organic compounds
2-[(2-Fluorophenyl)(1H-indol-3-yl)methyl]-1H-indole
aDepartment of Chemistry, Kuvempu University, P G Centre, Kadur 577 548, India, bInstitution of Excellence, University of Mysore, Manasagangotri, Mysuru 570 006, India, cDepartment of Chemistry, Yuvarajas College, University of Mysore, Mysuru 570 005, India, and dDepartment of Studies in Physics, University of Mysore, Manasagangotri, Mysuru 570 006, India
*Correspondence e-mail: lokanath@physics.uni-mysore.ac.in
In the title compound, C23H17FN2, the indole ring systems are oriented orthogonally, as indicated by the dihedral angle between them of 88.49 (5)°. The fluorophenyl ring is nearly perpendicular to one of the indole ring systems [dihedral angle = 85.31 (16)°] and twisted by 63.6 (6)° from the other. In the crystal, N—H⋯π, C—H⋯π and C—H⋯F interactions occur, forming a three-dimensional network.
Keywords: crystal structure; indole; hydrogen bonding.
CCDC reference: 1481317
Structure description
Indoles have diverse biological activities and pharmaceutical applications (Diss et al., 2013). In particular, bis(indolyl) methane and its derivatives are known to be important intermediates in organic synthesis and exhibit various physiological properties (Ishikawa et al., 2008). As part of our ongoing research in this area (Walki et al., 2015), the synthesis and of the title compound, C23H17N2F, is reported herein (Fig. 1).
Both the indole ring systems are essentially planar with dihedral angles of 1.37 (1) and 2.48 (1)°, between the two fused ring systems N1/C2–C9 and N13/C11/C12/C14–C19, respectively. The indole ring systems are oriented orthogonally with respect to each other, as indicated by the dihedral angle value of 88.49 (5)°. The fluorophenyl ring is nearly perpendicular to one of the indole ring systems [N1/C2–C9; dihedral angle = 85.31 (16)°] whereas it is twisted by 63.6 (6)° from the other indole ring system.
In the crystal, the C5—H5⋯F26 hydrogen bond (Table 1) links molecules into R22(18) inversion dimers. C23—H23⋯π chains connect these dimers, forming rectangular columns running down the b axis, and these chains are further reinforced by C24—H24⋯π interactions (Fig. 2 left). Further N1—H1⋯π and C3—H3⋯π interactions between the molecules results in sheets parallel to the bc plane (Fig. 2 right). The sheets are interlinked via N13—H13⋯π interactions along the a axis, forming a three-dimensional network (Fig. 3).
Synthesis and crystallization
To a flask containing 5 ml of glacial acetic acid, indole (2 mmol, 0.23 g) was added under stirring until all the indole had dissolved. Then 2-fluorobenzaldehyde (1 mmol, 0.14 g) was added under vigorous stirring. The reaction mixture was allowed to stir over 4 to 6 h, during which time the reaction solution turned from light yellow to light pink to dark red colour. The product was detected by TLC (100% CH2Cl2). After the completion of the reaction, the reaction mixture was added to ice-cold water. The product that separated out from the reaction mixture was filtered and washed with water. The crude product was further purified by recrystallization using methanol as solvent to obtain orange blocks of the title compound in 81% yield, m.p. = 178–180°C.
Refinement
Crystal data, data collection and structure .
