organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

2,2,6-Tri­methyl-5-[2-(4-methyl­phen­yl)ethyn­yl]-4H-1,3-dioxin-4-one

aBioMat–Physics Department, Universidade Estadual Paulista Júlio de Mesquita Filho, UNESP, 17033-360 Bauru, SP, Brazil, bDepartment of Chemistry, Universidade Federal de São Carlos, 13565-905 São Carlos, SP, Brazil, cDepartamento de Farmácia, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, São Paulo-SP, Brazil, and dDepartment of Chemistry, University of Malaya, Kuala Lumpur 50603, Malaysia
*Correspondence e-mail: ignez@fc.unesp.br

(Received 5 October 2009; accepted 7 October 2009; online 17 October 2009)

The 1,3-dioxin-4-one ring in the title compound, C16H16O3, is in a half-boat conformation with the quaternary O—C(CH3)2—O atom lying 0.546 (1) Å out of the plane defined by the remaining five atoms. The crystal structure is consolidated by C—H⋯O contacts that lead to supra­molecular layers.

Related literature

For background to potassium organotrifluoro­borate salts in organic synthesis, see: Caracelli et al. (2007[Caracelli, I., Stefani, H. A., Vieira, A. S., Machado, M. M. P. & Zukerman-Schpector, J. (2007). Z. Kristallogr. New Cryst. Struct. 222, 345-346.]); Stefani et al. (2007[Stefani, H. A., Cella, R. & Vieira, A. S. (2007). Tetrahedron, 63, 3623-3658.]); Vieira et al. (2008[Vieira, A. S., Fiorante, P. F., Zukerman-Schpector, J., Alves, D., Botteselle, G. V. & Stefani, H. A. (2008). Tetrahedron, 64, 7234-7241.]). For related structures, see: Le & Pagenkopf (2004[Le, J. C.-D. & Pagenkopf, B. L. (2004). Org. Lett. 6, 4097-4099.]); Zukerman-Schpector et al. (2009[Zukerman-Schpector, J., Vieira, A. S., Stefani, H. A. & Tiekink, E. R. T. (2009). Acta Cryst. E65, o1694.]). For conformational analysis, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]); Iulek & Zukerman-Schpector (1997[Iulek, J. & Zukerman-Schpector, J. (1997). Quim. Nova, 20, 433-434.]).

[Scheme 1]

Experimental

Crystal data
  • C16H16O3

  • Mr = 256.29

  • Orthorhombic, P b c a

  • a = 14.8486 (15) Å

  • b = 9.621 (1) Å

  • c = 18.9438 (18) Å

  • V = 2706.3 (5) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 100 K

  • 0.20 × 0.10 × 0.05 mm

Data collection
  • Bruker SMART APEXII diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.911, Tmax = 1

  • 32445 measured reflections

  • 2382 independent reflections

  • 1727 reflections with I > 2σ(I)

  • Rint = 0.083

Refinement
  • R[F2 > 2σ(F2)] = 0.038

  • wR(F2) = 0.096

  • S = 1.04

  • 2382 reflections

  • 174 parameters

  • H-atom parameters constrained

  • Δρmax = 0.19 e Å−3

  • Δρmin = −0.17 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C16—H16A⋯O1i 0.98 2.52 3.363 (2) 144
C7—H7⋯O1ii 0.95 2.41 3.344 (2) 169
Symmetry codes: (i) -x+1, -y, -z+1; (ii) [-x+{\script{3\over 2}}, y+{\script{1\over 2}}, z].

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SIR97 (Altomare et al., 1999[Altomare, A., Burla, M. C., Camalli, M., Cascarano, G. L., Giacovazzo, C., Guagliardi, A., Moliterni, A. G. G., Polidori, G. & Spagna, R. (1999). J. Appl. Cryst. 32, 115-119.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and DIAMOND (Brandenburg, 2006[Brandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]).

Supporting information


Comment top

The potential use of potassium organotrifluoroborate salts as intermediates in organic synthesis motivates continuing interest (Caracelli et al., 2007; Stefani et al., 2007; Vieira et al. 2008). As a part of on-going studies, the crystal structure of the title compound, (I), is reported herein, which was obtained by the Suzuki-Miyaura palladium-catalyzed cross-coupling reaction of 5-iodo-1,3-dioxin-4-one and a potassium alkynyltrifluoroborate salt.

