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ISSN: 2056-9890

3-(4-Nitro­benz­yl)-4H-chromen-4-one

aSchool of Chemistry and Physics, University of KwaZulu-Natal, Durban 4000, South Africa, bSchool of Chemical Engineering, University of KwaZulu-Natal, Durban, South Africa, and cChemistry Department, University of Cape Town, Rondebosch 7701, South Africa
*Correspondence e-mail: koorbanally@ukzn.ac.za

(Received 20 February 2013; accepted 4 March 2013; online 9 March 2013)

In the title compound, C16H11NO4, the dihedral angle between the ten-membered chromen-4-one ring system (r.m.s. deviation = 0.0095 Å) and the benzene ring is 86.16 (5)°. In the crystal, mol­ecules are linked into a three-dimensional network by weak C—H⋯O hydrogen bonds. The crystal studied was a non-merohedral twin, with the minor twin component refining to 0.093 (1).

Related literature

For the preparation, see: Desideri et al. (2011[Desideri, N., Bolasco, A., Fioravanti, R., Proietti Monaco, L., Orallo, F., Yáñez, M., Ortuso, F. & Alcaro, S. (2011). J. Med. Chem. 54, 2155-2164.]); Valkonen et al. (2012[Valkonen, A., Laihia, K., Kolehmainen, E., Kauppinen, R. & Perjési, P. (2012). Struct. Chem. 23, 209-217.]). For related structures, see: Valkonen et al. (2012[Valkonen, A., Laihia, K., Kolehmainen, E., Kauppinen, R. & Perjési, P. (2012). Struct. Chem. 23, 209-217.]); Gopaul et al. (2013[Gopaul, K., Koorbanally, N. A., Shaikh, M., Su, H. & Ramjugernath, D. (2013). Acta Cryst. E69, o364.]). For the biological activity of homoisoflavonoids, see: Abegaz et al. (2007[Abegaz, B. M., Mutanyatta-Comar, J. & Nindi, M. (2007). Nat. Prod. Commun. 2, 475-498.]).

[Scheme 1]

Experimental

Crystal data
  • C16H11NO4

  • Mr = 281.26

  • Monoclinic, P 21 /n

  • a = 4.9246 (9) Å

  • b = 10.0160 (19) Å

  • c = 25.907 (5) Å

  • β = 92.845 (4)°

  • V = 1276.3 (4) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.11 mm−1

  • T = 173 K

  • 0.35 × 0.09 × 0.08 mm

Data collection
  • Bruker Kappa DUO APEXII diffractometer

  • Absorption correction: multi-scan (TWINABS; Sheldrick, 1997[Sheldrick, G. M. (1997). TWINABS. University of Göttingen, Germany.]) Tmin = 0.964, Tmax = 0.992

  • 87638 measured reflections

  • 3303 independent reflections

  • 2887 reflections with I > 2σ(I)

  • Rint = 0.063

Refinement
  • R[F2 > 2σ(F2)] = 0.050

  • wR(F2) = 0.154

  • S = 1.09

  • 3303 reflections

  • 191 parameters

  • H-atom parameters constrained

  • Δρmax = 0.25 e Å−3

  • Δρmin = −0.23 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C2—H2⋯O2i 0.95 2.38 3.322 (3) 170
C7—H7⋯O3ii 0.95 2.56 3.491 (3) 166
C9—H9⋯O4iii 0.95 2.42 3.355 (3) 167
C13—H13⋯O3iv 0.95 2.53 3.382 (3) 149
C16—H16⋯O2v 0.95 2.46 3.378 (3) 163
Symmetry codes: (i) [-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (ii) [x-{\script{1\over 2}}, -y+{\script{3\over 2}}, z-{\script{1\over 2}}]; (iii) [-x+{\script{5\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (iv) -x+1, -y+1, -z+1; (v) x+1, y, z.

Data collection: APEX2 (Bruker, 2006[Bruker (2006). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2006[Bruker (2006). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

Homoisoflavonoids are a group of naturally occurring oxygen heterocyclic compounds, related to the flavonoids, which consists of a chromone skeleton with a benzyl or benzylidene group at C-3. In the 3-benzyl-4-chromonanone class of homoisoflavonoid, an extra methylene group exists between the phenyl group and the chromone skeleton. They are commonly synthesized by either the acid or base catalysed condensation of an aromatic aldehyde with chromanone (Desideri et al., 2011, Valkonen et al., 2012). Naturally occurring homoisoflavonoids are normally oxygenated and have shown a wide range of biological activities (Abegaz et al., 2007).

