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ISSN: 2056-9890
Volume 75| Part 8| August 2019| Pages 1128-1132
https://doi.org/10.1107/S2056989019009502

Crystal structure of 2-(methyl­amino)­tropone

CROSSMARK_Color_square_no_text.svg
Leandri Jansen van Vuuren,a Hendrik G. Vissera and Marietjie Schutte-Smitha*

aDepartment of Chemistry, PO Box 339, University of the Free State, Bloemfontein, 9301, South Africa
*Correspondence e-mail: SchutteM@ufs.ac.za

Edited by S. Parkin, University of Kentucky, USA (Received 13 June 2019; accepted 2 July 2019; online 9 July 2019)

The title compound, 2-(methyl­amino)­cyclo­hepta-2,4,6-trien-1-one, C8H9NO, crystallizes in the monoclinic space group P21/c, with three independent mol­ecules in the asymmetric unit. The planarity of the mol­ecules is indicated by planes fitted through the seven ring carbon atoms. Small deviations from the planes, with an extremal r.m.s. deviation of 0.0345 Å, are present. In complexes of transition metals with similar ligands, the large planar seven-membered aromatic rings have shown to improve the stability of the complex. Two types of hydrogen-bonding inter­actions, C—H⋯O and N—H⋯O, are observed, as well as bifurcation of these inter­actions. The N—H⋯O inter­actions link mol­ecules to form infinite chains. The packing of mol­ecules in the unit cell shows a pattern of overlapping aromatic rings, forming column-like formations. π–π inter­actions are observed between the overlapping aromatic rings at 3.4462 (19) Å from each other.

CCDC reference: 1937929

Similar articles

1. Chemical context

Tropolone and other troponoids, non-benzenoid compounds, have great pharmacological potential (Guo et al., 2019[Guo, H., Roman, D. & Beemelmanns, C. (2019). Natural Product Reports. https://doi.org/10.1039/C8NP00078F.]). They display a wide range of bioactivities, including anti­microbial (Saleh et al., 1988[Saleh, N. A., Zfiefak, A., Mordarski, M. & Pulverer, G. (1988). Zentralbl. Bakteriol. MikroBiol. Hyg. Med. Microbiol. Infect. Dis. Virol. Paras. 270, 160-170.]), anti­viral (Tavis & Lomonosova, 2015[Tavis, J. E. & Lomonosova, E. (2015). Antiviral Res. 118, 132-138.]) and anti­tumor (Ononye et al., 2013[Ononye, S. N., VanHeyst, M. D., Oblak, E. Z., Zhou, W., Ammar, M., Anderson, A. C. & Wright, D. L. (2013). ACS Med. Chem. Lett. 4, 757-761.]) activities. Many tropolone-related compounds have proved to be possible anti­proliferative agents against a variety of cancer cell lines, including lung, prostate and T-cell malignancies (Liu & Yamauchi, 2006[Liu, S. & Yamauchi, H. (2006). Biochem. Biophys. Res. Commun. 351, 26-32.]; Hsiao et al., 2012[Hsiao, C. J., Hsiao, S. H., Chen, W. L., Guh, J. H., Hsiao, G., Chan, Y. J., Lee, T. H. & Chung, C. L. (2012). Chem. Biol. Interact. 197, 23-30.]). Tropolone has important medical applications in radiopharmacy (Nepveu et al., 1993[Nepveu, F., Jasanada, F. & Walz, L. (1993). Inorg. Chim. Acta, 211, 141-147.]) and as catalyst precursor (Crous et al., 2005[Crous, R., Datt, M., Foster, D., Bennie, L., Steenkamp, C., Huyser, J., Kirsten, L., Steyl, G. & Roodt, A. (2005). Dalton Trans. pp. 1108-1116.]; Roodt et al., 2003[Roodt, A., Otto, S. & Steyl, G. (2003). Coord. Chem. Rev. 245, 121-137.]).

