organic compounds
4-(Benzofuran-2-yl)-2-[3-(4-chlorophenyl)-5-(4-fluorophenyl)-4,5-dihydro-1H-pyrazol-1-yl]thiazole
aDepartment of Optometry, College of Applied Medical Sciences, King Saud University, PO Box 10219, Riyadh 11433, Saudi Arabia, bDepartment of Chemistry, College of Science and Humanities, Shaqra University, Duwadimi, Saudi Arabia, cApplied Organic Chemistry Department, National Research Centre, Dokki, Giza, Egypt, dPharmaceutical Chemistry Department, College of Pharmacy, Umm Al-Qura University, Makkah, Saudi Arabia, and eSchool of Chemistry, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, Wales
*Correspondence e-mail: gelhiti@ksu.edu.sa, kariukib@cardiff.ac.uk
The molecule of the title compound, C26H17ClFN3OS, comprises benzofuranyl (A), thiazolyl (B), pyrazolyl (C), chlorophenyl (D) and fluorophenyl (E) ring systems. Rings A–D are almost coplanar, as indicated by the twist angles between the ring pairs A/B, B/C and C/D of 7.6 (1), 4.7 (1) and 6.9 (2)°, respectively. Ring E is twisted by 73.2 (1)° from the plane through ring C. In the crystal, pairwise C—H⋯F interactions link the molecules into inversion dimers. Aromatic π–π interactions are also observed between rings A and E and between rings B and C for neighbouring pairs of molecules related by inversion symmetry. Taken together, the weak interactions generate [010] chains.
Keywords: crystal structure; benzofuran; thiazole; pyrazole.
CCDC reference: 1903156
Structure description
Compounds containing a benzofuran moiety are present in many important natural products and drugs (Naik et al., 2015). In addition, thiazoles and pyrazoles are an essential core scaffold in many natural products and have various biological activities (Chhabria et al., 2016; Faria et al., 2017). Therefore, the synthesis, characterization and applications of compounds containing such heterocycles are of continued interest and we describe here the synthesis and structure of the title compound.
The molecule of the title compound comprises benzofuranyl (A), thiazolyl (B), pyrazolyl (C), chlorophenyl (D) and fluorophenyl (E) ring systems (Fig. 1). Rings A–D are almost coplanar, as indicated by the twist angles between the ring pairs A/B, B/C and C/D of 7.6 (1), 4.7 (1) and 6.9 (2)°, respectively. Ring E is twisted by 73.2 (1)° from the plane through ring C. In the arbitrarily-chosen the stereogenic centre C12 has an S configuration, but crystal symmetry generates a racemic mixture.
In the crystal, pairwise C—H⋯F interactions link molecules into inversion dimers (Table 1). Aromatic π–π interactions are also observed between rings A and E [centroid–centroid separation = 3.755 (2) Å] and between rings B and C [3.796 (2) Å] for neighbouring pairs of molecules related by inversion symmetry; this results in each pair of molecules being linked by four π–π interactions (Fig. 2). The combination of C—H⋯F and π–π interactions generates [010] chains.
Synthesis and crystallization
The title compound was synthesized from the condensation of molar equivalents of 3-(4-chlorophenyl)-5-(4-fluorophenyl)-4,5-dihydro-1H-pyrazole-1-carbothioamide with 1-(benzofuran-2-yl)-2-bromoethanone in anhydrous ethanol under reflux for 2 h. The crude product was recrystallized from dimethylformamide solution to give colourless needles (yield 74%, m.p. 234–236 °C).
Refinement
All H atoms were placed in calculated positions and refined using a riding model. Bond lengths were set at 0.98, 0.97 and 0.93 Å for methine, methylene and aromatic C—H H atoms, respectively, with their Uiso(H) values set at 1.2 times the Ueq of the atom to which they are bonded. Crystal data, data collection and structure details are summarized in Table 2.
