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Crystal structure of 1-(1-methyl-1H-imidazol-2-yl)-4-phenyl-1H-1,2,3-triazole dihydrate

aUniversity of Innsbruck, Faculty of Chemistry and Pharmacy, Innrain 80, 6020 Innsbruck, Austria
*Correspondence e-mail: gerhard.laus@uibk.ac.at

Edited by W. T. A. Harrison, University of Aberdeen, Scotland (Received 30 October 2015; accepted 1 November 2015; online 14 November 2015)

The title compound, C12H11N5·2H2O, which crystallizes as a dihydrate, was obtained by CuI-catalysed azide–alkyne cyclo­addition from 2-azido-1-methyl­imidazole and phenyl­ethyne. The dihedral angles between the central triazole ring (r.m.s. deviation = 0.004 Å) and the pendant imidazole (r.m.s. deviation = 0.006 Å) and phenyl rings are 12.3 (2) and 2.54 (19)°, respectively. In the crystal, the water mol­ecules are connected into [010] chains by O—H⋯O hydrogen bonds, while O—H⋯N hydrogen bonds connect the water mol­ecules to the organic mol­ecules, generating corrugated (100) sheets.

1. Related literature

For the synthesis and thermal cyclo­addition of 2-azido-1-methyl­imidazole, see: Zanirato & Cerini (2005[Zanirato, P. & Cerini, S. (2005). Org. Biomol. Chem. 3, 1508-1513.]). For related structures, see: Ramana & Punniyamurthy (2012[Ramana, T. & Punniyamurthy, T. (2012). Chem. Eur. J. 18, 13279-13283.]). For background to 1,2,3-triazoles as peptidomimetics, see: Angell & Burgess (2007[Angell, Y. L. & Burgess, K. (2007). Chem. Soc. Rev. 36, 1674-1689.]); Pedersen & Abell (2011[Pedersen, D. S. & Abell, A. (2011). Eur. J. Org. Chem. pp. 2399-2411.]); Tron et al. (2008[Tron, G. C., Pirali, T., Billington, R. A., Canonico, P. L., Sorba, G. & Genazzani, A. A. (2008). Med. Res. Rev. 28, 278-308.]). For copper(I)-catalysed azide–alkyne cyclo­additions, see: Haldón et al. (2015[Haldón, E., Nicasio, M. C. & Pérez, P. J. (2015). Org. Biomol. Chem. 13, 9528-9550.]); Meldal & Tornoe (2008[Meldal, M. & Tornøe, C. W. (2008). Chem. Rev. 108, 2952-3015.]); Rostovtsev et al. (2002[Rostovtsev, V. V., Green, L. G., Fokin, V. V. & Sharpless, K. B. (2002). Angew. Chem. Int. Ed. 41, 2596-2599.]).

[Scheme 1]

2. Experimental

2.1. Crystal data

  • C12H11N5·2H2O

  • Mr = 261.29

  • Orthorhombic, P n a 21

  • a = 18.8585 (9) Å

  • b = 4.7884 (2) Å

  • c = 14.4285 (6) Å

  • V = 1302.92 (10) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 233 K

  • 0.40 × 0.05 × 0.05 mm

2.2. Data collection

  • Nonius KappaCCD diffractometer

  • 6624 measured reflections

  • 2277 independent reflections

  • 1878 reflections with I > 2σ(I)

  • Rint = 0.050

2.3. Refinement

  • R[F2 > 2σ(F2)] = 0.045

  • wR(F2) = 0.088

  • S = 1.08

  • 2277 reflections

  • 190 parameters

  • 5 restraints

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

  • Δρmax = 0.15 e Å−3

  • Δρmin = −0.15 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1A⋯N2 0.85 (3) 2.02 (3) 2.863 (4) 172 (4)
O1—H1B⋯O2i 0.86 (3) 1.91 (4) 2.768 (4) 176 (4)
O2—H2A⋯N5ii 0.82 (4) 2.19 (4) 3.007 (4) 174 (4)
O2—H2B⋯O1 0.84 (4) 1.92 (4) 2.750 (4) 170 (4)
Symmetry codes: (i) x, y-1, z; (ii) [-x+1, -y+2, z-{\script{1\over 2}}].

