research communications
H-1,2,4-triazole-5(4H)-thione
of 4-amino-3-(thiophen-3-ylmethyl)-1aFaculty of Chemistry, Hanoi National University of Education, 136 Xuan Thuy, Cau Giay, Hanoi, Vietnam, bFaculty of Basic Sciences, University of Mining and Geology, Duc Thang, Bac Tu Liem, Hanoi, Vietnam, cVNU University of Science, Department of Inorganic Chemistry, 19 Le Thanh Tong Street, Hoan Kiem Discrict, Hanoi, Vietnam, and dDepartment of Chemistry, KU Leuven, Biomolecular Architecture, Celestijnenlaan 200F, Leuven (Heverlee), B-3001, Belgium
*Correspondence e-mail: luc.vanmeervelt@kuleuven.be
In the title compound, C7H8N4S2, the thiophene ring shows rotational disorder over two orientations in a 0.6957 (15):0.3043 (15) ratio. The plane of the 1,2,4-triazole ring makes a dihedral angle of 75.02 (17)° with the major-disorder component of the thiophene ring. In the crystal, two types of inversion dimers, described by the graph-set motifs R22(8) and R22(10), are formed by N—H⋯S interactions. Chains of molecules running in the [101] direction are linked by weaker N—H⋯N interactions. The thiophene ring is involved in π–π and C—H⋯π interactions.
Keywords: crystal structure; thiophene; polythiophene; 1,2,4-triazole-3-thione; disorder.
CCDC reference: 1570281
1. Chemical context
Recently, the synthesis, characterization and antifungal activities, together with et al., 2017). Thiophene-containing β-diketonate complexes of copper(II) have been studied and their deposits obtained by electropolymerization have been characterized (Oyarce et al., 2017). Combinations of the thiophene ring with other heterocyclic rings have also been investigated, such as a β-keto–enol group embedded with thiophene and pyridine moieties giving interesting applications in the field of solid-phase extraction (Radi et al., 2016).
determinations, of thiophene-based heterocyclic have been investigated (MingAs part of our ongoing studies of new polythiophenes and their properties (Nguyen et al., 2016; Vu et al., 2016; Vu Quoc et al., 2017), we have synthesized a new thiophene monomer containing an additional 1,2,4-triazole ring. The polymer obtained from 4-amino-3-(thiophen-3-ylmethyl)-1H-1,2,4-triazole-5(4H)-thione using FeCl3 as oxidant was further characterized by IR and NMR spectroscopy, and TGA and is soluble in most common organic solvents, such as DMF and DMSO. We present here the synthesis and of the title compound, 3.
2. Structural commentary
The title compound (Fig. 1) crystallizes in the monoclinic P21/n with one molecule in the The thiophene ring is disordered over two orientations in a rotation of approximately 180° around the C5—C3 bond [occupancy factors = 0.6957 (15) for ring A or S1A/C1A/C2A/C3/C4A and 0.3043 (15) for ring B or S1B/C1B/C2B/C3/C4B]. The 1,2,4-triazole ring is almost planar (r.m.s. deviation = 0.001 Å for ring N2/N3/N4/C6/C7), with the substituents N1, S2 and C5 deviating by −0.034 (1), 0.008 (1) and 0.093 (1) Å, respectively. Due to the sp3 character of the linking atom C5, the planes of the five-membered rings make dihedral angles of 75.02 (17) (ring A) and 76.4 (4)° (ring B), which results in a V-shaped conformation. Atom N1 clearly has an sp3 as shown by the bond angles.
3. Supramolecular features
The crystal packing of the title compound is shown in Fig. 2. The 1H-1,2,4-triazole-5(4H)-thione ring possesses an NH2 group, which, in principle, can act as a donor or acceptor for hydrogen bonding, an NH group, which can act as a donor, and an N atom and C=S group, which can only act as acceptors. Two types of inversion dimers are formed (Fig. 3 and Table 1). The first one, described as graph-set motif R22(8), involves hydrogen bonds between the NH and C=S groups, whereas in the second one, the NH2 group interacts with the C=S grouping, resulting in a ring structure of graph-set R22(10). The second H atom of the NH2 group interacts with the N atom of a neighbouring 1H-1,2,4-triazole-5(4H)-thione ring, resulting in chains of graph-set C(5) in the [101] direction (Fig. 3 and Table 1).
