N′-[(1E)-(4-Fluoro­phen­yl)methyl­idene]thio­phene-2-carbohydrazide

Amer M Alanazi; Siham Lahsasni; Ali A El-Emam; Seik Weng Ng

doi:10.1107/S1600536811056121

. 2012 Jan 11;68(Pt 2):o314. doi: 10.1107/S1600536811056121

N′-[(1E)-(4-Fluorophenyl)methylidene]thiophene-2-carbohydrazide

Amer M Alanazi ^a, Siham Lahsasni ^a, Ali A El-Emam ^a, Seik Weng Ng ^b,^c,^*

PMCID: PMC3275004 PMID: 22346949

Abstract

In the title compound, C₁₂H₉FN₂OS, the thienyl ring is disordered over two positions, with the S atom of the major component [occupancy = 87.08 (16)°] oriented towards the ortho-H atom of the benzene ring. The molecule is nearly planar, the dihedral angle between the thiophene and benzene rings being 13.0 (2)° in the major component. The azomethine C=N double bond in the molecule is of an E configuration. In the crystal, molecules are linked by pairs of N—H⋯O hydrogen bonds, forming inversion dimers.

Related literature

For the 4-chloro and 4-bromo derivatives, see: Jiang (2010a ▶,b ▶).

Experimental

Crystal data

C₁₂H₉FN₂OS
M _r = 248.27
Monoclinic,
a = 13.3076 (11) Å
b = 5.6015 (4) Å
c = 15.3062 (12) Å
β = 104.166 (9)°
V = 1106.27 (15) Å³
Z = 4
Mo Kα radiation
μ = 0.29 mm⁻¹
T = 100 K
0.35 × 0.15 × 0.05 mm

Data collection

Agilent SuperNova Dual diffractometer with an Atlas detector
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2010 ▶) T _min = 0.906, T _max = 0.986
4609 measured reflections
2532 independent reflections
1917 reflections with I > 2σ(I)
R _int = 0.037

Refinement

R[F ² > 2σ(F ²)] = 0.043
wR(F ²) = 0.108
S = 1.06
2532 reflections
171 parameters
5 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.30 e Å⁻³
Δρ_min = −0.28 e Å⁻³

Data collection: CrysAlis PRO (Agilent, 2010 ▶); 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: X-SEED (Barbour, 2001 ▶); software used to prepare material for publication: publCIF (Westrip, 2010 ▶).

Supplementary Material

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S1600536811056121/xu5417sup1.cif

e-68-0o314-sup1.cif^{(17.3KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536811056121/xu5417Isup2.hkl

e-68-0o314-Isup2.hkl^{(124.4KB, 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
N1—H1⋯O1ⁱ	0.90 (2)	1.99 (3)	2.893 (2)	176 (2)

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Symmetry code: (i) Inline graphic .

Acknowledgments

We thank the Deanship of Scientific Research and the Research Center of the College of Pharmacy, King Saud University, and the University of Malaya for supporting this study.

supplementary crystallographic information

Comment

2-Thienoylhydrazide forms a large number of Schiff base derivatives with substituted benzaldehydes; among those whose crystal structures have been reported are the 4-chloro and 4-bromo derivatives (Jiang, 2010a, 2010b). However, the 4-fluoro analog (Scheme I) is disordered in respect of the thienyl ring (Fig. 1). The azomethine double-bond in the approximately planar C₁₂H₉FN₂OS molecule is of an E configuration. The thienyl ring is disordered over two positions, with the S atom of the major component (87.1 (2) %) oriented towards the ortho-H atom of the benzene ring. Two molecules are linked across a center-of-inversion by an N–H···O hydrogen bond to generate a dimer (Table 1).

Experimental

2-Thienoylhydrazide (1.42 g, 0.01 mol) and 4-fluorobenzaldehyde (1.24 g, 0.01 mol) dissolved in ethanol (8 ml) was heated for 1 h. The product was collected and recystallized from ethanol to yield the Schiff base in 90% yield, m.p. 447–448 K.