Data collection: COLLECT (Hooft, 1998[Hooft, R. W. W. (1998). COLLECT. Nonius BV, Delft, The Netherlands.]); cell refinement: DENZO and SCALEPACK (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]); data reduction: DENZO and SCALEPACK; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015[Sheldrick, G. M. (2015). Acta Cryst. C71, 3-8.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and Mercury (Macrae et al., 2006[Macrae, C. F., Edgington, P. R., McCabe, P., Pidcock, E., Shields, G. P., Taylor, R., Towler, M. & van de Streek, J. (2006). J. Appl. Cryst. 39, 453-457.]); software used to prepare material for publication: SHELXL2014.

Supporting information


Comment top

Due to the structural and stereoelectronic similarity between 1,2,3-triazoles and amide bonds, this class of heterocycles holds promising potential as peptidomimetics (Angell & Burgess, 2007; Pedersen & Abell, 2011; Tron et al., 2008) with improved biological activities. The molecular structure of the title compound is shown in Figure 1. The interplanar angle between the imidazole and triazole rings is 12.3°, whereas the angle between the triazole and phenyl ring planes is only 2.5°. The two independent water molecules form infinite chains via O—H···O hydrogen bonds and donate O1—H···N2 and O2—H···N5 hydrogen bonds to the imidazole and triazole moieties (Figure 2). The hydrogen bond geometries are summarized in Table 1.

Related literature top

For the synthesis and thermal cycloaddition of 2-azido-1-methylimidazole, see: Zanirato & Cerini (2005). For related structures, see: Ramana & Punniyamurthy (2012). For background to 1,2,3-triazoles as peptidomimetics, see: Angell & Burgess (2007); Pedersen & Abell (2011); Tron et al. (2008). For copper(I)-catalysed azide–alkyne cycloadditions, see: Haldón et al. (2015); Meldal & Tornoe (2008); Rostovtsev et al. (2002).

Experimental top

The thermal cycloaddition of azidoazoles with (trimethylsilyl)ethyne has been reported to require extraordinarily long reaction times and chromatographic separation of the resulting isomers (Zanirato & Cerini, 2005). On the other hand, copper(I)-catalysed azide-alkyne cycloadditions (Haldón et al., 2015; Meldal & Tornoe, 2008; Rostovtsev et al., 2002) exhibit more favorable rates and excellent selectivities. The 2-azido-1-methylimidazole was prepared by lithiation and azidation of 1-methylimidazole followed by fragmentation of the resulting tosyltriazenyl salt according to the literature (Zanirato & Cerini, 2005). Thus, the aqueous solution (20 ml) of 2-azido-1-methylimidazole (1.1 mmol) was deoxygenated in a stream of argon. Phenylethyne (0.14 ml, 1.2 mmol), CuSO4.5H2O (27 mg, 0.1 mmol) and sodium ascorbate (64 mg, 0.3 mmol) were subsequently added. This suspension was stirred at room temperature for 20 h. The white precipitate was collected by filtration and recrystallized from a mixture of acetone (10 ml) and H2O (0.5 ml) to yield colorless needles (47 mg, 20%). Melting point: 77 °C. IR (neat): ν 1546, 1514, 1478, 1278, 1024, 1005, 762, 689 cm-1. 1H NMR (DMSO-d6, 300 MHz): δ 3.72(s, 3H), 7.06 (s, 1H), 7.39 (t, 1H; J = 7.6 Hz), 7.42 (s, 1H), 7.50 (t, 2H; J = 7.6 Hz), 7.99 (d, 2H; J = 7.6 Hz), 9.13 (s, 1H) p.p.m. 13C NMR (DMSO-d6, 75 MHz): δ 33.5, 122.8, 123.3, 125.5 (2 C), 126.3, 128.5, 129.0 (2 C), 129.8, 136.9, 146.4 p.p.m.

Refinement top

Carbon-bound H atoms were placed in calculated positions and refined riding on their respective carbon atom. Methyl H atoms were fitted to the experimental electron density by allowing them to rotate around the C—C bond with a fixed angle (HFIX 137). Isotropic displacement parameters were constrained with Uiso(H) = 1.5Ueq(C) for methyl H atoms and 1.2Ueq(C) for other H atoms. The H atoms of the water molecules were located from a Fourier map and restrained with a distance of O—H = 0.83 (2) Å.

Structure description top

Due to the structural and stereoelectronic similarity between 1,2,3-triazoles and amide bonds, this class of heterocycles holds promising potential as peptidomimetics (Angell & Burgess, 2007; Pedersen & Abell, 2011; Tron et al., 2008) with improved biological activities. The molecular structure of the title compound is shown in Figure 1. The interplanar angle between the imidazole and triazole rings is 12.3°, whereas the angle between the triazole and phenyl ring planes is only 2.5°. The two independent water molecules form infinite chains via O—H···O hydrogen bonds and donate O1—H···N2 and O2—H···N5 hydrogen bonds to the imidazole and triazole moieties (Figure 2). The hydrogen bond geometries are summarized in Table 1.

