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ISSN: 2056-9890

4-Amino-3,5-di-2-pyridyl-4H-1,2,4-triazole

aCEMDRX, Physics Department, University of Coimbra, P-3004-516 Coimbra, Portugal, and bChemistry Department, University of Coimbra, P-3004-516 Coimbra, Portugal
*Correspondence e-mail: manuela@pollux.fis.uc.pt

(Received 5 August 2008; accepted 8 August 2008; online 16 August 2008)

In the crystal structure of the title compound, C12H10N6, the mol­ecules deviate slightly from planarity. The plane of the central triazole ring makes angles of 6.13 (9) and 3.28 (10)° with the pyridyl ring planes. Intra­molecular N—H⋯N inter­actions form six-membered closed rings. The crystal packing also shows weak C—H⋯π and C—H⋯N inter­actions.

Related literature

For related literature, see: Dirtu et al. (2007[Dirtu, M. M., Garcia, Y., Nica, M., Rotaru, A., Linares, J. & Varret, F. (2007). Polyhedron, 26, 2259-2263.]); Faulmann et al. (1990[Faulmann, C., van Koningsbruggen, P. J., de Graaff, R. A. G., Haasnoot, J. G. & Reedijk, J. (1990). Acta Cryst. C46, 2357-2360.]); Haasnoot (2000[Haasnoot, J. G. (2000). Coord. Chem. Rev. 200-202, 131-185.]); van Koningsbruggen et al. (1995[Koningsbruggen, P. J. van, Gatteshi, D., Graaff, R. A. G., Haasnoot, J. G., Reedjik, J. & Zanchini, C. (1995). Inorg. Chem. 34, 5175-5182.]); Malone et al. (1997[Malone, J. F., Murray, C. M., Charlton, M. H., Docherty, R. & Lavery, A. J. (1997). J. Chem. Soc. Faraday Trans. 93, 3429-3436.]), Mernari et al. (1998[Mernari, B., El Azhar, M., El Attari, H., Lagrenée, M. & Pierrot, M. (1998). Acta Cryst. C54, 1983-1986.]).

[Scheme 1]

Experimental

Crystal data
  • C12H10N6

  • Mr = 238.26

  • Monoclinic, P 21 /c

  • a = 6.6191 (2) Å

  • b = 14.7136 (4) Å

  • c = 11.4703 (4) Å

  • β = 95.474 (2)°

  • V = 1112.01 (6) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 293 (2) K

  • 0.20 × 0.13 × 0.12 mm

Data collection
  • Bruker APEX CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2000[Sheldrick, G. M. (2000). SADABS. University of Göttingen, Germany.]) Tmin = 0.91, Tmax = 0.99

  • 23253 measured reflections

  • 2751 independent reflections

  • 1465 reflections with I > 2σ(I)

  • Rint = 0.052

Refinement
  • R[F2 > 2σ(F2)] = 0.045

  • wR(F2) = 0.116

  • S = 1.00

  • 2751 reflections

  • 193 parameters

  • Only H-atom coordinates refined

  • Δρmax = 0.19 e Å−3

  • Δρmin = −0.15 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 and Cg2 are the centroids of the N6/C8–C12 and N5/C3–C7 rings, respectively.

D—H⋯A D—H H⋯A DA D—H⋯A
N4—H4A⋯N6 0.91 (2) 2.08 (2) 2.839 (2) 141.1 (17)
N4—H4B⋯N5 0.87 (2) 2.39 (2) 2.863 (2) 115.0 (16)
C4—H4⋯N5i 0.990 (18) 2.509 (19) 3.457 (2) 160.1 (14)
C7—H7⋯N3ii 0.988 (19) 2.58 (2) 3.444 (2) 146.2 (14)
C6—H6⋯Cg1iii 0.92 (2) 2.75 (2) 3.504 (2) 140.4 (16)
C11—H11⋯Cg2iv 1.00 (2) 2.86 (2) 3.602 (2) 131.9 (17)
Symmetry codes: (i) [x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]; (ii) [x+1, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]; (iii) [-x+1, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]; (iv) [-x, y+{\script{1\over 2}}, -z+{\script{3\over 2}}].