The disordered thiophene ring is only involved in a π–π stacking interaction with the 1,2,4-triazole ring [Cg1⋯Cg3i = 3.415 (2) Å and Cg2⋯Cg3i = 3.440 (5) Å; Cg1, Cg2 and Cg3 are the centroids of ring A, ring B and the 1,2,4-triazole ring, respectively; symmetry code: (i) x + , −y + , z − ; Fig. 4]. The crystal packing shows a weak C—H⋯π interaction (Table 1) and contains no voids.
The packing was further investigated by an analysis of the Hirshfeld surface and two-dimensional fingerprint plots using CrystalExplorer (McKinnon et al., 2007; Spackman & Jayatilaka, 2009). The donors and acceptors corresponding to the N—H⋯S interactions are visible as bright-red spots in Fig. 5(a). The pale-red spots in Fig. 5(b) are the weaker N—H⋯N and C—H⋯N interactions. The relative contributions of the different intermolecular interactions to the Hirshfeld surface area in descending order are: H⋯H (40.4%), S⋯H (26.7%), N⋯H (13.3%), C⋯H (8.2%), C⋯C (4.1%), C⋯N (3.7%), S⋯C (2.3%) and S⋯N (1.2%). This illustrates that the weak N—H⋯N and C—H⋯N interactions contribute significantly to the packing of the title compound.
4. Database survey
A search of the Cambridge Structural Database (CSD, Version 5.38, last update May 2017; Groom et al., 2016) for structures containing an 4-amino-3-methyl-1H-1,2,4-triazole-5(4H)-thione moiety gave 69 hits; in 41 of these structures, the C=S and/or NH2 groups are complexed with a metal ion. The 1,2,4-triazole ring is almost planar, with the largest deviation from the best plane through the ring atoms being 0.034 Å [for the complex mer-trichlorido(dimethyl sulfoxide-κS)(4-amino-3-ethyl-1,2,4-Δ2-triazoline-5-thione-κ2N,S)ruthenium(III) hemihydrate; CSD refcode KESQOO; Cingi et al., 2000].
5. Synthesis and crystallization
The reaction scheme used to synthesize the title compound, 3, is given in Fig. 6. Methyl 2-(thiophen-3-yl)acetate, 1, and 2-(thiophen-3-yl)acetohydrazide, 2, were synthesized as described in a previous study (Vu Quoc et al., 2017).
For the synthesis of 4-amino-3-(thiophen-3-ylmethyl)-1H-1,2,4-triazole-5(4H)-thione, 3, a mixture of hydrazide 2 (5 mmol), KOH (0.01 mol), ethanol (10 ml) and carbon disulfide (10 mmol) was stirred at room temperature until the formation of hydrogen sulfide stopped. An excess of alcohol was removed by distillation and the solid was washed with diethyl ether. A mixture of the resulting solid in water (10 ml) and hydrazine hydrate (15 ml) was then refluxed for 8 h at 353 K. The reaction mixture was cooled and neutralized with dilute hydrochloric acid. The solid which precipitated was filtered off, washed thoroughly with water, dried and recrystallized from an ethanol–water solvent mixture (4:1 v/v) to give 0.63 g (yield 60.0%) of 3 in the form of colourless crystals (m.p. 378 K). IR (Nicolet Impact 410 FT–IR, KBr, cm−1): 3452 (νNH), 3088, 2911 (νCH), 1576 (νC=C thiophene), 1278, 1207 (νC=S). 1H NMR [Bruker XL-500, 500 MHz, d6-DMSO, δ (ppm), J (Hz)]: 7.33 (m, 1H, 4J = 1.0, H2), 7.06 (m, 1H, 2J = 1.0, 5J = 5.0, H4), 7.49 (dd, 1H, 2J = 3.0, 4J = 5.0, H5), 4.04 (s, 2H, H6), 13.54 (s, 1H, H8), 5.58 (s, 2H, H10). 13C NMR [Bruker XL-500, 125 MHz, d6-DMSO, δ (ppm)]: 123.03 (C2), 135.61 (C3), 128.98 (C4), 126.67 (C5), 25.60 (C6), 151.55 (C7), 166.47 (C9). Calculation for C7H8N4S2: M = 212 a.u.