Tropolone and its derivatives are versatile ligands used in inorganic and organometallic chemistry (Roesky, 2000[Roesky, P. W. (2000). Chem. Soc. Rev. 29, 335-345.]; Dias et al., 1995[Dias, H. V. R., Jin, W. & Ratcliff, R. E. (1995). Inorg. Chem. 34, 6100-6105.]; Nozoe et al., 1997[Nozoe, T., Lin, L. C., Hsu, C., Tsay, S., Hakimelahib, G. H. & Hwu, J. R. (1997). J. Chem. Res. (S), pp. 362-363.]; Schutte et al., 2010[Schutte, M., Visser, H. G. & Roodt, A. (2010). Acta Cryst. E66, m859-m860.]; Steyl et al., 2010[Steyl, G., Muller, T. J. & Roodt, A. (2010). Acta Cryst. E66, m1508.]). The carbonyl oxygen and vicinal coordinating substituent, specifically nitro­gen in this study, impart a metal-chelating ability to these types of ligands. The complexes of these ligands with first and second row transition elements have increased over the past few decades. The ligands of importance in this study and future work, namely 2-(alkyl­amino)­tropones and amino­troponimines, are N,O and N,N′ bidentate, monoanionic ligands containing a ten π-electron backbone (Roesky, 2000[Roesky, P. W. (2000). Chem. Soc. Rev. 29, 335-345.]). The π-conjugated backbone is characteristic of these ligands (Nishinaga et al., 2010[Nishinaga, T., Aono, T., Isomura, E., Watanabe, S., Miyake, Y., Miyazaki, A., Enoki, T., Miyasaka, H., Otani, H. & Iyoda, M. (2010). Dalton Trans. 39, 2293-2300.]). Considering the above-mentioned characteristics, tropolone could be considered analogous to the O-donor κ2-O,O′ acetyl­acetonate ligand (acac-O,O′). The tropolone bidentate ligand differs from the acac-O,O′ ligand in a few ways. Of importance to our study is the larger aromatic delocalization, which could afford greater polarizability. Tropolone is also more acidic than the acac-O,O′ ligand. The acidity of the O,N and N,N′ bidentate ligands used in our study and the effect thereof on the chelating ability could be compared to these O,O′ bidentate ligands described in the literature. The ligand–metal–ligand angle, better known as the `bite angle', would also be smaller for a tropolone-derived complex, since it would form a five-membered metallocycle instead of a six-membered one as with acac-O,O′ (Bhalla et al., 2005[Bhalla, G., Oxgaard, J., Goddard, W. & Periana, R. (2005). Organometallics, 24, 3229-3232.]). This could show inter­esting steric and electronic influences at the metal centre and could be further compared to the steric and electronic studies conveyed on β-diketone moieties in similar metal complexes by Manicum et al. (2018[Manicum, A., Schutte-Smith, M. & Visser, H. (2018). Polyhedron, 145, 80-87.]). These ligands, including the title compound, 2-(methyl­amino)­tropone, will form part of the synthesis of water-soluble complexes of rhenium(I) tricarbonyl, gallium(III) and copper(II). Rhenium(I) (Schutte-Smith et al., 2019[Schutte-Smith, M., Roodt, A. & Visser, H. G. (2019). Dalton Trans. https://doi.org/10.1039/C9DT01528K.]), gallium(III) (Green & Welch, 1989[Green, M. & Welch, M. (1989). Int. J. Radiat. Appl. Instrum. B, 16, 435-448.]) and copper(II) (Boschi et al., 2018[Boschi, A., Martini, P., Janevik-Ivanovska, E. & Duatti, A. (2018). Drug Discovery Today, 23, 1489-1501.]) are highly utilized radioisotopes in the radiopharmaceutical industry.

When designing diagnostic or therapeutic radiopharmaceuticals, certain mechanistic aspects are very important, as it is the basis on which some predictions are made regarding the in vivo behaviour. Kinetic studies, utilizing different techniques, are executed to determine the reaction mechanisms by which the proposed radiopharmaceutical complexes will form and react. Results of such studies are important in nuclear medicine as it gives indications regarding the in vivo stability, uptake and excretion as well as the pharmacokinetics of the compounds. Kinetic investigations by Schutte et al. (2011[Schutte, M., Kemp, G., Visser, H. & Roodt, A. (2011). Inorg. Chem. 50, 12486-12498.], 2012[Schutte, M., Roodt, A. & Visser, H. (2012). Inorg. Chem. 51, 11996-12006.]), Schutte-Smith et al. (2019[Schutte-Smith, M., Roodt, A. & Visser, H. G. (2019). Dalton Trans. https://doi.org/10.1039/C9DT01528K.]) and Manicum et al. (2019[Manicum, A., Schutte-Smith, M., Alexander, O., Twigge, L., Roodt, A. & Visser, H. (2019). Inorg. Chem. Commun. 101, 93-98.]) were done on rhenium(I) tricarbonyl tropolonato complexes with satisfying results and conclusions. In the study, methanol substitution was studied using entering nucleophiles in fac-[Re(Trop)(CO)3(MeOH)]. The kinetic study performed at high pressure indicated positive volumes of activation for all of the reactions studied. This was a clear indication towards a dissociative inter­change mechanism.

The application of these ligands in coordination chemistry could be further increased by adding electron donating or withdrawing moieties to the nitro­gen atom.

[Scheme 1]

