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Structure of (E)-4-amino-5-{[(1,5-di­methyl-3-oxo-2-phenyl-2,3-di­hydro-1H-pyrazol-4-yl)imino]­meth­yl}-1-methyl-2-phenyl-2,3-di­hydro-1H-pyrazol-3-one: aerial oxidation of 4-amino­anti­pyrine in di­methyl­formamide

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aDepartment of Physics, Annapoorana Engineering College (Autonomous), Salem - 636308, Tamilnadu, India, bInstitute of Physics, University of Neuchâtel, Rue Emile-Argand 11, CH-2000 Neuchâtel, Switzerland, cPG and Research Department of Physics, Srimad Andavan Arts and Science College (Autonomous), Affiliated to Bharathidasan University, Tiruchirappalli - 620005, Tamilnadu, India, dDepartment of Physics, Swami Dayananda College of Arts and Science, Affiliated to Bharathidasan University, Manjakudi - 612610, Tamilnadu, India, eInstitute of Physics ASCR, Na Slovance 2, 182 21 Praha 8, Czech Republic, fChemistry Department, University of Fribourg, Chemin du Musée 9, CH-1700 Fribourg, Switzerland, and gCrystal Growth and Thin Film Laboratory, Department of Physics, Bharathidasan University, Tiruchirappalli - 620024, Tamilnadu, India
*Correspondence e-mail: [email protected], [email protected]

Edited by W. T. A. Harrison, University of Aberdeen, United Kingdom (Received 14 April 2025; accepted 23 April 2025; online 29 April 2025)

The title compound, C22H22N6O2 (I), is the result of the aerial oxidation of the 5-methyl group of 4-amino­anti­pyrine to an aldehyde group followed by Schiff base formation with a second mol­ecule of 4-amino­anti­pyrine. The reaction only takes place in the presence of di­methyl­formamide. The central unit of the mol­ecule is close to planar, the pyrazole rings being inclined to each other by 3.74 (15)°. There is an intra­molecular N—H⋯N hydrogen bond enclosing an S(6) ring motif and there are two further S(6) rings involving weak C—H⋯O=C hydrogen bonds. The mol­ecule has an E configuration about the azomethine (—N=CH—) bond. In the crystal, inversion-related mol­ecules are linked by pairs of N—H⋯O hydrogen bonds, forming dimers enclosing R22(10) loops. The dimers are linked by C—H⋯O hydrogen bonds and C—H⋯π inter­actions, leading to the formation of a three-dimensional supra­molecular network.

1. Chemical context

The crystal structure of 4-amino­anti­pyrine (4-amino-1,5-dimethyl-2-phenyl-1,2-di­hydro-3H-pyrazol-3-one, C11H13N3O or ampyrone or 4-AAP) has been reported by Li et al. (2013[Li, Y., Liu, Y., Wang, H., Xiong, X., Wei, P. & Li, F. (2013). Molecules 18, 877-893.]) and by Mnguni & Lemmerer (2015[Mnguni, M. J. & Lemmerer, A. (2015). Acta Cryst. C71, 103-109.]), and a co-crystal of 4-AAP has been reported on by Smith & Lemmerer (2019[Smith, M. G. & Lemmerer, A. (2019). J. Mol. Struct. 1175, 307-313.]). The crystal structure of 4-(N,N-dimeth­yl)-amino­anti­pyrine was described by Singh & Vijayan (1976[Singh, T. P. & Vijayan, M. (1976). Acta Cryst. B32, 2432-2437.]). Derivatives of 4-AAP account for at least two pharmaceutical drugs, amino­anti­pyrine and 4-(N,N-dimeth­yl)-amino­anti­pyrine, both of which have been used as analgesics for over a century.

The formation of the title compound, (I), is best explained by the aerial oxidation of the 5-methyl group of 4-AAP to an aldehyde group, forming 4-amino-2-methyl-5-oxo-1-phenyl-2,5-di­hydro-1H-pyrazole-3-carbaldehyde and subsequent Schiff base formation with a second mol­ecule of 4-amino­anti­pyrine. The reactivity of the methyl group is indicated by the hyperconjugative effect and oxidation to the aldehyde by air takes place in the presence of di­methyl­formamide (DMF). The role of DMF in chemistry has been reviewed by Heravi et al. (2018[Heravi, M. M., Ghavidel, M. & Mohammadkhani, L. (2018). RSC Adv. 8, 27832-27862.]). They noted that DMF has been used as a reagent in a number of important organic reactions, such as the Vilsmeier–Haack reaction (Vilsmeier & Haack, 1927[Vilsmeier, A. & Haack, A. (1927). Ber. Dtsch. Chem. Ges. A/B 60, 119-122.]), which result in the formyl­ation of hetero-aromatic compounds

[Scheme 1]
.

Compound (I) was produced serendipitously when attempts were made to form CdCl2 or HgCl2 complexes of 4-amino­anti­pyrine (Stoeckli-Evans et al., 2025[Stoeckli-Evans, H., Shankar, M. G., Kumaravel, R., Subashini, A., Sabari Girisun, T., Ramamurthi, K., Kučeráková, M., Dušek, M. & Crochet, A. (2025). Acta Cryst. E81 393-400.]), when di­methyl­formamide (DMF) was added to the reaction mixture. When the reaction was repeated in various solvents in the absence of the metal halide, for example with methanol and aceto­nitrile or methanol and acetone, no reaction took place. It was found that compound (I) was only formed when DMF was present as one of the solvents.