For the synthesis and thermal cycloaddition of 2-azido-1-methylimidazole, see: Zanirato & Cerini (2005). For related structures, see: Ramana & Punniyamurthy (2012). For background to 1,2,3-triazoles as peptidomimetics, see: Angell & Burgess (2007); Pedersen & Abell (2011); Tron et al. (2008). For copper(I)-catalysed azide–alkyne cycloadditions, see: Haldón et al. (2015); Meldal & Tornoe (2008); Rostovtsev et al. (2002).

Computing details top

Data collection: COLLECT (Hooft, 1998); cell refinement: DENZO and SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO and SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXL2014 (Sheldrick, 2015).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, with atom labels and 50% probability displacement ellipsoids for non-H atoms. The water molecules are not shown.
[Figure 2] Fig. 2. Infinite chains of hydrogen-bonded water molecules link the heterocyclic molecules.
1-(1-Methyl-1H-imidazol-2-yl)-4-phenyl-1H-1,2,3-triazole dihydrate top
Crystal data top
C12H11N5·2H2ODx = 1.332 Mg m3
Mr = 261.29Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Pna21Cell parameters from 18840 reflections
a = 18.8585 (9) Åθ = 1.0–25.2°
b = 4.7884 (2) ŵ = 0.10 mm1
c = 14.4285 (6) ÅT = 233 K
V = 1302.92 (10) Å3Prism, colourless
Z = 40.40 × 0.05 × 0.05 mm
F(000) = 552
Data collection top
Nonius KappaCCD
diffractometer
Rint = 0.050
Detector resolution: 9.4 pixels mm-1θmax = 25.0°, θmin = 2.2°
phi– and ω–scansh = 1822
6624 measured reflectionsk = 55
2277 independent reflectionsl = 1717
1878 reflections with I > 2σ(I)
Refinement top
Refinement on F2Hydrogen site location: mixed
Least-squares matrix: fullH atoms treated by a mixture of independent and constrained refinement
R[F2 > 2σ(F2)] = 0.045 w = 1/[σ2(Fo2) + (0.0315P)2 + 0.2291P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.088(Δ/σ)max < 0.001
S = 1.08Δρmax = 0.15 e Å3
2277 reflectionsΔρmin = 0.15 e Å3
190 parametersExtinction correction: SHELXL2014 (Sheldrick 2015), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
5 restraintsExtinction coefficient: 0.018 (3)
Crystal data top
C12H11N5·2H2OV = 1302.92 (10) Å3
Mr = 261.29Z = 4
Orthorhombic, Pna21Mo Kα radiation
a = 18.8585 (9) ŵ = 0.10 mm1
b = 4.7884 (2) ÅT = 233 K
c = 14.4285 (6) Å0.40 × 0.05 × 0.05 mm
Data collection top
Nonius KappaCCD
diffractometer
1878 reflections with I > 2σ(I)
6624 measured reflectionsRint = 0.050
2277 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0455 restraints
wR(F2) = 0.088H atoms treated by a mixture of independent and constrained refinement
S = 1.08Δρmax = 0.15 e Å3
2277 reflectionsΔρmin = 0.15 e Å3
