organic compounds
4-Amino-1H-1,2,4-triazol-1-ium nitrate
aDepartment of Inorganic Chemistry, Faculty of Science, Charles University in Prague, Hlavova 2030, 128 40 Prague 2, Czech Republic, and bDepartment of Spectroscopy, J. Heyrovský Institute of Physical Chemistry, ASCR, v.v.i., Dolejškova 3, 182 23 Prague 8, Czech Republic
*Correspondence e-mail: irena.mat@atlas.cz
The non-centrosymmetric 2H5N4+·NO3−, is based on alternating layers of 4-amino-1H-1,2,4-triazolinium cations (formed by parallel chains of cations mediated by weak C—H⋯N hydrogen bonds) and nitrate anions interconnected via linear and bifurcated N—H⋯O hydrogen bonds and weak C—H⋯O hydrogen bonds. N—H⋯N hydrogen bonds link the anions and cations.
of the novel semi-organic title compound, CRelated literature
For the uses of triazole complexes in medicine, see: Li et al. (2004); Komeda et al. (2003); Mernari et al. (1998); Bentiss et al. (1999). For the triazole moiety as a part of the ligand system in metal complexes, see: Sinditskii et al. (1987); Haasnoot (2000); Klingele & Brooker (2003); Beckmann & Brooker (2003); Muller et al. (2003). For the non-linear optical properties of 4-amino-1,2,4-triazole or 3-amino-1,2,4-triazoles, see: Matulková et al. (2007, 2008). For the preparation of 4-amino-1,2,4-triazole, see: Herbert & Garrison (1953); Matulková et al. (2008); Sanz et al. (2002).
Experimental
Crystal data
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Data collection
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Refinement
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Data collection: COLLECT (Hooft, 1998) and DENZO (Otwinowski & Minor, 1997); cell COLLECT and DENZO; data reduction: COLLECT and DENZO; program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97.
Supporting information
https://doi.org/10.1107/S1600536810049949/zq2079sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810049949/zq2079Isup2.hkl
4-Amino-1,2,4-triazole was prepared and purified by a slightly modified procedure described previously in the literature (Sanz et al., 2002; Herbert et al., 1953; Matulková et al., 2008). The crystals of the title compound, were obtained from a solution of 0.1 g of 4-amino-1,2,4-triazole, 0.8 ml of 2 mol/dm3 nitric acid (68% p.a., Lachema) and 5 ml of water. The solution was left to crystallize at room temperature for several weeks. The colourless crystals obtained were filtered off, washed with methanol and dried in vacuum desiccator over KOH.
H atoms attached to C atoms were calculated in geometrically idealized positions, with C(sp2)—H = 0.93 Å. The positions of H atoms attached to O and N atoms were localized on difference Fourier maps. All hydrogen atoms were constrained to ride on their parent atoms during
with Uiso(H) = 1.2 Ueq (pivot atom).The 1,2,4-triazole moiety as a part of ligand system in metal complexes has gained considerable attention in recent years (Sinditskii et al., 1987; Haasnoot, 2000; Klingele & Brooker, 2003; Beckmann & Brooker, 2003; Muller et al., 2003). The application of triazole ligand lies in the medical research – complex with PtII (Komeda et al., 2003) exhibits antitumor activity. Triazole derivatives are also used in the synthesis of antibiotics, fungicides, herbicides, plant growth hormone regulators (Li et al., 2004), and potentially prospective corrosion inhibitors (Mernari et al., 1998; Bentiss et al., 1999).
Materials based on triazole compounds with dicarboxylic acids (4-amino-1,2,4-triazol-1-ium hydrogen oxalate, adducts of 4-amino-1,2,4-triazole with succinic acid and adipic acid and 3-amino-1,2,4-triazolinium hydrogen L-tartrate) were also prepared and characterized as promising compounds in the field of non-linear optics (Matulková et al., 2008; Matulková et al., 2007).