To the best of our knowledge, the aerial oxidation of an amino­anti­pyrine was first reported by Kametani et al. (1967[Kametani, T., Kigasawa, K., Ikari, N., Iwata, T., Saito, M. & Yagi, H. (1967). Chem. Pharm. Bull. 15, 1305-1309.]). A yellow substance was formed as a byproduct when studying the fusion of 4-(N,N-dimeth­yl)-amino­anti­pyrine with barbital in the presence of air. To obtain a large amount of this yellow compound the reaction was repeated by introducing air into a heated solution of the amino­anti­pyrine in different solvents, such as ethanol, acetic acid or acetic anhydride. They showed by NMR and IR spectroscopic analyses that they had produced the aldehyde, 4-(di­methyl­amino)-2-methyl-5-oxo-1-phenyl-2,5-di­hydro-1H-pyrazole-3-carbaldehyde (Kametani et al., 1967[Kametani, T., Kigasawa, K., Ikari, N., Iwata, T., Saito, M. & Yagi, H. (1967). Chem. Pharm. Bull. 15, 1305-1309.]).

The result of aerial oxidation of the 5-methyl group of certain 4-amino­anti­pyrine Schiff bases to form in situ —CH2OH, —CH(OH)2 and —COOH groups has been observed in the formation of various copper(II) and cobalt(II) complexes (see §4. Database survey).

2. Structural commentary

The mol­ecular structure of (I) is illustrated in Fig. 1[link]. The central unit is close to planar with the pyrazole rings, N1/N2/C1–C3 (r.m.s. deviation = 0.036 Å) and N4/N5/C13–C15 (r.m.s. deviation = 0.035 Å), being inclined to each other by 3.74 (15)°. The planarity of the central unit is consolidated by the presence of an intra­molecular N6—H6AN⋯N3 hydrogen bond (Table 1[link]), which generates an S(6) ring motif, as do two C—H⋯O=C hydrogen bonds (Table 1[link] and Fig. 1[link]).

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of C4–C9 phenyl ring.

D—H⋯A D—H H⋯A DA D—H⋯A
N6—H6AN⋯N3 0.90 (4) 2.30 (4) 2.894 (3) 123 (3)
N6—H6BN⋯O2i 0.98 (3) 2.09 (3) 2.953 (3) 147 (3)
C7—H7⋯O2ii 0.95 2.49 3.417 (4) 165
C10—H10D⋯O2iii 0.98 2.52 3.472 (4) 164
C12—H12⋯O1 0.95 2.34 3.022 (3) 128
C17—H17⋯O2 0.95 2.55 3.013 (4) 110
C11—H11BCg1iii 0.98 2.96 3.645 (3) 128
Symmetry codes: (i) Mathematical equation; (ii) Mathematical equation; (iii) Mathematical equation.
[Figure 1]
Figure 1
A view of the mol­ecular structure of (I) with atom labelling and displacement ellipsoids drawn at the 50% probability level.

The title mol­ecule has an E configuration about the azomethine (—N3=C12H—) bond whose bond length is 1.297 (3) Å. This is slightly longer than the average value of 1.286 (6) Å (see §4. Database survey). The arene ring C4–C9 is inclined to the pyrazole ring N1/N2/C1–C3 mean plane by 55.63 (14)°, while the arene ring C16–C21 is inclined to the pyrazole ring N4/N5/C13–C15 mean plane by 32.84 (15)°. The arene rings are inclined to each other by 44.19 (4)°.

The sum of the angles subtended by the methyl substituted atom N2 is 354.9°. In contrast, the methyl-substituted N atom, N4, has a definite pyramidal geometry with the corresponding sum of angles being 328.8°. This later value is more typical and is similar to the value of 332.4° reported for 4-AAP (CSD refcode LOYXEE; Mnguni & Lemmerer, 2015[Mnguni, M. J. & Lemmerer, A. (2015). Acta Cryst. C71, 103-109.]). See also §4. Database survey.

3. Supra­molecular features

In the crystal of (I), inversion-related mol­ecules are linked by pairwise N—H⋯O hydrogen bonds, forming dimers enclosing an R22(10) ring motif (Table 1[link], Fig. 2[link]). The dimers are linked by C—H⋯O hydrogen bonds and C—H⋯π inter­actions (Table 1[link]), forming a three-dimensional supra­molecular network (Fig. 3[link]).

[Figure 2]
Figure 2
A partial view along the a axis of the crystal packing of (I). Inversion-related mol­ecules are linked by a pair of N—H⋯O hydrogen bonds (Table 1[link]), forming a dimer enclosing an R22(10) ring motif.
[Figure 3]
Figure 3
A view along the b axis of the crystal packing of (I). For clarity, only the H atoms involved in hydrogen bonding (Table 1[link]) have been included.

4. Database survey

A search of the Cambridge Structural Database (CSD, V5.46 update February 2025; Groom et al., 2016[Groom, C. R., Bruno, I. J., Lightfoot, M. P. & Ward, S. C. (2016). Acta Cryst. B72, 171-179.]) for the 4-AAP moiety gave 582 hits; 413 are organic compounds and 169 are metal–organic complexes. In a series of copper(II) and cobalt(II) complexes, in situ oxidation of the 5-methyl group of the pyrazole moiety takes place. For the copper(II) complexes (CSD refcodes: CIHPUF; Wang & Zheng, 2007[Wang, X.-W. & Zheng, Y.-Q. (2007). Inorg. Chem. Commun. 10, 709-712.] and JAXSOU; Parvarinezhad et al., 2022[Parvarinezhad, S., Salehi, M., Kubicki, M. & Eshaghi malekshah, R. (2022). J. Mol. Struct. 1260, 132780.]) the transformation is to an alcohol (—CH2OH). For the cobalt(II) complexes three transformations have been observed, to —CH2OH, —CH(OH)2 and —COOH (CSD refcodes: JUNMAI, JUNMEM and JUNMIQ; Loukopoulos et al., 2015[Loukopoulos, E., Berkoff, B., Griffiths, K., Keeble, V., Dokorou, V. N., Tsipis, A. C., Escuer, A. & Kostakis, G. E. (2015). CrystEngComm 17, 6753-6764.]). Full details and references of the CSD search are given in the supporting information.

