4-Fluoro-N-(4-hy­droxy­benzyl­idene)aniline

L Jothi; G Anuradha; G Vasuki; R Ramesh Babu; K Ramamurthi

doi:10.1107/S1600536814015153

. 2014 Jul 11;70(Pt 8):o860. doi: 10.1107/S1600536814015153

4-Fluoro-N-(4-hydroxybenzylidene)aniline

L Jothi ^a, G Anuradha ^b,^*, G Vasuki ^b,^*, R Ramesh Babu ^c, K Ramamurthi ^d

PMCID: PMC4158537 PMID: 25249910

Abstract

In the title compound, C₁₃H₁₀FNO, the benzene ring planes are inclined at an angle of 50.52 (8)°. A characteristic of aromatic Schiff bases with N-aryl substituents is that the terminal phenyl rings are twisted relative to the plane of the HC=N link between them. In this case, the HC=N unit makes dihedral angles of 10.6 (2) and 40.5 (2)° with the hydroxybenzene and flurobenzene rings, respectively. In the crystal, O—H⋯N and C—H⋯F hydrogen bonds lead to the formation of chains along the c- and b-axis directions, respectively. C—H⋯π contacts link molecules along a and these contacts combine to generate a three-dimensional network with molecules stacked along the b-axis direction.

Keywords: crystal structure

Related literature

For manufacturing and pharmaceutical applications of Schiff base compounds, see: Akkurt et al. (2013 ▶). For related structures, see: Li et al. (2008 ▶); Zhang (2010 ▶); Jothi et al., (2012a ▶,b ▶). For standard bond lengths, see: Allen et al. (1987 ▶) and for hydrogen-bond motifs, see: Bernstein et al. (1995 ▶). graphic file with name e-70-0o860-scheme1.jpg

Experimental

Crystal data

C₁₃H₁₀FNO
M _r = 215.22
Orthorhombic,
a = 11.0153 (8) Å
b = 9.8596 (7) Å
c = 9.5476 (6) Å
V = 1036.93 (12) Å³
Z = 4
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 296 K
0.30 × 0.20 × 0.20 mm

Data collection

Bruker KappaCCD APEXII diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2004 ▶) T _min = 0.971, T _max = 0.980
6612 measured reflections
1430 independent reflections
1282 reflections with I > 2σ(I)
R _int = 0.033
θ_max = 23.4°

Refinement

R[F ² > 2σ(F ²)] = 0.029
wR(F ²) = 0.078
S = 1.11
1430 reflections
146 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 0.13 e Å⁻³
Δρ_min = −0.12 e Å⁻³

Data collection: APEX2 (Bruker, 2004 ▶); cell refinement: APEX2 and SAINT-Plus (Bruker, 2004 ▶); data reduction: SAINT-Plus and XPREP (Bruker, 2004 ▶); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: Mercury (Macrae et al., 2008 ▶); software used to prepare material for publication: WinGX (Farrugia, 2012 ▶) and PLATON (Spek, 2009 ▶).

Supplementary Material

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536814015153/sj5413sup1.cif

e-70-0o860-sup1.cif^{(21.4KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536814015153/sj5413Isup2.hkl

e-70-0o860-Isup2.hkl^{(78.9KB, hkl)}

Click here for additional data file.^{(4.1KB, cml)}

Supporting information file. DOI: 10.1107/S1600536814015153/sj5413Isup3.cml

CCDC reference: 924015

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

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

Cg is the centroid of the C1–C6 benzene ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯N1ⁱ	0.82	1.94	2.756 (2)	176
C9—H9⋯F1ⁱⁱ	0.93	2.61	3.263 (3)	127
C13—H13⋯Cg ⁱⁱⁱ	0.93	2.83	3.710 (3)	157

Open in a new tab

Symmetry codes: (i) Inline graphic ; (ii) ; (iii) .

Acknowledgments

The authors thank the Sophisticated Analytical Instrument Facility, IIT-Madras, Chennai-36, for the data collection.

supplementary crystallographic information

S1. Comment

Schiff base compounds have been used as fine chemicals and pharmaceutical substrates (Akkurt et al., 2013). They are important ligands in coordination chemistry due to their ease of preparation and ability to be modified both electronically and sterically (Li et al., 2008 and Zhang, 2010). As a part of our study into the co-ordination behaviour of ligands having a 4-hydroxy substituent on the benzylidene fragment, X-ray structural analysis of the title compound was carried out, and the results are reported herein.

The title compound, (I), contains two benzene rings bridged by an HC ═N imine unit, with the planes of the rings inclined at an angle of 50.52 (8)°, showing significant deviation of the molecule from planarity as observed in the related structures 4-bromo-N-(4-hydroxybenzylidene)aniline and 4-[(E)-(4-methylphenyl)iminomethyl]phenol (Jothi et al., 2012a,b). The molecule exists in the solid state in an E-configuration with respect to the C7 ═N1 double bond as indicated by the torsion angle C4–C7–N1–C8= -171.2 (2)°. The C4–C7 [1.456 (3) Å] and N1–C8 [1.430 (3) Å] distances confirm a degree of electron delocalization between the benzene rings, and the molecule can be regarded as a partially delocalized π-electron system. All other bond lengths are within the expected ranges (Allen et al., 1987).

In the crystal, the molecules are linked by O1—H1···N1 hydrogen bonds to form infinite one-dimensional zigzag chains with graph set notation C(8) (Bernstein et al.,, 1995) along the c axis, Fig 2. Weaker C9—H9···F1 contacts also propagate C(5) zigzag chains along b, Fig 3, with molecules in this chain forming a V-shaped stacking motif when viewed along a, Fig 4. Finally C13—H13···π contacts also form chains along a, Fig 5. These contacts combine to stack the molecules in a head to tail zigzag fashion along the b axis direction, Fig 6.

S2. Experimental

4-Fluoro-4-hydroxybenzylideneaniline was prepared by mixing equimolar amounts of 4-hydroxy benzaldehyde and 4-fluoro aniline in ethanol (40 ml). The reaction mixture was refluxed for about 6 h and the resulting solution was slowly evaporated at room temperature. After three days single crystals of the title compound, suitable for X-ray structure analysis were obtained.