The molecular structure of the title compound is shown in Fig. 1. The dihedral angle between the 10-membered co-planar chromone ring and the nitrated phenyl ring is 86.16 (5)°. In the crystal, the inter-moclecular weak hydrogen bonds C—H···O link the molecules into a three dimentional network, as shown in Fig.2. The details of the hydrogen bonds are shown in Table 1.

Related literature top

For the preparation, see: Desideri et al. (2011); Valkonen et al. (2012). For related structures, see: Valkonen et al. (2012); Gopaul et al. (2013). For the biological activity of homoisoflavonoids, see: Abegaz et al. (2007).

Experimental top

A mixture of chroman-4-one (1.02 g, 6.749 mmol), 4-nitrobenzaldehyde (1.22 g, 8.099 mmol) and 10–15 drops of piperidine was heated at 80°C for 12 hrs. The reaction mixture was monitored for completion by thin layer chromatography. Upon completion, the reaction mixture was cooled, diluted with water and neutralized using 10% HCl. To the viscous reaction mixture, 20 ml of ethyl acetate was added. Upon the addition of hexane to the reaction mixture, the homoisoflavonoid precipitated out. The powdered product was filtered, washed with hexane and dried under vacuum. Upon slow evaporation of chloroform, the crystals of the homoisoflavonoid were obtained. (m.p. of 179–180 °C).

1H NMR (400 MHz, CDCl3) δ: 3.87 (2H, s, H-9), 7.38 (1H, t, J=7.54 Hz, H-6), 7.41 (1H, d, J=8.60 Hz, H-8), 7.45 (1H, d, J=8.48 Hz, H-2'/6'), 7.65 (1H, td, J=8.32, 1.10 Hz, H-7), 7.79 (1H, s, H-2), 8.12 (1H, d, J=8.56 Hz, H-3'/5'), 8.18 (1H, dd, J=7.98, 0.66 Hz, H-5).

13C NMR (100 MHz, CDCl3) δ: 31.89 (C-9), 118.15 (C-8), 123.06 (C-3/1'), 123.79 (C-3'/5'), 123.83 (C-4a), 125.32 (C-6), 125.92 (C-5), 129.65 (C-2'/6'), 133.84 (C-7), 146.76 (C-4'), 153.14 (C-2), 156.52 (C-8a), 177.18 (C-4).

Refinement top

The crystal was a non-merohedral twin. Two domains were indexed using CELL_NOW1 and the intensity data for each domain was then integrated, reduced using the program SAINT. The combined data were scaled and absorption correction performed using TWINABS. The structure was solved by direct methods using SHELXS97 and refined by full-matrix least-squares methods based on F2 using SHELXL97. All non-hydrogen atoms were refined anisotropically. All hydrogen atoms were placed in idealized positions and refined with geometrical constraints. The structure was refined to R factor = 0.0504, BASF = 0.093 (1) for HKLF5.

Computing details top

Data collection: APEX2 (Bruker, 2006); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. : A view of the molecule with displacement ellipsoids drawn at the 50% probability level and H atoms drawn as circles of arbitary size.
[Figure 2] Fig. 2. : Projection viewed along the a axis, showing the inter-molecular C—H···O hydrogen bonding network. The H-bond involving H atoms on the molecule of the asymmetric unit were marked for identification. The other H atoms were omitted for clarity. The H-bonds are shown as dotted lines.
3-(4-Nitrobenzyl)-4H-chromen-4-one top
Crystal data top
C16H11NO4F(000) = 584
Mr = 281.26Dx = 1.464 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 3303 reflections
a = 4.9246 (9) Åθ = 1.6–27.4°
b = 10.0160 (19) ŵ = 0.11 mm1
c = 25.907 (5) ÅT = 173 K
β = 92.845 (4)°Needle, colourless
V = 1276.3 (4) Å30.35 × 0.09 × 0.08 mm
Z = 4
Data collection top
Bruker Kappa DUO APEXII
diffractometer
3303 independent reflections
Radiation source: fine-focus sealed tube2887 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.063
0.5° ϕ scans and ω scansθmax = 27.4°, θmin = 1.6°
Absorption correction: multi-scan
(TWINABS; Sheldrick, 1997)
h = 66
Tmin = 0.964, Tmax = 0.992k = 012
87638 measured reflectionsl = 033
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)] = 0.050Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.154H-atom parameters constrained
S = 1.09 w = 1/[σ2(Fo2) + (0.0779P)2 + 0.7278P]
where P = (Fo2 + 2Fc2)/3
3303 reflections(Δ/σ)max < 0.001
191 parametersΔρmax = 0.25 e Å3
0 restraintsΔρmin = 0.23 e Å3
Crystal data top
C16H11NO4V = 1276.3 (4) Å3
Mr = 281.26Z = 4
Monoclinic, P21/nMo Kα radiation
a = 4.9246 (9) ŵ = 0.11 mm1
b = 10.0160 (19) ÅT = 173 K
c = 25.907 (5) Å0.35 × 0.09 × 0.08 mm
β = 92.845 (4)°
Data collection top
Bruker Kappa DUO APEXII
diffractometer
3303 independent reflections
Absorption correction: multi-scan
(TWINABS; Sheldrick, 1997)
2887 reflections with I > 2σ(I)
Tmin = 0.964, Tmax = 0.992Rint = 0.063
87638 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0500 restraints
wR(F2) = 0.154H-atom parameters constrained
S = 1.09Δρmax = 0.25 e Å3
3303 reflectionsΔρmin = 0.23 e Å3
191 parameters
Special details top