The molecular structure of (I), Fig. 1, shows the 1,3-dioxin-4-one ring to adopt a half-boat conformation with the C12 atom being displaced 0.546 (1) Å out of the plane defined by the remaining five atoms. The ring-puckering parameters are q2 = 0.346 (2) Å, q3 = 0.182 (2) Å, Q = 0.391 (2) Å, and φ2 = 299.3 (3)° (Cremer & Pople, 1975; Iulek & Zukerman-Schpector, 1997). A similar conformation has been observed in related structures containing the 1,3-dioxin-4-one ring (Le & Pagenkopf, 2004; Zukerman-Schpector et al., 2009). The presence of C—H···O contacts involving the bifurcated carbonyl-O1 atom interacting with two different molecules leads to a layer architecture in the ab plane, Fig. 2. These stack along the c direction to form the crystal structure.

Related literature top

For background on potassium organotrifluoroborate salts in organic synthesis, see: Caracelli et al. (2007); Stefani et al. (2007); Vieira et al. (2008). For related structures, see: Le & Pagenkopf (2004); Zukerman-Schpector et al. (2009). For conformational analysis, see: Cremer & Pople (1975); Iulek & Zukerman-Schpector (1997).

Experimental top

The treatment of potassium p-tolylethynyltrifluoroborate (244 mg, 1.1 equiv) with K2CO3 (2 mmol, 276 mg) in 3 ml of degassed THF water (2:1) under an inert atmosphere, followed by the addition of PdCl2 (3.5 mg, 2.0 mol%) and 2,2,6-trimethyl-5-iodo-1,3-dioxin-4-one 1 (1.0 equiv) with vigorous stirring for 3 h at 353 K, afforded compound (I) in 72% yield after column chromatography. Single crystals were obtained by slow evaporation from ethyl acetate.

Refinement top

The H atoms were positioned with idealized geometry using a riding model with C—H = 0.95–0.98 Å, and with Uiso set to 1.2 times (1.5 for methyl) Ueq(parent atom).

Structure description top

The potential use of potassium organotrifluoroborate salts as intermediates in organic synthesis motivates continuing interest (Caracelli et al., 2007; Stefani et al., 2007; Vieira et al. 2008). As a part of on-going studies, the crystal structure of the title compound, (I), is reported herein, which was obtained by the Suzuki-Miyaura palladium-catalyzed cross-coupling reaction of 5-iodo-1,3-dioxin-4-one and a potassium alkynyltrifluoroborate salt.

The molecular structure of (I), Fig. 1, shows the 1,3-dioxin-4-one ring to adopt a half-boat conformation with the C12 atom being displaced 0.546 (1) Å out of the plane defined by the remaining five atoms. The ring-puckering parameters are q2 = 0.346 (2) Å, q3 = 0.182 (2) Å, Q = 0.391 (2) Å, and φ2 = 299.3 (3)° (Cremer & Pople, 1975; Iulek & Zukerman-Schpector, 1997). A similar conformation has been observed in related structures containing the 1,3-dioxin-4-one ring (Le & Pagenkopf, 2004; Zukerman-Schpector et al., 2009). The presence of C—H···O contacts involving the bifurcated carbonyl-O1 atom interacting with two different molecules leads to a layer architecture in the ab plane, Fig. 2. These stack along the c direction to form the crystal structure.

