organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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3-Nitro-1H-1,2,4-triazole

aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
*Correspondence e-mail: hkfun@usm.my

(Received 22 November 2010; accepted 25 November 2010; online 4 December 2010)

The asymmetric unit of the title compound, C2H2N4O2, contains two crystallographically independent mol­ecules in which the triazole rings are essentially planar, with maximum deviations of 0.003 (1) Å in both molecules. The dihedral angle between the two 1H-1,2,4-triazole rings is 56.58 (5)°. In the crystal, mol­ecules are linked via inter­molecular N—H⋯N and C—H⋯O hydrogen bonds, forming a supra­molecular chain along the b axis.

Related literature

For details and applications of 1H-1,2,4-triazole derivatives, see: Desenko (1995[Desenko, S. M. (1995). Khim. Geterotsikl. Soedin. pp. 2-24.]); Vos et al. (1983[Vos, G., le Febre, R. A., de Graaff, R. A. G., Haasnoot, J. G. & Reedijk, J. (1983). J. Am. Chem. Soc. 105, 1682-1683.]); van Albada et al. (1984[Albada, G. A. van, de Graaff, R. A. G., Haasnoot, J. G. & Reedijk, J. (1984). Inorg. Chem. 23, 1404-1408.]); Al-Kharafi et al. (1986[Al-Kharafi, F. M., Al-Hajjar, F. H. & Katrib, A. (1986). Corros. Sci. 26, 257-264.]); Gupta & Bhargava (1978[Gupta, A. K. & Bhargava, K. P. (1978). Pharmazie, 33, 430-431.]); Jones et al. (1965[Jones, D. H., Slack, R., Squires, S. & Wooldridge, K. R. H. (1965). J. Med. Chem. 8, 676-680.]); Bennur et al. (1976[Bennur, S. C., Jigajinni, V. B. & Badiger, V. V. (1976). Rev. Roum. Chim. 21, 757-762.]). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986[Cosier, J. & Glazer, A. M. (1986). J. Appl. Cryst. 19, 105-107.]).

[Scheme 1]

Experimental

Crystal data
  • C2H2N4O2

  • Mr = 114.08

  • Monoclinic, P 21 /c

  • a = 8.7818 (1) Å

  • b = 10.0726 (2) Å

  • c = 9.9703 (1) Å

  • β = 107.081 (1)°

  • V = 843.03 (2) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.16 mm−1

  • T = 100 K

  • 0.48 × 0.33 × 0.30 mm

Data collection
  • Bruker SMART APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.928, Tmax = 0.954

  • 11450 measured reflections

  • 3081 independent reflections

  • 2768 reflections with I > 2σ(I)

  • Rint = 0.022

Refinement
  • R[F2 > 2σ(F2)] = 0.035

  • wR(F2) = 0.092

  • S = 1.05

  • 3081 reflections

  • 153 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.50 e Å−3

  • Δρmin = −0.40 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N2A—H1N1⋯N1Ai 0.885 (15) 1.995 (15) 2.8540 (9) 163.4 (15)
N2B—H1N2⋯N1Bii 0.857 (16) 2.057 (16) 2.9128 (10) 176.0 (16)
C1A—H1AA⋯O2Aiii 0.93 2.50 3.1129 (10) 124
C1B—H1BA⋯O2Bii 0.93 2.51 3.0451 (11) 117
Symmetry codes: (i) [x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]; (ii) [-x+1, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]; (iii) [-x+2, y+{\script{1\over 2}}, -z+{\script{3\over 2}}].