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

Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O10.9485 (3)0.30392 (15)0.16095 (6)0.0339 (4)
O20.3498 (3)0.50967 (15)0.23136 (6)0.0355 (4)
O30.8175 (4)0.63590 (18)0.49727 (6)0.0449 (4)
O41.1513 (4)0.7098 (2)0.45470 (7)0.0522 (5)
N10.9499 (4)0.63878 (18)0.45839 (7)0.0328 (4)
C10.8059 (4)0.4022 (2)0.13399 (8)0.0282 (4)
C20.8774 (5)0.2756 (2)0.20963 (8)0.0323 (4)
H20.97470.20630.22750.039*
C30.6800 (4)0.33749 (19)0.23490 (7)0.0281 (4)
C40.5276 (4)0.44552 (19)0.20968 (7)0.0264 (4)
C50.5991 (4)0.47384 (19)0.15623 (7)0.0260 (4)
C60.4653 (5)0.5734 (2)0.12658 (8)0.0333 (5)
H60.32350.62330.14100.040*
C70.5368 (5)0.6000 (2)0.07681 (9)0.0383 (5)
H70.44570.66810.05720.046*
C80.7441 (5)0.5262 (3)0.05552 (8)0.0402 (5)
H80.79270.54450.02120.048*
C90.8801 (5)0.4268 (2)0.08354 (8)0.0364 (5)
H91.02050.37670.06880.044*
C100.6125 (5)0.2953 (2)0.28877 (8)0.0343 (5)
H10A0.69710.20720.29600.041*
H10B0.41310.28360.28950.041*
C110.7026 (4)0.39038 (19)0.33199 (7)0.0273 (4)
C120.5763 (5)0.3825 (2)0.37937 (8)0.0347 (5)
H120.43300.32030.38310.042*
C130.6553 (5)0.4630 (2)0.42049 (8)0.0341 (5)
H130.56820.45690.45230.041*
C140.8652 (4)0.55301 (19)0.41435 (7)0.0273 (4)
C150.9971 (4)0.5640 (2)0.36858 (8)0.0313 (4)
H151.14110.62610.36530.038*
C160.9136 (4)0.4816 (2)0.32739 (8)0.0309 (4)
H161.00180.48790.29570.037*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0369 (8)0.0348 (7)0.0303 (7)0.0077 (7)0.0045 (6)0.0026 (6)
O20.0400 (8)0.0371 (8)0.0303 (8)0.0037 (7)0.0105 (6)0.0019 (6)
O30.0529 (10)0.0535 (10)0.0290 (8)0.0090 (8)0.0089 (7)0.0110 (7)
O40.0546 (11)0.0583 (11)0.0440 (10)0.0286 (9)0.0047 (8)0.0118 (8)
N10.0365 (9)0.0334 (9)0.0284 (9)0.0030 (8)0.0001 (7)0.0015 (7)
C10.0308 (9)0.0287 (9)0.0250 (9)0.0015 (8)0.0003 (8)0.0025 (7)
C20.0409 (11)0.0274 (9)0.0282 (10)0.0017 (9)0.0023 (9)0.0006 (8)
C30.0368 (10)0.0251 (9)0.0222 (9)0.0056 (8)0.0003 (8)0.0022 (7)
C40.0315 (9)0.0242 (8)0.0237 (9)0.0051 (8)0.0034 (8)0.0030 (7)
C50.0282 (9)0.0256 (9)0.0243 (9)0.0035 (7)0.0019 (8)0.0025 (7)
C60.0362 (10)0.0321 (10)0.0316 (10)0.0035 (9)0.0018 (9)0.0024 (8)
C70.0425 (12)0.0404 (11)0.0318 (11)0.0005 (10)0.0014 (9)0.0089 (9)
C80.0433 (12)0.0524 (13)0.0251 (10)0.0064 (11)0.0037 (9)0.0058 (9)
C90.0358 (11)0.0461 (12)0.0278 (10)0.0012 (10)0.0067 (9)0.0044 (9)
C100.0513 (13)0.0276 (9)0.0239 (10)0.0063 (9)0.0009 (9)0.0014 (8)
C110.0334 (10)0.0260 (9)0.0222 (9)0.0002 (8)0.0005 (8)0.0026 (7)
C120.0384 (11)0.0375 (11)0.0286 (10)0.0126 (9)0.0042 (9)0.0005 (8)
C130.0365 (11)0.0414 (11)0.0249 (9)0.0062 (9)0.0065 (9)0.0004 (8)
C140.0290 (9)0.0290 (9)0.0238 (9)0.0007 (8)0.0001 (7)0.0001 (7)
C150.0320 (10)0.0334 (10)0.0285 (10)0.0060 (8)0.0017 (8)0.0022 (8)
C160.0337 (10)0.0340 (10)0.0253 (9)0.0029 (9)0.0054 (8)0.0017 (8)
