organic compounds
Ethylenediammonium bis(5-methyl-3-oxo-2-phenyl-2,3-dihydropyrazol-1-ide): a hydrogen-bond-supported supramolecular ionic assembly
aMaterials Chemistry Laboratory, Nanjing University of Science and Technology, Nanjing 210094, People's Republic of China, bDepartment of Chemical Engineering, Huaihai Institute of Technology, Lianyungang 222005, People's Republic of China, and cCollege of Chemistry and Chemical Engineering, Liaocheng University, Shandong 252059, People's Republic of China
*Correspondence e-mail: xuruibo9125@163.com
The title compound, C2H10N22+·2C10H9N2O−, is composed of deprotonated 5-methyl-2-phenyl-1H-pyrazol-3(2H)-one anions (PMP−) and protonated ethylenediamine cations (H2en2+). The ethylenediammonium ion is located on a crystallographic inversion center. The dihedral angle between the phenyl and pyrazole rings is 39.73 (8)°. The two components are connected through N—H⋯O and N—H⋯N hydrogen bonds, forming an infinite three-dimensional network.
Related literature
For related literature on pyrazolones, see: Cerchiaro et al. (2006). For conductivity data for ionic electrolytes, see: Kwak et al. (2004); Allmann et al. (1990). For background information on hydrogen bonds and their importance and applications, see: Fu et al. (2004); Hernández-Galindo et al. (2007); Hu et al. (2004); Li & Wang (2007); Peng et al. (2005); Yang et al. (2002, 2005, 2006); Zhou et al. (2006).
Experimental
Crystal data
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Data collection
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Refinement
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Data collection: SMART (Siemens, 1996); cell SAINT (Siemens, 1996); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.
Supporting information
10.1107/S1600536808026378/zl2127sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536808026378/zl2127Isup2.hkl
A solution of PMP (2 mmol in 10 ml anhydrous methanol) was added dropwise with constant stirring to the solution of en (2 mmol in 10 ml anhydrous methanol) at 323 K for 2 h. The resulting mixture was filtrated. After cooling, the filtrate was evaporated at ambient environment. Several days later, pink blocky crystals suitable for X-ray analysis were collected and washed with a small amount of methanol and dried at room temperature (yield 67%. m.p. 438–441 K). Anal. Calcd (%) for C22H28N6O2 (Mr = 408.5): C, 64.69; H, 6.91; N, 20.57. Found (%): C, 64.73; H, 6.97; N, 20.52. UV-vis (methanol): λ max = 239 nm, ε = 2.655. The molar conductance of the compound in anhydrous methanol was 45.1 Ω -1cm2mol-1, much lower than that expected for a 1:2 electrolyte, indicating that the compound is forming ion pairs and larger assemblies tightly bonded to each other by e.g. hydrogen bonds (Allmann et al., 1990; Kwak et al., 2004).
H atoms were placed in calculated positions with C—H = 0.92Å (pyrazolyl), 0.93 Å (phenyl), 0.96 Å (methyl), 0.97 Å (methylene) and N—H = 0.89 Å (amino), and were refined in riding mode with Uiso(H) = 1.5 Ueq(C) (methyl) and Uiso(H) = 1.2 Ueq(C, N) (pyrazolyl, phenyl, methylene and amino).
