Skip to content
BY 4.0 license Open Access Published by De Gruyter (O) June 22, 2019

Crystal structure of dihydrazinium 1H-pyrazole-3,5-dicarboxylate, C5H12N6O4

Nedeljko Latinović, Sladjana B. Novaković, Goran A. Bogdanović, Vlatko Kastratović, Gerald Giester and Željko K. Jaćimović


C5H12N6O4, monoclinic, P21/n (no. 14), a = 4.3368(6) Å, b = 15.483(2) Å, c = 13.8852(19) Å, β = 97.714(3)°, V = 923.9(2) Å3, Z = 4, Rgt(F) = 0.0411, wRref(F2) = 0.1109, T = 200(2) K.

CCDC no.: 1910983

The asymmetric unit of the title crystal structure is shown in the figure. Table 1 contains crystallographic data and Table 2 contains the list of the atoms including atomic coordinates and displacement parameters.

Table 1:

Data collection and handling.

Crystal:Yellow prism
Size:0.22 × 0.16 × 0.07 mm
Wavelength:Mo Kα radiation (0.71073 Å)
μ:0.14 mm−1
Diffractometer, scan mode:Bruker APEX-II, φ and ω-scans
θmax, completeness:33.4°, >99%
N(hkl)measured, N(hkl)unique, Rint:32710, 3560, 0.039
Criterion for Iobs, N(hkl)gt:Iobs > 2 σ(Iobs), 2985
Programs:Bruker programs [1], SHELX [2], [3]

Table 2:

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2).


Source of material

In an attempt to synthesize the intermediates of 1H-pyrazole-3,5-dicarbohydrazide with direct synthesis starting from 3,5-pyrazoledicarboxylic acid monohydrate and hydrazine monohydrate in a stoichiometric relationship, a microcrystalline light yellow mixture was obtained with a pair of monocrystals that were mechanically isolated from the mixture and prepared for X-ray analysis.

Experimental details

All hydrogen atoms were identified in difference Fourier map and were refined isotropically.


Pyrazole-related molecules have attracted much attention because of their diverse pharmacological properties [4], and also because of their increased use in the synthesis of new functional materials [5]. The derivatives of 3,5-pyrazoledicarboxylic acid (H3PZDC) are known as building components of either purely organic or organometallic materials. As ligands the H3PZDC derivatives can display up to six metal coordination sites and various bridging modes [6] that is utilized for the synthesis of polynuclear magnetic solids [7] and MOFs [8]. On the other hand, the uncoordinated H3PZDC possesses multiple hydrogen bonding sites and can generate extensive hydrogen bonding important for supramolecular organic networks. [9] As a continuation of our research on pyrazole-derived molecules [10], [11], the present work describes the crystal structure of novel hydrazinium(+1) salt of 3,5-pyrazoledicarboxylic acid, (N2H5)2⋅HPZDC.

The crystal structures of two hydrazine salts of H3PZDC have been reported previously. These salts are of the type N2H6⋅(H2PZDC)2 [12] and N2H5⋅H2PZDC⋅H2O [9] and both contain the monocarboxylate H2PZDC anion. The asymmetric unit of title salt (N2H5)2⋅HPZDC contains the dicarboxylate dianion of H3PZDC and two hydrazinium counterions. In comparison to previous structures [12], [13] the geometry of species shows expected differences arising from their different protonation states. The crystal structure is stabilized by extensive N—H⋯O and N—H⋯N hydrogen bonding between the charged species with H⋯A distances ranging from 1.84(2) to 2.32(2) Å. The HPZDC anions alone form N1—H1⋯O1 centrosymmetric dimer [N1—H1⋯O1i = 161(2)°, H1⋯O1 = 1.98(2) Å, (i) = 2 − x, 1 − x, −z].


N⋅L. and Ž⋅K⋅J. thank to the Ministry of Science of the Republic of Montenegro for financial support (Innovative Project-Bioextra); G⋅A⋅B and S⋅B⋅N thank to the Ministry of Education, Science and Technological Development of the Republic of Serbia for financial support (Project Nos. 172014 and 172035).


