4-[(E)-(4-Fluoro­benzyl­idene)amino]-3-methyl-1H-1,2,4-triazole-5(4H)-thione

H C Devarajegowda; S Jeyaseelan; R Sathishkumar; Agnes Sylvia D’souza; Alphonsus D’souza

doi:10.1107/S1600536812019174

. 2012 May 5;68(Pt 6):o1607. doi: 10.1107/S1600536812019174

4-[(E)-(4-Fluorobenzylidene)amino]-3-methyl-1H-1,2,4-triazole-5(4H)-thione

H C Devarajegowda ^a,^*, S Jeyaseelan ^a, R Sathishkumar ^b, Agnes Sylvia D’souza ^c, Alphonsus D’souza ^c

PMCID: PMC3379215 PMID: 22719413

Abstract

In the asymmetric unit of the title compound, C₁₀H₉FN₄S, there are two independent molecules in which the dihedral angles between the 1,2,4-triazole and benzene rings are 36.85 (10) and 7.81 (10)°. In the crystal, N—H⋯S interactions link pairs of independent molecules into dimers. There are also π–π interactions between the triazole and benzene rings of inversion-related pairs of the more planar molecule [centroid–centroid distance = 3.6430 (13) Å].

Related literature

For background information on the properties and uses of chalcone derivatives, see: Temple (1981 ▶); Holla et al. (1998 ▶); Heidelberger et al. (1957 ▶); Andersson & MacGowan (2003 ▶). For a related structure, see: Devarajegowda et al. (2010 ▶).

Experimental

Crystal data

C₁₀H₉FN₄S
M _r = 236.27
Triclinic,
a = 9.0048 (19) Å
b = 10.811 (2) Å
c = 12.729 (3) Å
α = 101.205 (3)°
β = 103.899 (3)°
γ = 112.376 (3)°
V = 1054.4 (4) Å³
Z = 4
Mo Kα radiation
μ = 0.30 mm⁻¹
T = 293 K
0.52 × 0.24 × 0.13 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2007 ▶) T _min = 0.77, T _max = 1.00
9923 measured reflections
3698 independent reflections
3383 reflections with I > 2σ(I)
R _int = 0.017

Refinement

R[F ² > 2σ(F ²)] = 0.033
wR(F ²) = 0.085
S = 1.05
3698 reflections
291 parameters
H-atom parameters constrained
Δρ_max = 0.30 e Å⁻³
Δρ_min = −0.28 e Å⁻³

Data collection: SMART (Bruker, 2001 ▶); cell refinement: SAINT (Bruker, 2001 ▶); 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 (Farrugia, 1997 ▶); software used to prepare material for publication: SHELXL97.

Supplementary Material

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536812019174/pk2403sup1.cif

e-68-o1607-sup1.cif^{(22.3KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812019174/pk2403Isup2.hkl

e-68-o1607-Isup2.hkl^{(177.6KB, hkl)}

Supplementary material file. DOI: 10.1107/S1600536812019174/pk2403Isup3.cml

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
N3A—H3A⋯S1B	0.86	2.45	3.2840 (18)	164
N3B—H3B⋯S1A	0.86	2.51	3.3691 (18)	172

Open in a new tab

Acknowledgments

The authors thank Professor T. N. Guru Row, Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore, for the data collection.

supplementary crystallographic information

Comment

4-Amino-5-mercapto-1,2,4-triazoles are the starting materials for the synthesis of a wide variety of heterocyclic derivatives which are of great importance in medicinal chemistry (Temple, 1981). Many Schiff & Mannich bases derived from 1,2,4-triazoles possess protozoacidal and bactericidal activities (Holla et al., 1998). Furthermore, fluorinated heterocycles have been shown to exhibit a wide variety of biocidal activities. Compounds such as fluorouracil and fluoroquinolone etc. have been used as anticancer agents and antibiotics respectively (Heidelberger et al., 1957; Andersson & MacGowan, 2003).

The asymmetric unit of crystals of 4-{[(1E)-(4-fluorophenyl)methylene] amino}-5-methyl-2,4-dihydro-3H-1,2,4-triazole-3-thione, C₁₀H₉F N₄S, contain two crystallographically independent molecules (Fig. 1). The 1,2,4 triazole rings (N3A,N4A,N5A,C8A,C9A and (N3B,N4B,N5B,C8B,C9B) are not coplanar with their respective benzene ring (C11A—C16A) and (C11B—C16B) systems; the dihedral angle between the two planes being 36.85 (10)° and 7.81 (10)° in the two molecules. In the crystal, N3A—H3A···S1B and N3B—H3B···S1A interactions link pairs of inequivalent molecules into dimers (Table 1.). Finally, π-π interactions between inversion-related pairs of the more planar molecule occur between the triazole (N3B,N4B,N5B,C8B,C9B) and benzene (C11B—C16B) rings [centroid-centroid distance = 3.6430 (13) Å], which stabilize the crystal packing (Fig. 2).

Experimental

An equimolar mixture of the triazole (1; 0.02 mol) and 4-fluorobenzaldehyde (0.02 mol) in absolute ethanol (30 ml) was refluxed with concentrated H₂SO₄ (0.5 ml) for 1–2 hrs. On cooling the reaction mixture, the solid product was separated and re-crystallized using ethanol as solvent.