Data collection: SMART (Siemens, 1996); cell
SAINT (Siemens, 1996); data reduction: SAINT (Siemens, 1996); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).C2H10N22+·2(C10H9N2O−) | Melting point = 441–438 K |
Mr = 408.50 | Mo Kα radiation, λ = 0.71073 Å |
Tetragonal, P42/n | Cell parameters from 2381 reflections |
a = 17.179 (2) Å | θ = 3.1–24.1° |
c = 7.0929 (15) Å | µ = 0.09 mm−1 |
V = 2093.2 (6) Å3 | T = 298 K |
Z = 4 | Block, pink |
F(000) = 872 | 0.24 × 0.22 × 0.17 mm |
Dx = 1.296 Mg m−3 |
Siemens SMART CCD area-detector diffractometer | 1284 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.046 |
Graphite monochromator | θmax = 25.0°, θmin = 1.7° |
ϕ and ω scans | h = −18→20 |
10541 measured reflections | k = −15→20 |
1856 independent reflections | l = −8→8 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.043 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.141 | H-atom parameters constrained |
S = 1.04 | w = 1/[σ2(Fo2) + (0.0642P)2 + 1.1449P] where P = (Fo2 + 2Fc2)/3 |
1856 reflections | (Δ/σ)max < 0.001 |
136 parameters | Δρmax = 0.22 e Å−3 |
0 restraints | Δρmin = −0.16 e Å−3 |
C2H10N22+·2(C10H9N2O−) | Z = 4 |
Mr = 408.50 | Mo Kα radiation |
Tetragonal, P42/n | µ = 0.09 mm−1 |
a = 17.179 (2) Å | T = 298 K |
c = 7.0929 (15) Å | 0.24 × 0.22 × 0.17 mm |
V = 2093.2 (6) Å3 |
Siemens SMART CCD area-detector diffractometer | 1284 reflections with I > 2σ(I) |
10541 measured reflections | Rint = 0.046 |
1856 independent reflections |
R[F2 > 2σ(F2)] = 0.043 | 0 restraints |
wR(F2) = 0.141 | H-atom parameters constrained |
S = 1.04 | Δρmax = 0.22 e Å−3 |
1856 reflections | Δρmin = −0.16 e Å−3 |
136 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 | 0.50902 (11) | 0.26458 (10) | 0.1311 (3) | 0.0316 (5) | |
N2 | 0.55431 (11) | 0.19843 (11) | 0.0995 (3) | 0.0363 (5) | |
N3 | 0.45643 (11) | 0.51464 (11) | 0.2591 (3) | 0.0329 (5) | |
H3A | 0.4611 | 0.4662 | 0.2161 | 0.049* | |
H3B | 0.4679 | 0.5481 | 0.1675 | 0.049* | |
H3C | 0.4078 | 0.5226 | 0.2977 | 0.049* | |
O1 | 0.50279 (10) | 0.39457 (9) | 0.0303 (2) | 0.0428 (5) | |
C1 | 0.53354 (13) | 0.32631 (13) | 0.0203 (3) | 0.0320 (5) | |
C2 | 0.59414 (14) | 0.29704 (13) | −0.0881 (3) | 0.0354 (6) | |
H2 | 0.6225 | 0.3239 | −0.1788 | 0.042* | |
C3 | 0.60418 (14) | 0.21958 (13) | −0.0345 (3) | 0.0364 (6) | |
C4 | 0.66173 (18) | 0.16275 (17) | −0.1105 (4) | 0.0579 (8) | |
H4A | 0.6533 | 0.1128 | −0.0533 | 0.087* | |
H4B | 0.7135 | 0.1804 | −0.0825 | 0.087* | |
H4C | 0.6554 | 0.1585 | −0.2446 | 0.087* | |
C5 | 0.46305 (12) | 0.26868 (12) | 0.2962 (3) | 0.0298 (5) | |
C6 | 0.39474 (13) | 0.31290 (14) | 0.2980 (3) | 0.0373 (6) | |
H6 | 0.3778 | 0.3380 | 0.1893 | 0.045* | |
C7 | 0.35267 (15) | 0.31879 (15) | 0.4635 (4) | 0.0444 (7) | |
H7 | 0.3077 | 0.3489 | 0.4661 | 0.053* | |
C8 | 0.37619 (15) | 0.28079 (15) | 0.6244 (4) | 0.0451 (7) | |
