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ISSN: 2056-9890

Synthesis, crystal structure and Hirshfeld surface analysis of di­methyl 3-(3-bromo­phen­yl)-6-methyl-7-oxo-3,5,6,7-tetra­hydro­pyrazolo­[1,2-a]pyrazole-1,2-di­carboxyl­ate

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aLaboratory of Molecular Chemistry, Materials and Catalysis, Faculty of Sciences and Technics, Sultan Moulay Slimane University, Béni-Mellal, BP 523, Morocco, bDépartement de Chimie, Faculté des Sciences Appliquées Ait Melloul, Université IBN ZOHR, N10. BP 6146 Cité Azrou, Ait Melloul, 86150 Agadir, Morocco, cHigher School of Technology, Sultan Moulay Slimane University, BP 336, Fkih Ben Salah, Morocco, and dLaboratoire de Chimie Appliquée des Matériaux, Centre des Sciences des Matériaux, Faculty of Science, Mohammed V University in Rabat, Avenue Ibn Batouta, BP 1014, Rabat, Morocco
*Correspondence e-mail: r_elajlaoui@yahoo.com

Edited by W. T. A. Harrison, University of Aberdeen, Scotland (Received 21 December 2021; accepted 27 December 2021; online 7 January 2022)

The title compound, C17H17BrN2O5, resulted from the 1,3-dipolar cyclo­addition reaction between dimethyl acetyl­enedi­carboxyl­ate and (3-bromo­benzyl­idene)-4-methyl-5-oxopyrazolidin-2-ium-1-ide in CHCl3. The dihedral angle between the pyrazole rings (all atoms) is 32.91 (10)°; the oxo-pyrazole ring displays an envelope conformation whereas the other pyrazole ring adopts a twisted conformation. The bromo­phenyl ring subtends a dihedral angle of 88.95 (9)° with the mean plane of its attached pyrazole ring. In the crystal, the mol­ecules are linked by C—H⋯O hydrogen bonds and aromatic ππ inter­actions with an inter-centroid distance of 3.8369 (10) Å. The Hirshfeld surface analysis and fingerprint plots reveal that the mol­ecular packing is governed by H⋯H (37.1%), O⋯H/H⋯O (31.3%), Br⋯H/H⋯Br (13.5%) and C⋯H/H⋯C (10.6%) contacts. The energy framework indicates that dispersion energy is the major contributor to the mol­ecular packing.

