19.395 (6) Å	µ = 0.09 mm⁻¹
c = 11.796 (2) Å	T = 293 K
β = 95.85 (3)°	Block, yellow
V = 876.4 (4) Å³	0.23 × 0.15 × 0.11 mm
Z = 2

Data collection top

Oxford Diffraction Xcalibur-S diffractometer	1544 independent reflections
Radiation source: fine-focus sealed tube	1004 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.099
Detector resolution: 15.9948 pixels mm^-1	θ_max = 25.0°, θ_min = 3.5°
ω scans	h = −4→3
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009)	k = −22→23
T_min = 0.980, T_max = 0.990	l = −13→13
4711 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)] = 0.080	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.206	H-atom parameters constrained
S = 1.18	w = 1/[σ²(F_o²) + (0.1P)²] where P = (F_o² + 2F_c²)/3
1544 reflections	(Δ/σ)_max < 0.001
128 parameters	Δρ_max = 0.35 e Å⁻³
0 restraints	Δρ_min = −0.36 e Å⁻³

Crystal data top

C₂₄H₁₈N₂O₂	V = 876.4 (4) Å³
M_r = 366.40	Z = 2
Monoclinic, P2₁/c	Mo Kα radiation
a = 3.8510 (9) Å	µ = 0.09 mm⁻¹
b = 19.395 (6) Å	T = 293 K
c = 11.796 (2) Å	0.23 × 0.15 × 0.11 mm
β = 95.85 (3)°

Data collection top

Oxford Diffraction Xcalibur-S diffractometer	1544 independent reflections
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009)	1004 reflections with I > 2σ(I)
T_min = 0.980, T_max = 0.990	R_int = 0.099
4711 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.080	0 restraints
wR(F²) = 0.206	H-atom parameters constrained
S = 1.18	Δρ_max = 0.35 e Å⁻³
1544 reflections	Δρ_min = −0.36 e Å⁻³
128 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
N1	0.3017 (6)	0.64602 (13)	−0.0063 (2)	0.0372 (7)
C1	0.5621 (8)	0.77817 (16)	0.0770 (3)	0.0380 (8)
C6	0.3700 (7)	0.76789 (15)	−0.0294 (3)	0.0355 (8)
C8	0.0499 (7)	0.53316 (14)	0.0215 (3)	0.0331 (8)
C7	0.2450 (8)	0.70066 (16)	−0.0666 (3)	0.0390 (8)
H7	0.1174	0.6968	−0.1376	0.047*
C9	0.1929 (7)	0.58080 (15)	−0.0513 (3)	0.0361 (8)
O1	0.6420 (7)	0.72510 (12)	0.1490 (2)	0.0531 (8)
H1	0.5617	0.6893	0.1202	0.080*
C11	−0.0030 (8)	0.54993 (16)	0.1351 (3)	0.0381 (8)
H11	0.0586	0.5934	0.1638	0.046*
C5	0.2987 (9)	0.82501 (16)	−0.1005 (3)	0.0428 (9)
H5	0.1709	0.8190	−0.1711	0.051*
C10	0.2399 (8)	0.56269 (17)	−0.1607 (3)	0.0384 (8)
H10	0.3368	0.5942	−0.2078	0.046*
C2	0.6767 (8)	0.84352 (17)	0.1085 (3)	0.0442 (9)
H2	0.8043	0.8504	0.1788	0.053*
C12	−0.1435 (8)	0.50288 (16)	0.2025 (3)	0.0398 (8)
H12	−0.1760	0.5143	0.2773	0.048*
C3	0.6030 (9)	0.89849 (18)	0.0363 (3)	0.0484 (10)
H3	0.6824	0.9422	0.0585	0.058*
C4	0.4136 (9)	0.88975 (18)	−0.0682 (3)	0.0471 (9)
H4	0.3641	0.9273	−0.1163	0.057*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0418 (13)	0.0354 (15)	0.0331 (17)	−0.0021 (11)	−0.0027 (12)	0.0029 (12)
C1	0.0390 (15)	0.0432 (19)	0.031 (2)	0.0014 (13)	0.0018 (15)	0.0017 (15)
C6	0.0381 (15)	0.0395 (18)	0.028 (2)	−0.0038 (13)	−0.0007 (14)	0.0010 (15)
C8	0.0324 (13)	0.0363 (16)	0.0288 (19)	0.0033 (12)	−0.0058 (13)	0.0026 (14)
C7	0.0399 (16)	0.0445 (19)	0.031 (2)	−0.0027 (13)	−0.0045 (14)	−0.0004 (15)
C9	0.0338 (14)	0.0405 (18)	0.032 (2)	−0.0013 (13)	−0.0065 (14)	−0.0012 (15)
O1	0.0687 (16)	0.0534 (15)	0.0332 (16)	−0.0045 (12)	−0.0141 (12)	0.0057 (12)
C11	0.0404 (16)	0.0384 (17)	0.034 (2)	0.0013 (13)	−0.0035 (14)	−0.0021 (16)
C5	0.0516 (18)	0.0440 (19)	0.031 (2)	−0.0015 (15)	−0.0023 (16)	0.0016 (16)
C10	0.0400 (16)	0.0456 (19)	0.029 (2)	−0.0017 (13)	0.0012 (14)	0.0067 (15)
C2	0.0442 (17)	0.052 (2)	0.034 (2)	−0.0037 (15)	−0.0051 (15)	−0.0082 (16)
C12	0.0443 (16)	0.051 (2)	0.0241 (19)	0.0029 (14)	0.0012 (15)	−0.0032 (15)
C3	0.0515 (19)	0.0410 (19)	0.052 (3)	−0.0047 (15)	0.0024 (18)	−0.0059 (18)
C4	0.056 (2)	0.043 (2)	0.042 (2)	0.0001 (15)	0.0030 (18)	0.0070 (17)