The non-centrosymmetric
of the title compound is based on alternating layers of 4-amino-1,2,4-triazolinium cations (formed by parallel chains of cations mediated by weak C—H···N hydrogen bonds) and nitrate anions inter-connected via linear and bifurcated N—H···O hydrogen bonds and weak C—H···O hydrogen bond. The donor···acceptor distances in these hydrogen bonds attain values from 2.710 (2) to 3.167 (3) Å (N—H···O bonds) and 3.398 (3) Å (C—H···O bond). The Fig. 1 contains atom-labelling of title compound and packing scheme of the is presented in Fig. 2.The bond length comparison of 4-amino-1,2,4-triazolinium cations in the title compound and 4-amino-1,2,4-triazol-1-ium hydrogen oxalate (Matulková et al., 2008) exhibits reasonable shortening of N1—N2 distance in the cation of the title compound compared to N2—N3 distance in the organic salt (1.359 (2) Å for 4-amino-1,2,4-triazol-1-ium nitrate; 1.366 (2) Å for 4-amino-1,2,4-triazol-1-ium hydrogen oxalate).
The nitrate anions are planar with O—N—O angles slightly different from theoretical values of 120° in the
of the title compound. These differences can be explained by unequal participation of oxygen atoms in N—H···O hydrogen bonds. The smaller angle values 119.7 (2) and 118.5 (2)° (i.e. angles O1—N7—O2 and O3—N7—O1) are connected with the existence of bifurcated hydrogen bonds influencing these parts of the anion. The remaining bond angle O2—N7—O3 shows a value of 121.8 (2)°. Similar differences can be also observed in the case of N—O bond distances - i.e. two short distances 1.232 (3) and 1.240 (2) Å (N7—O2 and N7—O3, respectively) and a longer one 1.263 (2) Å (N7—O1).For the uses of triazole complexes in medicine, see: Li et al. (2004); Komeda et al. (2003); Mernari et al. (1998); Bentiss et al. (1999). For the triazole moiety as a part of the ligand system in metal complexes, see: Sinditskii et al. (1987); Haasnoot (2000); Klingele & Brooker (2003); Beckmann & Brooker (2003); Muller et al. (2003). For the non-linear optical properties of 4-amino-1,2,4-triazole or 3-amino-1,2,4-triazoles, see: Matulková et al. (2007, 2008). For the preparation of 4-amino-1,2,4-triazole, see: Herbert & Garrison (1953); Matulková et al. (2008); Sanz et al. (2002).
Data collection: COLLECT (Hooft, 1998) and DENZO (Otwinowski & Minor, 1997); cell
COLLECT (Hooft, 1998) and DENZO (Otwinowski & Minor, 1997); data reduction: COLLECT (Hooft, 1998) and DENZO (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).Fig. 1. The atom-labelling of the title compound. Displacement ellipsoids are drawn at the 50% probability level. | |
Fig. 2. A packing scheme of the title compound (projection to ac plane). Hydrogen bonds are indicated by dashed lines (C—H···O bonds are omitted for clarity). |
C2H5N4+·NO3− | F(000) = 304 |
Mr = 147.11 | Dx = 1.629 Mg m−3 |
Monoclinic, Cc | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: C -2yc | Cell parameters from 572 reflections |
a = 9.6200 (9) Å | θ = 1.0–27.5° |
b = 5.2790 (3) Å | µ = 0.15 mm−1 |