1. Chemical context

Tetra­hydro­pyrazolo­[1,2-a] pyrazolo­nes have been studied for about forty years as analogues of penicillin and cephalosporin anti­biotics (Jungheim & Sigmund, 1987[Jungheim, L. N. & Sigmund, S. K. (1987). J. Org. Chem. 52, 4007-4013.]; Jungheim et al., 1987[Jungheim, L. N., Sigmund, S. K. & Fisher, J. W. (1987). Tetrahedron Lett. 28, 285-288.]; Ternansky et al., 1993[Ternansky, R. J., Draheim, S. E., Pike, A. J., Counter, F. T., Eudaly, J. A. & Kasher, J. S. (1993). J. Med. Chem. 36, 3224-3229.]; Konaklieva & Plotkin, 2003[Konaklieva, M. I. & Plotkin, B. J. (2003). Current Medicinal Chemistry - Anti-Infective Agents 2; 287-302.]; Hanessian et al., 1997[Hanessian, S., McNaughton-Smith, G., Lombart, H. G. & Lubell, W. D. (1997). Tetrahedron, 53, 12789-12854.]) and have been developed as herbicides and pesticides (Kosower et al., 1995[Kosower, E. M., Radkowsky, A. E., Fairlamb, A. H., Croft, S. L. & Neal, R. (1995). Eur. J. Med. Chem. 30, 659-671.]), as anti­tumor agents and as potent drugs for the treatment of cognitive dysfunctions such as Alzhheimer's disease. Among a variety of reported synthetic approaches to these compounds (Khidre et al., 2013[Khidre, R., Mohamed, H. A. & Abdel-Wahab, B. F. (2013). Turk. J. Chem. 37, 1-35.]; Li & Zhao, 2014[Li, M. & Zhao, B. X. (2014). Eur. J. Med. Chem. 85, 311-340.]; Svete, 2006[Svete, J. (2006). Arkivoc,VII, 35-56.]), 1,3-dipolar cyclo­addition has been shown to be effective (Stanley & Sibi, 2008[Stanley, L. M. & Sibi, M. P. (2008). Chem. Rev. 108, 2887-2902.]; Kissane & Maguire, 2010[Kissane, M. & Maguire, A. R. (2010). Chem. Soc. Rev. 39, 845-883.]; Pellissier, 2012[Pellissier, H. (2012). Tetrahedron, 68, 2197-2232.]). Until now, several 1,3-dipoles, such as azomethine ylides (El Ajlaoui et al., 2015[El Ajlaoui, R., Ouafa, A., Mojahidi, S., El Ammari, L., Saadi, M. & El Mostapha, R. (2015). Synth. Commun. 45, 2035-2042.]), nitro­nes (Jen et al., 2000[Jen, W. S., Wiener, J. J. M. & MacMillan, D. W. C. (2000). J. Am. Chem. Soc. 122, 9874-9875.]; Kano et al., 2005[Kano, T., Hashimoto, T. & Maruoka, K. (2005). J. Am. Chem. Soc. 127, 11926-11927.]; Suga et al., 2005[Suga, H., Nakajima, T., Itoh, K. & Kakehi, A. (2005). Org. Lett. 7, 1431-1434.]) and carbonyl ylides (Suga et al., 2007[Suga, H., Ishimoto, D., Higuchi, S., Ohtsuka, M., Arikawa, T., Tsuchida, T., Kakehi, A. & Baba, T. (2007). Org. Lett. 9, 4359-4362.]; Nambu et al., 2009[Nambu, H., Hikime, M., Krishnamurthi, J., Kamiya, M., Shimada, N. & Hashimoto, S. (2009). Tetrahedron Lett. 50, 3675-3678.]; Padwa 2011[Padwa, A. (2011). Tetrahedron, 67, 8057-8072.]), have been studied. Among them, N,N′-cyclic azomethine imines (Stanovnik et al., 1998[Stanovnik, B., Jelen, B., Turk, C., Žličar, M. & Svete, J. (1998). J. Heterocycl. Chem. 35, 1187-1204.]; Qiu et al., 2014[Qiu, G., Kuang, Y. & Wu, J. (2014). Adv. Synth. Catal. 356, 3483-3504.]; Nájera et al., 2015[Nájera, C., Sansano, J. M. & Yus, M. (2015). Org. Biomol. Chem. 13, 8596-8636.]; Xu & Doyle, 2014[Xu, X. & Doyle, M. P. (2014). Acc. Chem. Res. 47, 1396-1405.]), have been increasingly employed in cyclo­additions for the synthesis of pyrazolo­nes and the related di­nitro­gen-fused heterocyclic derivatives with significant biological activities (Ternansky et al., 1993[Ternansky, R. J., Draheim, S. E., Pike, A. J., Counter, F. T., Eudaly, J. A. & Kasher, J. S. (1993). J. Med. Chem. 36, 3224-3229.]; Boyd, 1993[Boyd, D. B. (1993). J. Med. Chem. 36, 1443-1449.]; Muehlebach, et al., 2009[Muehlebach, M., Boeger, M., Cederbaum, F., Cornes, D., Friedmann, A. A., Glock, J., Niderman, T., Stoller, A. & Wagner, T. (2009). Bioorg. Med. Chem. 17, 4241-4256.]).

As part of our studies in this area, the title compound was synthesized and its mol­ecular and crystal structure and Hirshfeld surface analysis are reported herein.

[Scheme 1]

2. Structural commentary

The mol­ecular structure of the the title compound is shown in Fig. 1[link]. There are two stereogenic centres at C2 and C5: in the arbitrarily chosen asymmetric mol­ecule, they have configurations of S and R, respectively, but a racemic mixture in the crystal is generated in the centrosymmetric P[\overline{1}] space group. The structure is characterized by a disorder of the Br atom over two adjacent sites [Br⋯Br = 0.32 (2) Å]. The dihedral angle between the fused pyrazole rings (all atoms) is 32.91 (10)°. The C1–C3/N1/N2 oxo-pyrazole ring displays an envelope conformation on C3 whereas the C5–C7/N1/N2 pyrazole ring is twisted on N2—C5, as indicated by the following respective puckering parameters: Q(2) = 0.2339 (19) Å, φ(2) = 257.9 (4)° and Q(2) = 0.2127 (16) Å, φ(2) = 50.5 (4)°. Moreover, the mean plane passing through the oxo-pyrazole ring subtends a dihedral angle of 61.15 (10)° with the C12–C17 bromo­phenyl ring, which is practically perpendicular to the other pyrazole ring as indicated by the dihedral angle of 88.95 (9)°. The non-H atoms of the ester groups are virtually coplanar, the maximum deviations from the mean planes being 0.017 (2) Å at C10 for the O2/O3/C10/C11 grouping and 0.013 (1) Å at O5 for the O4/O5/C8/C9 grouping. The dihedral angle between these two planes is 62.15 (12)°.

[Figure 1]
Figure 1
The mol­ecular structure of the title compound showing displacement ellipsoids drawn at the 50% probability level.

3. Supra­molecular features

In the crystal, the mol­ecules are linked by C—H⋯O hydrogen bonds: O1 accepts two such bonds and O2 and O3 accept one each (Table 1[link] and Fig. 2[link]). The bromo­phenyl rings of adjacent mol­ecules are linked by an aromatic stacking ππ inter­action with an inter-centroid distance of 3.8369 (10) Å.