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

1H-1,2,4-Triazole ring systems are typical planar six-π-electron partially aromatic systems, and are used, along with their derivatives, as starting materials for the synthesis of many heterocycles (Desenko, 1995). Substituted 1H-1,2,4-triazoles have also been actively studied as bridging ligands coordinating through their vicinal N atoms and some have special structures with interesting magnetic properties (Vos et al., 1983; van Albada et al., 1984). Studies also indicate that the 1H-1,2,4-triazole system is associated with anticorrosion (Al-Kharafi et al., 1986) and anti-inflammatory action (Gupta & Bhargava, 1978) and other pharmacological activities by exhibiting antiviral, anti-asthmatic, diuretic, analgesic, antimicrobial, antidepressant and antifungal effects (Jones et al., 1965; Bennur et al., 1976).

The asymmetric unit of the title compound consists of two crystallographically independent 3-nitro-1H-1,2,4-triazole molecules (A & B) with very similar geometry (Fig. 1). The 1H-1,2,4-triazole units are essentially planar with maximum deviations of 0.003 (1) Å for atom N1A (molecule A) and 0.003 (1) Å for atom C2B (molecule B). The dihedral angle between the two 1H-1,2,4-triazole (N1A—N3A/ C1A–C2A) and (N1B—N3B/C1B–C2B) rings is 56.58 (5)°.

In the crystal structure (Fig. 2), molecules are connected via N2A—H1N1···N1A, N2B—H1N2···N1B, C1A—H1AA···O2A and C1B—H1BA···O2B (Table 1) hydrogen bonds to form a one-dimensional supramolecular chain along the b-axis.

Related literature top

For details and applications of 1H-1,2,4-triazole derivatives, see: Desenko (1995); Vos et al. (1983); van Albada et al. (1984); Al-Kharafi et al. (1986); Gupta & Bhargava (1978); Jones et al. (1965); Bennur et al. (1976). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986).

Experimental top

Hot methanol solution (20 ml) of 3-nitro-1H-1,2,4-triazole (57 mg, Aldrich) was warmed over a heating magnetic stirrer for 5 minutes. The resulting solution was allowed to cool slowly at room temperature. Crystals of the title compound appeared from the mother liquor after a few days.

Refinement top

Atoms H1N1 and H1N2 were located from a difference Fourier map and refined freely [refined N—H distances 0.857 (16) and 0.885 (15) Å]. The remaining H atoms were positioned geometrically [C—H = 0.93 Å] and were refined using a riding model, with Uiso(H) = 1.2 Ueq(C).

Structure description top

1H-1,2,4-Triazole ring systems are typical planar six-π-electron partially aromatic systems, and are used, along with their derivatives, as starting materials for the synthesis of many heterocycles (Desenko, 1995). Substituted 1H-1,2,4-triazoles have also been actively studied as bridging ligands coordinating through their vicinal N atoms and some have special structures with interesting magnetic properties (Vos et al., 1983; van Albada et al., 1984). Studies also indicate that the 1H-1,2,4-triazole system is associated with anticorrosion (Al-Kharafi et al., 1986) and anti-inflammatory action (Gupta & Bhargava, 1978) and other pharmacological activities by exhibiting antiviral, anti-asthmatic, diuretic, analgesic, antimicrobial, antidepressant and antifungal effects (Jones et al., 1965; Bennur et al., 1976).

The asymmetric unit of the title compound consists of two crystallographically independent 3-nitro-1H-1,2,4-triazole molecules (A & B) with very similar geometry (Fig. 1). The 1H-1,2,4-triazole units are essentially planar with maximum deviations of 0.003 (1) Å for atom N1A (molecule A) and 0.003 (1) Å for atom C2B (molecule B). The dihedral angle between the two 1H-1,2,4-triazole (N1A—N3A/ C1A–C2A) and (N1B—N3B/C1B–C2B) rings is 56.58 (5)°.

In the crystal structure (Fig. 2), molecules are connected via N2A—H1N1···N1A, N2B—H1N2···N1B, C1A—H1AA···O2A and C1B—H1BA···O2B (Table 1) hydrogen bonds to form a one-dimensional supramolecular chain along the b-axis.