H8 | 0.3476 | 0.2857 | 0.7351 | 0.054* | |
C9 | 0.44250 (15) | 0.23530 (14) | 0.6208 (4) | 0.0414 (6) | |
H9 | 0.4578 | 0.2085 | 0.7285 | 0.050* | |
C10 | 0.48621 (13) | 0.22946 (13) | 0.4580 (3) | 0.0349 (6) | |
H10 | 0.5311 | 0.1993 | 0.4567 | 0.042* | |
C11 | 0.51023 (13) | 0.52621 (14) | 0.4182 (3) | 0.0349 (6) | |
H11A | 0.5080 | 0.5801 | 0.4588 | 0.042* | |
H11B | 0.5630 | 0.5153 | 0.3773 | 0.042* |
U11 | U22 | U33 | U12 | U13 | U23 | |
N1 | 0.0388 (11) | 0.0248 (10) | 0.0314 (10) | 0.0026 (8) | 0.0055 (9) | 0.0014 (8) |
N2 | 0.0446 (12) | 0.0273 (10) | 0.0370 (11) | 0.0061 (9) | 0.0070 (9) | 0.0007 (8) |
N3 | 0.0364 (11) | 0.0309 (10) | 0.0313 (10) | 0.0010 (8) | 0.0033 (8) | 0.0021 (8) |
O1 | 0.0609 (11) | 0.0284 (9) | 0.0391 (10) | 0.0102 (8) | 0.0137 (8) | 0.0063 (7) |
C1 | 0.0414 (13) | 0.0280 (12) | 0.0266 (11) | −0.0013 (10) | −0.0001 (10) | 0.0003 (9) |
C2 | 0.0432 (14) | 0.0328 (13) | 0.0300 (12) | 0.0004 (11) | 0.0083 (10) | 0.0022 (10) |
C3 | 0.0410 (14) | 0.0358 (13) | 0.0324 (13) | 0.0055 (11) | 0.0017 (11) | −0.0037 (10) |
C4 | 0.070 (2) | 0.0500 (17) | 0.0532 (17) | 0.0183 (15) | 0.0204 (15) | 0.0015 (14) |
C5 | 0.0292 (12) | 0.0264 (12) | 0.0338 (12) | −0.0034 (9) | 0.0014 (10) | 0.0002 (9) |
C6 | 0.0349 (13) | 0.0371 (13) | 0.0398 (14) | 0.0024 (11) | −0.0013 (11) | 0.0043 (11) |
C7 | 0.0378 (14) | 0.0427 (15) | 0.0526 (16) | 0.0072 (11) | 0.0107 (12) | 0.0049 (13) |
C8 | 0.0450 (15) | 0.0485 (16) | 0.0417 (15) | −0.0008 (12) | 0.0152 (12) | 0.0036 (12) |
C9 | 0.0452 (15) | 0.0442 (15) | 0.0349 (14) | −0.0008 (12) | 0.0026 (11) | 0.0083 (11) |
C10 | 0.0334 (13) | 0.0324 (13) | 0.0388 (14) | 0.0009 (10) | −0.0004 (11) | 0.0020 (10) |
C11 | 0.0321 (12) | 0.0387 (14) | 0.0340 (13) | −0.0020 (10) | −0.0003 (10) | 0.0026 (10) |
N1—C1 | 1.385 (3) | C4—H4C | 0.9600 |
N1—N2 | 1.395 (2) | C5—C10 | 1.388 (3) |
N1—C5 | 1.414 (3) | C5—C6 | 1.398 (3) |
N2—C3 | 1.330 (3) | C6—C7 | 1.382 (3) |
N3—C11 | 1.472 (3) | C6—H6 | 0.9300 |
N3—H3A | 0.8900 | C7—C8 | 1.375 (4) |
N3—H3B | 0.8900 | C7—H7 | 0.9300 |
N3—H3C | 0.8900 | C8—C9 | 1.382 (4) |
O1—C1 | 1.288 (3) | C8—H8 | 0.9300 |
C1—C2 | 1.389 (3) | C9—C10 | 1.381 (3) |
C2—C3 | 1.394 (3) | C9—H9 | 0.9300 |
C2—H2 | 0.9300 | C10—H10 | 0.9300 |
C3—C4 | 1.490 (3) | C11—C11i | 1.510 (4) |
C4—H4A | 0.9600 | C11—H11A | 0.9700 |
C4—H4B | 0.9600 | C11—H11B | 0.9700 |
C1—N1—N2 | 111.27 (17) | C10—C5—C6 | 119.8 (2) |
C1—N1—C5 | 126.97 (18) | C10—C5—N1 | 120.0 (2) |
N2—N1—C5 | 119.01 (17) | C6—C5—N1 | 120.2 (2) |
C3—N2—N1 | 104.56 (18) | C7—C6—C5 | 119.1 (2) |
C11—N3—H3A | 109.5 | C7—C6—H6 | 120.5 |
C11—N3—H3B | 109.5 | C5—C6—H6 | 120.5 |
H3A—N3—H3B | 109.5 | C8—C7—C6 | 121.1 (2) |
C11—N3—H3C | 109.5 | C8—C7—H7 | 119.5 |
H3A—N3—H3C | 109.5 | C6—C7—H7 | 119.5 |
H3B—N3—H3C | 109.5 | C7—C8—C9 | 119.7 (2) |
O1—C1—N1 | 122.8 (2) | C7—C8—H8 | 120.2 |