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C9—H9A⋯O1i 0.96 2.42 3.258 (3) 146
C14—H14⋯O1ii 0.93 2.53 3.418 (2) 161
C11—H11B⋯O2iii 0.96 2.60 3.533 (3) 164
C3—H3B⋯O2iv 0.97 2.62 3.514 (3) 154
Symmetry codes: (i) [-x+1, -y+1, -z+2]; (ii) [x, y, z-1]; (iii) [-x, -y+1, -z+1]; (iv) [-x+1, -y+1, -z+1].
[Figure 2]
Figure 2
Crystal packing for the title compound showing hydrogen bonds as dashed blue lines.

4. Database survey

A search of the Cambridge Structural Database (CSD, version 5.42, update of May 2021; Groom et al., 2016[Groom, C. R., Bruno, I. J., Lightfoot, M. P. & Ward, S. C. (2016). Acta Cryst. B72, 171-179.]) for the pyrazole-1,2-di­carboxyl­ate unit revealed only one hit, namely refcode RICFUF: dimethyl 3-(tert-butyl­amino)-7-phenyl-5-oxo-1H,5H-pyrazolo­[1,2-a]pyrazole-1,2-di­carboxyl­ate (Abbasi et al., 2007[Abbasi, A., Adib, M. & Eriksson, L. (2007). Acta Cryst. E63, o2115-o2116.]). The conformations of the fused pyrazole rings present in this compound and those of the title compound are different. Furthermore, the values of the dihedral angles between the planes passing through the rings are also very different, except for the angles between the fused pyrazole rings, the difference of which does not exceed one degree, i.e. 34.13° in RICFUF and 32.91 (10)° in the title compound. It may be noted that the phenyl substituent is linked to the oxo-pyrazole ring and the two carboxyl­ate groups to the other pyrazole ring in RICFUF, while in the title compound the phenyl and both carboxyl­ate groups are linked to the same pyrazole ring.

5. Computational chemistry

Hirshfeld surface analysis

The Hirshfeld surface (HS) analyses (Spackman & Jayatilaka, 2009[Spackman, M. A. & Jayatilaka, D. (2009). CrystEngComm, 11, 19-32.]) and two-dimensional fingerprint plots (McKinnon et al., 2007[McKinnon, J. J., Jayatilaka, D. & Spackman, M. A. (2007). Chem. Commun. pp. 3814.]) generated using CrystalExplorer17.5 (Turner et al., 2017[Turner, M. J., MacKinnon, J. J., Wolff, S. K., Grimwood, D. J., Spackman, P. R., Jayatilaka, D. & Spackman, M. A. (2017). Crystal Explorer17.5. University of Western Australia, Perth, Australia.]) show the various inter­molecular inter­actions in the crystal structure. The three-dimensional dnorm surface of the title compound using a standard surface resolution with a fixed colour scale of −0.21 to 1.38 a.u is shown in Fig. 3[link]a,b. The intense red spots on the surface are due to the C—H⋯O hydrogen bonds and C—H⋯Br contacts. The bright-red spots in Fig. 3[link]c indicate atoms with the potential to be hydrogen-bond acceptors (negative electrostatic potential), while blue regions indicate atoms with positive electrostatic potential (hydrogen-bond donors) (Spackman et al., 2008[Spackman, M. A., McKinnon, J. J. & Jayatilaka, D. (2008). CrystEngComm, 10, 377-388.]).

[Figure 3]
Figure 3
Hirshfeld surfaces of the title compound mapped over (a) and (b) dnorm to visualize the inter­molecular C—H⋯O and Br⋯O contacts and (c) electrostatic potential energy using the STO-3 G basis set at the Hartree–Fock level.

Two-dimensional fingerprint plots for the H⋯H, H⋯O/O⋯H, H⋯Br/Br⋯H and H⋯C/C⋯H contacts are presented in Fig. 4[link]. The most important inter­action is H⋯H (de = di = 1.15 Å) (Fig. 4[link]b), contributing 37.6% to the overall crystal packing, which is reflected as widely scattered points of high density due to the large hydrogen content of the mol­ecule. The contribution from the O⋯H/H⋯O contacts (31.4%), corresponding to C—H⋯O inter­actions, is represented by a pair of sharp spikes characteristic of a strong hydrogen-bond inter­action (di + de = 2.40 Å, Fig. 4[link]c). The reciprocal H⋯Br/Br⋯H inter­actions (12.8%) are present as two symmetrical broad wings with di + de = 3.10 Å (Fig. 4[link]d). The C⋯H/H⋯C contacts contribute 10.8% to the Hirshfeld surface, featuring a wide region with di + de = 2.95 Å (Fig. 4[link]e). The smaller percentage contributions of other types of contact are listed in Table 2[link].

Table 2
Percentage contributions of inter­atomic contacts to the Hirshfeld surface of the title compound

Contact Percentage contribution
H⋯H 37.1
O⋯H/H⋯O 31.3
Br⋯H/H⋯Br 13.5
C⋯H/H⋯C 10.6
N⋯H/H⋯N 2.1
O⋯Br/Br⋯O 1.9
C⋯C 1.9
C⋯N/N⋯C 0.7
O⋯N/N⋯O 0.3
Br⋯Br 0.3
N⋯N 0.2
[Figure 4]
Figure 4
Two-dimensional fingerprint plots for the title compound showing (a) all inter­actions, and delineated into (b) H⋯H, (c) H⋯O/O⋯H, (d) H⋯Br/Br⋯H and (e) H⋯C/C⋯H inter­actions.