A search of the CSD for Schiff base derivatives of 4-AAP with an —N=C— bond (with the following restrictions: three-dimensional coordinates determined, R factor ≤ 0.075, no disorder, no errors, not polymeric, no ions, single crystals only and only organics) yielded 208 hits. The analysis in Mercury (Macrae et al., 2020[Macrae, C. F., Sovago, I., Cottrell, S. J., Galek, P. T. A., McCabe, P., Pidcock, E., Platings, M., Shields, G. P., Stevens, J. S., Towler, M. & Wood, P. A. (2020). J. Appl. Cryst. 53, 226-235.]) of the —N=C— bond length found that it varies from 1.256 to 1.300 Å, with a mean value of 1.282 (6) Å. In (I) the N3=C12 bond length is slightly longer at 1.297 (3) Å. The dihedral angles involving the phenyl ring and the mean plane of the pyrazole ring vary from 32.4 to 80.2°, with an average value of 52.32 (15)°. As noted above, the corresponding values observed for the two 4-AAP moieties in (I) are 55.63 (14) and 32.84 (15)°, the latter dihedral angle being close to the lower limit value.

The pyramidal geometry of the methyl-substituted N atom of the pyrazole ring, measured by the sum of the three angles involving the N atom, was found to have a lower limit of ca 340° in the two independent mol­ecules of 4-((E)-{2-[N-(1,5-dimethyl-3-oxo-2-phenyl-2,3-di­hydro-1H-pyrazol-4-yl)-carb­oximido­yl]benzyl­idene}amino)-1,5-dimethyl-2-phenyl-2,3-di­hydro-1H-pyrazol-3-one (ABADEO; Potgieter et al., 2011[Potgieter, K., Hosten, E., Gerber, T. & Betz, R. (2011). Acta Cryst. E67, o2785-o2786.]), and a higher limit of 359.0° in {2-[(1,5-dimethyl-2-phenyl-3-oxo-2,3-di­hydro-1H-pyrazol-4-yl­imino)­meth­yl]-phen­oxy}acetic acid methanol hemisolvate (EVILOK; You et al., 2004[You, Z.-L., Zhu, H.-L. & Liu, W.-S. (2004). Acta Cryst. E60, o801-o803.]). In (I), the sum of these angles is ca 328.8° for atom N4, hence this atom is highly pyramidal (Fig. 1[link]), more so than for the N atoms in ABADEO. The value of ca 354.9° for atom N2 is close to the value of 359.0° observed in EVILOK.

Using the CSD Python API, mol­ecular similarity, only one compound was found when compared to the structure of compound (I), namely 1,5-dimethyl-2-phenyl-4-[(1H-pyrrol-2-yl-methyl­ene)amino]­pyrazol-3(2H)-one (DEXTAC; Jing & Chen, 2007[Jing, Z.-L. & Chen, X. (2007). Acta Cryst. E63, o687-o688.]), which has a similarity index of 0.726. The structural overlap of the two compounds is shown in Fig. 4[link]; the r.m.s. deviation is 0.018 Å (Mercury; Macrae et al., 2020[Macrae, C. F., Sovago, I., Cottrell, S. J., Galek, P. T. A., McCabe, P., Pidcock, E., Platings, M., Shields, G. P., Stevens, J. S., Towler, M. & Wood, P. A. (2020). J. Appl. Cryst. 53, 226-235.]). Here, the —N=C— bond length is 1.282 (1) Å and the dihedral angle involving the phenyl ring and the mean plane of the pyrazole ring is 62.5 (1)°.

[Figure 4]
Figure 4
A view of the structural overlay of (I) and DEXTAC (Jing & Chen, 2007[Jing, Z.-L. & Chen, X. (2007). Acta Cryst. E63, o687-o688.]); the r.m.s. deviation is 0.018 Å (Mercury; Macrae et al., 2020[Macrae, C. F., Sovago, I., Cottrell, S. J., Galek, P. T. A., McCabe, P., Pidcock, E., Platings, M., Shields, G. P., Stevens, J. S., Towler, M. & Wood, P. A. (2020). J. Appl. Cryst. 53, 226-235.]).

5. Hirshfeld surface analysis and two-dimensional fingerprint plots

The Hirshfeld surface analysis and the associated two-dimensional fingerprint plots were generated with CrystalExplorer17 (Spackman et al., 2021[Spackman, P. R., Turner, M. J., McKinnon, J. J., Wolff, S. K., Grimwood, D. J., Jayatilaka, D. & Spackman, M. A. (2021). J. Appl. Cryst. 54, 1006-1011.]) and interpreted following the protocol of Tan et al. (2019[Tan, S. L., Jotani, M. M. & Tiekink, E. R. T. (2019). Acta Cryst. E75, 308-318.]). The Hirshfeld surface for compound (I) is illustrated in Fig. 5[link]. The presence of prominent red spots indicates that short contacts are particularly significant in the crystal packing.

