Crystal structure of (Z)-3-benz­yloxy-6-[(2-hy­droxy-5-methyl­anilino)methyl­idene]cyclo­hexa-2,4-dien-1-one

Nadir Ghichi; Ali Benosmane; Ali Benboudiaf; Hocine Merazig

doi:10.1107/S1600536814016936

. 2014 Aug 1;70(Pt 9):o957–o958. doi: 10.1107/S1600536814016936

Crystal structure of (Z)-3-benzyloxy-6-[(2-hydroxy-5-methylanilino)methylidene]cyclohexa-2,4-dien-1-one

Nadir Ghichi ^a, Ali Benosmane ^a,^*, Ali Benboudiaf ^a, Hocine Merazig ^a

PMCID: PMC4186113 PMID: 25309278

Abstract

In the title Schiff base compound, C₂₁H₁₉NO₃, the conformation about the C=C bond is Z. The N—H group and carbonyl O atom form an intramolecular N—H⋯O hydrogen bond with an S(6) ring motif. The benzyloxy ring and the 2-hydroxy-5-methylphenyl ring are inclined to the central six-membered ring by 13.68 (9) and 9.13 (8)°, respectively, and to one another by 21.95 (9)°. In the crystal, molecules are linked by O—H⋯O hydrogen bonds, forming helical chains along [010].

Keywords: crystal structure, Schiff base, azomethines

Related literature

For some general background on Schiff bases and their various biological activities, see: Arora et al. (2002 ▶); El-Masry et al. (2000 ▶); Jarrahpour & Khalili (2006 ▶); More et al. (2001 ▶); Phatak et al. (2000 ▶). For related structures, see: Akkurt et al. (2005 ▶, 2008 ▶). For pharmaceutical and industrial applications of azomethines, see: Prakash & Adhikari (2011 ▶). For the effect of hydrophilicity on drug properties, see: Lin & Lu (1997 ▶). graphic file with name e-70-0o957-scheme1.jpg

Experimental

Crystal data

C₂₁H₁₉NO₃
M _r = 333.37
Monoclinic,
a = 12.594 (5) Å
b = 9.303 (5) Å
c = 14.997 (5) Å
β = 96.402 (5)°
V = 1746.1 (13) Å³
Z = 4
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 293 K
0.03 × 0.02 × 0.01 mm

Data collection

Bruker APEXII CCD diffractometer
19603 measured reflections
5148 independent reflections
2672 reflections with I > 2σ(I)
R _int = 0.037

Refinement

R[F ² > 2σ(F ²)] = 0.050
wR(F ²) = 0.158
S = 1.01
5148 reflections
238 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.22 e Å⁻³
Δρ_min = −0.16 e Å⁻³

Data collection: APEX2 (Bruker, 2006 ▶); cell refinement: SAINT (Bruker, 2006 ▶); data reduction: SAINT; 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, 2012 ▶) and Mercury (Macrae et al., 2008 ▶); software used to prepare material for publication: WinGX (Farrugia, 2012 ▶).

Supplementary Material

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S1600536814016936/su2761sup1.cif

e-70-0o957-sup1.cif^{(20.2KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536814016936/su2761Isup2.hkl

e-70-0o957-Isup2.hkl^{(247KB, hkl)}

Click here for additional data file.^{(6.7KB, cml)}

Supporting information file. DOI: 10.1107/S1600536814016936/su2761Isup3.cml

Click here for additional data file.^{(2MB, tif)}

. DOI: 10.1107/S1600536814016936/su2761fig1.tif

View of the molecular structure of the title molecule, with atom labelling. Displacement ellipsoids are drawn at the 50% probability level.

Click here for additional data file.^{(1.9MB, tif)}

b . DOI: 10.1107/S1600536814016936/su2761fig2.tif

Partial view along the b axis of the crystal packing of the title compound, showing the hydrogen bonds as dashed lines (see Table 1 for details).

CCDC reference: 1015522

Additional supporting information: crystallographic information; 3D view; checkCIF report

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

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1n⋯O2	0.94 (2)	1.83 (2)	2.609 (2)	138.7 (16)
O1—H1o⋯O2ⁱ	0.96 (2)	1.63 (2)	2.590 (2)	176.1 (17)

Open in a new tab

Symmetry code: (i) Inline graphic .

Acknowledgments

The authors thank the MESRS (Algeria) for financial support. We also thank all researchers of the CHEMS Research Unit, University of Constantine 1, Algeria, for their valuable assistance.

supplementary crystallographic information

S1. Experimental

A mixture of 2-amino-4-methylphenol (1 mmol) and 4-(benzyloxy)-2-hydroxybenzaldehyde (1 mmol) was heated to form a clear solution. To this a few drops of conc. HCL was added as a catalyst and the mixture was refluxed for 12 h. After cooling the solution to 80°C it was stirred for 45 min the a precipitate formed. It was filtered off and washed with ice cold ethyl acetate to give the pure title Schiff base compound as an orange solid (yield 35%). This crude product was dissolved in ethyl acetate and two spoons of activated charcoal were added. The mixture was filtered over celiteµ000174 and the product was crystallized from ethyl acetate. The compound was very difficult to crystalize and only after several attempts over a period of four months were crystals suitable for X-ray diffraction analysis finally obtained.