c = 11.895 (1) Å | T = 293 K |
β = 96.667 (3)° | Prism, colourless |
V = 599.99 (8) Å3 | 0.5 × 0.4 × 0.35 mm |
Z = 4 |
Nonius KappaCCD area-detector diffractometer | 650 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.026 |
Graphite monochromator | θmax = 27.5°, θmin = 3.5° |
Detector resolution: 9.091 pixels mm-1 | h = −11→12 |
φ and ω scans to fill the Ewald sphere | k = −5→6 |
1867 measured reflections | l = −15→15 |
685 independent reflections |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.027 | H-atom parameters constrained |
wR(F2) = 0.073 | w = 1/[σ2(Fo2) + (0.0382P)2 + 0.111P] where P = (Fo2 + 2Fc2)/3 |
S = 1.11 | (Δ/σ)max < 0.001 |
685 reflections | Δρmax = 0.12 e Å−3 |
92 parameters | Δρmin = −0.14 e Å−3 |
2 restraints | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.104 (8) |
C2H5N4+·NO3− | V = 599.99 (8) Å3 |
Mr = 147.11 | Z = 4 |
Monoclinic, Cc | Mo Kα radiation |
a = 9.6200 (9) Å | µ = 0.15 mm−1 |
b = 5.2790 (3) Å | T = 293 K |
c = 11.895 (1) Å | 0.5 × 0.4 × 0.35 mm |
β = 96.667 (3)° |
Nonius KappaCCD area-detector diffractometer | 650 reflections with I > 2σ(I) |
1867 measured reflections | Rint = 0.026 |
685 independent reflections |
R[F2 > 2σ(F2)] = 0.027 | 2 restraints |
wR(F2) = 0.073 | H-atom parameters constrained |
S = 1.11 | Δρmax = 0.12 e Å−3 |
685 reflections | Δρmin = −0.14 e Å−3 |
92 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
N1 | 0.20255 (19) | 0.8902 (4) | 0.36897 (16) | 0.0454 (5) | |
N2 | 0.08599 (18) | 0.8575 (3) | 0.42181 (14) | 0.0378 (4) | |
H2 | 0.0630 | 0.9678 | 0.4730 | 0.045* | |
C3 | 0.0132 (2) | 0.6606 (4) | 0.38252 (16) | 0.0370 (4) | |
H3 | −0.0698 | 0.6022 | 0.4062 | 0.044* | |
N4 | 0.08113 (16) | 0.5606 (3) | 0.30229 (14) | 0.0337 (4) | |
C5 | 0.1957 (2) | 0.7065 (5) | 0.29519 (19) | 0.0436 (5) | |
H5 | 0.2608 | 0.6793 | 0.2444 | 0.052* | |
N6 | 0.0325 (2) | 0.3489 (3) | 0.23683 (17) | 0.0424 (4) | |
H6A | 0.1058 | 0.2463 | 0.2131 | 0.051* | |
H6B | −0.0266 | 0.4027 | 0.1716 | 0.051* | |
N7 | 0.37711 (17) | 0.3656 (4) | 0.08773 (13) | 0.0383 (4) | |
O1 | 0.49649 (17) | 0.2961 (4) | 0.06543 (15) | 0.0563 (5) | |
O2 | 0.3276 (2) | 0.5676 (3) | 0.04961 (17) | 0.0555 (5) | |
O3 | 0.31256 (18) | 0.2262 (4) | 0.14762 (15) | 0.0566 (5) |
U11 | U22 | U33 | U12 | U13 | U23 | |
N1 | 0.0350 (9) | 0.0525 (10) | 0.0509 (10) | −0.0089 (8) | 0.0142 (8) | −0.0060 (8) |
N2 | 0.0347 (8) | 0.0442 (9) | 0.0359 (8) | −0.0036 (7) | 0.0096 (6) | −0.0009 (7) |
C3 | 0.0324 (10) | 0.0446 (11) | 0.0350 (9) | −0.0038 (8) | 0.0088 (7) | 0.0027 (8) |
N4 | 0.0301 (8) | 0.0366 (9) | 0.0346 (7) | −0.0019 (6) | 0.0052 (6) | 0.0008 (6) |
C5 | 0.0345 (10) | 0.0488 (12) | 0.0497 (12) | −0.0039 (9) | 0.0147 (9) | −0.0048 (9) |
N6 | 0.0425 (10) | 0.0374 (9) | 0.0472 (9) | −0.0025 (7) | 0.0049 (7) | −0.0050 (7) |
N7 | 0.0354 (10) | 0.0448 (10) | 0.0354 (8) | 0.0046 (7) | 0.0067 (7) | −0.0015 (7) |
O1 | 0.0444 (10) | 0.0686 (11) | 0.0597 (10) | 0.0175 (9) | 0.0221 (8) | 0.0214 (8) |
O2 | 0.0570 (10) | 0.0488 (10) | 0.0627 (10) | 0.0157 (8) | 0.0152 (8) | 0.0068 (8) |