[Figure 5]
Figure 5
The Hirshfeld surface of (I), mapped over dnorm.

The full two-dimensional fingerprint plots for (I) are given in Fig. 6[link]. The H⋯H contacts have a major contribution of 52.4% to the Hirshfeld surface. The second most significant contribution is from the C⋯H/H⋯C contacts at 23.3%. The O⋯H/H⋯O contacts contribute 12.7% and have sharp pincer-like spikes at de + di ≃ 2.1 Å. The N⋯H/H⋯N contacts contribute 7.0%, and the C⋯C contacts contribute 2.6%. These values can be correlated with the various hydrogen bonds and other inter­atomic inter­actions in the crystal (Table 1[link]).

[Figure 6]
Figure 6
The full two-dimensional fingerprint plot for (I), and those delineated into H⋯H, C⋯H/H⋯C, O⋯H/H⋯O, N⋯H/H⋯N and C⋯C contacts.

6. Energy frameworks

A comparison of the energy frameworks calculated for (I), showing the electrostatic potential forces (Eele), the dispersion forces (Edis) and the total energy diagrams (Etot), are shown in Fig. 7[link]. The energies were obtained by using wave functions at the HF/3-2IG level of theory. The cylindrical radii are proportional to the relative strength of the corresponding energies (Spackman et al., 2021[Spackman, P. R., Turner, M. J., McKinnon, J. J., Wolff, S. K., Grimwood, D. J., Jayatilaka, D. & Spackman, M. A. (2021). J. Appl. Cryst. 54, 1006-1011.]; Tan et al., 2019[Tan, S. L., Jotani, M. M. & Tiekink, E. R. T. (2019). Acta Cryst. E75, 308-318.]). They have been adjusted to the same scale factor of 90 with a cut-off value of 6 kJ mol−1 within a radius of 3.8 Å of a central reference mol­ecule.

[Figure 7]
Figure 7
The energy frameworks calculated for (I), viewed along the b-axis direction, showing the electrostatic potential forces (Eele), the dispersion forces (Edis) and the total energy diagram (Etot).

The major contribution to the inter­molecular inter­actions is from dispersion forces (Edis), as expected in view of the significant contribution to the HS of the H⋯H contacts at 52.4%. The colour-coded inter­action mapping within a radius of 3.8 Å of a central reference mol­ecule and the various contributions to the total energy (Etot) for compound (I) are given in Fig. S1 of the supporting information.

7. Synthesis, spectroscopic data and thermal analysis

A solution of 0.100 mmol of 4-amino­anti­pyrine and an equimolar qu­antity of cadmium chloride (or mercury chloride) in a solvent mixture of 5 ml of methanol and 5 ml of dimethyl formamide (DMF) was refluxed at 363 K for 6 h using an oil bath. The solution was then left at room temperature for 10 days. On evaporation of the solvents reddish-brown crystals of (I) were obtained; m.p. 517–518 K. The same compound was obtained when 4-amino­anti­pyrine was refluxed in methanol and DMF in the absence of the metal chloride. When 4-amino­anti­pyrine was heated in a mixture of different solvents, it was observed that compound (I) was only produced in the presence of DMF.

The absorption spectrum of (I) was measured using a UV-Vis spectrometer in the wavelength range of 200–800 nm in CHCl3 as solvent (Fig. 8[link]a). The absorption band at 258 nm is attributed to the ππ* transitions of the aromatic rings. The second absorption band at 397 nm is due to nπ* transitions of the C=O and C=N bonds.

[Figure 8]
Figure 8
(a) The UV-vis spectrum of (I) in the range 250–800 nm, (b) the FTIR spectrum of (I) in the range 400–4000 cm−1, and (c) the 1H NMR spectrum of (I).

The FTIR spectrum of (I) was recorded using a JASCO Infrared spectrometer (KBr pellet) between 400–4000 cm−1 (Fig. 8[link]b). For the spectrum of 4-amino­anti­pyrine, see Swaminathan et al. (2009[Swaminathan, J., Ramalingam, M., Sethuraman, V., Sundaraganesan, N. & Sebastian, S. (2009). Spectrochim. Acta A Mol. Biomol. Spectrosc. 73, 593-600.]). A prominent absorption peak at 1569 cm−1 corresponding to the C=N stretching frequency confirms the formation of the Schiff base compound (I). For the NH2 group of 4-amino­anti­pyrine, strong symmetric and asymmetric stretching vibrations are observed at 3326 and 3432 cm−1. In compound (I), these vibrations are displaced and appear as medium-sized peaks at 3313 and 3421 cm−1. The C=O stretching frequency for 4-amino­anti­pyrine appears at 1679 cm−1, while for compound (I) this vibrational frequency is red shifted to 1648 cm−1. The shifts in the N—H and C=O stretching frequencies suggest a significant conjugation between these functional groups.

The 1H NMR spectrum of (I) was recorded in CDCl3 using a Bruker AC 400 MHz-NMR spectrometer (Fig. 8[link]c). The peaks at 2.43 ppm and 3.15 ppm correspond to the methyl groups (—CH3) attached to the carbon and nitro­gen atoms, respectively, of the pyrazole rings. The aromatic protons appear in their usual range of 7.15–7.8 ppm, while the methine H atom (H12) resonates at 8.25 ppm confirming the Schiff base formation. As shown by Hansen & Spanget-Larsen (2017[Hansen, P. E. & Spanget-Larsen, J. (2017). Molecules 22, 552-572.]), the presence of intra­molecular hydrogen bonding has a significant effect on the chemical shifts of the H atoms involved. The presence of the strong intra­molecular N—H⋯N hydrogen bond (N6—H6AN⋯N3) results in a shift to 15.22 ppm for this N—H proton. The resonance at 10.83 ppm can be assigned to the second H atom of the NH2 group.