details are summarized in Table 2
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Structural data
CCDC reference: 1481317
10.1107/S2414314616008385/hb4049sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S2414314616008385/hb4049Isup2.hkl
Supporting information file. DOI: 10.1107/S2414314616008385/hb4049Isup3.cml
Data collection: APEX2 (Bruker, 2013); cell
SAINT (Bruker, 2013); data reduction: SAINT (Bruker, 2013); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: PLATON (Spek, 2009).C23H17FN2 | F(000) = 712 |
Mr = 340.39 | Dx = 1.302 Mg m−3 |
Monoclinic, P21/c | Cu Kα radiation, λ = 1.54178 Å |
Hall symbol: -P 2ybc | Cell parameters from 2845 reflections |
a = 10.0822 (5) Å | θ = 4.4–64.2° |
b = 9.7969 (4) Å | µ = 0.67 mm−1 |
c = 17.6310 (8) Å | T = 296 K |
β = 94.262 (2)° | Block, orange |
V = 1736.67 (14) Å3 | 0.29 × 0.27 × 0.25 mm |
Z = 4 |
Bruker X8 Proteum diffractometer | 2845 independent reflections |
Radiation source: Rotating Anode | 2480 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.036 |
Detector resolution: 18.4 pixels mm-1 | θmax = 64.2°, θmin = 4.4° |
φ and ω scans | h = −11→11 |
Absorption correction: multi-scan (SADABS; Bruker, 2013) | k = −10→11 |
Tmin = 0.823, Tmax = 0.845 | l = −20→11 |
7737 measured reflections |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.038 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.105 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.07 | w = 1/[σ2(Fo2) + (0.0587P)2 + 0.3295P] where P = (Fo2 + 2Fc2)/3 |
2845 reflections | (Δ/σ)max = 0.001 |
235 parameters | Δρmax = 0.23 e Å−3 |
0 restraints | Δρmin = −0.18 e Å−3 |
Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell esds are taken into account in the estimation of distances, angles and torsion angles |
Refinement. Refinement on F2 for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The observed criterion of F2 > 2sigma(F2) is used only for calculating -R-factor-obs 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. |
x | y | z | Uiso*/Ueq | ||
F26 | 0.00536 (8) | 0.57139 (8) | 0.42643 (5) | 0.0316 (3) | |
N1 | 0.24195 (13) | 0.72377 (13) | 0.64897 (7) | 0.0302 (4) | |
N13 | 0.52338 (12) | 0.93784 (13) | 0.38606 (7) | 0.0292 (4) | |
C2 | 0.20504 (14) | 0.85811 (15) | 0.64054 (9) | 0.0260 (4) | |
C3 | 0.18320 (15) | 0.95771 (17) | 0.69494 (10) | 0.0334 (5) | |
C4 | 0.15144 (15) | 1.08692 (17) | 0.66901 (11) | 0.0358 (5) | |
C5 | 0.14059 (15) | 1.11795 (16) | 0.59132 (11) | 0.0343 (5) | |