Data collection: SMART (Bruker, 2003[Bruker (2003). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2003[Bruker (2003). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEPII (Johnson, 1976[Johnson, C. K. (1976). ORTEPII. Report ORNL-5138. Oak Ridge National Laboratory, Tennessee, USA.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

1,2,4-triazoles and its derivatives have proven to be good multi-N-donor ligands (Haasnoot, 2000) coordinating first row transition metals in mononuclear complexes or bridging the metal atoms into polymeric complexes. Some of those complexes display interesting magnetic properties, for example, chains of Fe(II)-4-amino-1,2,4-triazole exhibit hysteretic spin transitions at around 200 K and dinuclear copper-4-amino-3,5bis(pyridin-2-yl) -1,2,4-triazole clusters order antiferromagnetically above 50 K (Dirtu et al., 2007; Koningsbruggen et al., 1995). Within a project of synthesizing new metal-triazole complexes, we have obtained crystals of the title compound. The 4-Amino-3,5-bis(pyridin-2-yl)-1,2,4-triazole molecules, I, Fig. 1, deviate slightly from planarity, as seen by the torsion angles N3—C2—C8—C9 - 2.7 (3) and C4—C3—C1—N2 4.6 (2)°. The molecule has a pseudo-twofold axis bisecting the triazole ring. Both H atoms of the amino group participate in intramolecular H-bonds with the pyridyl N atoms as acceptors, defining the molecule conformation (Table 1). In metal complexes, the pyridyl rings often rotate around the single C—C bond so that the pyridyl N atom can coordinate the metal ion, for instance like in 4-amino-3,5-bis(pyridin-2-yl)-1,2,4-triazole diaqua manganese dibromide (Faulmann et al. 1990).

C—H···π intermolecular interactions also occur between these organic molecules. One pyridyl carbon at each side of the molecule directs its H atom towards the electron cloud of neighbouring pyridyl aromatic rings linking the molecules together (Fig. 2). The geometry of the interaction corresponds to the type III as classified by Malone et al. (1997), with the H atoms positioned almost above the centroid of the acceptor ring and the C—H bond pointing towards the edge of the ring [C6···Cg1i 3.504 (2) ° and C6—H6···Cg1i angle 140.4 (16)°, i:1 - x,-1/2 + y,3/2 - z and Cg1 is the centroid of the six-membered ring N6—C8—C9—C10—C11—C12]. There is a similar interaction on the other end of the molecule (C11) but with a longer distance [3.602 (2) Å].

Related literature top

For related literature, see: Dirtu et al. (2007); Faulmann et al. (1990); Haasnoot (2000); van Koningsbruggen et al. (1995); Malone et al. (1997), Mernari et al. (1998).

Experimental top

0.02 mmol (0.005 g) of 4-amino-3,5-bis(pyridin-2-yl)-1,2,4-triazole were dissolved in 5 ml of dimethylformamide. 0.006 mmol (0.003 g) of NH4Fe(SO4)2.12H2O were then added to the solution.

Refinement top

The H atoms were located in Fourier difference maps and their coordinates were freely refined. Isotropic displacement factors were used for all H atoms with Uiso(H)=1.2Ueq(parent atom).