An SQT Q600 V20.9 Build 20 Simultaneous Thermo Analytical system was used to measure the TGA/DTA of (I) in a nitro­gen atmosphere with a heating rate of 10°C min−1 (Fig. S2 of the supporting information). The TGA curve for (I) reveals a single-stage weight loss starting around 136°C. The compound decomposes before reaching its melting point as indicated by the DTA curve.

8. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2[link]. The amino H atoms (NH2) were located in a difference-Fourier map and freely refined. The C-bound H atoms were included in calculated positions and refined as riding, with C—H = 0.95–0.98 Å and Uiso(H) = 1.2Ueq(C) or 1.5Ueq(methyl C). The H atoms of methyl group C10 were modelled as disordered over two orientations with an AFIX 123 constraint in SHELXL.

Table 2
Experimental details

Crystal data
Chemical formula C22H22N6O2
Mr 402.45
Crystal system, space group Monoclinic, C2/c
Temperature (K) 95
a, b, c (Å) 20.2393 (11), 10.6519 (8), 19.4225 (11)
β (°) 106.614 (5)
V3) 4012.4 (4)
Z 8
Radiation type Cu Kα
μ (mm−1) 0.73
Crystal size (mm) 0.11 × 0.06 × 0.02
 
Data collection
Diffractometer SuperNova, Dual, Cu at home/near, AtlasS2
Absorption correction Multi-scan (CrysAlis PRO; Rigaku OD, 2020[Rigaku OD (2020). CrysAlis PRO. Rigaku Oxford Diffraction Ltd., Yarnton, England.])
Tmin, Tmax 0.489, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections 11696, 3915, 2695
Rint 0.078
(sin θ/λ)max−1) 0.621
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.058, 0.137, 1.09
No. of reflections 3915
No. of parameters 281
No. of restraints 3
H-atom treatment H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3) 0.23, −0.24
Computer programs: CrysAlis PRO (Rigaku OD, 2020[Rigaku OD (2020). CrysAlis PRO. Rigaku Oxford Diffraction Ltd., Yarnton, England.]), SUPERFLIP (Palatinus & Chapuis, 2007[Palatinus, L. & Chapuis, G. (2007). J. Appl. Cryst. 40, 786-790.]; JANA2020 (Petříček et al., 2023[Petříček, V., Palatinus, L., Plàšil, J. & Dusěk, M. (2023). Z. Kristallogr. 238, 271-282.]), SHELXL2019/3 (Sheldrick, 2015[Sheldrick, G. M. (2015). Acta Cryst. C71, 3-8.]), Mercury (Macrae et al., 2020[Macrae, C. F., Sovago, I., Cottrell, S. J., Galek, P. T. A., McCabe, P., Pidcock, E., Platings, M., Shields, G. P., Stevens, J. S., Towler, M. & Wood, P. A. (2020). J. Appl. Cryst. 53, 226-235.]),PLATON (Spek, 2020[Spek, A. L. (2020). Acta Cryst. E76, 1-11.]) and publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Computing details top

(E)-4-Amino-5-{[(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)imino]methyl}-1-methyl-2-phenyl-2,3-dihydro-1H-pyrazol-3-one top
Crystal data top
C22H22N6O2F(000) = 1696
Mr = 402.45Dx = 1.332 Mg m3
Monoclinic, C2/cCu Kα radiation, λ = 1.54184 Å
a = 20.2393 (11) ÅCell parameters from 2185 reflections
b = 10.6519 (8) Åθ = 4.5–73.1°
c = 19.4225 (11) ŵ = 0.73 mm1
β = 106.614 (5)°T = 95 K
V = 4012.4 (4) Å3Block, yellow
Z = 80.11 × 0.06 × 0.02 mm
Data collection top
SuperNova, Dual, Cu at home/near, AtlasS2
diffractometer
3915 independent reflections
Radiation source: micro-focus sealed X-ray tube2695 reflections with I > 2σ(I)
Mirror monochromatorRint = 0.078
Detector resolution: 5.2027 pixels mm-1θmax = 73.4°, θmin = 4.6°
ω scansh = 2024
Absorption correction: multi-scan
(CrysAlisPro; Rigaku OD, 2020)
k = 1311
Tmin = 0.489, Tmax = 1.000l = 2124
11696 measured reflections
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)] = 0.058Hydrogen site location: mixed
wR(F2) = 0.137H atoms treated by a mixture of independent and constrained refinement
S = 1.09 w = 1/[σ2(Fo2) + (0.0162P)2 + 0.9186P]
where P = (Fo2 + 2Fc2)/3
3915 reflections(Δ/σ)max < 0.001
281 parametersΔρmax = 0.23 e Å3
3 restraintsΔρmin = 0.24 e Å3
Special details top