6. Refinement
Crystal data, data collection and structure . Both thiophene rings are disordered over two orientations by a rotation of approximately 180° around the C5—C3 bond. The final occupancy factors are 0.6957 (15) and 0.3043 (15). For the disordered thiophene ring, bond lengths and angles were restrained to the target mean values observed in 3-CH2-thiophene fragments in the CSD (Groom et al., 2016) and the same anisotropic displacement parameters were used for equivalent atoms. The H atoms attached to atoms N1 and N4 were found in a difference density Fourier map and refined freely. The other H atoms were placed at calculated positions and refined in riding mode, with C—H distances of 0.95 (aromatic) and 0.99 Å (CH2), and isotropic displacement parameters equal to 1.2Ueq of the parent atoms. In the final cycles of two reflections showing very poor agreement were omitted as outliers.
details are summarized in Table 2
|
Supporting information
CCDC reference: 1570281
https://doi.org/10.1107/S2056989017012191/zp2023sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989017012191/zp2023Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2056989017012191/zp2023Isup3.cml
Data collection: APEX2 (Bruker, 2014); cell
SAINT (Bruker, 2013); data reduction: SAINT (Bruker, 2013); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).C7H8N4S2 | F(000) = 440 |
Mr = 212.29 | Dx = 1.558 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
a = 7.6904 (4) Å | Cell parameters from 9996 reflections |
b = 13.0429 (7) Å | θ = 3.1–30.7° |
c = 9.0220 (4) Å | µ = 0.54 mm−1 |
β = 90.081 (2)° | T = 100 K |
V = 904.95 (8) Å3 | Block, colorless |
Z = 4 | 0.32 × 0.20 × 0.08 mm |
Bruker APEXII CCD diffractometer | 2536 reflections with I > 2σ(I) |
φ and ω scans | Rint = 0.025 |
Absorption correction: multi-scan (SADABS; Bruker, 2014) | θmax = 30.7°, θmin = 2.8° |
Tmin = 0.710, Tmax = 0.746 | h = −11→11 |
27159 measured reflections | k = −18→18 |
2784 independent reflections | l = −12→12 |
Refinement on F2 | 20 restraints |
Least-squares matrix: full | Hydrogen site location: mixed |
R[F2 > 2σ(F2)] = 0.027 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.071 | w = 1/[σ2(Fo2) + (0.0367P)2 + 0.3687P] where P = (Fo2 + 2Fc2)/3 |
S = 1.05 | (Δ/σ)max = 0.001 |