190 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. Hydrogen atoms at water molecules were found and refined isotropically with a bond restraint, d = 0.83 (2) Å.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
N10.71035 (16)0.4793 (6)1.0472 (2)0.0432 (7)
N20.69605 (16)0.5200 (6)0.89493 (19)0.0439 (7)
N30.62108 (14)0.8035 (6)0.98838 (18)0.0384 (7)
N40.58989 (17)0.8522 (7)1.0712 (2)0.0504 (8)
N50.54108 (16)1.0443 (6)1.0565 (2)0.0491 (8)
C10.67522 (16)0.6024 (7)0.9768 (3)0.0387 (8)
C20.75758 (19)0.2996 (8)1.0060 (3)0.0484 (9)
H20.79000.18151.03610.058*
C30.74817 (19)0.3260 (7)0.9139 (3)0.0487 (9)
H30.77360.22600.86870.058*
C40.7052 (2)0.5242 (10)1.1475 (3)0.0698 (13)
H4A0.65850.46851.16880.105*
H4B0.71270.72031.16120.105*
H4C0.74090.41331.17880.105*
C50.59235 (19)0.9645 (7)0.9213 (3)0.0404 (9)
H50.60470.96940.85820.048*
C60.54150 (17)1.1183 (7)0.9651 (2)0.0368 (8)
C70.49322 (18)1.3296 (7)0.9261 (2)0.0387 (8)
C80.49478 (18)1.3869 (8)0.8321 (2)0.0446 (9)
H80.52631.28920.79350.054*
C90.4501 (2)1.5875 (8)0.7944 (3)0.0523 (10)
H90.45161.62600.73060.063*
C100.4035 (2)1.7299 (8)0.8506 (3)0.0525 (10)
H100.37321.86510.82500.063*
C110.4012 (2)1.6750 (8)0.9445 (3)0.0492 (10)
H110.36901.77160.98260.059*
C120.44632 (18)1.4772 (6)0.9824 (3)0.0442 (9)
H120.44531.44231.04650.053*
O10.66022 (15)0.5304 (6)0.70215 (18)0.0527 (8)
O20.59225 (17)1.0282 (6)0.6683 (2)0.0566 (8)
H1A0.675 (3)0.533 (11)0.758 (2)0.12 (2)*
H1B0.641 (2)0.371 (7)0.692 (3)0.079 (15)*
H2A0.5546 (17)1.019 (9)0.640 (3)0.077 (16)*
H2B0.608 (2)0.869 (7)0.680 (4)0.081 (16)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0357 (16)0.0487 (17)0.0453 (18)0.0013 (15)0.0035 (14)0.0036 (14)
N20.0433 (17)0.0464 (17)0.0419 (18)0.0012 (14)0.0035 (15)0.0052 (13)
N30.0364 (15)0.0410 (16)0.0377 (16)0.0046 (13)0.0002 (15)0.0002 (14)
N40.0510 (18)0.0620 (19)0.0384 (17)0.0082 (17)0.0022 (15)0.0006 (15)
N50.0471 (18)0.057 (2)0.0431 (17)0.0070 (16)0.0016 (15)0.0006 (15)
C10.0302 (17)0.0374 (18)0.048 (2)0.0061 (15)0.0008 (16)0.0014 (17)
C20.0373 (19)0.047 (2)0.061 (2)0.0046 (18)0.0009 (19)0.0036 (19)
C30.040 (2)0.045 (2)0.061 (3)0.0021 (17)0.0027 (19)0.005 (2)
C40.059 (3)0.105 (4)0.045 (3)0.014 (3)0.003 (2)0.006 (2)
C50.042 (2)0.0401 (19)0.0391 (19)0.0072 (17)0.0023 (17)0.0005 (17)
C60.0364 (18)0.0347 (18)0.0394 (18)0.0070 (15)0.0018 (16)0.0004 (16)
C70.0355 (19)0.0357 (19)0.0449 (19)0.0075 (16)0.0023 (16)0.0023 (17)
C80.040 (2)0.048 (2)0.045 (2)0.0015 (18)0.0019 (18)0.0053 (17)
C90.050 (2)0.062 (3)0.044 (2)0.005 (2)0.0038 (19)0.006 (2)
C100.049 (2)0.045 (2)0.064 (3)0.0005 (19)0.008 (2)0.004 (2)
C110.048 (2)0.041 (2)0.059 (3)0.0023 (19)0.0046 (17)0.0021 (17)
C120.050 (2)0.040 (2)0.043 (2)0.0013 (17)0.0071 (18)0.0018 (17)
O10.0603 (19)0.0462 (17)0.0514 (19)0.0029 (14)0.0028 (14)0.0066 (13)