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

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
O10.26471 (10)0.82349 (18)0.71602 (11)0.0333 (5)
O20.48785 (10)0.67524 (17)0.45511 (10)0.0270 (4)
N10.28813 (11)0.6763 (2)0.80851 (12)0.0241 (5)
N20.32274 (11)0.5621 (2)0.82181 (12)0.0239 (5)
N30.36940 (11)0.6519 (2)0.66612 (12)0.0230 (4)
N40.37734 (11)0.8631 (2)0.52073 (12)0.0241 (5)
N50.41266 (11)0.8324 (2)0.46958 (12)0.0225 (5)
N60.45817 (12)0.5646 (2)0.58278 (13)0.0264 (5)
H6AN0.4389 (19)0.534 (4)0.6156 (19)0.046 (10)*
H6BN0.4769 (18)0.506 (3)0.5546 (18)0.044 (10)*
C10.29526 (13)0.7285 (2)0.74460 (15)0.0252 (5)
C20.34215 (12)0.6435 (2)0.72408 (14)0.0220 (5)
C30.35728 (13)0.5455 (2)0.77250 (14)0.0234 (5)
C40.23438 (14)0.7031 (3)0.84031 (14)0.0258 (5)
C50.23232 (13)0.8209 (3)0.86942 (15)0.0269 (6)
H50.2654950.8826240.8671080.032*
C60.18129 (15)0.8482 (3)0.90208 (15)0.0316 (6)
H60.1794840.9290060.9221220.038*
C70.13298 (14)0.7580 (3)0.90557 (16)0.0314 (6)
H70.0984120.7769050.9283360.038*
C80.13510 (15)0.6400 (3)0.87575 (17)0.0352 (7)
H80.1019780.5781220.8780160.042*
C90.18632 (14)0.6126 (3)0.84232 (16)0.0313 (6)
H90.1878740.5325220.8212860.038*
C100.34044 (15)0.5069 (3)0.89333 (14)0.0300 (6)
H10A0.3069590.5340450.9180950.045*0.5
H10B0.3395650.4151770.8893500.045*0.5
H10C0.3867060.5343820.9206920.045*0.5
H10D0.3818610.4550240.9006630.045*0.5
H10E0.3492550.5738920.9294080.045*0.5
H10F0.3021140.4546870.8980650.045*0.5
C110.40348 (15)0.4365 (3)0.77530 (15)0.0290 (6)
H11A0.4277370.4461430.7385860.043*
H11B0.3760960.3592080.7662910.043*
H11C0.4371390.4321140.8228840.043*
C120.35777 (13)0.7508 (2)0.62549 (14)0.0222 (5)
H120.3306120.8180760.6345770.027*
C130.38717 (13)0.7557 (2)0.56620 (14)0.0237 (5)
C140.42913 (13)0.6708 (2)0.54780 (13)0.0212 (5)
C150.44761 (13)0.7201 (2)0.48601 (14)0.0236 (5)
C160.42297 (13)0.9285 (2)0.42269 (14)0.0239 (5)
C170.43325 (16)0.8949 (3)0.35769 (15)0.0341 (6)
H170.4334880.8090000.3445280.041*
C180.44319 (18)0.9885 (3)0.31212 (17)0.0408 (7)
H180.4503610.9660700.2674630.049*
C190.44287 (15)1.1135 (3)0.33029 (17)0.0343 (7)
H190.4504481.1766860.2988910.041*
C200.43135 (14)1.1456 (3)0.39494 (15)0.0283 (6)
H200.4292851.2317220.4069670.034*
C210.42279 (13)1.0542 (2)0.44233 (14)0.0252 (5)
H210.4168841.0768690.4875120.030*
C220.30443 (14)0.8929 (3)0.48461 (18)0.0376 (7)
H22A0.2799790.9070240.5207990.056*
H22B0.2830730.8226850.4536020.056*
H22C0.3018220.9688350.4554450.056*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0366 (11)0.0269 (10)0.0438 (12)0.0139 (8)0.0232 (9)0.0129 (9)
O20.0314 (10)0.0231 (9)0.0313 (10)0.0013 (7)0.0166 (8)0.0011 (7)
N10.0262 (11)0.0212 (10)0.0297 (12)0.0040 (8)0.0158 (9)0.0056 (9)
N20.0259 (11)0.0212 (10)0.0268 (11)0.0024 (8)0.0112 (9)0.0030 (9)
N30.0220 (10)0.0235 (10)0.0257 (11)0.0008 (8)0.0104 (9)0.0009 (9)
N40.0247 (11)0.0252 (11)0.0271 (12)0.0037 (8)0.0147 (9)0.0036 (9)
N50.0257 (11)0.0219 (10)0.0229 (11)0.0015 (8)0.0117 (9)0.0014 (8)
N60.0336 (12)0.0194 (11)0.0300 (13)0.0049 (9)0.0150 (10)0.0034 (9)
C10.0249 (13)0.0262 (13)0.0279 (13)0.0016 (10)0.0131 (11)0.0021 (11)
C20.0205 (12)0.0208 (11)0.0276 (13)0.0023 (9)0.0113 (10)0.0024 (10)
C30.0234 (12)0.0233 (12)0.0242 (13)0.0000 (10)0.0082 (10)0.0012 (10)