2. Structural commentary

2-(Methyl­amino)­tropone crystallizes in the monoclinic P21/c space group with three independent mol­ecules, A, B and C, in the asymmetric unit (Fig. 1[link]). The bond distances and angles of the three mol­ecules agree well with each other and with those in similar structures (Barret et al., 2014[Barret, M., Bhatia, P., Kociok-Köhn, G. & Molloy, K. (2014). Transition Met. Chem. 39, 543-551.]; Dwivedi et al., 2016[Dwivedi, A., Binnani, C., Tyagi, D., Rawat, K., Li, P., Zhao, Y., Mobin, S. M., Pathak, B. & Singh, S. K. (2016). Inorg. Chem. 55, 6739-6749.]; Roesky & Bürgstein, 1999[Roesky, P. & Bürgstein, M. (1999). Inorg. Chem. 38, 5629-5632.]; Shimanouchi & Sasada, 1973[Shimanouchi, H. & Sasada, Y. (1973). Acta Cryst. B29, 81-90.]; Siwatch et al., 2011[Siwatch, R. K., Kundu, S., Kumar, S. & Nagendran, S. (2011). Organometallics, 30, 1998-2005.]). The largest differences in bond distances are of the C8B—N1B [1.4470 (18) Å], N1B—C2B [1.3444 (17) Å] and O1B—C1B [1.2561 (15) Å] bonds with the corresponding bonds in 2-(t-butyl­amino)­tropone [1.472 (4) Å; Siwatch et al., 2011[Siwatch, R. K., Kundu, S., Kumar, S. & Nagendran, S. (2011). Organometallics, 30, 1998-2005.]], 2-(iso­propyl­amino)­tropone [1.330 (4) Å; Roesky & Bürgstein, 1999[Roesky, P. & Bürgstein, M. (1999). Inorg. Chem. 38, 5629-5632.]] and 2-(t-butyl­amino)­tropone [1.242 (4) Å; Siwatch et al., 2011[Siwatch, R. K., Kundu, S., Kumar, S. & Nagendran, S. (2011). Organometallics, 30, 1998-2005.]], respectively. Compared to the starting material mol­ecule, tropolone (Shimanouchi & Sasada, 1973[Shimanouchi, H. & Sasada, Y. (1973). Acta Cryst. B29, 81-90.]), the O1B—C1B [1.2561 (15) Å] bond distance is slightly shorter than that of tropolone [1.261 (3) Å], both being in the range of normal C=O bond distance. The C2—N1—C8 bond angle in mol­ecules A [125.69 (13)°], B [125.27 (13)°] and C [125.07 (12)°] are slightly larger than the usual 120° for trigonal-planar bond angles, because of the steric influence of the methyl group. These angles are close to the same angle in 2-(benzyl­amino)­tropone [125.09 (12)°; Barret et al., 2014[Barret, M., Bhatia, P., Kociok-Köhn, G. & Molloy, K. (2014). Transition Met. Chem. 39, 543-551.]]. This could be compared to the large angle in 2-(t-butyl­amino)­tropone [131.9 (2)°; Siwatch et al., 2011[Siwatch, R. K., Kundu, S., Kumar, S. & Nagendran, S. (2011). Organometallics, 30, 1998-2005.]], which deviates even more from 120° due to the highly steric tertiary butyl group. A plane fitted through the seven ring carbon atoms of the three mol­ecules in the asymmetric unit indicates that the mol­ecules are planar. The root-mean-square deviations of mol­ecules A, B and C from the planes are 0.0141 (12), 0.0261 (11) and 0.0345 (11) Å, respectively. The C8—N1—C2—C3 torsion angle, which involves the methyl group, differs for mol­ecule A [−0.8 (2)°], mol­ecule B [2.3 (2)°] and mol­ecule C [7.7 (2)°]. The small deviations from planarity could possibly be ascribed to the inter­molecular hydrogen-bonding inter­actions.

[Figure 1]
Figure 1
The mol­ecular structure of 2-(methyl­amino)­tropone, indicating the numbering scheme, with displacement ellipsoids drawn at the 50% probability level.

3. Supra­molecular features

Nine hydrogen-bonding inter­actions, three C—H⋯O and six N—H⋯O, are observed (Table 1[link] and Fig. 2[link]). Infinite chains are formed along [001]. These supra­molecular chains are formed through N—H⋯O inter­actions linking the mol­ecules together. As in the crystal structure of tropolone (Shimanouchi & Sasada, 1973[Shimanouchi, H. & Sasada, Y. (1973). Acta Cryst. B29, 81-90.]), bifurcation of the hydrogen bonds take place. Bifurcation, also known as the over-coordination of a hydrogen bond, creates both inter- and intra­molecular branches, which might contribute to the stability of the structures. This is an inter­esting phenomenon seen in the orientation of water mol­ecules, where the distribution of acceptor hydrogen bonds, terminating at the lone pairs of the oxygen, is higher (Markovitch & Agmon, 2008[Markovitch, O. & Agmon, N. (2008). Mol. Phys. 106, 485-495.]). This forms over-coordinated oxygens and could also be seen in this crystal structure (Fig. 2[link]). These inter­actions clearly contribute to the array of the mol­ecules in the asymmetric unit (Fig. 2[link]). The mol­ecules show an inter­esting packing format in the unit cell. `Column'-like structures are formed by mol­ecule B packing in a head-to-tail pattern with the aromatic rings overlapping (Fig. 3[link]). A π-inter­action is observed, with a perpendicular distance of 3.4462 (19) Å between the overlapping aromatic rings of two inversion-related B mol­ecules (Fig. 4[link]). These π-inter­actions could not only possibly contribute to the packing format of the mol­ecules in the unit cell, but could also assist in the formation of one-dimensional infinite chains, as Wong et al. (2018[Wong, V., Po, C., Leung, S., Chan, A., Yang, S., Zhu, B., Cui, X. & Yam, V. W. (2018). J. Am. Chem. Soc. 140, 657-666.]) have found in water-soluble platinum (II) salts.