C6 | 0.16105 (14) | 1.01950 (15) | 0.53726 (9) | 0.0271 (4) | |
C7 | 0.19387 (13) | 0.88639 (14) | 0.56189 (8) | 0.0227 (4) | |
C8 | 0.22413 (13) | 0.76180 (14) | 0.52312 (8) | 0.0218 (4) | |
C9 | 0.25164 (15) | 0.66702 (15) | 0.57843 (9) | 0.0270 (4) | |
C10 | 0.22554 (14) | 0.74567 (14) | 0.43815 (8) | 0.0220 (4) | |
C11 | 0.33021 (14) | 0.83498 (14) | 0.40622 (8) | 0.0228 (4) | |
C12 | 0.46077 (14) | 0.84799 (15) | 0.43141 (9) | 0.0276 (5) | |
C14 | 0.43318 (14) | 0.98676 (14) | 0.33069 (8) | 0.0242 (4) | |
C15 | 0.44803 (16) | 1.08041 (15) | 0.27228 (9) | 0.0295 (5) | |
C16 | 0.33645 (16) | 1.11427 (15) | 0.22625 (9) | 0.0304 (5) | |
C17 | 0.21197 (16) | 1.05838 (15) | 0.23816 (9) | 0.0294 (4) | |
C18 | 0.19700 (14) | 0.96412 (14) | 0.29521 (8) | 0.0244 (4) | |
C19 | 0.30918 (14) | 0.92501 (14) | 0.34225 (8) | 0.0215 (4) | |
C20 | 0.23638 (14) | 0.59460 (14) | 0.41749 (8) | 0.0232 (4) | |
C21 | 0.35517 (16) | 0.52949 (16) | 0.40449 (9) | 0.0310 (5) | |
C22 | 0.35997 (17) | 0.39047 (17) | 0.38958 (10) | 0.0369 (5) | |
C23 | 0.24583 (17) | 0.31272 (16) | 0.38742 (10) | 0.0349 (5) | |
C24 | 0.12536 (16) | 0.37375 (16) | 0.39988 (9) | 0.0300 (5) | |
C25 | 0.12406 (14) | 0.51209 (15) | 0.41452 (8) | 0.0246 (4) | |
H1 | 0.25670 | 0.68190 | 0.69160 | 0.0360* | |
H3 | 0.18990 | 0.93750 | 0.74660 | 0.0400* | |
H4 | 0.13680 | 1.15540 | 0.70400 | 0.0430* | |
H5 | 0.11920 | 1.20650 | 0.57580 | 0.0410* | |
H6 | 0.15330 | 1.04080 | 0.48570 | 0.0330* | |
H9 | 0.27390 | 0.57650 | 0.56970 | 0.0320* | |
H10 | 0.13910 | 0.77760 | 0.41590 | 0.0260* | |
H12 | 0.50150 | 0.80260 | 0.47320 | 0.0330* | |
H13 | 0.60610 | 0.95990 | 0.39160 | 0.0350* | |
H15 | 0.53040 | 1.11870 | 0.26470 | 0.0350* | |
H16 | 0.34400 | 1.17550 | 0.18650 | 0.0360* | |
H17 | 0.13790 | 1.08520 | 0.20710 | 0.0350* | |
H18 | 0.11390 | 0.92710 | 0.30240 | 0.0290* | |
H21 | 0.43320 | 0.58030 | 0.40580 | 0.0370* | |
H22 | 0.44070 | 0.34960 | 0.38100 | 0.0440* | |
H23 | 0.24960 | 0.21960 | 0.37760 | 0.0420* | |
H24 | 0.04740 | 0.32280 | 0.39840 | 0.0360* |
U11 | U22 | U33 | U12 | U13 | U23 | |
F26 | 0.0230 (4) | 0.0280 (4) | 0.0438 (6) | −0.0020 (3) | 0.0034 (4) | −0.0013 (4) |
N1 | 0.0418 (8) | 0.0289 (7) | 0.0201 (7) | −0.0057 (5) | 0.0031 (6) | 0.0031 (5) |
N13 | 0.0192 (6) | 0.0338 (7) | 0.0345 (8) | −0.0060 (5) | 0.0005 (5) | 0.0060 (6) |
C2 | 0.0235 (7) | 0.0278 (7) | 0.0273 (8) | −0.0067 (6) | 0.0059 (6) | −0.0036 (6) |
C3 | 0.0283 (8) | 0.0424 (9) | 0.0307 (9) | −0.0117 (7) | 0.0099 (7) | −0.0111 (7) |