Geometric parameters (Å, º) top

N1—C7	1.283 (4)	C11—C12	1.358 (5)
N1—C9	1.418 (4)	C11—H11	0.9300
C1—O1	1.350 (4)	C5—C4	1.372 (5)
C1—C2	1.381 (4)	C5—H5	0.9300
C1—C6	1.404 (4)	C10—C12ⁱ	1.400 (4)
C6—C5	1.400 (4)	C10—H10	0.9300
C6—C7	1.443 (4)	C2—C3	1.376 (5)
C8—C9	1.411 (5)	C2—H2	0.9300
C8—C11	1.414 (4)	C12—C10ⁱ	1.400 (4)
C8—C8ⁱ	1.421 (6)	C12—H12	0.9300
C7—H7	0.9300	C3—C4	1.378 (5)
C9—C10	1.367 (5)	C3—H3	0.9300
O1—H1	0.8200	C4—H4	0.9300

C7—N1—C9	120.2 (3)	C8—C11—H11	119.8
O1—C1—C2	119.0 (3)	C4—C5—C6	121.3 (3)
O1—C1—C6	121.3 (3)	C4—C5—H5	119.3
C2—C1—C6	119.7 (3)	C6—C5—H5	119.3
C1—C6—C5	118.4 (3)	C9—C10—C12ⁱ	120.7 (3)
C1—C6—C7	122.0 (3)	C9—C10—H10	119.7
C5—C6—C7	119.6 (3)	C12ⁱ—C10—H10	119.7
C9—C8—C11	121.9 (3)	C3—C2—C1	120.3 (3)
C9—C8—C8ⁱ	119.0 (4)	C3—C2—H2	119.8
C11—C8—C8ⁱ	119.1 (4)	C1—C2—H2	119.8
N1—C7—C6	123.0 (3)	C11—C12—C10ⁱ	120.7 (3)
N1—C7—H7	118.5	C11—C12—H12	119.6
C6—C7—H7	118.5	C10ⁱ—C12—H12	119.6
C10—C9—C8	120.2 (3)	C2—C3—C4	121.0 (3)
C10—C9—N1	121.3 (3)	C2—C3—H3	119.5
C8—C9—N1	118.4 (3)	C4—C3—H3	119.5
C1—O1—H1	109.5	C5—C4—C3	119.2 (3)
C12—C11—C8	120.3 (3)	C5—C4—H4	120.4
C12—C11—H11	119.8	C3—C4—H4	120.4

O1—C1—C6—C5	−179.4 (3)	C9—C8—C11—C12	179.6 (3)
C2—C1—C6—C5	−0.3 (5)	C8ⁱ—C8—C11—C12	0.8 (5)
O1—C1—C6—C7	0.7 (5)	C1—C6—C5—C4	0.3 (5)
C2—C1—C6—C7	179.8 (3)	C7—C6—C5—C4	−179.9 (3)
C9—N1—C7—C6	−175.5 (3)	C8—C9—C10—C12ⁱ	0.7 (4)
C1—C6—C7—N1	−0.5 (5)	N1—C9—C10—C12ⁱ	177.5 (3)
C5—C6—C7—N1	179.7 (3)	O1—C1—C2—C3	179.2 (3)
C11—C8—C9—C10	−180.0 (3)	C6—C1—C2—C3	0.1 (5)
C8ⁱ—C8—C9—C10	−1.2 (5)	C8—C11—C12—C10ⁱ	−0.4 (4)
C11—C8—C9—N1	3.2 (4)	C1—C2—C3—C4	0.2 (5)
C8ⁱ—C8—C9—N1	−178.0 (3)	C6—C5—C4—C3	0.1 (5)
C7—N1—C9—C10	43.0 (4)	C2—C3—C4—C5	−0.3 (5)
C7—N1—C9—C8	−140.2 (3)

Symmetry code: (i) −x, −y+1, −z.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1	0.82	1.90	2.634 (3)	148

Experimental details

Crystal data
Chemical formula	C₂₄H₁₈N₂O₂
M_r	366.40
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	3.8510 (9), 19.395 (6), 11.796 (2)
β (°)	95.85 (3)
V (Å³)	876.4 (4)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.23 × 0.15 × 0.11

Data collection
Diffractometer	Oxford Diffraction Xcalibur-S diffractometer
Absorption correction	Multi-scan (CrysAlis PRO; Oxford Diffraction, 2009)
T_min, T_max	0.980, 0.990
No. of measured, independent and observed [I > 2σ(I)] reflections	4711, 1544, 1004
R_int	0.099
(sin θ/λ)_max (Å⁻¹)	0.594

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.080, 0.206, 1.18
No. of reflections	1544
No. of parameters	128
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.35, −0.36

Computer programs: CrysAlis PRO (Oxford Diffraction, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1	0.82	1.90	2.634 (3)	148

Footnotes

‡Additional correspondence author, e-mail: krishstrucbio@gmail.com.

Acknowledgements

BM thanks the Department of Science and Technology (DST), Government of India, New Delhi, for financial support. RK thanks the Centre for Bioinformatics [Funded by the Department of Biotechnology (DBT) and the Department of Information Technology (DIT)], Pondicherry University, for providing computational facilities to carry out this research work. JM thanks the Council for Scientific and Industrial Research (CSIR) for a Senior Research Fellowship (SRF).

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