O3 | 0.0458 (9) | 0.0649 (11) | 0.0623 (11) | 0.0013 (9) | 0.0202 (8) | 0.0160 (9) |
N1—C5 | 1.304 (3) | N4—N6 | 1.411 (2) |
N1—N2 | 1.359 (2) | C5—H5 | 0.9300 |
N2—C3 | 1.309 (3) | N6—H6A | 0.9572 |
N2—H2 | 0.8888 | N6—H6B | 0.9506 |
C3—N4 | 1.327 (3) | N7—O2 | 1.232 (3) |
C3—H3 | 0.9300 | N7—O3 | 1.240 (2) |
N4—C5 | 1.355 (3) | N7—O1 | 1.263 (2) |
C5—N1—N2 | 103.71 (17) | N1—C5—N4 | 111.00 (18) |
C3—N2—N1 | 111.81 (18) | N1—C5—H5 | 124.5 |
C3—N2—H2 | 126.9 | N4—C5—H5 | 124.5 |
N1—N2—H2 | 121.2 | N4—N6—H6A | 113.8 |
N2—C3—N4 | 106.57 (17) | N4—N6—H6B | 110.0 |
N2—C3—H3 | 126.7 | H6A—N6—H6B | 108.6 |
N4—C3—H3 | 126.7 | O2—N7—O3 | 121.80 (19) |
C3—N4—C5 | 106.89 (17) | O2—N7—O1 | 119.72 (19) |
C3—N4—N6 | 123.56 (17) | O3—N7—O1 | 118.48 (19) |
C5—N4—N6 | 129.48 (18) |
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H2···O1i | 0.89 | 1.83 | 2.710 (2) | 173 |
N2—H2···N7i | 0.89 | 2.53 | 3.315 (2) | 148 |
N2—H2···O2i | 0.89 | 2.54 | 3.086 (2) | 120 |
N6—H6A···O3 | 0.96 | 2.22 | 3.077 (3) | 148 |
N6—H6B···O3ii | 0.95 | 2.30 | 3.008 (3) | 131 |
N6—H6B···O1ii | 0.95 | 2.45 | 3.112 (3) | 126 |
N6—H6B···O2iii | 0.95 | 2.59 | 3.167 (3) | 119 |
C3—H3···N1iii | 0.93 | 2.45 | 3.299 (3) | 151 |
C5—H5···O2 | 0.93 | 2.55 | 3.398 (3) | 153 |
Symmetry codes: (i) x−1/2, −y+3/2, z+1/2; (ii) x−1/2, y+1/2, z; (iii) x−1/2, y−1/2, z. |
Experimental details
Crystal data | |
Chemical formula | C2H5N4+·NO3− |
Mr | 147.11 |
Crystal system, space group | Monoclinic, Cc |
Temperature (K) | 293 |
a, b, c (Å) | 9.6200 (9), 5.2790 (3), 11.895 (1) |
β (°) | 96.667 (3) |
V (Å3) | 599.99 (8) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.15 |
Crystal size (mm) | 0.5 × 0.4 × 0.35 |
Data collection | |
Diffractometer | Nonius KappaCCD area-detector |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 1867, 685, 650 |
Rint | 0.026 |
(sin θ/λ)max (Å−1) | 0.650 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.027, 0.073, 1.11 |
No. of reflections | 685 |
No. of parameters | 92 |
No. of restraints | 2 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.12, −0.14 |
Computer programs: COLLECT (Hooft, 1998) and DENZO (Otwinowski & Minor, 1997), SIR92 (Altomare et al., 1994), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H2···O1i | 0.89 | 1.83 | 2.710 (2) | 173. |
N2—H2···N7i | 0.89 | 2.53 | 3.315 (2) | 148. |
N2—H2···O2i | 0.89 | 2.54 | 3.086 (2) | 120. |
N6—H6A···O3 | 0.96 | 2.22 | 3.077 (3) | 148. |
N6—H6B···O3ii | 0.95 | 2.30 | 3.008 (3) | 131. |
N6—H6B···O1ii | 0.95 | 2.45 | 3.112 (3) | 126. |
N6—H6B···O2iii | 0.95 | 2.59 | 3.167 (3) | 119. |
C3—H3···N1iii | 0.93 | 2.45 | 3.299 (3) | 151. |
C5—H5···O2 | 0.93 | 2.55 | 3.398 (3) | 153. |
Symmetry codes: (i) x−1/2, −y+3/2, z+1/2; (ii) x−1/2, y+1/2, z; (iii) x−1/2, y−1/2, z. |
Acknowledgements
This work was supported financially by the Czech Science Foundation (grant No. 203/09/0878) and is part of the Long-term Research Plan of the Ministry of Education of the Czech Republic (No. MSM 0021620857).