O1—C1—C2 | 131.9 (2) | C9—C8—H8 | 120.2 |
N1—C1—C2 | 105.35 (19) | C10—C9—C8 | 120.3 (2) |
C1—C2—C3 | 106.7 (2) | C10—C9—H9 | 119.8 |
C1—C2—H2 | 126.6 | C8—C9—H9 | 119.8 |
C3—C2—H2 | 126.6 | C9—C10—C5 | 120.0 (2) |
N2—C3—C2 | 112.1 (2) | C9—C10—H10 | 120.0 |
N2—C3—C4 | 120.4 (2) | C5—C10—H10 | 120.0 |
C2—C3—C4 | 127.5 (2) | N3—C11—C11i | 111.2 (2) |
C3—C4—H4A | 109.5 | N3—C11—H11A | 109.4 |
C3—C4—H4B | 109.5 | C11i—C11—H11A | 109.4 |
H4A—C4—H4B | 109.5 | N3—C11—H11B | 109.4 |
C3—C4—H4C | 109.5 | C11i—C11—H11B | 109.4 |
H4A—C4—H4C | 109.5 | H11A—C11—H11B | 108.0 |
H4B—C4—H4C | 109.5 | ||
C1—N1—N2—C3 | −2.0 (2) | C1—N1—C5—C10 | −130.8 (2) |
C5—N1—N2—C3 | −164.5 (2) | N2—N1—C5—C10 | 28.7 (3) |
N2—N1—C1—O1 | −177.0 (2) | C1—N1—C5—C6 | 48.4 (3) |
C5—N1—C1—O1 | −16.3 (4) | N2—N1—C5—C6 | −152.1 (2) |
N2—N1—C1—C2 | 2.0 (2) | C10—C5—C6—C7 | 2.1 (3) |
C5—N1—C1—C2 | 162.8 (2) | N1—C5—C6—C7 | −177.1 (2) |
O1—C1—C2—C3 | 177.8 (2) | C5—C6—C7—C8 | −1.2 (4) |
N1—C1—C2—C3 | −1.2 (3) | C6—C7—C8—C9 | −0.6 (4) |
N1—N2—C3—C2 | 1.3 (3) | C7—C8—C9—C10 | 1.6 (4) |
N1—N2—C3—C4 | −178.4 (2) | C8—C9—C10—C5 | −0.8 (4) |
C1—C2—C3—N2 | −0.1 (3) | C6—C5—C10—C9 | −1.1 (3) |
C1—C2—C3—C4 | 179.6 (2) | N1—C5—C10—C9 | 178.1 (2) |
Symmetry code: (i) −x+1, −y+1, −z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H3A···O1 | 0.89 | 1.94 | 2.743 (2) | 149 |
N3—H3B···O1ii | 0.89 | 1.79 | 2.672 (2) | 173 |
N3—H3C···N2iii | 0.89 | 2.04 | 2.924 (3) | 173 |
Symmetry codes: (ii) −x+1, −y+1, −z; (iii) −y+1/2, x, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C2H10N22+·2(C10H9N2O−) |
Mr | 408.50 |
Crystal system, space group | Tetragonal, P42/n |
Temperature (K) | 298 |
a, c (Å) | 17.179 (2), 7.0929 (15) |
V (Å3) | 2093.2 (6) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.24 × 0.22 × 0.17 |
Data collection | |
Diffractometer | Siemens SMART CCD area-detector diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 10541, 1856, 1284 |
Rint | 0.046 |
(sin θ/λ)max (Å−1) | 0.595 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.043, 0.141, 1.04 |
No. of reflections | 1856 |
No. of parameters | 136 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.22, −0.16 |
Computer programs: SMART (Siemens, 1996), SAINT (Siemens, 1996), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H3A···O1 | 0.89 | 1.94 | 2.743 (2) | 149.2 |
N3—H3B···O1i | 0.89 | 1.79 | 2.672 (2) | 172.9 |
N3—H3C···N2ii | 0.89 | 2.04 | 2.924 (3) | 172.5 |
Symmetry codes: (i) −x+1, −y+1, −z; (ii) −y+1/2, x, −z+1/2. |
Acknowledgements
This project was supported by the Key Project for Fundamental Research of the Jiangsu Provincial Educational Committee (07 K J A150011) and the Natural Science Foundation of the Jiangsu Provincial Educational Committee (05KJB150003)
References
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This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.
