4-Meth­oxy-2-[(E)-(phenyl­imino)meth­yl]phenol

Selma Uçan; Aslı Öztürk; Nursabah Sarıkavaklı; Tuncer Hökelek

doi:10.1107/S1600536808026883

. 2008 Aug 23;64(Pt 9):o1818–o1819. doi: 10.1107/S1600536808026883

4-Methoxy-2-[(E)-(phenylimino)methyl]phenol

Selma Uçan ^a, Aslı Öztürk ^b, Nursabah Sarıkavaklı ^c, Tuncer Hökelek ^b,^*

PMCID: PMC2960573 PMID: 21201794

Abstract

In the molecule of the title compound, C₁₄H₁₃NO₂, the two aromatic rings are oriented at a dihedral angle of 0.78 (20)°; with the exception of two methyl H atoms the molecule is essentially planar. The intramolecular O—H⋯N hydrogen bond results in the formation of a non-planar, six-membered ring, which adopts a flattened-boat conformation. In the crystal structure, intermolecular C—H⋯O hydrogen bonds link the molecules to form parallel networks. There is a C—H⋯π contact between the methyl group and the benzene ring. A π–π contact between the benzene and phenyl rings [centroid–centroid distance = 4.681 (5) Å] is also observed.

Related literature

For general background, see: Hökelek et al. (2004 ▶); Uçan & Mercimek (2005 ▶); Uçan et al. (2005 ▶); Garg & Kumar (2003 ▶); Mokles & Elzaher (2001 ▶); Amirnasr et al. (2002 ▶); Bella et al. (2004 ▶); Chandra & Kumar (2005 ▶); Ray et al. (2003 ▶); Yang et al. (2000 ▶). For bond-length data, see: Allen et al. (1987 ▶). For ring conformation puckering parameters, see: Cremer & Pople (1975 ▶).

Experimental

Crystal data

C₁₄H₁₃NO₂
M _r = 227.26
Monoclinic,
a = 20.935 (2) Å
b = 4.7151 (10) Å
c = 12.275 (3) Å
β = 106.623 (14)°
V = 1161.1 (4) Å³
Z = 4
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 294 (2) K
0.40 × 0.20 × 0.10 mm

Data collection

Enraf–Nonius TurboCAD-4 diffractometer
Absorption correction: ψ scan (North et al., 1968 ▶) T _min = 0.971, T _max = 0.990
1653 measured reflections
1560 independent reflections
521 reflections with I > 2σ(I)
R _int = 0.048
θ_max = 23.1°
3 standard reflections frequency: 120 min intensity decay: 1%

Refinement

R[F ² > 2σ(F ²)] = 0.064
wR(F ²) = 0.207
S = 0.92
1560 reflections
163 parameters
1 restraint
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.20 e Å⁻³
Δρ_min = −0.20 e Å⁻³

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994 ▶); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995 ▶); 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, 2003 ▶); software used to prepare material for publication: WinGX publication routines (Farrugia, 1999 ▶) and PLATON.

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808026883/wn2275sup1.cif

e-64-o1818-sup1.cif^{(16.4KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808026883/wn2275Isup2.hkl

e-64-o1818-Isup2.hkl^{(45.1KB, hkl)}

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

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯N1	0.86 (5)	1.82 (5)	2.604 (7)	152 (5)
C7—H7⋯O1ⁱ	1.03 (5)	2.55 (6)	3.493 (10)	151 (4)
C14—H14A⋯O2ⁱⁱ	0.96	2.57	3.500 (6)	164
C14—H14B⋯Cg2ⁱⁱⁱ	0.96	3.27	4.142 (8)	152

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Symmetry codes: (i) Inline graphic ; (ii) ; (iii) . Cg2 is the centroid of ring C8–C13.

Acknowledgments

The authors acknowledge the purchase of the CAD-4 diffractometer under grant DPT/TBAG1 of the Scientific and Technical Research Council of Turkey.

supplementary crystallographic information

Comment

Few classes of coordination compounds have been the subject of as much attention as Schiff base complexes formed by the condensation of amines with carbonyl derivatives (Hökelek et al., 2004; Uçan & Mercimek, 2005; Uçan et al., 2005). Schiff bases of diamines and their complexes have a variety of applications including biological, clinical and analytical (Garg & Kumar, 2003; Mokles & Elzaher, 2001; Amirnasr et al., 2002). A great number of Schiff base complexes with metals have provoked wide interest because they possess a diverse spectrum of biological and pharmaceutical activities, such as antitumor and antioxidative activities, as well as the inhibition of lipid peroxidation (Bella et al., 2004; Chandra & Kumar, 2005; Ray et al., 2003; Yang et al., 2000). We report here the crystal structure of the title compound.

In the molecule of the title compound, (Fig. 1) the bond lengths (Allen et al., 1987) and angles are generally within normal ranges. Rings A (C1—C6) and B (C8—C13) are, of course, planar, and they are oriented at a dihedral angle of 0.78 (20)°; with the exception of two methyl H atoms the molecule is essentially planar. It is known that Schiff bases may exhibit thermochromism or photochromism, depending on the planarity or non-planarity of the molecule, respectively. Therefore, one can expect thermochromic properties in the title compound as a result of the planarity of the molecule. The intramolecular O—H···N hydrogen bond (Table 1) results in the formation of a non-planar, six-membered ring C (N1/O1/C7/C8/C13/H1); this adopts a flattened-boat conformation having a total puckering amplitude, Q_T, of 0.381 (3) Å (Cremer & Pople, 1975).

In the crystal structure, intermolecular C—H···O hydrogen bonds (Table 1) link the molecules to form a network structure (Fig. 2), in which they are arranged parallel to each other (Fig. 3). A C—H···π contact (Table 1) between the methyl group and B ring is observed. A π—π contact between the A and B rings Cg1···Cg2ⁱ [symmetry code: (i) x, y - 1, z, where Cg1 and Cg2 are the centroids of the rings A and B, respectively, further stabilizes the structure, with a centroid-centroid distance of 4.681 (5) Å.

Experimental

The title compound was prepared by the usual condensation method. Aniline (0.931 g, 10 mmol) was dissolved in methanol (10 ml) and added to a solution of 4-methoxysalicylaldehyde (3.042 g, 20 mmol) in methanol (10 ml). The reaction mixture was stirred for 3 h and left overnight at 298 K. The resulting precipitate was filtered and washed with cold ethanol. It was recrystalized from dichloromethane, dried in a vacuum desiccator and the purity was checked by TLC (yield; 3.854 g, 84%, m.p. 341 K).