Inter­action energy calculations

The inter­molecular inter­action energies between mol­ecules in the title compound computed using a B3LYP/6–31G (d, p) energy model available in Crystal Explorer 17.5 (Turner et al., 2017[Turner, M. J., MacKinnon, J. J., Wolff, S. K., Grimwood, D. J., Spackman, P. R., Jayatilaka, D. & Spackman, M. A. (2017). Crystal Explorer17.5. University of Western Australia, Perth, Australia.]), where a cluster of mol­ecules was generated within a radius of 3.8 Å by default. The total inter­molecular energy (Etot) is the sum of electrostatic (Eele), polarization (Epol), dispersion (Edis), and exchange-repulsion (Erep) energies. The energy frameworks, which provide a view of the supra­molecular architecture of crystals, are represented by cylinders joining the centroids of mol­ecular pairs using red, green and, blue colour codes for the Eele, Edis, and Etot energy components, respectively, with a cut-off value of 5 kJ mol−1 and a scale factor of 80 to all energy components (Fig. 5[link]). The benchmarked energies Eele, Epol, Edis and Erep were scaled as 1.057, 0.740, 0.871 and 0.618, respectively (Mackenzie et al., 2017[Mackenzie, C. F., Spackman, P. R., Jayatilaka, D. & Spackman, M. A. (2017). IUCrJ, 4, 575-587.]). The nature and strength of the energies for the key identified inter­molecular inter­actions are summarized in Table 3[link]. The computed inter­action energies for electrostatic, polarization, dispersion and exchange repulsion are −107.7 kJ mol−1, −33.9 kJ mol−1, −299.7 kJ mol−1 and 185.2 kJ mol−1, respectively. These data reveal that the dispersive component makes the major contribution to the inter­molecular inter­actions in the crystal. The calculations showed that the C3—H3B⋯O2 hydrogen bond has the greatest energy among all close contacts present in the crystal with its energy (–52.1 kJ mol−1) having a major electrostatic contribution (–21.9 kJ mol−1). The next most significant contribution, with a total energy of −34.9 kJ mol−1, arises from the C11—H11B⋯O2 hydrogen bond. Lower energies, compared to the above inter­actions, are calculated for the Br1A⋯O4, C9—H9A⋯O1 and C14—H14⋯O1 contacts.

Table 3
Summary of inter­action energies (kJ mol−1) calculated for the title compound

Contact R (Å) Eele Epot Edis Erep Etot Symmetry code
C11—H11B⋯O2 7.99 −15.9 −3.6 −36.5 26.5 −34.9 -x, −y, −z
C3—H3B⋯O2 6.38 −21.9 −6.9 −54.4 38.0 −52.1 -x, −y, −z
C14—H14⋯O1 11.09 −9.3 −2.6 −11.7 9.8 −15.9 x, y, z
C9—H9A⋯O1 11.96 −17.2 −4.4 −16.6 21.4 −22.6 -x, −y, −z
Br1A⋯O4 10.81 −14.3 −4.0 −22.4 15.9 −27.7 -x, −y, −z
[Figure 5]
Figure 5
Energy framework of the title compound viewed along [001] showing (a) Coulombic energy, (b) dispersion energy and (c) total energy.

Frontier mol­ecular orbital (FMO) calculations

The optimized structure of the title compound was established in the gas phase using density functional theory (DFT) using the B3LYP exchange correlation functional and basis-set calculations (Becke, 1993[Becke, A. D. (1993). J. Chem. Phys. 98, 5648-5652.]) as implanted in GAUSSIAN 09 (Frisch et al., 2009[Frisch, M. J., Trucks, G. W., Schlegel, H. B., Scuseria, G. E., Robb, M. A., Cheeseman, J. R., Scalmani, G., Barone, V., Mennucci, B., Petersson, G. A., Nakatsuji, H., Caricato, M., Li, X., Hratchian, H. P., Izmaylov, A. F., Bloino, J., Zheng, G., Sonnenberg, J. L., Hada, M., Ehara, M., Toyota, K., Fukuda, R., Hasegawa, J., Ishida, M., Nakajima, T., Honda, Y., Kitao, O., Nakai, H., Vreven, T., Montgomery, J. A., Jr., Peralta, J. E., Ogliaro, F., Bearpark, M., Heyd, J. J., Brothers, E., Kudin, K. N., Staroverov, V. N., Kobayashi, R., Normand, J., Raghavachari, K., Rendell, A., Burant, J. C., Iyengar, S. S., Tomasi, J., Cossi, M., Rega, N., Millam, J. M., Klene, M., Knox, J. E., Cross, J. B., Bakken, V., Adamo, C., Jaramillo, J., Gomperts, R., Stratmann, R. E., Yazyev, O., Austin, A. J., Cammi, R., Pomelli, C., Ochterski, J. W., Martin, R. L., Morokuma, K., Zakrzewski, V. G., Voth, G. A., Salvador, P., Dannenberg, J. J., Dapprich, S., Daniels, A. D., Farkas, Ö., Foresman, J. B., Ortiz, J. V., Cioslowski, J. & Fox, D. J. (2009). GAUSSIAN09. Gaussian Inc., Wallingford, CT, USA.]). The differences between calculated and experimental bond lengths and angles are within a few Ångstroms and degrees, respectively, when compared to the experimental parameters, which indicate that our calculations are acceptable (see supplementary Tables 1 and 2). The HOMO–LUMO gap of the mol­ecule is calculated to be about 4.16 eV.