C4 | 0.0244 (8) | 0.0356 (9) | 0.0487 (11) | −0.0057 (7) | 0.0109 (7) | −0.0194 (8) |
C5 | 0.0216 (7) | 0.0265 (8) | 0.0550 (11) | 0.0008 (6) | 0.0036 (7) | −0.0081 (7) |
C6 | 0.0190 (7) | 0.0257 (7) | 0.0363 (9) | −0.0011 (6) | 0.0000 (6) | −0.0012 (7) |
C7 | 0.0170 (7) | 0.0246 (7) | 0.0266 (8) | −0.0040 (5) | 0.0029 (6) | −0.0025 (6) |
C8 | 0.0196 (7) | 0.0220 (7) | 0.0241 (8) | −0.0039 (5) | 0.0031 (6) | −0.0015 (6) |
C9 | 0.0322 (8) | 0.0218 (7) | 0.0273 (8) | −0.0025 (6) | 0.0045 (6) | −0.0006 (6) |
C10 | 0.0213 (7) | 0.0220 (7) | 0.0226 (8) | −0.0016 (5) | 0.0013 (6) | −0.0002 (6) |
C11 | 0.0232 (7) | 0.0237 (7) | 0.0216 (7) | −0.0018 (6) | 0.0031 (6) | −0.0010 (6) |
C12 | 0.0261 (8) | 0.0305 (8) | 0.0258 (8) | −0.0027 (6) | −0.0011 (6) | 0.0053 (6) |
C14 | 0.0247 (7) | 0.0240 (7) | 0.0243 (8) | 0.0000 (6) | 0.0039 (6) | −0.0020 (6) |
C15 | 0.0298 (8) | 0.0270 (8) | 0.0329 (9) | −0.0012 (6) | 0.0098 (7) | 0.0015 (7) |
C16 | 0.0405 (9) | 0.0243 (7) | 0.0270 (8) | 0.0026 (6) | 0.0076 (7) | 0.0046 (6) |
C17 | 0.0355 (8) | 0.0238 (7) | 0.0279 (8) | 0.0057 (6) | −0.0035 (7) | −0.0013 (6) |
C18 | 0.0251 (7) | 0.0221 (7) | 0.0258 (8) | −0.0002 (6) | 0.0013 (6) | −0.0039 (6) |
C19 | 0.0235 (7) | 0.0205 (7) | 0.0210 (7) | −0.0006 (5) | 0.0044 (6) | −0.0045 (6) |
C20 | 0.0273 (8) | 0.0246 (7) | 0.0177 (7) | −0.0019 (6) | 0.0027 (6) | −0.0009 (6) |
C21 | 0.0290 (8) | 0.0302 (8) | 0.0344 (9) | −0.0023 (6) | 0.0070 (7) | −0.0048 (7) |
C22 | 0.0353 (9) | 0.0331 (8) | 0.0435 (10) | 0.0045 (7) | 0.0114 (8) | −0.0071 (7) |
C23 | 0.0456 (10) | 0.0256 (8) | 0.0342 (9) | −0.0003 (7) | 0.0085 (7) | −0.0066 (7) |
C24 | 0.0341 (8) | 0.0263 (8) | 0.0299 (8) | −0.0072 (6) | 0.0037 (7) | −0.0046 (6) |
C25 | 0.0239 (7) | 0.0285 (8) | 0.0215 (8) | 0.0008 (6) | 0.0024 (6) | −0.0009 (6) |
F26—C25 | 1.3606 (16) | C17—C18 | 1.382 (2) |
N1—C2 | 1.3728 (19) | C18—C19 | 1.405 (2) |
N1—C9 | 1.372 (2) | C20—C25 | 1.389 (2) |
N13—C12 | 1.3739 (19) | C20—C21 | 1.391 (2) |
N13—C14 | 1.3703 (19) | C21—C22 | 1.389 (2) |
N1—H1 | 0.8600 | C22—C23 | 1.378 (2) |
N13—H13 | 0.8600 | C23—C24 | 1.386 (2) |
C2—C3 | 1.397 (2) | C24—C25 | 1.380 (2) |
C2—C7 | 1.410 (2) | C3—H3 | 0.9300 |
C3—C4 | 1.376 (2) | C4—H4 | 0.9300 |
C4—C5 | 1.399 (3) | C5—H5 | 0.9300 |
C5—C6 | 1.382 (2) | C6—H6 | 0.9300 |
C6—C7 | 1.406 (2) | C9—H9 | 0.9300 |
C7—C8 | 1.4426 (19) | C10—H10 | 0.9800 |
C8—C9 | 1.360 (2) | C12—H12 | 0.9300 |
C8—C10 | 1.508 (2) | C15—H15 | 0.9300 |