For details and applications of 1H-1,2,4-triazole derivatives, see: Desenko (1995); Vos et al. (1983); van Albada et al. (1984); Al-Kharafi et al. (1986); Gupta & Bhargava (1978); Jones et al. (1965); Bennur et al. (1976). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The asymmetric unit of the title compound. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. The crystal packing of the title compound, showing a hydrogen-bonded (dashed lines) molecular chain.
3-Nitro-1H-1,2,4-triazole top
Crystal data top
C2H2N4O2F(000) = 464
Mr = 114.08Dx = 1.798 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 7180 reflections
a = 8.7818 (1) Åθ = 2.9–32.6°
b = 10.0726 (2) ŵ = 0.16 mm1
c = 9.9703 (1) ÅT = 100 K
β = 107.081 (1)°Block, colourless
V = 843.03 (2) Å30.48 × 0.33 × 0.30 mm
Z = 8
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
3081 independent reflections
Radiation source: fine-focus sealed tube2768 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.022
φ and ω scansθmax = 32.7°, θmin = 2.9°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
h = 1311
Tmin = 0.928, Tmax = 0.954k = 1513
11450 measured reflectionsl = 1515
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.035Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.092H atoms treated by a mixture of independent and constrained refinement
S = 1.05 w = 1/[σ2(Fo2) + (0.0495P)2 + 0.2412P]
where P = (Fo2 + 2Fc2)/3
3081 reflections(Δ/σ)max = 0.001
153 parametersΔρmax = 0.50 e Å3
0 restraintsΔρmin = 0.40 e Å3
Crystal data top
C2H2N4O2V = 843.03 (2) Å3
Mr = 114.08Z = 8
Monoclinic, P21/cMo Kα radiation
a = 8.7818 (1) ŵ = 0.16 mm1
b = 10.0726 (2) ÅT = 100 K
c = 9.9703 (1) Å0.48 × 0.33 × 0.30 mm
β = 107.081 (1)°
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
3081 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
2768 reflections with I > 2σ(I)
Tmin = 0.928, Tmax = 0.954Rint = 0.022
11450 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0350 restraints
wR(F2) = 0.092H atoms treated by a mixture of independent and constrained refinement
S = 1.05Δρmax = 0.50 e Å3
3081 reflectionsΔρmin = 0.40 e Å3
153 parameters
Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O1A0.73082 (8)0.04055 (7)0.51717 (7)0.01914 (13)
O2A0.85716 (9)0.01680 (7)0.73151 (6)0.01888 (14)
N1A1.01266 (8)0.21389 (7)0.64087 (7)0.01307 (13)
N2A0.99857 (9)0.24376 (7)0.42001 (7)0.01273 (13)
N3A0.89747 (8)0.14183 (7)0.41773 (7)0.01286 (13)
N4A0.82618 (9)0.02813 (7)0.60358 (7)0.01348 (13)
C1A1.06543 (10)0.28585 (8)0.55150 (8)0.01356 (14)
H1AA1.13810.35520.57680.016*
C2A0.91199 (9)0.13008 (8)0.55271 (8)0.01167 (14)
O1B0.75840 (8)0.41600 (7)0.50676 (7)0.02046 (14)
O2B0.68377 (9)0.58439 (6)0.60867 (7)0.01985 (14)
N1B0.51771 (8)0.42579 (7)0.73353 (7)0.01312 (13)
N2B0.51813 (9)0.20833 (7)0.72132 (7)0.01419 (13)
N3B0.60998 (9)0.24714 (7)0.64058 (7)0.01375 (13)
N4B0.68913 (8)0.46461 (7)0.58504 (7)0.01361 (13)
C1B0.46484 (10)0.31423 (8)0.77581 (8)0.01436 (15)
H1BA0.40020.31020.83470.017*
C2B0.60451 (9)0.37710 (8)0.65365 (8)0.01189 (14)