6. Synthesis and crystallization

To a solution of DMAD (dimethyl acetyl­enedi­carboxyl­ate; 0.2 mmol, 2 equiv.) in 10 ml of CHCl3 containing a catalytic amount of DABCO (0.02 mmol, 0.2 equiv.), (3-bromo­benzyl­idene)-4-methyl-5-oxopyrazolidin-2-ium-1-ide (0.10 mmol, 1 equiv.) was added (Fig. 6[link]). The mixture was stirred at 318 K until the consumption of the azomethine imine was complete (monitored by TLC with 3:7 hexa­ne/ethyl acetate v:v). After completion of the reaction, the residue was concentrated in vacuo. The crude product was purified by column chromatography on silica gel using hexa­ne:ethyl acetate (2/8 v:v) as eluent. The title compound was recrystallized from ethanol solution in the form of colourless blocks (yield 68%, m.p. 383 K).

[Figure 6]
Figure 6
Scheme showing the synthesis of the title compound.

7. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 4[link]. Four reflections affected by the beamstop were omitted from the refinement. All H atoms were placed geometrically (C—H = 0.93–0.98 Å) and refined as riding atoms with Uiso(H) = 1.2Ueq(C) or 1.5Ueq(methyl C). The Br atom was modelled as disordered over adjacent sites in a 0.5862:0.4138 ratio.

Table 4
Experimental details

Crystal data
Chemical formula C17H17BrN2O5
Mr 409.23
Crystal system, space group Triclinic, P[\overline{1}]
Temperature (K) 296
a, b, c (Å) 8.8579 (5), 10.5336 (6), 11.0893 (6)
α, β, γ (°) 62.282 (2), 75.437 (2), 88.241 (2)
V3) 882.03 (9)
Z 2
Radiation type Mo Kα
μ (mm−1) 2.36
Crystal size (mm) 0.32 × 0.28 × 0.19
 
Data collection
Diffractometer Bruker D8 VENTURE Super DUO
Absorption correction Multi-scan (SADABS; Krause et al., 2015[Krause, L., Herbst-Irmer, R., Sheldrick, G. M. & Stalke, D. (2015). J. Appl. Cryst. 48, 3-10.])
Tmin, Tmax 0.617, 0.746
No. of measured, independent and observed [I > 2σ(I)] reflections 27467, 3884, 3257
Rint 0.027
(sin θ/λ)max−1) 0.641
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.027, 0.078, 1.04
No. of reflections 3882
No. of parameters 235
H-atom treatment H-atom parameters constrained
Δρmax, Δρmin (e Å−3) 0.23, −0.26
Computer programs: APEX3 and SAINT (Bruker, 2016[Bruker (2016). APEX3, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]), SHELXT2014/5 (Sheldrick, 2015a[Sheldrick, G. M. (2015a). Acta Cryst. A71, 3-8.]), SHELXL2018/3 (Sheldrick, 2015b[Sheldrick, G. M. (2015b). Acta Cryst. C71, 3-8.]), WinGX and ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]), 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.]) and publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Computing details top

Data collection: APEX3 (Bruker, 2016); cell refinement: SAINT (Bruker, 2016); data reduction: SAINT (Bruker, 2016); program(s) used to solve structure: SHELXT2014/5 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2018/3 (Sheldrick, 2015b); molecular graphics: WinGX and ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: Mercury (Macrae et al., 2020) and publCIF (Westrip, 2010).