C10—C11 | 1.511 (2) | C16—H16 | 0.9300 |
C10—C20 | 1.5300 (19) | C17—H17 | 0.9300 |
C11—C12 | 1.364 (2) | C18—H18 | 0.9300 |
C11—C19 | 1.435 (2) | C21—H21 | 0.9300 |
C14—C19 | 1.417 (2) | C22—H22 | 0.9300 |
C14—C15 | 1.396 (2) | C23—H23 | 0.9300 |
C15—C16 | 1.378 (2) | C24—H24 | 0.9300 |
C16—C17 | 1.399 (2) | ||
C2—N1—C9 | 109.10 (12) | C10—C20—C21 | 124.09 (13) |
C12—N13—C14 | 109.23 (12) | C20—C21—C22 | 121.57 (15) |
C2—N1—H1 | 125.00 | C21—C22—C23 | 120.43 (16) |
C9—N1—H1 | 125.00 | C22—C23—C24 | 119.80 (15) |
C12—N13—H13 | 125.00 | C23—C24—C25 | 118.29 (14) |
C14—N13—H13 | 125.00 | F26—C25—C24 | 117.97 (13) |
N1—C2—C7 | 107.22 (13) | C20—C25—C24 | 124.02 (14) |
C3—C2—C7 | 122.18 (14) | F26—C25—C20 | 118.01 (12) |
N1—C2—C3 | 130.58 (15) | C2—C3—H3 | 121.00 |
C2—C3—C4 | 117.34 (16) | C4—C3—H3 | 121.00 |
C3—C4—C5 | 121.64 (16) | C3—C4—H4 | 119.00 |
C4—C5—C6 | 121.24 (15) | C5—C4—H4 | 119.00 |
C5—C6—C7 | 118.55 (15) | C4—C5—H5 | 119.00 |
C2—C7—C8 | 107.18 (12) | C6—C5—H5 | 119.00 |
C6—C7—C8 | 133.75 (13) | C5—C6—H6 | 121.00 |
C2—C7—C6 | 119.05 (13) | C7—C6—H6 | 121.00 |
C9—C8—C10 | 128.64 (13) | N1—C9—H9 | 125.00 |
C7—C8—C9 | 106.08 (13) | C8—C9—H9 | 125.00 |
C7—C8—C10 | 125.28 (12) | C8—C10—H10 | 107.00 |
N1—C9—C8 | 110.41 (13) | C11—C10—H10 | 107.00 |
C8—C10—C20 | 110.13 (11) | C20—C10—H10 | 107.00 |
C11—C10—C20 | 114.02 (12) | N13—C12—H12 | 125.00 |
C8—C10—C11 | 111.58 (11) | C11—C12—H12 | 125.00 |
C10—C11—C12 | 128.07 (13) | C14—C15—H15 | 121.00 |
C10—C11—C19 | 125.60 (12) | C16—C15—H15 | 121.00 |
C12—C11—C19 | 106.33 (13) | C15—C16—H16 | 119.00 |
N13—C12—C11 | 110.15 (13) | C17—C16—H16 | 119.00 |
N13—C14—C15 | 130.82 (14) | C16—C17—H17 | 119.00 |
C15—C14—C19 | 122.07 (13) | C18—C17—H17 | 119.00 |
N13—C14—C19 | 107.10 (12) | C17—C18—H18 | 121.00 |
C14—C15—C16 | 117.73 (14) | C19—C18—H18 | 120.00 |
C15—C16—C17 | 121.30 (14) | C20—C21—H21 | 119.00 |
C16—C17—C18 | 121.22 (14) | C22—C21—H21 | 119.00 |
C17—C18—C19 | 119.02 (13) | C21—C22—H22 | 120.00 |
C14—C19—C18 | 118.60 (13) | C23—C22—H22 | 120.00 |
C11—C19—C14 | 107.16 (12) | C22—C23—H23 | 120.00 |
C11—C19—C18 | 134.18 (13) | C24—C23—H23 | 120.00 |
C10—C20—C25 | 119.96 (12) | C23—C24—H24 | 121.00 |
C21—C20—C25 | 115.88 (13) | C25—C24—H24 | 121.00 |
C9—N1—C2—C3 | −179.64 (15) | C8—C10—C20—C25 | 80.00 (16) |
C9—N1—C2—C7 | −1.13 (16) | C11—C10—C20—C21 | 29.6 (2) |
C2—N1—C9—C8 | 1.08 (17) | C11—C10—C20—C25 | −153.68 (13) |
C14—N13—C12—C11 | 0.86 (17) | C10—C11—C12—N13 | 178.93 (13) |