For background on potassium organotrifluoroborate salts in organic synthesis, see: Caracelli et al. (2007); Stefani et al. (2007); Vieira et al. (2008). For related structures, see: Le & Pagenkopf (2004); Zukerman-Schpector et al. (2009). For conformational analysis, see: Cremer & Pople (1975); Iulek & Zukerman-Schpector (1997).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) showing atom labelling scheme and displacement ellipsoids at the 50% probability level (arbitrary spheres for the H atoms).
[Figure 2] Fig. 2. Supramolecular association via C—H···O contacts (orange dashed lines) leading to a layer architecture in the structure of (I).
2,2,6-Trimethyl-5-[2-(4-methylphenyl)ethynyl]-4H-1,3-dioxin-4-one top
Crystal data top
C16H16O3F(000) = 1088
Mr = 256.29Dx = 1.258 Mg m3
Orthorhombic, PbcaMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2abCell parameters from 4513 reflections
a = 14.8486 (15) Åθ = 2.7–23.7°
b = 9.621 (1) ŵ = 0.09 mm1
c = 18.9438 (18) ÅT = 100 K
V = 2706.3 (5) Å3Plate, colourless
Z = 80.20 × 0.10 × 0.05 mm
Data collection top
Bruker SMART APEXII
diffractometer
2382 independent reflections
Radiation source: sealed tube1727 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.083
φ and ω scansθmax = 25.0°, θmin = 2.2°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 1717
Tmin = 0.911, Tmax = 1k = 811
32445 measured reflectionsl = 2222
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)] = 0.038Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.096H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.0366P)2 + 1.3345P]
where P = (Fo2 + 2Fc2)/3
2382 reflections(Δ/σ)max < 0.001
174 parametersΔρmax = 0.19 e Å3
0 restraintsΔρmin = 0.17 e Å3
Crystal data top
C16H16O3V = 2706.3 (5) Å3
Mr = 256.29Z = 8
Orthorhombic, PbcaMo Kα radiation
a = 14.8486 (15) ŵ = 0.09 mm1
b = 9.621 (1) ÅT = 100 K
c = 18.9438 (18) Å0.20 × 0.10 × 0.05 mm
Data collection top
Bruker SMART APEXII
diffractometer
2382 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
1727 reflections with I > 2σ(I)
Tmin = 0.911, Tmax = 1Rint = 0.083
32445 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0380 restraints
wR(F2) = 0.096H-atom parameters constrained
S = 1.04Δρmax = 0.19 e Å3
2382 reflectionsΔρmin = 0.17 e Å3
174 parameters
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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
O10.44450 (8)0.15682 (13)0.61722 (7)0.0282 (3)
O20.33370 (8)0.01835 (13)0.58506 (6)0.0238 (3)
O30.36181 (8)0.21026 (13)0.54478 (6)0.0225 (3)
C11.01927 (13)0.0304 (3)0.71504 (11)0.0403 (6)
H1A1.05390.07040.67600.060*
H1B1.02110.09350.75560.060*
H1C1.04540.05940.72840.060*
C20.92289 (12)0.0097 (2)0.69219 (9)0.0261 (5)
C30.85526 (12)0.0999 (2)0.71392 (9)0.0260 (4)
H30.86980.17530.74430.031*
C40.76733 (12)0.08212 (19)0.69223 (9)0.0234 (4)
H40.72210.14420.70840.028*
C50.74413 (12)0.02656 (19)0.64657 (8)0.0208 (4)