Geometric parameters (Å, º) top
O1—C21.356 (3)C7—H70.9500
O1—C11.379 (3)C8—C91.385 (3)
O2—C41.243 (2)C8—H80.9500
O3—N11.227 (2)C9—H90.9500
O4—N11.228 (2)C10—C111.519 (3)
N1—C141.472 (3)C10—H10A0.9900
C1—C51.394 (3)C10—H10B0.9900
C1—C91.397 (3)C11—C161.393 (3)
C2—C31.350 (3)C11—C121.406 (3)
C2—H20.9500C12—C131.376 (3)
C3—C41.453 (3)C12—H120.9500
C3—C101.511 (3)C13—C141.387 (3)
C4—C51.473 (3)C13—H130.9500
C5—C61.403 (3)C14—C151.385 (3)
C6—C71.379 (3)C15—C161.394 (3)
C6—H60.9500C15—H150.9500
C7—C81.396 (3)C16—H160.9500
C2—O1—C1118.18 (16)C8—C9—C1118.4 (2)
O3—N1—O4122.80 (18)C8—C9—H9120.8
O3—N1—C14118.74 (17)C1—C9—H9120.8
O4—N1—C14118.46 (18)C3—C10—C11115.84 (17)
O1—C1—C5121.51 (18)C3—C10—H10A108.3
O1—C1—C9116.75 (18)C11—C10—H10A108.3
C5—C1—C9121.74 (19)C3—C10—H10B108.3
C3—C2—O1125.48 (19)C11—C10—H10B108.3
C3—C2—H2117.3H10A—C10—H10B107.4
O1—C2—H2117.3C16—C11—C12118.41 (18)
C2—C3—C4119.50 (18)C16—C11—C10122.68 (18)
C2—C3—C10121.08 (19)C12—C11—C10118.86 (18)
C4—C3—C10119.42 (18)C13—C12—C11121.51 (19)
O2—C4—C3122.79 (18)C13—C12—H12119.2
O2—C4—C5122.13 (18)C11—C12—H12119.2
C3—C4—C5115.08 (17)C12—C13—C14118.41 (18)
C1—C5—C6118.21 (18)C12—C13—H13120.8
C1—C5—C4120.18 (18)C14—C13—H13120.8
C6—C5—C4121.60 (18)C15—C14—C13122.27 (19)
C7—C6—C5121.0 (2)C15—C14—N1119.37 (18)
C7—C6—H6119.5C13—C14—N1118.35 (17)
C5—C6—H6119.5C14—C15—C16118.37 (19)
C6—C7—C8119.5 (2)C14—C15—H15120.8
C6—C7—H7120.2C16—C15—H15120.8
C8—C7—H7120.2C11—C16—C15121.03 (18)
C9—C8—C7121.2 (2)C11—C16—H16119.5
C9—C8—H8119.4C15—C16—H16119.5
C7—C8—H8119.4
C2—O1—C1—C51.8 (3)C7—C8—C9—C10.3 (4)
C2—O1—C1—C9178.58 (19)O1—C1—C9—C8179.1 (2)
C1—O1—C2—C31.4 (3)C5—C1—C9—C80.5 (3)
O1—C2—C3—C40.9 (3)C2—C3—C10—C11107.3 (2)
O1—C2—C3—C10178.39 (19)C4—C3—C10—C1173.4 (3)
C2—C3—C4—O2177.5 (2)C3—C10—C11—C1623.1 (3)
C10—C3—C4—O23.2 (3)C3—C10—C11—C12159.7 (2)
C2—C3—C4—C52.6 (3)C16—C11—C12—C130.4 (3)
C10—C3—C4—C5176.76 (17)C10—C11—C12—C13177.8 (2)
O1—C1—C5—C6179.24 (18)C11—C12—C13—C140.1 (3)
C9—C1—C5—C60.3 (3)C12—C13—C14—C150.3 (3)
O1—C1—C5—C40.1 (3)C12—C13—C14—N1179.9 (2)
C9—C1—C5—C4179.63 (19)O3—N1—C14—C15174.2 (2)
O2—C4—C5—C1177.96 (19)O4—N1—C14—C156.2 (3)
C3—C4—C5—C12.1 (3)O3—N1—C14—C136.2 (3)
O2—C4—C5—C61.3 (3)O4—N1—C14—C13173.4 (2)
C3—C4—C5—C6178.63 (18)C13—C14—C15—C160.4 (3)
C1—C5—C6—C70.1 (3)N1—C14—C15—C16179.96 (19)
C4—C5—C6—C7179.1 (2)C12—C11—C16—C150.3 (3)
C5—C6—C7—C80.4 (3)C10—C11—C16—C15177.6 (2)
C6—C7—C8—C90.2 (4)C14—C15—C16—C110.0 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C2—H2···O2i0.952.383.322 (3)170
C7—H7···O3ii0.952.563.491 (3)166
C9—H9···O4iii0.952.423.355 (3)167
C13—H13···O3iv0.952.533.382 (3)149
C16—H16···O2v0.952.463.378 (3)163
Symmetry codes: (i) x+3/2, y1/2, z+1/2; (ii) x1/2, y+3/2, z1/2; (iii) x+5/2, y1/2, z+1/2; (iv) x+1, y+1, z+1; (v) x+1, y, z.