O20.062 (2)0.0472 (17)0.0608 (18)0.0040 (15)0.0141 (16)0.0078 (14)
Geometric parameters (Å, º) top
N1—C11.347 (5)C5—H50.9400
N1—C21.374 (4)C6—C71.472 (5)
N1—C41.467 (5)C7—C81.385 (5)
N2—C11.306 (5)C7—C121.393 (5)
N2—C31.380 (5)C8—C91.389 (5)
N3—C51.350 (4)C8—H80.9400
N3—N41.352 (4)C9—C101.376 (5)
N3—C11.413 (4)C9—H90.9400
N4—N51.318 (4)C10—C111.380 (5)
N5—C61.366 (5)C10—H100.9400
C2—C31.347 (5)C11—C121.386 (5)
C2—H20.9400C11—H110.9400
C3—H30.9400C12—H120.9400
C4—H4A0.9700O1—H1A0.85 (3)
C4—H4B0.9700O1—H1B0.86 (3)
C4—H4C0.9700O2—H2A0.82 (3)
C5—C61.364 (5)O2—H2B0.84 (3)
C1—N1—C2105.5 (3)N3—C5—H5127.5
C1—N1—C4130.3 (3)C6—C5—H5127.5
C2—N1—C4124.2 (3)C5—C6—N5108.1 (3)
C1—N2—C3103.8 (3)C5—C6—C7129.0 (3)
C5—N3—N4111.1 (3)N5—C6—C7122.9 (3)
C5—N3—C1126.5 (3)C8—C7—C12118.9 (3)
N4—N3—C1122.4 (3)C8—C7—C6119.8 (3)
N5—N4—N3106.4 (3)C12—C7—C6121.3 (3)
N4—N5—C6109.4 (3)C7—C8—C9120.5 (3)
N2—C1—N1113.7 (3)C7—C8—H8119.7
N2—C1—N3122.0 (3)C9—C8—H8119.7
N1—C1—N3124.4 (3)C10—C9—C8120.0 (4)
C3—C2—N1106.4 (3)C10—C9—H9120.0
C3—C2—H2126.8C8—C9—H9120.0
N1—C2—H2126.8C9—C10—C11120.3 (4)
C2—C3—N2110.6 (3)C9—C10—H10119.9
C2—C3—H3124.7C11—C10—H10119.9
N2—C3—H3124.7C10—C11—C12119.8 (4)
N1—C4—H4A109.5C10—C11—H11120.1
N1—C4—H4B109.5C12—C11—H11120.1
H4A—C4—H4B109.5C11—C12—C7120.5 (3)
N1—C4—H4C109.5C11—C12—H12119.8
H4A—C4—H4C109.5C7—C12—H12119.8
H4B—C4—H4C109.5H1A—O1—H1B108 (5)
N3—C5—C6105.0 (3)H2A—O2—H2B111 (5)
C5—N3—N4—N50.2 (4)C1—N3—C5—C6178.4 (3)
C1—N3—N4—N5178.3 (3)N3—C5—C6—N50.3 (4)
N3—N4—N5—C60.4 (4)N3—C5—C6—C7180.0 (3)
C3—N2—C1—N10.8 (4)N4—N5—C6—C50.4 (4)
C3—N2—C1—N3179.6 (3)N4—N5—C6—C7179.8 (3)
C2—N1—C1—N20.6 (4)C5—C6—C7—C82.1 (5)
C4—N1—C1—N2176.7 (4)N5—C6—C7—C8177.6 (3)
C2—N1—C1—N3179.8 (3)C5—C6—C7—C12177.0 (3)
C4—N1—C1—N32.9 (6)N5—C6—C7—C123.3 (5)
C5—N3—C1—N210.9 (5)C12—C7—C8—C90.2 (5)
N4—N3—C1—N2167.3 (3)C6—C7—C8—C9179.4 (3)
C5—N3—C1—N1168.6 (3)C7—C8—C9—C100.4 (5)
N4—N3—C1—N113.2 (5)C8—C9—C10—C110.2 (6)
C1—N1—C2—C30.2 (4)C9—C10—C11—C120.5 (6)
C4—N1—C2—C3177.4 (4)C10—C11—C12—C71.1 (5)
N1—C2—C3—N20.3 (4)C8—C7—C12—C111.0 (5)
C1—N2—C3—C20.6 (4)C6—C7—C12—C11179.9 (3)
N4—N3—C5—C60.1 (4)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1A···N20.85 (3)2.02 (3)2.863 (4)172 (4)
O1—H1B···O2i0.86 (3)1.91 (4)2.768 (4)176 (4)
O2—H2A···N5ii0.82 (4)2.19 (4)3.007 (4)174 (4)
O2—H2B···O10.84 (4)1.92 (4)2.750 (4)170 (4)
Symmetry codes: (i) x, y1, z; (ii) x+1, y+2, z1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1A···N20.85 (3)2.02 (3)2.863 (4)172 (4)
O1—H1B···O2i0.86 (3)1.91 (4)2.768 (4)176 (4)
O2—H2A···N5ii0.82 (4)2.19 (4)3.007 (4)174 (4)
O2—H2B···O10.84 (4)1.92 (4)2.750 (4)170 (4)
Symmetry codes: (i) x, y1, z; (ii) x+1, y+2, z1/2.
 

References

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