C60.81219 (12)0.1170 (2)0.62428 (10)0.0254 (4)
H60.79820.19090.59290.030*
C70.89939 (12)0.0998 (2)0.64750 (10)0.0273 (5)
H70.94440.16370.63280.033*
C80.65282 (13)0.0444 (2)0.62380 (9)0.0230 (4)
C90.57567 (12)0.06035 (19)0.60694 (9)0.0226 (4)
C100.48224 (12)0.07787 (19)0.59006 (9)0.0216 (4)
C110.42172 (12)0.0405 (2)0.60048 (9)0.0222 (4)
C120.30049 (12)0.12229 (19)0.58355 (10)0.0218 (4)
C130.45014 (12)0.19506 (19)0.55944 (9)0.0213 (4)
C140.28969 (12)0.1777 (2)0.65791 (9)0.0259 (5)
H14A0.24780.11830.68410.039*
H14B0.26590.27270.65610.039*
H14C0.34830.17810.68160.039*
C150.21469 (12)0.1198 (2)0.54194 (10)0.0278 (5)
H15A0.17040.06120.56610.042*
H15B0.22650.08200.49480.042*
H15C0.19100.21450.53770.042*
C160.50431 (13)0.3156 (2)0.53576 (9)0.0258 (4)
H16A0.51160.31200.48440.039*
H16B0.56360.31260.55840.039*
H16C0.47350.40190.54890.039*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0285 (7)0.0213 (7)0.0350 (8)0.0050 (6)0.0016 (6)0.0007 (6)
O20.0197 (7)0.0194 (7)0.0322 (7)0.0015 (6)0.0015 (6)0.0009 (6)
O30.0202 (7)0.0228 (7)0.0244 (6)0.0018 (6)0.0003 (5)0.0029 (6)
C10.0234 (12)0.0672 (17)0.0302 (11)0.0004 (11)0.0027 (9)0.0092 (11)
C20.0218 (10)0.0367 (12)0.0199 (9)0.0010 (9)0.0010 (8)0.0103 (8)
C30.0266 (11)0.0284 (11)0.0229 (9)0.0036 (9)0.0020 (8)0.0008 (8)
C40.0245 (11)0.0238 (10)0.0220 (9)0.0055 (9)0.0021 (8)0.0013 (8)
C50.0201 (9)0.0243 (10)0.0179 (8)0.0008 (8)0.0006 (7)0.0051 (8)
C60.0283 (11)0.0233 (11)0.0246 (10)0.0004 (9)0.0033 (8)0.0001 (8)
C70.0231 (10)0.0316 (11)0.0271 (10)0.0089 (9)0.0074 (8)0.0065 (9)
C80.0242 (11)0.0242 (11)0.0206 (9)0.0004 (8)0.0019 (8)0.0007 (8)
C90.0235 (11)0.0244 (10)0.0200 (9)0.0003 (8)0.0028 (8)0.0003 (8)
C100.0209 (10)0.0247 (11)0.0193 (9)0.0024 (8)0.0019 (7)0.0021 (8)
C110.0231 (10)0.0232 (11)0.0202 (9)0.0055 (8)0.0008 (7)0.0029 (8)
C120.0195 (10)0.0197 (10)0.0262 (10)0.0024 (8)0.0021 (8)0.0020 (8)
C130.0219 (10)0.0255 (11)0.0165 (8)0.0018 (8)0.0012 (7)0.0041 (8)
C140.0243 (10)0.0272 (11)0.0262 (10)0.0036 (9)0.0017 (8)0.0001 (8)
C150.0222 (10)0.0287 (11)0.0325 (10)0.0020 (9)0.0023 (8)0.0028 (9)
C160.0266 (10)0.0257 (11)0.0250 (9)0.0006 (9)0.0034 (8)0.0004 (8)
Geometric parameters (Å, º) top
O1—C111.211 (2)C6—H60.9500
O2—C111.356 (2)C7—H70.9500
O2—C121.440 (2)C8—C91.199 (2)
O3—C131.349 (2)C9—C101.434 (3)
O3—C121.444 (2)C10—C131.355 (3)
C1—C21.508 (3)C10—C111.464 (3)
C1—H1A0.9800C12—C151.498 (2)
C1—H1B0.9800C12—C141.515 (2)
C1—H1C0.9800C13—C161.481 (3)
C2—C31.390 (3)C14—H14A0.9800
C2—C71.395 (3)C14—H14B0.9800
C3—C41.379 (2)C14—H14C0.9800
C3—H30.9500C15—H15A0.9800
C4—C51.400 (2)C15—H15B0.9800
C4—H40.9500C15—H15C0.9800
C5—C61.399 (3)C16—H16A0.9800
C5—C81.433 (3)C16—H16B0.9800
C6—C71.378 (3)C16—H16C0.9800
C11—O2—C12118.82 (14)O1—C11—O2118.10 (17)
C13—O3—C12116.42 (14)O1—C11—C10125.63 (17)
C2—C1—H1A109.5O2—C11—C10116.10 (16)
C2—C1—H1B109.5O2—C12—O3110.17 (13)
H1A—C1—H1B109.5O2—C12—C15106.64 (15)
C2—C1—H1C109.5O3—C12—C15106.15 (14)
H1A—C1—H1C109.5O2—C12—C14110.40 (15)