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
N1A—HN1A⋯O1A 0.884 (17) 2.099 (16) 2.5453 (16) 110.3 (13)
N1A—HN1A⋯O1B 0.884 (17) 2.248 (17) 2.9375 (17) 134.6 (14)
N1B—HN1B⋯O1B 0.893 (15) 2.085 (15) 2.5513 (16) 111.5 (12)
N1B—HN1B⋯O1C 0.893 (15) 2.385 (15) 3.1566 (18) 144.7 (13)
N1C—HN1C⋯O1C 0.890 (16) 2.130 (15) 2.5775 (16) 110.3 (12)
N1C—HN1C⋯O1Ai 0.890 (16) 2.313 (16) 2.9759 (17) 131.3 (13)
C5C—H5C⋯O1Bii 0.95 2.42 3.2914 (19) 153
C7B—H7B⋯O1A 0.95 2.42 3.3446 (19) 165
C8C—H8C2⋯O1Ai 0.98 2.56 3.178 (2) 121
Symmetry codes: (i) [x, -y+{\script{3\over 2}}, z-{\script{1\over 2}}]; (ii) x, y-1, z.
[Figure 2]
Figure 2
Hydrogen-bonding inter­actions (Table 1[link]) and infinite chains along [001] in the unit cell.
[Figure 3]
Figure 3
Packing of mol­ecules viewed perpendicular to the ac plane.
[Figure 4]
Figure 4
π–π inter­action (highlighted by the dashed line) between overlapping aromatic rings of mol­ecule B, where B and B* are related through inversion.

4. Database survey

A search of the Cambridge Structural Database (CSD, Version 5.40, update of February 2019; Groom et al., 2016[Groom, C. R., Bruno, I. J., Lightfoot, M. P. & Ward, S. C. (2016). Acta Cryst. B72, 171-179.]) using a C7H5ONH fragment yielded four hits of 2-(alkyl­amino)­tropones. These include 2-(iso­propyl­amino)­tropone (LIGVOM: Roesky & Bürgstein, 1999[Roesky, P. & Bürgstein, M. (1999). Inorg. Chem. 38, 5629-5632.]), 2-(benzyl­amino)­tropone (NOPRUH: Barret et al., 2014[Barret, M., Bhatia, P., Kociok-Köhn, G. & Molloy, K. (2014). Transition Met. Chem. 39, 543-551.]), 2-(t-butyl­amino)­tropone (OZINUH: Siwatch et al., 2011[Siwatch, R. K., Kundu, S., Kumar, S. & Nagendran, S. (2011). Organometallics, 30, 1998-2005.]) and 2-(cyclohexyl­amino)­tropone (OTIMUB: Dwivedi et al., 2016[Dwivedi, A., Binnani, C., Tyagi, D., Rawat, K., Li, P., Zhao, Y., Mobin, S. M., Pathak, B. & Singh, S. K. (2016). Inorg. Chem. 55, 6739-6749.]). Of the four structures, only the 2-(iso­propyl­amino)­tropone and the 2-(benzyl­amino)­tropone crystallize in the P21/c space group.

5. Synthesis and crystallization

Tropolone (505 mg, 4.132 mmol) was dissolved in 20 mL of a 40% methyl­amine solution. The reaction mixture was stirred at room temperature for 7 d. The product was extracted three times with 30 mL of chloro­form, and the organic layer was washed with 50 mL of water. The organic layer was dried with Na2SO4 and the solvent removed under reduced pressure. A 46.03% yield (257.1 mg, 1.902 mmol) was obtained. Crystals suitable for single crystal X-ray diffraction data collection were obtained by recrystallization from hexane with slow evaporation. Yield: 0.2571 g, 46.03%. IR (cm−1): νNH = 3304, νCO = 1597. UV/Vis: λmax = 269 nm (∊ = 1.1885 × 105 Lmol−1cm−1). 1H NMR (300 MHz, CDCl3): δ = 7.201 (m, 4H), 6.682 (t, 1H, J = 9.6 Hz), 6.501 (d, 1H, J = 10.5 Hz), 3.056 (d, 3H, J = 5.4 Hz). 13C NMR (300MHz, CDCl3): δ = 177, 157, 137, 136, 129, 122, 108, 29.

6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2[link]. Methyl and aromatic hydrogen atoms were placed in geometrically idealized positions (C—H = 0.95–0.98 Å) and constrained to ride on their parent atoms [Uiso(H) = 1.5Ueq(C) and 1.2Ueq(C)], while N—H hydrogens were freely refined.

Table 2
Experimental details

Crystal data
Chemical formula C8H9NO
Mr 135.16
Crystal system, space group Monoclinic, P21/c
Temperature (K) 100
a, b, c (Å) 17.635 (5), 7.817 (2), 16.718 (4)
β (°) 110.639 (9)
V (Å3) 2156.8 (10)
Z 12
Radiation type Mo Kα
μ (mm−1) 0.08
Crystal size (mm) 0.58 × 0.30 × 0.28
 
Data collection
Diffractometer Bruker X8 APEXII 4K Kappa CCD
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 0.970, 0.977
No. of measured, independent and observed [I > 2σ(I)] reflections 33879, 5192, 3575
Rint 0.046
(sin θ/λ)max (Å−1) 0.660
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.039, 0.104, 1.03
No. of reflections 5192
No. of parameters 287
H-atom treatment H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3) 0.17, −0.13
Computer programs: APEX2 and SAINT-Plus (Bruker, 2012[Bruker (2012). APEX2, SAINT, Bruker AXS Inc, Madison, Wisconsin, USA.]), SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]), SHELXL2018 (Sheldrick, 2015[Sheldrick, G. M. (2015). Acta Cryst. C71, 3-8.]), DIAMOND (Brandenburg, 2006[Brandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.]) and WinGX (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]).