1. Bruker: APEX3, SAINT-Plus, XPREP. Bruker AXS Inc., Madison, WI, USA (2016).Search in Google Scholar

2. Sheldrick, G. M.: SHELXT – Integrated space-group and crystal-structure determination. Acta Crystallogr. A71 (2015) 3–8.10.1107/S2053273314026370Search in Google Scholar PubMed PubMed Central

3. Sheldrick, G. M.: Crystal structure refinement with SHELXL. Acta Crystallogr. C71 (2015) 3–8.10.1107/S2053229614024218Search in Google Scholar PubMed PubMed Central

4. Faraz Khan, M.; Mumtaz Alam, M.; Verma, G.; Akhtar, W.; Akhter, M.; Shaquiquzzaman, M.: The therapeutic voyage of pyrazole and its analogs: A review. Europ. J. Med. Chem. 120 (2016) 170–201.10.1016/j.ejmech.2016.04.077Search in Google Scholar PubMed

5. Pettinari, C.; Tabacaru, A.; Galli, S.: Coordination polymers and metal-organic frameworks based on poly(pyrazole)-containing ligands. Coord Chem Rev. 307 (2016) 1–31.10.1016/j.ccr.2015.08.005Search in Google Scholar

6. Klingele, J.; Dechert, S.; Meyer, F.: Polynuclear transition metal complexes of metal⋯metal-bridging compartmental pyrazolate ligands. Coord. Chem. Rev. 253 (2009) 2698–2741.10.1016/j.ccr.2009.03.026Search in Google Scholar

7. Castro, I.; Barros, W. P.; Calatayud, L. M.; Lloret, F.; Marino, N.; De Munno, G.; Stumpf, H.; Ruiz-García, R.; Julve, M.: Dicopper(II) pyrazolenophanes: Ligand effects on their structures and magnetic properties. Coord. Chem. Rev. 315 (2016) 135–152.10.1016/j.ccr.2016.02.004Search in Google Scholar

8. Furukawa, H.; Gándara. F.; Zhang, Y.-B.; Jiang, J.; Queen, W. L.; Hudson, M. R.; Yaghi, O. M.: Water adsorption in porous metal-organic frameworks and related materials. J. Am. Chem. Soc. 136 (2014) 4369–4381.10.1021/ja500330aSearch in Google Scholar PubMed

9. Das, B.; Baruah, J. B.: Supramolecular synthons and hydrates in stabilization of multicomponent crystals of nicotinamide and isonicotinamide with N-containing aromatic dicarboxylic acids. Cryst. Growth Des. 11 (2011) 5522–5532.10.1021/cg201096cSearch in Google Scholar

10. Jaćimović, Ž.K.; Novaković, S. B.; Bogdanović, G. A.; Giester, G.; Kosović, M.; Libowitzky, E.: First crystal structures of metal complexes with a 4-nitropyrazole-3-carboxylic acid ligand and the third crystal form of the ligand. Acta Crystallogr. C75 (2019) 255–264.10.1107/S2053229619001244Search in Google Scholar PubMed

11. Jaćimović, Ž.; Kosović, K.; Kastratović, V.; Holló, B. B.; Szécsényi, K. M.; Szilágyi, I. M.; Latinović, N.; Vojinović-Ješić, Lj.; Rodić, M. J.: Synthesis and characterization of copper, nickel, cobalt, zinc complexes with 4-nitro-3-pyrazolecarboxylic acid ligand. Therm. Anal. Calorim. 133 (2018) 813–821.10.1007/s10973-018-7229-4Search in Google Scholar

12. Kumar Senthil, V. S.; Premkumar, T.; Rath, N. P.; Govindarajan, S.: Polymorphism in hydrazonium salt of 3,5-pyrazoledicarboxylic acid. Ind. J Chem. 46B (2007) 141–147.Search in Google Scholar

13. Premkumar, T.; Srinivasan, K.; Selvakumar, R.; Rath, N. P.; Govindarajan, S.: Synthesis, crystal structure, spectroscopic and thermal analysis of hydrazinium hydrogen-3,5-pyrazoledicarboxylate monohydrate. J. Therm. Anal. Calorim. 125 (2016) 1–9.10.1007/s10973-016-5342-9Search in Google Scholar

Received: 2019-03-06
Accepted: 2019-04-18
Published Online: 2019-06-22
Published in Print: 2019-09-25

©2019 Nedeljko Latinović et al., published by De Gruyter, Berlin/Boston

This work is licensed under the Creative Commons Attribution 4.0 Public License.