Dimethyl 3-(3-bromophenyl)-6-methyl-7-oxo-3,5,6,7-tetrahydropyrazolo[1,2-a]pyrazole-1,2-dicarboxylate top
Crystal data top
C17H17BrN2O5Z = 2
Mr = 409.23F(000) = 416
Triclinic, P1Dx = 1.541 Mg m3
a = 8.8579 (5) ÅMo Kα radiation, λ = 0.71073 Å
b = 10.5336 (6) ÅCell parameters from 3884 reflections
c = 11.0893 (6) Åθ = 2.2–27.1°
α = 62.282 (2)°µ = 2.36 mm1
β = 75.437 (2)°T = 296 K
γ = 88.241 (2)°Block, colourless
V = 882.03 (9) Å30.32 × 0.28 × 0.19 mm
Data collection top
Bruker D8 VENTURE Super DUO
diffractometer
3884 independent reflections
Radiation source: INCOATEC IµS micro-focus source3257 reflections with I > 2σ(I)
HELIOS mirror optics monochromatorRint = 0.027
Detector resolution: 10.4167 pixels mm-1θmax = 27.1°, θmin = 2.2°
φ and ω scansh = 1111
Absorption correction: multi-scan
(SADABS; Krause et al., 2015)
k = 1313
Tmin = 0.617, Tmax = 0.746l = 1414
27467 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)] = 0.027Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.078H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.0411P)2 + 0.1854P]
where P = (Fo2 + 2Fc2)/3
3882 reflections(Δ/σ)max < 0.001
235 parametersΔρmax = 0.23 e Å3
0 restraintsΔρmin = 0.26 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)
C10.59723 (18)0.82071 (16)0.63241 (16)0.0400 (3)
C20.73763 (18)0.89402 (17)0.50667 (16)0.0426 (3)
H20.7473290.9973260.4774900.051*
C30.69585 (19)0.8717 (2)0.39196 (17)0.0543 (4)
H3A0.7344730.9556970.3002470.065*
H3B0.7415020.7883890.3879410.065*
C40.8868 (2)0.8311 (3)0.5424 (2)0.0678 (5)
H4A0.9744760.8792670.4610160.102*
H4B0.9021000.8441210.6188050.102*
H4C0.8779910.7300750.5701070.102*
C50.45427 (17)0.73166 (15)0.41577 (15)0.0372 (3)
H50.5330310.6647250.4139000.045*
C60.32540 (17)0.65778 (15)0.55378 (15)0.0377 (3)
C70.35203 (17)0.69677 (15)0.64608 (15)0.0374 (3)
C80.27063 (18)0.64773 (17)0.79956 (16)0.0418 (3)
C90.2384 (3)0.4599 (2)1.03001 (19)0.0738 (6)
H9A0.2708560.3655151.0782060.111*
H9B0.2737640.5217481.0613230.111*
H9C0.1261100.4535181.0505500.111*
C100.21152 (18)0.54235 (16)0.58279 (16)0.0423 (3)
C110.0089 (2)0.3797 (2)0.7483 (2)0.0690 (5)
H11A0.0840120.3617100.8351570.103*
H11B0.0623370.3984300.6772670.103*
H11C0.0477780.2968590.7631030.103*
C120.40315 (17)0.79230 (15)0.28093 (14)0.0367 (3)
C130.4618 (2)0.7461 (2)0.18122 (18)0.0517 (4)
H130.5336040.6777270.1966520.062*
C140.4127 (3)0.8027 (2)0.05800 (19)0.0644 (6)
H140.4536370.7727890.0093990.077*
C150.3053 (2)0.9015 (2)0.03454 (17)0.0610 (5)
H150.2717680.9377160.0473500.073*
C160.2476 (2)0.94653 (18)0.13404 (16)0.0484 (4)
C170.29670 (17)0.89409 (16)0.25580 (15)0.0394 (3)
H170.2581000.9272690.3209790.047*
N10.47794 (14)0.80099 (13)0.58181 (12)0.0385 (3)
N20.52250 (15)0.84889 (13)0.43155 (12)0.0392 (3)
O10.58506 (15)0.78306 (15)0.75542 (12)0.0574 (3)
O20.22293 (17)0.48679 (14)0.50806 (14)0.0631 (4)
O30.09960 (14)0.50348 (13)0.70232 (13)0.0560 (3)
O40.18874 (17)0.72005 (15)0.83908 (14)0.0664 (4)
O50.30539 (15)0.51832 (13)0.87923 (11)0.0537 (3)
Br1A0.08949 (17)1.08438 (13)0.11124 (14)0.05769 (15)0.5862
Br1B0.1173 (3)1.0792 (3)0.0900 (3)0.1081 (10)0.4138