Supporting information

CCDC reference: 1937929

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S2056989019009502/pk2619sup1.cif

Supporting information file. DOI: https://doi.org/10.1107/S2056989019009502/pk2619Isup2.cml

checkCIF report


Computing details top

Data collection: APEX2 (Bruker, 2012); cell refinement: SAINT-Plus (Bruker, 2012); data reduction: SAINT-Plus (Bruker, 2012); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2018 (Sheldrick, 2015); molecular graphics: DIAMOND (Brandenburg, 2006); software used to prepare material for publication: WinGX (Farrugia, 2012).

2-(Methylamino)cyclohepta-2,4,6-trien-1-one top
Crystal data top
C8H9NOF(000) = 864
Mr = 135.16Dx = 1.249 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 6617 reflections
a = 17.635 (5) Åθ = 3.5–23.7°
b = 7.817 (2) ŵ = 0.08 mm−1
c = 16.718 (4) ÅT = 100 K
β = 110.639 (9)°Cuboid, yellow
V = 2156.8 (10) Å30.58 × 0.30 × 0.28 mm
Z = 12
Data collection top
Bruker X8 APEXII 4K Kappa CCD
diffractometer		5192 independent reflections
Radiation source: fine-focus sealed tube3575 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.046
ω scansθmax = 28.0°, θmin = 3.7°
Absorption correction: multi-scan
SADABS (Krause et al., 2015)		h = −23→23
Tmin = 0.970, Tmax = 0.977k = −10→10
33879 measured reflectionsl = −20→22
Refinement top
Refinement on F2Secondary atom site location: structure-invariant direct methods
Least-squares matrix: fullHydrogen site location: mixed
R[F2 > 2σ(F2)] = 0.039H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.104 w = 1/[σ2(Fo2) + (0.0361P)2 + 0.437P]
where P = (Fo2 + 2Fc2)/3
S = 1.03(Δ/σ)max < 0.001
5192 reflectionsΔρmax = 0.17 e Å−3
287 parametersΔρmin = −0.13 e Å−3
0 restraintsExtinction correction: SHELXL2018 (Sheldrick, 2015)
0 constraintsExtinction coefficient: 0.0113 (9)
Primary atom site location: structure-invariant direct methods
Special details top

Experimental. The intensity data was collected on a Bruker X8 ApexII 4K Kappa CCD diffractometer using an exposure time of 10 seconds/frame. A total of 1436 frames was collected with a frame width of 0.5° covering up to θ = 27.99° with 99.7% completeness accomplished.