C12—N13—C14—C15 | 179.23 (15) | C19—C11—C12—N13 | −1.51 (17) |
C12—N13—C14—C19 | 0.18 (16) | C10—C11—C19—C14 | −178.85 (13) |
N1—C2—C3—C4 | 177.56 (15) | C10—C11—C19—C18 | 4.2 (3) |
C7—C2—C3—C4 | −0.8 (2) | C12—C11—C19—C14 | 1.58 (16) |
N1—C2—C7—C6 | −177.98 (12) | C12—C11—C19—C18 | −175.37 (16) |
N1—C2—C7—C8 | 0.77 (15) | N13—C14—C15—C16 | −177.53 (15) |
C3—C2—C7—C6 | 0.7 (2) | C19—C14—C15—C16 | 1.4 (2) |
C3—C2—C7—C8 | 179.44 (13) | N13—C14—C19—C11 | −1.08 (15) |
C2—C3—C4—C5 | 0.3 (2) | N13—C14—C19—C18 | 176.43 (12) |
C3—C4—C5—C6 | 0.2 (2) | C15—C14—C19—C11 | 179.76 (13) |
C4—C5—C6—C7 | −0.3 (2) | C15—C14—C19—C18 | −2.7 (2) |
C5—C6—C7—C2 | −0.2 (2) | C14—C15—C16—C17 | 0.9 (2) |
C5—C6—C7—C8 | −178.49 (15) | C15—C16—C17—C18 | −1.9 (2) |
C2—C7—C8—C9 | −0.14 (15) | C16—C17—C18—C19 | 0.5 (2) |
C2—C7—C8—C10 | −179.35 (13) | C17—C18—C19—C11 | 178.41 (15) |
C6—C7—C8—C9 | 178.35 (15) | C17—C18—C19—C14 | 1.7 (2) |
C6—C7—C8—C10 | −0.9 (2) | C10—C20—C21—C22 | 176.78 (15) |
C7—C8—C9—N1 | −0.56 (16) | C25—C20—C21—C22 | −0.1 (2) |
C10—C8—C9—N1 | 178.62 (13) | C10—C20—C25—F26 | 3.4 (2) |
C7—C8—C10—C11 | 62.75 (17) | C10—C20—C25—C24 | −176.90 (14) |
C7—C8—C10—C20 | −169.58 (12) | C21—C20—C25—F26 | −179.62 (13) |
C9—C8—C10—C11 | −116.29 (16) | C21—C20—C25—C24 | 0.1 (2) |
C9—C8—C10—C20 | 11.4 (2) | C20—C21—C22—C23 | −0.1 (3) |
C8—C10—C11—C12 | 49.0 (2) | C21—C22—C23—C24 | 0.3 (3) |
C8—C10—C11—C19 | −130.47 (14) | C22—C23—C24—C25 | −0.3 (2) |
C20—C10—C11—C12 | −76.54 (19) | C23—C24—C25—F26 | 179.77 (14) |
C20—C10—C11—C19 | 103.98 (16) | C23—C24—C25—C20 | 0.1 (2) |
C8—C10—C20—C21 | −96.71 (16) |
Cg1, Cg2, Cg3 and Cg4 are the centroids of the N1/C2/C7–C9, C2–C7, C14–C19 and C20–C25 rings, respectively. |
D—H···A | D—H | H···A | D···A | D—H···A |
C5—H5···F26i | 0.93 | 2.51 | 3.3849 (18) | 157 |
N1—H1···Cg4ii | 0.86 | 2.63 | 3.4390 (14) | 157 |
N13—H13···Cg3iii | 0.86 | 2.30 | 3.1539 (14) | 170 |
C3—H3···Cg5ii | 0.93 | 2.96 | 3.7630 (19) | 146 |
C23—H23···Cg4iv | 0.93 | 2.68 | 3.5022 (17) | 147 |
C24—H24···Cg1v | 0.93 | 2.93 | 3.8376 (17) | 166 |
Symmetry codes: (i) −x, −y+2, −z+1; (ii) x, −y+3/2, z+1/2; (iii) −x+1, −y+2, −z+1; (iv) x, y−1, z; (v) −x, −y+1, −z+1. |
Acknowledgements
The authors are thankful to the IOE, Vijnana Bhavana, University of Mysore, for providing the single-crystal X-ray diffractometer facility. RAK thanks the UGC, New Delhi, for financial support through a BSR fellowship.
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