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0449 (8)0.0403 (8)0.0409 (8)0.0084 (6)0.0182 (6)0.0210 (6)
C20.0429 (8)0.0422 (8)0.0438 (8)0.0011 (6)0.0158 (6)0.0188 (7)
C30.0417 (8)0.0765 (12)0.0409 (8)0.0126 (8)0.0039 (7)0.0272 (8)
C40.0453 (10)0.0867 (15)0.0733 (13)0.0103 (9)0.0232 (9)0.0359 (11)
C50.0362 (7)0.0378 (7)0.0373 (7)0.0047 (5)0.0116 (6)0.0168 (6)
C60.0399 (7)0.0346 (7)0.0349 (7)0.0042 (6)0.0137 (6)0.0117 (6)
C70.0356 (7)0.0366 (7)0.0359 (7)0.0069 (5)0.0108 (6)0.0134 (6)
C80.0396 (8)0.0439 (8)0.0382 (8)0.0050 (6)0.0104 (6)0.0167 (7)
C90.0947 (16)0.0698 (13)0.0363 (9)0.0047 (11)0.0136 (9)0.0103 (9)
C100.0438 (8)0.0374 (7)0.0412 (8)0.0031 (6)0.0168 (7)0.0121 (6)
C110.0573 (11)0.0614 (12)0.0733 (13)0.0196 (9)0.0058 (10)0.0241 (10)
C120.0371 (7)0.0409 (7)0.0307 (7)0.0047 (6)0.0057 (6)0.0171 (6)
C130.0526 (10)0.0586 (10)0.0471 (9)0.0028 (8)0.0030 (7)0.0322 (8)
C140.0738 (13)0.0832 (14)0.0400 (9)0.0215 (11)0.0041 (9)0.0400 (10)
C150.0740 (13)0.0699 (12)0.0313 (8)0.0236 (10)0.0151 (8)0.0154 (8)
C160.0523 (9)0.0460 (8)0.0394 (8)0.0105 (7)0.0199 (7)0.0095 (7)
C170.0414 (8)0.0450 (8)0.0320 (7)0.0012 (6)0.0116 (6)0.0173 (6)
N10.0387 (6)0.0437 (7)0.0328 (6)0.0016 (5)0.0103 (5)0.0173 (5)
N20.0428 (7)0.0424 (6)0.0310 (6)0.0011 (5)0.0130 (5)0.0144 (5)
O10.0644 (8)0.0741 (8)0.0392 (6)0.0039 (6)0.0209 (5)0.0274 (6)
O20.0767 (9)0.0566 (7)0.0574 (7)0.0117 (6)0.0126 (6)0.0297 (6)
O30.0482 (7)0.0557 (7)0.0564 (7)0.0121 (5)0.0033 (6)0.0245 (6)
O40.0697 (9)0.0660 (8)0.0554 (7)0.0218 (7)0.0032 (6)0.0297 (7)
O50.0660 (8)0.0486 (6)0.0363 (6)0.0124 (5)0.0126 (5)0.0128 (5)
Br1A0.0563 (3)0.0541 (3)0.0611 (2)0.0139 (2)0.0361 (2)0.0164 (2)
Br1B0.1041 (15)0.0955 (10)0.1272 (17)0.0249 (8)0.0824 (13)0.0302 (9)
Geometric parameters (Å, º) top
C1—O11.2062 (18)C9—H9A0.9600
C1—N11.3765 (19)C9—H9B0.9600
C1—C21.507 (2)C9—H9C0.9600
C2—C41.519 (2)C10—O21.202 (2)
C2—C31.527 (2)C10—O31.329 (2)
C2—H20.9800C11—O31.447 (2)
C3—N21.481 (2)C11—H11A0.9600
C3—H3A0.9700C11—H11B0.9600
C3—H3B0.9700C11—H11C0.9600
C4—H4A0.9600C12—C171.381 (2)
C4—H4B0.9600C12—C131.387 (2)
C4—H4C0.9600C13—C141.392 (3)
C5—N21.4903 (19)C13—H130.9300
C5—C121.5110 (19)C14—C151.367 (3)
C5—C61.523 (2)C14—H140.9300
C5—H50.9800C15—C161.375 (3)
C6—C71.338 (2)C15—H150.9300
C6—C101.466 (2)C16—C171.380 (2)
C7—N11.3801 (19)C16—Br1B1.754 (3)
C7—C81.507 (2)C16—Br1A1.961 (2)
C8—O41.190 (2)C17—H170.9300
C8—O51.3131 (19)N1—N21.4444 (16)
C9—O51.447 (2)
O1—C1—N1124.11 (15)H9A—C9—H9C109.5
O1—C1—C2129.17 (14)H9B—C9—H9C109.5
N1—C1—C2106.72 (12)O2—C10—O3124.51 (15)
C1—C2—C4110.91 (14)O2—C10—C6122.90 (15)
C1—C2—C3103.61 (12)O3—C10—C6112.54 (14)
C4—C2—C3114.19 (15)O3—C11—H11A109.5
C1—C2—H2109.3O3—C11—H11B109.5
C4—C2—H2109.3H11A—C11—H11B109.5
C3—C2—H2109.3O3—C11—H11C109.5
N2—C3—C2106.03 (12)H11A—C11—H11C109.5
N2—C3—H3A110.5H11B—C11—H11C109.5
C2—C3—H3A110.5C17—C12—C13119.18 (14)
N2—C3—H3B110.5C17—C12—C5120.30 (12)
C2—C3—H3B110.5C13—C12—C5120.52 (15)
H3A—C3—H3B108.7C12—C13—C14119.69 (18)
C2—C4—H4A109.5C12—C13—H13120.2
C2—C4—H4B109.5C14—C13—H13120.2
H4A—C4—H4B109.5C15—C14—C13121.00 (16)
C2—C4—H4C109.5C15—C14—H14119.5
H4A—C4—H4C109.5C13—C14—H14119.5