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*/Ueq
C8A0.12323 (10)0.5412 (2)0.21119 (10)0.0626 (4)
H8A10.1136020.4212390.2217020.094*
H8A20.1725710.5498450.1971690.094*
H8A30.0770510.5849320.1633590.094*
C8B0.49672 (10)0.4930 (2)0.26816 (10)0.0586 (4)
H8B10.5307290.5887910.2633640.088*
H8B20.470580.4408520.21180.088*
H8B30.5304110.4075380.3077470.088*
C8C0.19718 (11)0.2656 (2)−0.10383 (9)0.0588 (4)
H8C10.2346720.189118−0.1179540.088*
H8C20.1870040.367098−0.1405130.088*
H8C30.1459750.20569−0.1130270.088*
N1A0.13282 (7)0.64142 (16)0.28726 (8)0.0460 (3)
N1B0.43536 (8)0.55487 (16)0.29999 (8)0.0454 (3)
N1C0.23250 (7)0.31715 (16)−0.01509 (7)0.0450 (3)
O1A0.17457 (6)0.83578 (13)0.41777 (6)0.0530 (3)
O1B0.30974 (5)0.61826 (14)0.33715 (6)0.0515 (3)
O1C0.28810 (7)0.46038 (12)0.13314 (6)0.0574 (3)
HN1A0.1803 (10)0.689 (2)0.3149 (10)0.064 (5)*
HN1B0.3829 (9)0.5397 (19)0.2695 (10)0.052 (4)*
HN1C0.2345 (9)0.428 (2)−0.0016 (10)0.056 (5)*
C1B0.37461 (8)0.67009 (17)0.39220 (8)0.0379 (3)
C2B0.44995 (7)0.63079 (16)0.37612 (8)0.0379 (3)
C3B0.52868 (8)0.66224 (19)0.43132 (9)0.0476 (3)
H3B0.5697820.6257120.4106630.057*
C4B0.55733 (9)0.7385 (2)0.51194 (10)0.0545 (4)
H4B0.6146660.740950.5382030.065*
C5B0.51628 (9)0.8101 (2)0.55919 (10)0.0553 (4)
H5B0.5480860.8553010.6134040.066*
C6B0.43262 (9)0.82372 (19)0.53599 (9)0.0510 (4)
H6B0.4144950.8828380.5755650.061*
C7B0.37249 (8)0.76418 (18)0.46432 (8)0.0437 (3)
H7B0.3193140.7907610.4624240.052*
C1C0.27959 (8)0.30140 (16)0.13520 (8)0.0396 (3)
C2C0.25275 (7)0.21032 (16)0.05204 (8)0.0346 (3)
C3C0.24942 (8)0.03409 (16)0.03938 (9)0.0406 (3)
H3C0.236584−0.000441−0.0183810.049*
C4C0.26179 (8)−0.09981 (17)0.09743 (9)0.0460 (3)
H4C0.257336−0.2109330.0731890.055*
C5C0.27941 (9)−0.09661 (19)0.18414 (10)0.0495 (4)
H5C0.283417−0.2040590.2118790.059*
C6C0.29204 (8)0.0487 (2)0.23568 (9)0.0491 (4)
H6C0.3016510.0266550.2943220.059*
C7C0.29278 (8)0.21802 (19)0.21506 (9)0.0458 (3)
H7C0.3040730.2936720.2623110.055*
C1A0.10733 (8)0.76484 (17)0.40289 (8)0.0411 (3)
C2A0.07897 (8)0.65224 (16)0.32681 (8)0.0395 (3)
C3A0.00556 (8)0.56527 (19)0.29566 (10)0.0538 (4)
H3A−0.0035640.5057680.2435420.065*
C4A−0.05654 (9)0.5510 (2)0.32809 (13)0.0647 (5)
H4A−0.1005880.480990.2954090.078*
C5A−0.06451 (10)0.6213 (2)0.39924 (13)0.0702 (5)
H5A−0.1120640.592340.4105950.084*
C6A−0.01009 (11)0.7312 (3)0.45709 (12)0.0707 (5)
H6A−0.0260390.7684860.5029060.085*
C7A0.06298 (10)0.7941 (2)0.45827 (10)0.0584 (4)
H7A0.0884610.8706060.5040390.07*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C8A0.0635 (10)0.0735 (11)0.0479 (9)−0.0028 (9)0.0162 (8)−0.0172 (8)
C8B0.0646 (10)0.0627 (10)0.0585 (10)0.0095 (8)0.0343 (8)0.0034 (8)
C8C0.0758 (11)0.0571 (9)0.0380 (8)0.0003 (8)0.0132 (7)0.0016 (7)
N1A0.0412 (7)0.0501 (7)0.0437 (7)−0.0052 (6)0.0114 (5)−0.0085 (6)
N1B0.0432 (7)0.0527 (7)0.0421 (7)0.0019 (6)0.0171 (6)0.0013 (5)
N1C0.0587 (7)0.0373 (6)0.0384 (6)−0.0010 (5)0.0164 (5)−0.0014 (5)
O1A0.0484 (6)0.0480 (6)0.0582 (6)−0.0073 (5)0.0132 (5)−0.0137 (5)
O1B0.0353 (5)0.0712 (7)0.0441 (6)−0.0060 (5)0.0091 (4)−0.0063 (5)
O1C0.0861 (8)0.0361 (5)0.0494 (6)−0.0083 (5)0.0230 (6)−0.0073 (5)
C1B0.0360 (7)0.0408 (7)0.0354 (7)−0.0023 (5)0.0106 (5)0.0074 (5)
C2B0.0385 (7)0.0371 (7)0.0388 (7)−0.0007 (5)0.0146 (6)0.0094 (6)
C3B0.0355 (7)0.0566 (9)0.0517 (8)0.0001 (6)0.0166 (6)0.0091 (7)