Experimental details

Crystal data
Chemical formulaC16H11NO4
Mr281.26
Crystal system, space groupMonoclinic, P21/n
Temperature (K)173
a, b, c (Å)4.9246 (9), 10.0160 (19), 25.907 (5)
β (°) 92.845 (4)
V3)1276.3 (4)
Z4
Radiation typeMo Kα
µ (mm1)0.11
Crystal size (mm)0.35 × 0.09 × 0.08
Data collection
DiffractometerBruker Kappa DUO APEXII
diffractometer
Absorption correctionMulti-scan
(TWINABS; Sheldrick, 1997)
Tmin, Tmax0.964, 0.992
No. of measured, independent and
observed [I > 2σ(I)] reflections
87638, 3303, 2887
Rint0.063
(sin θ/λ)max1)0.648
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.050, 0.154, 1.09
No. of reflections3303
No. of parameters191
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.25, 0.23

Computer programs: APEX2 (Bruker, 2006), SAINT (Bruker, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C2—H2···O2i0.952.383.322 (3)170
C7—H7···O3ii0.952.563.491 (3)166
C9—H9···O4iii0.952.423.355 (3)167
C13—H13···O3iv0.952.533.382 (3)149
C16—H16···O2v0.952.463.378 (3)163
Symmetry codes: (i) x+3/2, y1/2, z+1/2; (ii) x1/2, y+3/2, z1/2; (iii) x+5/2, y1/2, z+1/2; (iv) x+1, y+1, z+1; (v) x+1, y, z.
 

Acknowledgements

We thank the University of KwaZulu-Natal and the South Africa Research Chairs initiative of the Department of Science and Technology for financial support and the National Research Foundation of South Africa for a bursary for KG.

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