Structural data
CCDC reference: 1903156
https://doi.org/10.1107/S2414314619003596/hb4289sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314619003596/hb4289Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2414314619003596/hb4289Isup3.cml
Data collection: CrysAlis PRO (Rigaku OD, 2015); cell
CrysAlis PRO (Rigaku OD, 2015); data reduction: CrysAlis PRO (Rigaku OD, 2015); program(s) used to solve structure: SHELXS (Sheldrick, 2008); program(s) used to refine structure: SHELXL2018 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows and WinGX (Farrugia, 2012); software used to prepare material for publication: ORTEP-3 for Windows and WinGX (Farrugia, 2012), and CHEMDRAW Ultra (Cambridge Soft, 2001).C26H17ClFN3OS | F(000) = 976 |
Mr = 473.93 | Dx = 1.392 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 6.6631 (6) Å | Cell parameters from 1999 reflections |
b = 15.2297 (17) Å | θ = 3.7–23.3° |
c = 22.431 (3) Å | µ = 0.29 mm−1 |
β = 96.390 (9)° | T = 296 K |
V = 2262.1 (4) Å3 | Needle, colourless |
Z = 4 | 0.46 × 0.19 × 0.11 mm |
Rigaku OD SuperNova Dual source diffractometer with an Atlas detector | 2323 reflections with I > 2σ(I) |
ω scans | Rint = 0.042 |
Absorption correction: gaussian (CrysAlis PRO; Rigaku OD, 2015) | θmax = 26.4°, θmin = 3.4° |
Tmin = 0.990, Tmax = 0.997 | h = −6→8 |
10799 measured reflections | k = −19→17 |
4617 independent reflections | l = −28→22 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.060 | H-atom parameters constrained |
wR(F2) = 0.171 | w = 1/[σ2(Fo2) + (0.0542P)2 + 0.6825P] where P = (Fo2 + 2Fc2)/3 |
S = 1.03 | (Δ/σ)max < 0.001 |
4617 reflections | Δρmax = 0.17 e Å−3 |
298 parameters | Δρmin = −0.21 e Å−3 |
0 restraints |
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. |
x | y | z | Uiso*/Ueq | ||
C1 | −0.0420 (5) | 0.9153 (2) | 0.16557 (14) | 0.0617 (8) | |
C2 | −0.2264 (5) | 0.8840 (2) | 0.17209 (15) | 0.0666 (9) | |
H2 | −0.315276 | 0.858931 | 0.141930 | 0.080* | |
C3 | −0.2636 (5) | 0.8956 (2) | 0.23330 (15) | 0.0659 (9) | |
C4 | −0.0873 (5) | 0.9353 (2) | 0.26072 (16) | 0.0669 (9) | |
C5 | −0.4193 (6) | 0.8785 (3) | 0.26796 (18) | 0.0805 (11) | |
H5 | −0.538290 | 0.852152 | 0.251208 | 0.097* | |
C6 | −0.3937 (7) | 0.9014 (3) | 0.32729 (19) | 0.0923 (12) | |
H6 | −0.497815 | 0.891053 | 0.350794 | 0.111* | |
C7 | −0.2172 (8) | 0.9393 (3) | 0.35304 (18) | 0.0948 (13) | |
H7 | −0.204363 | 0.952927 | 0.393693 | 0.114* | |
C8 | −0.0587 (7) | 0.9576 (3) | 0.32022 (18) | 0.0898 (12) | |
H8 | 0.060249 | 0.983506 | 0.337468 | 0.108* | |
C9 | 0.0725 (5) | 0.9187 (2) | 0.11473 (14) | 0.0591 (8) | |
C10 | 0.2685 (5) | 0.9408 (2) | 0.11469 (16) | 0.0712 (10) | |
H10 | 0.351786 | 0.959633 | 0.148300 | 0.085* | |
C11 | 0.1001 (5) | 0.8959 (2) | 0.01989 (16) | 0.0637 (8) | |
C12 | −0.1510 (5) | 0.8293 (2) | −0.05800 (15) | 0.0661 (9) | |
H12 | −0.261981 | 0.869744 | −0.052668 | 0.079* | |
C13 | −0.1304 (5) | 0.8178 (3) | −0.12471 (15) | 0.0810 (11) | |
H13A | −0.154473 | 0.757287 | −0.137032 | 0.097* | |
H13B | −0.224552 | 0.855387 | −0.148931 | 0.097* | |
C14 | 0.0830 (5) | 0.8439 (2) | −0.13025 (15) | 0.0601 (8) | |
C15 | −0.1805 (5) | 0.7438 (2) | −0.02572 (14) | 0.0602 (8) | |
C16 | −0.0221 (6) | 0.6941 (3) | 0.00002 (18) | 0.0819 (11) | |
H16 | 0.109071 | 0.713957 | −0.001787 | 0.098* | |
C17 | −0.0516 (6) | 0.6161 (3) | 0.02832 (19) | 0.0900 (12) | |
H17 | 0.057272 | 0.583478 | 0.045913 | 0.108* | |
C18 | −0.2429 (8) | 0.5880 (3) | 0.02992 (16) | 0.0842 (12) | |