Computing details top

Data collection: SMART (Bruker, 2003); cell refinement: SAINT (Bruker, 2003); data reduction: SAINT (Bruker, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. ORTEPII (Johnson, 1976) plot of the title compound. Displacement ellipsoids are drawn at the 50% level.
[Figure 2] Fig. 2. Packing diagram of the title compound, showing the N—H···N intramolecular hydrogen bonds and the C—H···π intermolecular interactions as dashed lines. The green dot represents the centroid of the N6—C8—C9—C10—C11—C12 ring.
4-Amino-3,5-di-2-pyridyl-4H-1,2,4-triazole top
Crystal data top
C12H10N6F(000) = 496
Mr = 238.26Dx = 1.423 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3853 reflections
a = 6.6191 (2) Åθ = 2.3–22.9°
b = 14.7136 (4) ŵ = 0.09 mm1
c = 11.4703 (4) ÅT = 293 K
β = 95.474 (2)°Block, colourless
V = 1112.01 (6) Å30.20 × 0.13 × 0.12 mm
Z = 4
Data collection top
Bruker APEX CCD area-detector
diffractometer
2751 independent reflections
Radiation source: fine-focus sealed tube1465 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.052
ϕ and ω scansθmax = 28.4°, θmin = 2.3°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2000)
h = 88
Tmin = 0.91, Tmax = 0.99k = 1919
23253 measured reflectionsl = 1514
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)] = 0.045Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.116Only H-atom coordinates refined
S = 1.00 w = 1/[σ2(Fo2) + (0.046P)2 + 0.1952P]
where P = (Fo2 + 2Fc2)/3
2751 reflections(Δ/σ)max < 0.001
193 parametersΔρmax = 0.19 e Å3
0 restraintsΔρmin = 0.15 e Å3
Crystal data top
C12H10N6V = 1112.01 (6) Å3
Mr = 238.26Z = 4
Monoclinic, P21/cMo Kα radiation
a = 6.6191 (2) ŵ = 0.09 mm1
b = 14.7136 (4) ÅT = 293 K
c = 11.4703 (4) Å0.20 × 0.13 × 0.12 mm
β = 95.474 (2)°
Data collection top
Bruker APEX CCD area-detector
diffractometer
2751 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2000)
1465 reflections with I > 2σ(I)
Tmin = 0.91, Tmax = 0.99Rint = 0.052
23253 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0450 restraints
wR(F2) = 0.116Only H-atom coordinates refined
S = 1.00Δρmax = 0.19 e Å3
2751 reflectionsΔρmin = 0.15 e Å3
193 parameters
Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C20.1009 (3)0.37992 (12)0.68150 (16)0.0427 (4)
C70.7970 (3)0.18467 (13)0.82952 (18)0.0530 (5)
H70.836 (3)0.1715 (13)0.9131 (17)0.064*
N10.2528 (2)0.33629 (9)0.74750 (12)0.0384 (4)
C30.5629 (2)0.24896 (11)0.69618 (15)0.0379 (4)
N50.6192 (2)0.22823 (10)0.80804 (12)0.0465 (4)
N20.2987 (2)0.32021 (11)0.56204 (13)0.0501 (4)
N40.2880 (3)0.33726 (12)0.87071 (14)0.0519 (4)
H4A0.165 (3)0.3529 (14)0.8928 (16)0.062*
H4B0.330 (3)0.2842 (14)0.8950 (17)0.062*
C10.3737 (3)0.30049 (11)0.66995 (14)0.0391 (4)
C80.0739 (3)0.42729 (11)0.72304 (17)0.0449 (4)
N30.1269 (2)0.37060 (11)0.56956 (13)0.0519 (4)
C50.8555 (3)0.18073 (13)0.62990 (19)0.0531 (5)
H50.941 (3)0.1645 (13)0.5678 (17)0.064*
C60.9189 (3)0.16063 (13)0.74431 (19)0.0538 (5)
H61.043 (3)0.1340 (14)0.7618 (17)0.065*
C40.6753 (3)0.22542 (13)0.60482 (17)0.0480 (5)
H40.624 (3)0.2418 (13)0.5236 (16)0.058*
N60.0897 (3)0.42970 (12)0.83758 (16)0.0646 (5)
C110.3997 (3)0.51251 (15)0.7968 (3)0.0736 (7)
H110.519 (3)0.5398 (17)0.8311 (19)0.088*
C90.2150 (3)0.46755 (14)0.6418 (2)0.0603 (6)
H90.190 (3)0.4675 (14)0.5611 (19)0.072*
C100.3793 (3)0.51058 (15)0.6802 (3)0.0711 (7)
H100.482 (3)0.5412 (16)0.6283 (19)0.085*
C120.2542 (4)0.47175 (17)0.8721 (2)0.0802 (8)
H120.255 (3)0.4710 (16)0.960 (2)0.096*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C20.0435 (10)0.0367 (9)0.0468 (11)0.0022 (8)0.0023 (8)0.0011 (8)
C70.0573 (13)0.0494 (12)0.0509 (12)0.0076 (10)0.0027 (10)0.0060 (9)