2784 reflections | Δρmax = 0.43 e Å−3 |
143 parameters | Δρmin = −0.35 e Å−3 |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
S1A | 0.63885 (12) | 0.92996 (9) | −0.14786 (11) | 0.02217 (15) | 0.6957 (15) |
C1A | 0.7802 (4) | 0.9045 (2) | 0.0018 (3) | 0.0237 (6) | 0.6957 (15) |
H1A | 0.894252 | 0.931612 | 0.011838 | 0.028* | 0.6957 (15) |
C2A | 0.7019 (5) | 0.8398 (5) | 0.1017 (6) | 0.0164 (5) | 0.6957 (15) |
H2A | 0.755868 | 0.816279 | 0.190184 | 0.020* | 0.6957 (15) |
S1B | 0.7968 (3) | 0.92242 (15) | −0.0160 (2) | 0.02217 (15) | 0.3043 (15) |
C1B | 0.6169 (13) | 0.9240 (9) | −0.1362 (11) | 0.0237 (6) | 0.3043 (15) |
H1B | 0.606846 | 0.962783 | −0.224912 | 0.028* | 0.3043 (15) |
C2B | 0.4838 (15) | 0.8542 (12) | −0.0748 (15) | 0.0164 (5) | 0.3043 (15) |
H2B | 0.376467 | 0.840204 | −0.122989 | 0.020* | 0.3043 (15) |
C3 | 0.52961 (13) | 0.81192 (7) | 0.05711 (11) | 0.01448 (18) | |
C4A | 0.4817 (8) | 0.8574 (6) | −0.0767 (6) | 0.0211 (5) | 0.6957 (15) |
H4A | 0.371471 | 0.847945 | −0.122328 | 0.025* | 0.6957 (15) |
C4B | 0.6897 (15) | 0.8412 (12) | 0.1007 (13) | 0.0211 (5) | 0.3043 (15) |
H4B | 0.739939 | 0.817943 | 0.190900 | 0.025* | 0.3043 (15) |
C5 | 0.40813 (13) | 0.74501 (8) | 0.14692 (11) | 0.01518 (18) | |
H5A | 0.330663 | 0.706410 | 0.079246 | 0.018* | |
H5B | 0.476853 | 0.694874 | 0.204932 | 0.018* | |
C6 | 0.30116 (12) | 0.80879 (7) | 0.24957 (10) | 0.01347 (17) | |
N3 | 0.14624 (11) | 0.84574 (7) | 0.22259 (9) | 0.01560 (16) | |
N4 | 0.10978 (11) | 0.90487 (7) | 0.34611 (9) | 0.01478 (16) | |
H4 | 0.011 (2) | 0.9399 (12) | 0.3552 (18) | 0.030 (4)* | |
C7 | 0.23720 (12) | 0.90463 (7) | 0.44686 (10) | 0.01315 (17) | |
N2 | 0.36064 (10) | 0.84243 (6) | 0.38483 (9) | 0.01294 (15) | |
S2 | 0.25221 (3) | 0.96465 (2) | 0.61239 (3) | 0.01586 (7) | |
N1 | 0.52086 (11) | 0.81396 (7) | 0.44672 (10) | 0.01611 (17) | |
H1C | 0.5008 (19) | 0.7808 (12) | 0.5337 (17) | 0.023 (4)* | |
H1D | 0.576 (2) | 0.8692 (13) | 0.4631 (17) | 0.028 (4)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
S1A | 0.0285 (3) | 0.0166 (2) | 0.0214 (2) | 0.0005 (2) | 0.0079 (2) | 0.00146 (16) |
C1A | 0.0256 (11) | 0.0213 (13) | 0.0241 (12) | 0.0030 (9) | −0.0027 (9) | 0.0011 (8) |
C2A | 0.0091 (10) | 0.0171 (9) | 0.0229 (9) | −0.0038 (9) | 0.0006 (7) | −0.0041 (7) |