H1B—C1—H1C109.5O3—C12—C14109.47 (15)
C3—C2—C7118.06 (17)C15—C12—C14113.88 (15)
C3—C2—C1121.20 (19)O3—C13—C10121.37 (17)
C7—C2—C1120.74 (18)O3—C13—C16112.39 (16)
C4—C3—C2121.19 (18)C10—C13—C16126.19 (16)
C4—C3—H3119.4C12—C14—H14A109.5
C2—C3—H3119.4C12—C14—H14B109.5
C3—C4—C5120.65 (17)H14A—C14—H14B109.5
C3—C4—H4119.7C12—C14—H14C109.5
C5—C4—H4119.7H14A—C14—H14C109.5
C6—C5—C4118.24 (17)H14B—C14—H14C109.5
C6—C5—C8121.20 (17)C12—C15—H15A109.5
C4—C5—C8120.56 (17)C12—C15—H15B109.5
C7—C6—C5120.52 (18)H15A—C15—H15B109.5
C7—C6—H6119.7C12—C15—H15C109.5
C5—C6—H6119.7H15A—C15—H15C109.5
C6—C7—C2121.31 (18)H15B—C15—H15C109.5
C6—C7—H7119.3C13—C16—H16A109.5
C2—C7—H7119.3C13—C16—H16B109.5
C9—C8—C5177.91 (18)H16A—C16—H16B109.5
C8—C9—C10177.35 (19)C13—C16—H16C109.5
C13—C10—C9122.26 (17)H16A—C16—H16C109.5
C13—C10—C11119.30 (16)H16B—C16—H16C109.5
C9—C10—C11118.19 (16)
C7—C2—C3—C40.1 (3)C13—C10—C11—O26.8 (2)
C1—C2—C3—C4179.09 (17)C9—C10—C11—O2178.82 (15)
C2—C3—C4—C51.1 (3)C11—O2—C12—O345.9 (2)
C3—C4—C5—C60.7 (3)C11—O2—C12—C15160.69 (14)
C3—C4—C5—C8179.67 (17)C11—O2—C12—C1475.12 (19)
C4—C5—C6—C70.7 (3)C13—O3—C12—O245.2 (2)
C8—C5—C6—C7178.97 (17)C13—O3—C12—C15160.28 (15)
C5—C6—C7—C21.7 (3)C13—O3—C12—C1476.39 (18)
C3—C2—C7—C61.2 (3)C12—O3—C13—C1020.6 (2)
C1—C2—C7—C6177.71 (18)C12—O3—C13—C16161.70 (14)
C12—O2—C11—O1163.63 (15)C9—C10—C13—O3179.15 (15)
C12—O2—C11—C1020.8 (2)C11—C10—C13—O36.7 (2)
C13—C10—C11—O1168.37 (17)C9—C10—C13—C163.5 (3)
C9—C10—C11—O16.0 (3)C11—C10—C13—C16170.62 (16)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C16—H16A···O1i0.982.523.363 (2)144
C7—H7···O1ii0.952.413.344 (2)169
Symmetry codes: (i) x+1, y, z+1; (ii) x+3/2, y+1/2, z.

Experimental details

Crystal data
Chemical formulaC16H16O3
Mr256.29
Crystal system, space groupOrthorhombic, Pbca
Temperature (K)100
a, b, c (Å)14.8486 (15), 9.621 (1), 18.9438 (18)
V3)2706.3 (5)
Z8
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.20 × 0.10 × 0.05
Data collection
DiffractometerBruker SMART APEXII
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.911, 1
No. of measured, independent and
observed [I > 2σ(I)] reflections
32445, 2382, 1727
Rint0.083
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.038, 0.096, 1.04
No. of reflections2382
No. of parameters174
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.19, 0.17

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SIR97 (Altomare et al., 1999), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2006), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C16—H16A···O1i0.982.523.363 (2)144
C7—H7···O1ii0.952.413.344 (2)169
Symmetry codes: (i) x+1, y, z+1; (ii) x+3/2, y+1/2, z.
 

Acknowledgements

The authors thank FAPESP [grant Nos. 07/59404-2 (HAS) and 08/02531-5 (JZ-S)], CNPq [grant Nos. 472237/2008-0 (IC), 300613/2007 (HAS), 307121/2006-0 (JZ-S)] and CAPES for financial support.

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