C4B0.0353 (7)0.0669 (10)0.0522 (9)−0.0082 (7)0.0042 (6)0.0085 (8)
C5B0.0516 (9)0.0634 (10)0.0422 (8)−0.0135 (7)0.0056 (7)−0.0022 (7)
C6B0.0576 (9)0.0530 (9)0.0425 (8)−0.0058 (7)0.0177 (7)−0.0046 (7)
C7B0.0409 (7)0.0497 (8)0.0417 (7)−0.0007 (6)0.0158 (6)0.0021 (6)
C1C0.0402 (7)0.0381 (7)0.0416 (7)−0.0022 (5)0.0158 (6)−0.0058 (6)
C2C0.0327 (6)0.0361 (6)0.0365 (7)0.0003 (5)0.0141 (5)−0.0009 (5)
C3C0.0445 (7)0.0367 (7)0.0417 (7)−0.0003 (6)0.0164 (6)−0.0054 (6)
C4C0.0478 (8)0.0337 (7)0.0571 (9)0.0026 (6)0.0192 (7)−0.0010 (6)
C5C0.0486 (8)0.0423 (8)0.0561 (9)0.0042 (6)0.0165 (7)0.0120 (7)
C6C0.0462 (8)0.0590 (9)0.0393 (8)−0.0020 (7)0.0117 (6)0.0074 (7)
C7C0.0492 (8)0.0502 (8)0.0372 (7)−0.0054 (6)0.0143 (6)−0.0050 (6)
C1A0.0396 (7)0.0367 (7)0.0420 (7)0.0057 (6)0.0080 (6)0.0033 (6)
C2A0.0368 (7)0.0347 (7)0.0417 (7)0.0039 (5)0.0072 (6)0.0032 (6)
C3A0.0406 (8)0.0510 (8)0.0620 (10)−0.0038 (6)0.0086 (7)−0.0062 (7)
C4A0.0392 (8)0.0596 (10)0.0907 (13)−0.0038 (7)0.0170 (8)0.0064 (9)
C5A0.0445 (9)0.0794 (12)0.0920 (14)0.0088 (9)0.0308 (9)0.0247 (11)
C6A0.0661 (11)0.0884 (13)0.0683 (11)0.0241 (10)0.0372 (10)0.0169 (10)
C7A0.0603 (10)0.0643 (10)0.0504 (9)0.0113 (8)0.0194 (8)−0.0021 (8)
Geometric parameters (Å, º) top
C8A—N1A1.4518 (19)C4B—H4B0.95
C8A—H8A10.98C5B—C6B1.391 (2)
C8A—H8A20.98C5B—H5B0.95
C8A—H8A30.98C6B—C7B1.3716 (19)
C8B—N1B1.4470 (18)C6B—H6B0.95
C8B—H8B10.98C7B—H7B0.95
C8B—H8B20.98C1C—C7C1.4293 (19)
C8B—H8B30.98C1C—C2C1.4832 (18)
C8C—N1C1.4492 (18)C2C—C3C1.3919 (18)
C8C—H8C10.98C3C—C4C1.3913 (19)
C8C—H8C20.98C3C—H3C0.95
C8C—H8C30.98C4C—C5C1.372 (2)
N1A—C2A1.3376 (18)C4C—H4C0.95
N1A—HN1A0.884 (17)C5C—C6C1.395 (2)
N1B—C2B1.3444 (17)C5C—H5C0.95
N1B—HN1B0.893 (15)C6C—C7C1.369 (2)
N1C—C2C1.3423 (16)C6C—H6C0.95
N1C—HN1C0.890 (16)C7C—H7C0.95
O1A—O1A0.000 (3)C1A—C7A1.426 (2)
O1A—C1A1.2519 (16)C1A—C2A1.4812 (19)
O1B—O1B0.0000 (19)C2A—C3A1.3906 (19)
O1B—C1B1.2561 (15)C3A—C4A1.387 (2)
O1C—O1C0.000 (3)C3A—H3A0.95
O1C—C1C1.2537 (16)C4A—C5A1.362 (3)
C1B—C7B1.4240 (19)C4A—H4A0.95
C1B—C2B1.4777 (18)C5A—C6A1.393 (3)
C2B—C3B1.3917 (19)C5A—H5A0.95
C3B—C4B1.395 (2)C6A—C7A1.373 (2)
C3B—H3B0.95C6A—H6A0.95
C4B—C5B1.366 (2)C7A—H7A0.95
N1A—C8A—H8A1109.5C6B—C7B—C1B132.22 (14)
N1A—C8A—H8A2109.5C6B—C7B—H7B113.9
H8A1—C8A—H8A2109.5C1B—C7B—H7B113.9
N1A—C8A—H8A3109.5O1C—C1C—O1C0.00 (10)
H8A1—C8A—H8A3109.5O1C—C1C—C7C119.73 (12)
H8A2—C8A—H8A3109.5O1C—C1C—C7C119.73 (12)
N1B—C8B—H8B1109.5O1C—C1C—C2C116.86 (12)
N1B—C8B—H8B2109.5O1C—C1C—C2C116.86 (12)
H8B1—C8B—H8B2109.5C7C—C1C—C2C123.36 (12)
N1B—C8B—H8B3109.5N1C—C2C—C3C120.28 (12)
H8B1—C8B—H8B3109.5N1C—C2C—C1C112.83 (11)
H8B2—C8B—H8B3109.5C3C—C2C—C1C126.87 (12)
N1C—C8C—H8C1109.5C4C—C3C—C2C130.60 (13)
N1C—C8C—H8C2109.5C4C—C3C—H3C114.7
H8C1—C8C—H8C2109.5C2C—C3C—H3C114.7
N1C—C8C—H8C3109.5C5C—C4C—C3C130.16 (13)
H8C1—C8C—H8C3109.5C5C—C4C—H4C114.9
H8C2—C8C—H8C3109.5C3C—C4C—H4C114.9
C2A—N1A—C8A125.69 (13)C4C—C5C—C6C126.51 (13)
C2A—N1A—HN1A115.0 (11)C4C—C5C—H5C116.7
C8A—N1A—HN1A118.8 (11)C6C—C5C—H5C116.7
C2B—N1B—C8B125.27 (13)C7C—C6C—C5C130.18 (14)
C2B—N1B—HN1B114.4 (10)C7C—C6C—H6C114.9
C8B—N1B—HN1B120.3 (10)C5C—C6C—H6C114.9
C2C—N1C—C8C125.07 (12)C6C—C7C—C1C131.55 (13)
C2C—N1C—HN1C114.7 (10)C6C—C7C—H7C114.2
C8C—N1C—HN1C119.5 (10)C1C—C7C—H7C114.2
O1A—O1A—C1A0 (10)O1A—C1A—O1A0.00 (9)