H4B—C4—H4C109.5C14—C15—C16118.90 (16)
N2—C5—C12110.97 (11)C14—C15—H15120.5
N2—C5—C6101.25 (11)C16—C15—H15120.5
C12—C5—C6116.58 (12)C15—C16—C17121.17 (17)
N2—C5—H5109.2C15—C16—Br1B115.19 (16)
C12—C5—H5109.2C17—C16—Br1B123.57 (16)
C6—C5—H5109.2C15—C16—Br1A121.65 (14)
C7—C6—C10127.27 (14)C17—C16—Br1A117.17 (13)
C7—C6—C5109.39 (13)Br1B—C16—Br1A7.44 (12)
C10—C6—C5122.35 (13)C16—C17—C12120.03 (14)
C6—C7—N1110.20 (12)C16—C17—H17120.0
C6—C7—C8131.71 (14)C12—C17—H17120.0
N1—C7—C8118.09 (13)C1—N1—C7130.55 (13)
O4—C8—O5126.49 (15)C1—N1—N2114.06 (11)
O4—C8—C7123.05 (14)C7—N1—N2109.22 (11)
O5—C8—C7110.44 (13)N1—N2—C3103.78 (11)
O5—C9—H9A109.5N1—N2—C5105.01 (10)
O5—C9—H9B109.5C3—N2—C5116.32 (13)
H9A—C9—H9B109.5C10—O3—C11116.75 (14)
O5—C9—H9C109.5C8—O5—C9116.16 (15)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C9—H9A···O1i0.962.423.258 (3)146
C14—H14···O1ii0.932.533.418 (2)161
C11—H11B···O2iii0.962.603.533 (3)164
C3—H3B···O2iv0.972.623.514 (3)154
Symmetry codes: (i) x+1, y+1, z+2; (ii) x, y, z1; (iii) x, y+1, z+1; (iv) x+1, y+1, z+1.
Percentage contributions of interatomic contacts to the Hirshfeld surface of the title compound top
ContactPercentage contribution
H···H37.1
O···H/H···O31.3
Br···H/H···Br13.5
C···H/H···C10.6
N···H/H···N2.1
O···Br/Br···O1.9
C···C1.9
C···N/N···C0.7
O···N/N···O0.3
Br···Br0.3
N···N0.2
Summary of interaction energies (kJ mol–1) calculated for the title compound top
ContactR (Å)EeleEpotEdisErepEtotSymmetry code
C11—H11B···O27.99-15.9-3.6-36.526.5-34.9-x, -y, -z
C3—H3B···O26.38-21.9-6.9-54.438.0-52.1-x, -y, -z
C14—H14···O111.09-9.3-2.6-11.79.8-15.9x, y, z
C9—H9A···O111.96-17.2-4.4-16.621.4-22.6-x, -y, -z
Br1A···O410.81-14.3-4.0-22.415.9-27.7-x, -y, -z
Comparison of the selected experimental and calculated geometric parameters (Å, °) top
Bond lengthsX-rayDFT
O1—C11.206 (2)1.209
C1—N11.377 (2)1.384
N1—N21.444 (2)1.438
N1—C71.380 (2)1.374
C3—N21.481 (2)1.470
C5—N21.490 (2)1.484
C8—O41.190 (2)1.199
C8—O51.313 (2)1.334
C10—O21.202 (2)1.212
C10—O31.329 (2)1.351
O3—C111.447 (2)1.438
O5—C91.447 (2)1.443
C16—Br1A/Br1B1.961 (2)/1.754 (3)1.922
Angles
O1—C1—N1124.1 (2)125.7
O1—C1—C2129.2 (2)129.2
N1—C1—C2106.7 (2)105.1
C1—N1—C7130.6 (2)133.8
C1—N1—N2114.1 (2)113.1
C3—N2—C5116.3 (2)119.8
C7—C8—O4123.1 (2)122.9
C7—C8—O5110.4 (2)110.8
O4—C8—O5126.5 (2)126.3
C6—C10—O2122.9 (2)123.9
C6—C10—O3112.5 (2)112.4
O2—C10—O3124.5 (2)123.6
C10—O3—C11116.8 (2)115.7
C8—O5—C9116.2 (2)115.2
C15—C16—Br1A/Br1B121.7 (2)/115.2 (2)119.2
C17—C16—Br1A/Br1B117.2 (2)/123.6 (2)119.1
Quantum chemical parameters of the title compound calculated by B3LYP/6-311G (d, p) top
ET(eV)101131.745
EHOMO (eV)–6.026
ELUMO (eV)–1.868
DE(LUMO–HOMO) (eV)4.158
Chemical hardness (η)2.079
Chemical Softness (ξ)0.241
Chemical potential (µ)3.947
Electrophilicity (ψ)3.754
Electronegativity (χ)–3.947
Dipole moment (D)3.847
η = 1/2[ELUMO-EHOMO], ξ = 1/2η, µ = [1/2(ELUMO+EHOMO)], ψ = µ2/2η, χ = –µ

Acknowledgements

The authors thank the Faculty of Science, Mohammed V University in Rabat, Morocco, for the X-ray measurements.

References

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