References
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The 1,2,4-triazole moiety as a part of ligand system in metal complexes has gained considerable attention in recent years (Sinditskii et al., 1987; Haasnoot, 2000; Klingele & Brooker, 2003; Beckmann & Brooker, 2003; Muller et al., 2003). The application of triazole ligand lies in the medical research – complex with PtII (Komeda et al., 2003) exhibits antitumor activity. Triazole derivatives are also used in the synthesis of antibiotics, fungicides, herbicides, plant growth hormone regulators (Li et al., 2004), and potentially prospective corrosion inhibitors (Mernari et al., 1998; Bentiss et al., 1999).
Materials based on triazole compounds with dicarboxylic acids (4-amino-1,2,4-triazol-1-ium hydrogen oxalate, adducts of 4-amino-1,2,4-triazole with succinic acid and adipic acid and 3-amino-1,2,4-triazolinium hydrogen L-tartrate) were also prepared and characterized as promising compounds in the field of non-linear optics (Matulková et al., 2008; Matulková et al., 2007).
The non-centrosymmetric crystal structure of the title compound is based on alternating layers of 4-amino-1,2,4-triazolinium cations (formed by parallel chains of cations mediated by weak C—H···N hydrogen bonds) and nitrate anions inter-connected via linear and bifurcated N—H···O hydrogen bonds and weak C—H···O hydrogen bond. The donor···acceptor distances in these hydrogen bonds attain values from 2.710 (2) to 3.167 (3) Å (N—H···O bonds) and 3.398 (3) Å (C—H···O bond). The Fig. 1 contains atom-labelling of title compound and packing scheme of the crystal structure is presented in Fig. 2.
The bond length comparison of 4-amino-1,2,4-triazolinium cations in the title compound and 4-amino-1,2,4-triazol-1-ium hydrogen oxalate (Matulková et al., 2008) exhibits reasonable shortening of N1—N2 distance in the cation of the title compound compared to N2—N3 distance in the organic salt (1.359 (2) Å for 4-amino-1,2,4-triazol-1-ium nitrate; 1.366 (2) Å for 4-amino-1,2,4-triazol-1-ium hydrogen oxalate).
The nitrate anions are planar with O—N—O angles slightly different from theoretical values of 120° in the crystal structure of the title compound. These differences can be explained by unequal participation of oxygen atoms in N—H···O hydrogen bonds. The smaller angle values 119.7 (2) and 118.5 (2)° (i.e. angles O1—N7—O2 and O3—N7—O1) are connected with the existence of bifurcated hydrogen bonds influencing these parts of the anion. The remaining bond angle O2—N7—O3 shows a value of 121.8 (2)°. Similar differences can be also observed in the case of N—O bond distances - i.e. two short distances 1.232 (3) and 1.240 (2) Å (N7—O2 and N7—O3, respectively) and a longer one 1.263 (2) Å (N7—O1).