Hydrogen bonds (H-bonds) are of importance in a large number of chemical and biological processes and in many practical applications (Li et al., 2007; Peng et al., 2005; Yang et al., 2006; Yang et al., 2002). Many interesting two- and three-dimensional frameworks have been designed and produced based on H-bonds (Fu et al., 2004; Hu et al., 2004; Zhou et al., 2006). The chemistry of pyrazylone and its derivatives is particularly interesting because of their potential application in medicinal chemistry (Cerchiaro et al., 2006), so 1-phenyl-3-methyl-pyrazole-5-one (PMP), which contains imino and carbonyl groups in its heterocycle, was choosen to react with the amino groups of ethylene diamine (en). The synthesis and crystal structure of the product of this reaction are reported here.
The title compound (Fig. 1) contains two crystallographically independent ions: the [H2en]2+ cation which has two cationic ammonium groups, and the [PMP]- anion. In the [PMP]- anion, the bond length of C(1)—O(1) is 1.288 (3) Å, much shorter than that of C—O (1.43 Å), but close to that of C═O (1.22 Å) (Yang et al., 2005), indicating that the pyrazole-one ring of the title compound is present in the keto form, not the enol form. The N(2) atom of the deprotonated imino group of PMP is electron rich, therefore, the O atom of the carbonyl group and the N(2) atom of the pyrazole-one ring of the PMP molecule can be expected to be good hydrogen bond acceptors, while the H atoms of the [H2en]2+ ammonium cations are expected to be good hydrogen donors. The Jeffrey criterion for H-bonds used by the International Union of Crystallography defines the largest distance between the hydrogen and the acceptor atoms as 2.60 Å for H···O and 2.63 Å for H···N, respectively (Hernández-Galindo et al., 2007). Compared to these data, the distances of H(3)···O(1) (-x+1, -y+1/2, -z) and H(3)···N(2)(x,-y+1/2, -z+1/2) for the title compound, respectively being 1.786 Å (or 1.940 Å) and 2.039 Å, are much shorter than the above-mentioned largest limit, providing a powerful evidence of the formation of H-bonds between these separate components.
There are no covalent interactions between the separate components of the title compound, but electrostatic and H-bonding interactions are present. All H atoms of the ammonium group, the O atom of the carbonyl group and the N atom of the deprotonated imino group in the title compound are engaged in intermolecular H-bonds which link the molecule into an extended three-dimensional network (Fig. 2). The H-bonds can be clearly seen in Fig. 2 to Fig. 5, and are summarized in Table 1. There are two kinds of H-bonds in the crystal structure: N—H···O and N—H···N. As shown in Fig. 3, the oxygen atom of the carbonyl group from [PMP]- takes part in the H-bonding to the terminal nitrogen of [H2en]2+, forming intermolecular N—H···O H-bonds that result in the formation of 8-membered rings. Each of the two ammonium groups of the [H2en]2+ cation engages in these 8—membered rings, further linking the [H2en]2+ and [PMP]- ions into a two-dimensional network via these N—H···O H-bonds (Fig. 4). It can be seen from Fig. 5 that the nitrogen atom of the deprotonated imino group of [PMP]- takes part in the H-bonding to the terminal nitrogen of [H2en]2+, forming intermolecular N—H···N H-bonds. Therefore, through intermolecular N—H···O and N—H···N H-bonding interactions, each [PMP]- anion is linked to three [H2en]2+ cations and each [H2en]2+ cation to six adjacent [PMP]- anions. The two components thus construct a supramolecular assembly with a three-dimensional hydrogen bonded framework.