H1N11.0120 (19)0.2722 (16)0.3403 (16)0.034 (4)*
H1N20.5028 (18)0.1259 (16)0.7343 (15)0.030 (4)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O1A0.0195 (3)0.0170 (3)0.0203 (3)0.0044 (2)0.0049 (2)0.0008 (2)
O2A0.0278 (3)0.0179 (3)0.0136 (3)0.0007 (2)0.0102 (2)0.0037 (2)
N1A0.0164 (3)0.0135 (3)0.0103 (3)0.0005 (2)0.0055 (2)0.0003 (2)
N2A0.0164 (3)0.0133 (3)0.0099 (3)0.0001 (2)0.0060 (2)0.0011 (2)
N3A0.0156 (3)0.0128 (3)0.0107 (3)0.0004 (2)0.0048 (2)0.0009 (2)
N4A0.0161 (3)0.0118 (3)0.0144 (3)0.0020 (2)0.0072 (2)0.0018 (2)
C1A0.0163 (3)0.0142 (3)0.0115 (3)0.0007 (3)0.0060 (3)0.0005 (2)
C2A0.0146 (3)0.0109 (3)0.0107 (3)0.0013 (2)0.0056 (2)0.0010 (2)
O1B0.0240 (3)0.0185 (3)0.0245 (3)0.0046 (2)0.0158 (3)0.0025 (2)
O2B0.0264 (3)0.0106 (3)0.0260 (3)0.0006 (2)0.0131 (3)0.0004 (2)
N1B0.0151 (3)0.0111 (3)0.0143 (3)0.0010 (2)0.0062 (2)0.0004 (2)
N2B0.0178 (3)0.0101 (3)0.0161 (3)0.0002 (2)0.0072 (2)0.0006 (2)
N3B0.0163 (3)0.0111 (3)0.0149 (3)0.0009 (2)0.0062 (2)0.0007 (2)
N4B0.0144 (3)0.0119 (3)0.0153 (3)0.0015 (2)0.0055 (2)0.0018 (2)
C1B0.0166 (3)0.0119 (3)0.0160 (3)0.0006 (3)0.0070 (3)0.0005 (2)
C2B0.0128 (3)0.0103 (3)0.0127 (3)0.0007 (2)0.0041 (2)0.0007 (2)
Geometric parameters (Å, º) top
O1A—N4A1.2241 (10)O1B—N4B1.2239 (9)
O2A—N4A1.2289 (9)O2B—N4B1.2329 (9)
N1A—C1A1.3329 (10)N1B—C1B1.3307 (10)
N1A—C2A1.3455 (10)N1B—C2B1.3462 (10)
N2A—C1A1.3383 (10)N2B—C1B1.3421 (10)
N2A—N3A1.3531 (10)N2B—N3B1.3539 (9)
N2A—H1N10.885 (15)N2B—H1N20.857 (16)
N3A—C2A1.3194 (9)N3B—C2B1.3178 (10)
N4A—C2A1.4506 (10)N4B—C2B1.4476 (10)
C1A—H1AA0.9300C1B—H1BA0.9300
C1A—N1A—C2A101.26 (6)C1B—N1B—C2B100.99 (7)
C1A—N2A—N3A110.72 (6)C1B—N2B—N3B110.52 (7)
C1A—N2A—H1N1129.9 (10)C1B—N2B—H1N2128.3 (10)
N3A—N2A—H1N1119.4 (10)N3B—N2B—H1N2121.2 (10)
C2A—N3A—N2A100.64 (6)C2B—N3B—N2B100.52 (6)
O1A—N4A—O2A125.11 (7)O1B—N4B—O2B124.56 (7)
O1A—N4A—C2A118.18 (6)O1B—N4B—C2B118.56 (7)
O2A—N4A—C2A116.70 (7)O2B—N4B—C2B116.86 (6)
N1A—C1A—N2A110.12 (7)N1B—C1B—N2B110.33 (7)
N1A—C1A—H1AA124.9N1B—C1B—H1BA124.8
N2A—C1A—H1AA124.9N2B—C1B—H1BA124.8
N3A—C2A—N1A117.27 (7)N3B—C2B—N1B117.63 (7)
N3A—C2A—N4A121.04 (7)N3B—C2B—N4B121.29 (7)
N1A—C2A—N4A121.66 (6)N1B—C2B—N4B121.08 (7)
C1A—N2A—N3A—C2A0.05 (8)C1B—N2B—N3B—C2B0.10 (9)
C2A—N1A—C1A—N2A0.45 (9)C2B—N1B—C1B—N2B0.54 (9)
N3A—N2A—C1A—N1A0.33 (10)N3B—N2B—C1B—N1B0.30 (10)
N2A—N3A—C2A—N1A0.27 (9)N2B—N3B—C2B—N1B0.49 (9)
N2A—N3A—C2A—N4A178.46 (7)N2B—N3B—C2B—N4B179.31 (7)
C1A—N1A—C2A—N3A0.46 (9)C1B—N1B—C2B—N3B0.66 (9)
C1A—N1A—C2A—N4A178.64 (7)C1B—N1B—C2B—N4B179.14 (7)
O1A—N4A—C2A—N3A5.31 (11)O1B—N4B—C2B—N3B4.58 (12)
O2A—N4A—C2A—N3A173.84 (7)O2B—N4B—C2B—N3B176.50 (8)
O1A—N4A—C2A—N1A176.57 (7)O1B—N4B—C2B—N1B175.62 (8)
O2A—N4A—C2A—N1A4.27 (11)O2B—N4B—C2B—N1B3.29 (11)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2A—H1N1···N1Ai0.885 (15)1.995 (15)2.8540 (9)163.4 (15)
N2B—H1N2···N1Bii0.857 (16)2.057 (16)2.9128 (10)176.0 (16)
C1A—H1AA···O2Aiii0.932.503.1129 (10)124
C1B—H1BA···O2Bii0.932.513.0451 (11)117
Symmetry codes: (i) x, y+1/2, z1/2; (ii) x+1, y1/2, z+3/2; (iii) x+2, y+1/2, z+3/2.