C40.0272 (13)0.0274 (13)0.0258 (13)0.0016 (10)0.0126 (11)0.0014 (11)
C50.0231 (13)0.0290 (14)0.0306 (14)0.0025 (10)0.0108 (11)0.0052 (11)
C60.0340 (15)0.0327 (15)0.0297 (15)0.0031 (12)0.0117 (12)0.0034 (12)
C70.0304 (14)0.0352 (15)0.0350 (15)0.0070 (12)0.0194 (12)0.0056 (12)
C80.0344 (16)0.0348 (15)0.0440 (18)0.0013 (12)0.0237 (14)0.0041 (13)
C90.0316 (14)0.0259 (13)0.0420 (17)0.0008 (11)0.0192 (13)0.0010 (12)
C100.0331 (15)0.0333 (15)0.0265 (14)0.0036 (11)0.0132 (12)0.0065 (11)
C110.0334 (14)0.0288 (14)0.0264 (14)0.0073 (11)0.0110 (11)0.0005 (11)
C120.0230 (12)0.0204 (12)0.0260 (13)0.0014 (9)0.0113 (10)0.0006 (10)
C130.0231 (12)0.0222 (12)0.0273 (13)0.0022 (10)0.0098 (10)0.0028 (10)
C140.0211 (12)0.0209 (12)0.0228 (12)0.0015 (9)0.0081 (10)0.0019 (9)
C150.0248 (13)0.0211 (12)0.0269 (13)0.0019 (10)0.0107 (10)0.0018 (10)
C160.0237 (12)0.0245 (13)0.0246 (13)0.0033 (10)0.0087 (10)0.0021 (10)
C170.0455 (17)0.0323 (15)0.0263 (14)0.0004 (13)0.0129 (13)0.0022 (12)
C180.0512 (19)0.0448 (18)0.0308 (15)0.0003 (14)0.0188 (14)0.0052 (13)
C190.0315 (14)0.0362 (15)0.0371 (16)0.0011 (12)0.0129 (12)0.0131 (13)
C200.0258 (13)0.0241 (13)0.0343 (15)0.0009 (10)0.0075 (11)0.0060 (11)
C210.0217 (12)0.0269 (13)0.0260 (13)0.0013 (10)0.0054 (11)0.0016 (10)
C220.0264 (14)0.0427 (17)0.0475 (19)0.0063 (12)0.0169 (13)0.0162 (14)
Geometric parameters (Å, º) top
O1—C11.232 (3)C8—H80.9500
O2—C151.237 (3)C9—H90.9500
N1—N21.390 (3)C10—H10A0.9800
N1—C11.405 (3)C10—H10B0.9800
N1—C41.425 (3)C10—H10C0.9800
N2—C31.349 (4)C10—H10D0.9800
N2—C101.455 (3)C10—H10E0.9800
N3—C121.297 (3)C10—H10F0.9800
N3—C21.391 (3)C11—H11A0.9800
N4—N51.418 (3)C11—H11B0.9800
N4—C131.424 (3)C11—H11C0.9800
N4—C221.476 (3)C12—C131.441 (4)
N5—C151.379 (3)C12—H120.9500
N5—C161.425 (3)C13—C141.357 (4)
N6—C141.364 (3)C14—C151.454 (4)
N6—H6AN0.90 (4)C16—C171.384 (4)
N6—H6BN0.98 (4)C16—C211.393 (4)
C1—C21.447 (4)C17—C181.386 (4)
C2—C31.379 (4)C17—H170.9500
C3—C111.482 (4)C18—C191.378 (5)
C4—C91.378 (4)C18—H180.9500
C4—C51.382 (4)C19—C201.384 (4)
C5—C61.389 (4)C19—H190.9500
C5—H50.9500C20—C211.385 (4)
C6—C71.386 (4)C20—H200.9500
C6—H60.9500C21—H210.9500
C7—C81.390 (4)C22—H22A0.9800
C7—H70.9500C22—H22B0.9800
C8—C91.402 (4)C22—H22C0.9800
N2—N1—C1109.7 (2)H10A—C10—H10C109.5
N2—N1—C4120.1 (2)H10B—C10—H10C109.5
C1—N1—C4126.0 (2)H10D—C10—H10E109.5
C3—N2—N1108.5 (2)H10D—C10—H10F109.5
C3—N2—C10126.1 (2)H10E—C10—H10F109.5
N1—N2—C10120.3 (2)C3—C11—H11A109.5
C12—N3—C2120.0 (2)C3—C11—H11B109.5
N5—N4—C13103.86 (19)H11A—C11—H11B109.5
N5—N4—C22110.6 (2)C3—C11—H11C109.5
C13—N4—C22114.3 (2)H11A—C11—H11C109.5
C15—N5—N4111.5 (2)H11B—C11—H11C109.5
C15—N5—C16127.7 (2)N3—C12—C13118.1 (2)
N4—N5—C16118.5 (2)N3—C12—H12120.9
C14—N6—H6AN116 (2)C13—C12—H12120.9
C14—N6—H6BN116 (2)C14—C13—N4111.0 (2)
H6AN—N6—H6BN119 (3)C14—C13—C12128.2 (2)
O1—C1—N1123.9 (2)N4—C13—C12120.6 (2)
O1—C1—C2132.3 (3)C13—C14—N6129.4 (3)
N1—C1—C2103.7 (2)C13—C14—C15107.8 (2)
C3—C2—N3122.6 (2)N6—C14—C15122.4 (2)
C3—C2—C1108.7 (2)O2—C15—N5126.0 (2)
N3—C2—C1128.7 (2)O2—C15—C14128.4 (2)
N2—C3—C2109.0 (2)N5—C15—C14105.5 (2)
N2—C3—C11121.7 (2)C17—C16—C21120.8 (3)
C2—C3—C11129.3 (3)C17—C16—N5119.0 (2)
C9—C4—C5121.3 (3)C21—C16—N5120.2 (2)