O1B—O1B—C1B0 (10)O1A—C1A—C7A119.86 (13)
O1C—O1C—C1C0 (10)O1A—C1A—C7A119.86 (13)
O1B—C1B—O1B0.00 (15)O1A—C1A—C2A116.32 (12)
O1B—C1B—C7B119.87 (12)O1A—C1A—C2A116.32 (12)
O1B—C1B—C7B119.87 (12)C7A—C1A—C2A123.82 (13)
O1B—C1B—C2B116.40 (12)N1A—C2A—C3A120.88 (13)
O1B—C1B—C2B116.40 (12)N1A—C2A—C1A112.23 (11)
C7B—C1B—C2B123.72 (12)C3A—C2A—C1A126.88 (13)
N1B—C2B—C3B121.26 (12)C4A—C3A—C2A130.67 (16)
N1B—C2B—C1B112.32 (11)C4A—C3A—H3A114.7
C3B—C2B—C1B126.40 (13)C2A—C3A—H3A114.7
C2B—C3B—C4B130.76 (14)C5A—C4A—C3A130.39 (16)
C2B—C3B—H3B114.6C5A—C4A—H4A114.8
C4B—C3B—H3B114.6C3A—C4A—H4A114.8
C5B—C4B—C3B130.44 (14)C4A—C5A—C6A126.67 (16)
C5B—C4B—H4B114.8C4A—C5A—H5A116.7
C3B—C4B—H4B114.8C6A—C5A—H5A116.7
C4B—C5B—C6B126.62 (14)C7A—C6A—C5A130.12 (17)
C4B—C5B—H5B116.7C7A—C6A—H6A114.9
C6B—C5B—H5B116.7C5A—C6A—H6A114.9
C7B—C6B—C5B129.43 (15)C6A—C7A—C1A131.32 (16)
C7B—C6B—H6B115.3C6A—C7A—H7A114.3
C5B—C6B—H6B115.3C1A—C7A—H7A114.3
O1B—O1B—C1B—C7B0.00 (7)N1C—C2C—C3C—C4C−174.98 (13)
O1B—O1B—C1B—C2B0.00 (11)C1C—C2C—C3C—C4C7.0 (2)
C8B—N1B—C2B—C3B2.3 (2)C2C—C3C—C4C—C5C1.4 (3)
C8B—N1B—C2B—C1B−176.57 (13)C3C—C4C—C5C—C6C−2.5 (3)
O1B—C1B—C2B—N1B4.66 (16)C4C—C5C—C6C—C7C−2.3 (3)
O1B—C1B—C2B—N1B4.66 (16)C5C—C6C—C7C—C1C1.4 (3)
C7B—C1B—C2B—N1B−174.08 (12)O1C—C1C—C7C—C6C−175.92 (15)
O1B—C1B—C2B—C3B−174.13 (13)O1C—C1C—C7C—C6C−175.92 (15)
O1B—C1B—C2B—C3B−174.13 (13)C2C—C1C—C7C—C6C6.6 (2)
C7B—C1B—C2B—C3B7.1 (2)O1A—O1A—C1A—C7A0.00 (3)
N1B—C2B—C3B—C4B179.84 (15)O1A—O1A—C1A—C2A0.00 (2)
C1B—C2B—C3B—C4B−1.5 (2)C8A—N1A—C2A—C3A−0.8 (2)
C2B—C3B—C4B—C5B−2.6 (3)C8A—N1A—C2A—C1A179.80 (13)
C3B—C4B—C5B—C6B−0.1 (3)O1A—C1A—C2A—N1A1.88 (17)
C4B—C5B—C6B—C7B3.1 (3)O1A—C1A—C2A—N1A1.88 (17)
C5B—C6B—C7B—C1B0.8 (3)C7A—C1A—C2A—N1A−177.78 (13)
O1B—C1B—C7B—C6B174.25 (15)O1A—C1A—C2A—C3A−177.44 (13)
O1B—C1B—C7B—C6B174.25 (15)O1A—C1A—C2A—C3A−177.44 (13)
C2B—C1B—C7B—C6B−7.1 (2)C7A—C1A—C2A—C3A2.9 (2)
O1C—O1C—C1C—C7C0.0 (2)N1A—C2A—C3A—C4A176.30 (16)
O1C—O1C—C1C—C2C0.0 (2)C1A—C2A—C3A—C4A−4.4 (3)
C8C—N1C—C2C—C3C7.7 (2)C2A—C3A—C4A—C5A1.6 (3)
C8C—N1C—C2C—C1C−174.00 (13)C3A—C4A—C5A—C6A1.5 (3)
O1C—C1C—C2C—N1C−7.16 (17)C4A—C5A—C6A—C7A−0.6 (3)
O1C—C1C—C2C—N1C−7.16 (17)C5A—C6A—C7A—C1A−1.8 (3)
C7C—C1C—C2C—N1C170.43 (12)O1A—C1A—C7A—C6A−178.88 (16)
O1C—C1C—C2C—C3C171.01 (13)O1A—C1A—C7A—C6A−178.88 (16)
O1C—C1C—C2C—C3C171.01 (13)C2A—C1A—C7A—C6A0.8 (3)
C7C—C1C—C2C—C3C−11.4 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1A—HN1A···O1A0.884 (17)2.099 (16)2.5453 (16)110.3 (13)
N1A—HN1A···O1B0.884 (17)2.248 (17)2.9375 (17)134.6 (14)
N1B—HN1B···O1B0.893 (15)2.085 (15)2.5513 (16)111.5 (12)
N1B—HN1B···O1C0.893 (15)2.385 (15)3.1566 (18)144.7 (13)
N1C—HN1C···O1C0.890 (16)2.130 (15)2.5775 (16)110.3 (12)
N1C—HN1C···O1Ai0.890 (16)2.313 (16)2.9759 (17)131.3 (13)
C5C—H5C···O1Bii0.952.423.2914 (19)153
C7B—H7B···O1A0.952.423.3446 (19)165
C8C—H8C2···O1Ai0.982.563.178 (2)121
Symmetry codes: (i) x, −y+3/2, z−1/2; (ii) x, y−1, z.
 

Acknowledgements

This work is based on the research supported in part by the National Research Foundation of South Africa. We would also like to thank the University of the Free State.

References

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ISSN: 2056-9890
Volume 75| Part 8| August 2019| Pages 1128-1132
https://doi.org/10.1107/S2056989019009502
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