N10.0419 (8)0.0365 (8)0.0364 (8)0.0017 (6)0.0019 (6)0.0009 (6)
C30.0403 (10)0.0328 (9)0.0402 (10)0.0060 (8)0.0014 (7)0.0004 (7)
N50.0500 (9)0.0468 (9)0.0420 (9)0.0050 (7)0.0010 (7)0.0029 (7)
N20.0528 (10)0.0531 (10)0.0428 (9)0.0067 (8)0.0035 (7)0.0006 (7)
N40.0557 (10)0.0604 (11)0.0400 (9)0.0125 (9)0.0061 (7)0.0026 (8)
C10.0420 (10)0.0379 (9)0.0372 (10)0.0047 (8)0.0025 (8)0.0004 (8)
C80.0425 (10)0.0312 (9)0.0610 (12)0.0031 (8)0.0044 (9)0.0017 (9)
N30.0539 (10)0.0505 (9)0.0491 (10)0.0070 (8)0.0060 (7)0.0004 (7)
C50.0515 (13)0.0498 (12)0.0601 (13)0.0011 (10)0.0172 (10)0.0055 (10)
C60.0455 (12)0.0408 (11)0.0749 (15)0.0046 (9)0.0041 (11)0.0014 (10)
C40.0479 (11)0.0531 (12)0.0435 (11)0.0027 (9)0.0076 (9)0.0003 (9)
N60.0655 (11)0.0583 (11)0.0734 (13)0.0183 (9)0.0243 (9)0.0182 (9)
C110.0536 (14)0.0501 (13)0.121 (2)0.0119 (11)0.0267 (14)0.0134 (14)
C90.0550 (13)0.0480 (12)0.0747 (15)0.0059 (10)0.0096 (11)0.0056 (11)
C100.0532 (14)0.0476 (13)0.109 (2)0.0097 (11)0.0094 (14)0.0053 (13)
C120.0793 (17)0.0738 (16)0.0932 (19)0.0264 (14)0.0378 (15)0.0253 (15)
Geometric parameters (Å, º) top
C2—N31.319 (2)C8—N61.328 (2)
C2—N11.361 (2)C8—C91.388 (3)
C2—C81.468 (2)C5—C41.369 (3)
C7—N51.342 (2)C5—C61.371 (3)
C7—C61.372 (3)C5—H50.979 (19)
C7—H70.988 (19)C6—H60.92 (2)
N1—C11.358 (2)C4—H40.990 (18)
N1—N41.410 (2)N6—C121.345 (3)
C3—N51.337 (2)C11—C101.358 (3)
C3—C41.386 (2)C11—C121.369 (3)
C3—C11.470 (2)C11—H111.00 (2)
N2—C11.321 (2)C9—C101.367 (3)
N2—N31.367 (2)C9—H90.96 (2)
N4—H4A0.91 (2)C10—H100.97 (2)
N4—H4B0.87 (2)C12—H121.01 (2)
N3—C2—N1109.53 (16)C2—N3—N2107.73 (14)
N3—C2—C8123.05 (16)C4—C5—C6119.04 (19)
N1—C2—C8127.35 (17)C4—C5—H5120.9 (12)
N5—C7—C6123.87 (19)C6—C5—H5120.0 (12)
N5—C7—H7114.5 (11)C5—C6—C7118.6 (2)
C6—C7—H7121.6 (11)C5—C6—H6119.2 (12)
C1—N1—C2105.60 (14)C7—C6—H6122.1 (12)
C1—N1—N4127.52 (15)C5—C4—C3118.76 (18)
C2—N1—N4126.53 (15)C5—C4—H4122.0 (10)
N5—C3—C4123.26 (17)C3—C4—H4119.3 (11)
N5—C3—C1117.90 (15)C8—N6—C12116.51 (19)
C4—C3—C1118.84 (16)C10—C11—C12118.8 (2)
C3—N5—C7116.38 (16)C10—C11—H11123.6 (13)
C1—N2—N3107.48 (14)C12—C11—H11117.5 (13)
N1—N4—H4A102.4 (12)C10—C9—C8119.1 (2)
N1—N4—H4B109.3 (13)C10—C9—H9122.1 (13)
H4A—N4—H4B114.2 (19)C8—C9—H9118.7 (13)
N2—C1—N1109.65 (15)C11—C10—C9119.0 (2)
N2—C1—C3122.78 (16)C11—C10—H10117.6 (13)
N1—C1—C3127.55 (15)C9—C10—H10123.4 (13)
N6—C8—C9122.78 (19)N6—C12—C11123.8 (2)
N6—C8—C2118.20 (16)N6—C12—H12111.7 (14)
C9—C8—C2119.03 (19)C11—C12—H12124.5 (14)
N3—C2—N1—C10.46 (18)N3—C2—C8—C92.7 (3)
C8—C2—N1—C1177.71 (16)N1—C2—C8—C9179.56 (17)
N3—C2—N1—N4174.11 (15)N1—C2—N3—N20.10 (19)
C8—C2—N1—N48.6 (3)C8—C2—N3—N2177.49 (15)
C4—C3—N5—C71.9 (3)C1—N2—N3—C20.32 (19)
C1—C3—N5—C7177.18 (15)C4—C5—C6—C71.2 (3)
C6—C7—N5—C30.5 (3)N5—C7—C6—C51.0 (3)
N3—N2—C1—N10.61 (19)C6—C5—C4—C30.1 (3)
N3—N2—C1—C3178.15 (15)N5—C3—C4—C51.7 (3)
C2—N1—C1—N20.67 (19)C1—C3—C4—C5177.34 (16)
N4—N1—C1—N2174.23 (16)C9—C8—N6—C121.6 (3)
C2—N1—C1—C3178.02 (16)C2—C8—N6—C12178.42 (18)
N4—N1—C1—C34.5 (3)N6—C8—C9—C100.9 (3)
N5—C3—C1—N2176.25 (16)C2—C8—C9—C10179.09 (18)
C4—C3—C1—N24.6 (2)C12—C11—C10—C90.4 (4)
N5—C3—C1—N15.2 (2)C8—C9—C10—C110.1 (3)
C4—C3—C1—N1173.88 (16)C8—N6—C12—C111.3 (4)
N3—C2—C8—N6177.36 (17)C10—C11—C12—N60.3 (4)
N1—C2—C8—N60.5 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N4—H4A···N60.91 (2)2.08 (2)2.839 (2)141.1 (17)
N4—H4B···N50.87 (2)2.39 (2)2.863 (2)115.0 (16)
C4—H4···N5i0.990 (18)2.509 (19)3.457 (2)160.1 (14)
C7—H7···N3ii0.988 (19)2.58 (2)3.444 (2)146.2 (14)
C6—H6···Cg1iii0.92 (2)2.75 (2)3.504 (2)140.4 (16)
C11—H11···Cg2iv1.00 (2)2.86 (2)3.602 (2)131.9 (17)
Symmetry codes: (i) x, y+1/2, z1/2; (ii) x+1, y+1/2, z+1/2; (iii) x+1, y1/2, z+3/2; (iv) x, y+1/2, z+3/2.