S1B | 0.0285 (3) | 0.0166 (2) | 0.0214 (2) | 0.0005 (2) | 0.0079 (2) | 0.00146 (16) |
C1B | 0.0256 (11) | 0.0213 (13) | 0.0241 (12) | 0.0030 (9) | −0.0027 (9) | 0.0011 (8) |
C2B | 0.0091 (10) | 0.0171 (9) | 0.0229 (9) | −0.0038 (9) | 0.0006 (7) | −0.0041 (7) |
C3 | 0.0150 (4) | 0.0134 (4) | 0.0151 (4) | 0.0023 (3) | 0.0032 (3) | −0.0021 (3) |
C4A | 0.0270 (10) | 0.0233 (12) | 0.0131 (8) | 0.0096 (8) | 0.0020 (7) | 0.0019 (7) |
C4B | 0.0270 (10) | 0.0233 (12) | 0.0131 (8) | 0.0096 (8) | 0.0020 (7) | 0.0019 (7) |
C5 | 0.0145 (4) | 0.0144 (4) | 0.0167 (4) | −0.0002 (3) | 0.0023 (3) | −0.0024 (3) |
C6 | 0.0131 (4) | 0.0131 (4) | 0.0142 (4) | −0.0012 (3) | 0.0011 (3) | 0.0001 (3) |
N3 | 0.0140 (4) | 0.0182 (4) | 0.0146 (4) | 0.0010 (3) | 0.0005 (3) | −0.0022 (3) |
N4 | 0.0124 (4) | 0.0169 (4) | 0.0151 (4) | 0.0027 (3) | 0.0001 (3) | −0.0015 (3) |
C7 | 0.0122 (4) | 0.0127 (4) | 0.0145 (4) | 0.0002 (3) | 0.0019 (3) | 0.0020 (3) |
N2 | 0.0105 (3) | 0.0146 (4) | 0.0138 (3) | 0.0015 (3) | 0.0000 (3) | 0.0007 (3) |
S2 | 0.01442 (12) | 0.01893 (13) | 0.01423 (12) | 0.00179 (8) | −0.00036 (8) | −0.00250 (8) |
N1 | 0.0113 (4) | 0.0190 (4) | 0.0181 (4) | 0.0018 (3) | −0.0029 (3) | 0.0020 (3) |
S1Aa—C1A | 1.763 (4) | C3—C4B | 1.347 (10) |
C1Aa—H1A | 0.9500 | C3—C5 | 1.5143 (14) |
C1Aa—C2A | 1.375 (5) | C5—H5A | 0.9900 |
C2Aa—H2A | 0.9500 | C5—H5B | 0.9900 |
S1Bb—C1B | 1.757 (11) | C5—C6 | 1.4929 (13) |
C1Bb—H1B | 0.9500 | C6—N3 | 1.3077 (13) |
C1Bb—C2B | 1.478 (12) | C6—N2 | 1.3745 (12) |
C2Bb—H2B | 0.9500 | N3—N4 | 1.3842 (11) |
C2Aa—C3 | 1.431 (3) | N4—H4 | 0.889 (17) |
C2Bb—C3 | 1.357 (11) | N4—C7 | 1.3356 (12) |
S1Aa—C4A | 1.665 (5) | C7—N2 | 1.3689 (12) |
C4Aa—H4A | 0.9500 | C7—S2 | 1.6900 (10) |
S1Bb—C4B | 1.707 (11) | N2—N1 | 1.4021 (11) |
C4Bb—H4B | 0.9500 | N1—H1C | 0.909 (15) |
C3—C4A | 1.394 (5) | N1—H1D | 0.849 (17) |
C2Aa—C1Aa—S1A | 110.3 (3) | C3—C2Bb—H2B | 123.2 |
C4Aa—S1Aa—C1A | 92.56 (19) | C3—C5—H5B | 109.5 |
C2Aa—C1Aa—H1A | 124.8 | H5A—C5—H5B | 108.1 |
S1Aa—C1Aa—H1A | 124.8 | C3—C4Aa—H4A | 123.7 |
C1Aa—C2Aa—H2A | 123.9 | C3—C4Bb—H4B | 122.0 |
C2Bb—C1Bb—S1B | 107.9 (7) | C6—C5—C3 | 110.59 (8) |
C4Bb—S1Bb—C1B | 90.4 (5) | C6—C5—H5A | 109.5 |
S1Bb—C1Bb—H1B | 126.1 | C6—C5—H5B | 109.5 |
C2Bb—C1Bb—H1B | 126.1 | N3—C6—C5 | 126.34 (9) |