Experimental details

Crystal data
Chemical formulaC2H2N4O2
Mr114.08
Crystal system, space groupMonoclinic, P21/c
Temperature (K)100
a, b, c (Å)8.7818 (1), 10.0726 (2), 9.9703 (1)
β (°) 107.081 (1)
V3)843.03 (2)
Z8
Radiation typeMo Kα
µ (mm1)0.16
Crystal size (mm)0.48 × 0.33 × 0.30
Data collection
DiffractometerBruker SMART APEXII CCD area-detector
Absorption correctionMulti-scan
(SADABS; Bruker, 2009)
Tmin, Tmax0.928, 0.954
No. of measured, independent and
observed [I > 2σ(I)] reflections
11450, 3081, 2768
Rint0.022
(sin θ/λ)max1)0.760
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.035, 0.092, 1.05
No. of reflections3081
No. of parameters153
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.50, 0.40

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2A—H1N1···N1Ai0.885 (15)1.995 (15)2.8540 (9)163.4 (15)
N2B—H1N2···N1Bii0.857 (16)2.057 (16)2.9128 (10)176.0 (16)
C1A—H1AA···O2Aiii0.93002.50003.1129 (10)124.00
C1B—H1BA···O2Bii0.93002.51003.0451 (11)117.00
Symmetry codes: (i) x, y+1/2, z1/2; (ii) x+1, y1/2, z+3/2; (iii) x+2, y+1/2, z+3/2.
 

Footnotes

Thomson Reuters ResearcherID: A-3561-2009.

Acknowledgements

MH and HKF thank the Malaysian Government and Universiti Sains Malaysia for the Research University grant No. 1001/PFIZIK/811160. MH also thanks Universiti Sains Malaysia for a post-doctoral research fellowship.

References

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