Experimental details

Crystal data
Chemical formulaC12H10N6
Mr238.26
Crystal system, space groupMonoclinic, P21/c
Temperature (K)293
a, b, c (Å)6.6191 (2), 14.7136 (4), 11.4703 (4)
β (°) 95.474 (2)
V3)1112.01 (6)
Z4
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.20 × 0.13 × 0.12
Data collection
DiffractometerBruker APEX CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2000)
Tmin, Tmax0.91, 0.99
No. of measured, independent and
observed [I > 2σ(I)] reflections
23253, 2751, 1465
Rint0.052
(sin θ/λ)max1)0.670
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.045, 0.116, 1.00
No. of reflections2751
No. of parameters193
H-atom treatmentOnly H-atom coordinates refined
Δρmax, Δρmin (e Å3)0.19, 0.15

Computer programs: SMART (Bruker, 2003), SAINT (Bruker, 2003), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEPII (Johnson, 1976).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N4—H4A···N60.91 (2)2.08 (2)2.839 (2)141.1 (17)
N4—H4B···N50.87 (2)2.39 (2)2.863 (2)115.0 (16)
C4—H4···N5i0.990 (18)2.509 (19)3.457 (2)160.1 (14)
C7—H7···N3ii0.988 (19)2.58 (2)3.444 (2)146.2 (14)
C6—H6···Cg1iii0.92 (2)2.75 (2)3.504 (2)140.4 (16)
C11—H11···Cg2iv1.00 (2)2.86 (2)3.602 (2)131.9 (17)
Symmetry codes: (i) x, y+1/2, z1/2; (ii) x+1, y+1/2, z+1/2; (iii) x+1, y1/2, z+3/2; (iv) x, y+1/2, z+3/2.
 

Acknowledgements

This work was supported by Fundação para a Ciência e a Tecnologia (FCT) under project POCI/FIS/57876/2004.

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