C1Bb—C2Bb—H2B | 123.2 | N3—C6—N2 | 110.46 (8) |
C1Aa—C2Aa—C3 | 112.2 (3) | N2—C6—C5 | 123.07 (9) |
S1Aa—C4Aa—H4A | 123.7 | C6—N3—N4 | 103.94 (8) |
S1Bb—C4Bb—H4B | 122.0 | N3—N4—H4 | 122.3 (11) |
C4Aa—C3—C2A | 112.3 (3) | C7—N4—N3 | 113.41 (8) |
C4Bb—C3—C2B | 112.1 (6) | C7—N4—H4 | 124.3 (11) |
C4Aa—C3—C5 | 123.1 (2) | N4—C7—N2 | 103.39 (8) |
C2Aa—C3—C5 | 124.6 (2) | N4—C7—S2 | 130.50 (8) |
C2Bb—C3—C5 | 122.9 (4) | N2—C7—S2 | 126.10 (7) |
C4Bb—C3—C5 | 124.8 (4) | C6—N2—N1 | 124.07 (8) |
C3—C5—H5A | 109.5 | C7—N2—C6 | 108.79 (8) |
C3—C4Aa—S1A | 112.6 (3) | C7—N2—N1 | 127.13 (8) |
C3—C2Aa—H2A | 123.9 | N2—N1—H1C | 108.7 (9) |
C3—C4Bb—S1B | 115.9 (7) | N2—N1—H1D | 106.5 (11) |
C3—C2Bb—C1B | 113.6 (7) | H1C—N1—H1D | 109.7 (14) |
C4Aa—S1Aa—C1Aa—C2Aa | 0.5 (5) | C2Aa—C3—C5—C6 | 89.6 (3) |
S1Aa—C1Aa—C2Aa—C3 | −0.2 (6) | C3—C5—C6—N3 | 93.21 (12) |
C4Bb—S1Bb—C1Bb—C2Bb | −2.2 (12) | C3—C5—C6—N2 | −82.26 (11) |
S1Bb—C1Bb—C2Bb—C3 | 2.7 (17) | N2—C6—N3—N4 | 0.31 (11) |
C1Bb—C2Bb—C3—C4Bb | −1.8 (18) | C5—C6—N3—N4 | −175.64 (9) |
C1Bb—C2Bb—C3—C5 | 174.8 (8) | C6—N3—N4—C7 | −0.17 (11) |
C1Aa—C2Aa—C3—C4Aa | −0.3 (6) | N3—N4—C7—N2 | −0.04 (11) |
C1Aa—C2Aa—C3—C5 | −177.5 (3) | N3—N4—C7—S2 | 179.78 (8) |
C2Aa—C3—C4Aa—S1Aa | 0.7 (7) | N4—C7—N2—C6 | 0.23 (10) |
C5—C3—C4Aa—S1Aa | 178.0 (2) | S2—C7—N2—C6 | −179.61 (7) |
C1Aa—S1Aa—C4Aa—C3 | −0.7 (5) | N4—C7—N2—N1 | −178.40 (9) |
C2Bb—C3—C4Bb—S1Bb | 0.0 (16) | S2—C7—N2—N1 | 1.77 (14) |
C5—C3—C4Bb—S1Bb | −176.6 (5) | N3—C6—N2—C7 | −0.36 (11) |
C1Bb—S1Bb—C4Bb—C3 | 1.4 (12) | C5—C6—N2—C7 | 175.75 (9) |
C4Bb—C3—C5—C6 | 87.4 (9) | N3—C6—N2—N1 | 178.32 (9) |
C2Bb—C3—C5—C6 | −88.8 (10) | C5—C6—N2—N1 | −5.57 (14) |
C4Aa—C3—C5—C6 | −87.3 (4) |
Cg3 is the centroid of the N2/N3/N4/C6/C7 ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1C···N3i | 0.909 (15) | 2.622 (15) | 3.3847 (13) | 142.0 (12) |
N1—H1D···S2ii | 0.849 (17) | 2.628 (16) | 3.4163 (9) | 154.9 (13) |
N4—H4···S2iii | 0.890 (16) | 2.395 (15) | 3.2847 (9) | 178.2 (12) |
C1B—H1B···Cg3iv | 0.95 | 2.78 | 3.503 (11) | 134 |
Symmetry codes: (i) x−1/2, −y+1/2, z−1/2; (ii) −x+1, −y+2, −z+1; (iii) −x, −y+2, −z+1; (iv) −x+1, −y+2, −z. |
Funding information
Funding for this research was provided by: VLIR–UOS (project No. ZEIN2014Z18 to LVM).
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