C9—C4—N1120.3 (2)C16—C17—C18118.9 (3)
C5—C4—N1118.4 (2)C16—C17—H17120.5
C4—C5—C6119.4 (3)C18—C17—H17120.5
C4—C5—H5120.3C19—C18—C17121.3 (3)
C6—C5—H5120.3C19—C18—H18119.3
C7—C6—C5120.3 (3)C17—C18—H18119.3
C7—C6—H6119.8C18—C19—C20119.1 (3)
C5—C6—H6119.8C18—C19—H19120.5
C6—C7—C8120.0 (3)C20—C19—H19120.5
C6—C7—H7120.0C19—C20—C21121.0 (3)
C8—C7—H7120.0C19—C20—H20119.5
C7—C8—C9119.7 (3)C21—C20—H20119.5
C7—C8—H8120.1C20—C21—C16118.9 (3)
C9—C8—H8120.1C20—C21—H21120.5
C4—C9—C8119.3 (3)C16—C21—H21120.5
C4—C9—H9120.4N4—C22—H22A109.5
C8—C9—H9120.4N4—C22—H22B109.5
N2—C10—H10A109.5H22A—C22—H22B109.5
N2—C10—H10B109.5N4—C22—H22C109.5
H10A—C10—H10B109.5H22A—C22—H22C109.5
N2—C10—H10C109.5H22B—C22—H22C109.5
C1—N1—N2—C35.9 (3)C5—C4—C9—C81.2 (4)
C4—N1—N2—C3164.2 (2)N1—C4—C9—C8178.2 (3)
C1—N1—N2—C10162.1 (2)C7—C8—C9—C40.7 (5)
C4—N1—N2—C1039.7 (3)C2—N3—C12—C13179.8 (2)
C13—N4—N5—C155.6 (3)N5—N4—C13—C144.3 (3)
C22—N4—N5—C15128.7 (2)C22—N4—C13—C14124.9 (3)
C13—N4—N5—C16169.6 (2)N5—N4—C13—C12179.4 (2)
C22—N4—N5—C1667.3 (3)C22—N4—C13—C1258.8 (3)
N2—N1—C1—O1173.0 (3)N3—C12—C13—C143.0 (4)
C4—N1—C1—O116.3 (4)N3—C12—C13—N4178.6 (2)
N2—N1—C1—C25.3 (3)N4—C13—C14—N6170.8 (3)
C4—N1—C1—C2162.0 (2)C12—C13—C14—N65.2 (5)
C12—N3—C2—C3174.6 (2)N4—C13—C14—C151.5 (3)
C12—N3—C2—C15.8 (4)C12—C13—C14—C15177.4 (3)
O1—C1—C2—C3175.1 (3)N4—N5—C15—O2172.9 (2)
N1—C1—C2—C32.9 (3)C16—N5—C15—O210.8 (4)
O1—C1—C2—N34.5 (5)N4—N5—C15—C144.9 (3)
N1—C1—C2—N3177.4 (2)C16—N5—C15—C14167.0 (2)
N1—N2—C3—C23.9 (3)C13—C14—C15—O2175.7 (3)
C10—N2—C3—C2158.3 (2)N6—C14—C15—O22.8 (4)
N1—N2—C3—C11175.5 (2)C13—C14—C15—N52.0 (3)
C10—N2—C3—C1121.1 (4)N6—C14—C15—N5174.9 (2)
N3—C2—C3—N2179.1 (2)C15—N5—C16—C1742.4 (4)
C1—C2—C3—N20.5 (3)N4—N5—C16—C17156.5 (2)
N3—C2—C3—C111.5 (4)C15—N5—C16—C21137.4 (3)
C1—C2—C3—C11178.9 (3)N4—N5—C16—C2123.7 (3)
N2—N1—C4—C942.8 (4)C21—C16—C17—C180.2 (4)
C1—N1—C4—C9111.6 (3)N5—C16—C17—C18179.9 (3)
N2—N1—C4—C5136.5 (3)C16—C17—C18—C190.1 (5)
C1—N1—C4—C569.0 (4)C17—C18—C19—C201.0 (5)
C9—C4—C5—C60.7 (4)C18—C19—C20—C212.4 (4)
N1—C4—C5—C6178.6 (3)C19—C20—C21—C162.7 (4)
C4—C5—C6—C70.1 (4)C17—C16—C21—C201.6 (4)
C5—C6—C7—C80.5 (4)N5—C16—C21—C20178.5 (2)
C6—C7—C8—C90.1 (5)
Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of C4–C9 phenyl ring.
D—H···AD—HH···AD···AD—H···A
N6—H6AN···N30.90 (4)2.30 (4)2.894 (3)123 (3)
N6—H6BN···O2i0.98 (3)2.09 (3)2.953 (3)147 (3)
C7—H7···O2ii0.952.493.417 (4)165
C10—H10D···O2iii0.982.523.472 (4)164
C12—H12···O10.952.343.022 (3)128
C17—H17···O20.952.553.013 (4)110
C11—H11B···Cg1iii0.982.963.645 (3)128
Symmetry codes: (i) x+1, y+1, z+1; (ii) x1/2, y+3/2, z+1/2; (iii) x, y+1, z+1/2.
 

Acknowledgements

AS thanks Professor K. Panchanatheswaran, Former Professor, Department of Chemistry, Bharathidasan University, Tiruchirappalli-24, and Dr P. Venkatesan, Assistant Professor of Chemistry, Srimad Andavan Arts and Science College (A), Tiruchirappalli-5, for many fruitful discussions. MK and MD acknowledge using the CzechNanoLab Research Infrastructure supported by MEYS CR (No. LM2018110) for crystallographic analysis. HSE is grateful to the University of Neuchâtel for their support over the years.

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