C19 | −0.4061 (6) | 0.6335 (3) | 0.00476 (17) | 0.0840 (12) | |
H19 | −0.536128 | 0.611895 | 0.005850 | 0.101* | |
C20 | −0.3735 (5) | 0.7132 (3) | −0.02265 (15) | 0.0706 (10) | |
H20 | −0.483302 | 0.746331 | −0.039096 | 0.085* | |
C21 | 0.1776 (5) | 0.8416 (2) | −0.18589 (14) | 0.0599 (8) | |
C22 | 0.0785 (6) | 0.8020 (2) | −0.23703 (17) | 0.0777 (10) | |
H22 | −0.047482 | 0.776451 | −0.235296 | 0.093* | |
C23 | 0.1650 (7) | 0.8002 (3) | −0.29021 (18) | 0.0883 (12) | |
H23 | 0.097113 | 0.774069 | −0.324130 | 0.106* | |
C24 | 0.3519 (6) | 0.8371 (3) | −0.29268 (17) | 0.0790 (11) | |
C25 | 0.4505 (5) | 0.8776 (3) | −0.24365 (18) | 0.0794 (11) | |
H25 | 0.575572 | 0.903742 | −0.245998 | 0.095* | |
C26 | 0.3637 (5) | 0.8797 (2) | −0.19036 (16) | 0.0706 (9) | |
H26 | 0.431759 | 0.907147 | −0.157005 | 0.085* | |
N1 | −0.0258 (4) | 0.89273 (19) | 0.06012 (12) | 0.0645 (7) | |
N3 | 0.0437 (4) | 0.8709 (2) | −0.03768 (13) | 0.0748 (8) | |
N4 | 0.1770 (4) | 0.87408 (18) | −0.08051 (12) | 0.0629 (7) | |
O1 | 0.0500 (3) | 0.94806 (16) | 0.21956 (10) | 0.0709 (6) | |
Cl1 | 0.4626 (2) | 0.83256 (9) | −0.35884 (5) | 0.1214 (5) | |
F1 | −0.2761 (5) | 0.51028 (17) | 0.05775 (12) | 0.1259 (10) | |
S1 | 0.34414 (13) | 0.92974 (7) | 0.04410 (4) | 0.0766 (3) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.063 (2) | 0.063 (2) | 0.056 (2) | 0.0041 (17) | −0.0049 (16) | −0.0023 (16) |
C2 | 0.066 (2) | 0.071 (2) | 0.060 (2) | 0.0049 (18) | −0.0033 (17) | −0.0044 (17) |
C3 | 0.071 (2) | 0.062 (2) | 0.062 (2) | 0.0090 (18) | −0.0027 (18) | 0.0024 (17) |
C4 | 0.075 (2) | 0.065 (2) | 0.059 (2) | 0.0109 (18) | −0.0007 (18) | 0.0038 (17) |
C5 | 0.085 (3) | 0.084 (3) | 0.072 (3) | 0.000 (2) | 0.008 (2) | 0.009 (2) |
C6 | 0.115 (3) | 0.093 (3) | 0.071 (3) | 0.009 (3) | 0.019 (3) | 0.016 (2) |
C7 | 0.132 (4) | 0.093 (3) | 0.058 (2) | 0.006 (3) | 0.009 (3) | 0.002 (2) |
C8 | 0.110 (3) | 0.093 (3) | 0.063 (3) | −0.003 (3) | −0.006 (2) | −0.007 (2) |
C9 | 0.0597 (18) | 0.059 (2) | 0.057 (2) | 0.0007 (16) | 0.0008 (16) | 0.0016 (16) |
C10 | 0.068 (2) | 0.077 (2) | 0.067 (2) | −0.0116 (19) | 0.0042 (17) | −0.0081 (18) |
C11 | 0.070 (2) | 0.058 (2) | 0.063 (2) | −0.0065 (17) | 0.0039 (18) | 0.0037 (17) |
C12 | 0.0570 (18) | 0.077 (2) | 0.063 (2) | −0.0064 (18) | 0.0009 (16) | −0.0006 (18) |
C13 | 0.072 (2) | 0.109 (3) | 0.061 (2) | −0.021 (2) | 0.0003 (18) | 0.009 (2) |
C14 | 0.0591 (18) | 0.056 (2) | 0.063 (2) | −0.0051 (16) | −0.0002 (16) | 0.0059 (16) |
C15 | 0.0571 (18) | 0.072 (2) | 0.0513 (19) | −0.0030 (18) | 0.0052 (15) | −0.0078 (16) |
C16 | 0.067 (2) | 0.081 (3) | 0.096 (3) | −0.007 (2) | 0.001 (2) | 0.005 (2) |
C17 | 0.090 (3) | 0.078 (3) | 0.098 (3) | 0.000 (2) | −0.010 (2) | 0.002 (2) |
C18 | 0.122 (4) | 0.073 (3) | 0.057 (2) | −0.016 (3) | 0.004 (2) | 0.0010 (19) |
C19 | 0.082 (3) | 0.098 (3) | 0.075 (3) | −0.027 (2) | 0.023 (2) | −0.009 (2) |
C20 | 0.061 (2) | 0.086 (3) | 0.065 (2) | −0.005 (2) | 0.0091 (17) | −0.0046 (19) |
C21 | 0.068 (2) | 0.0521 (19) | 0.058 (2) | −0.0010 (16) | 0.0029 (16) | 0.0048 (16) |
C22 | 0.088 (3) | 0.073 (2) | 0.071 (3) | −0.016 (2) | 0.004 (2) | 0.000 (2) |
C23 | 0.116 (3) | 0.083 (3) | 0.064 (3) | −0.006 (3) | 0.002 (2) | −0.006 (2) |
C24 | 0.099 (3) | 0.075 (3) | 0.064 (2) | 0.013 (2) | 0.016 (2) | 0.008 (2) |
C25 | 0.071 (2) | 0.096 (3) | 0.072 (3) | 0.003 (2) | 0.012 (2) | 0.013 (2) |
C26 | 0.068 (2) | 0.077 (2) | 0.067 (2) | −0.0017 (19) | 0.0035 (18) | 0.0026 (18) |
N1 | 0.0649 (16) | 0.0714 (19) | 0.0562 (17) | −0.0042 (14) | 0.0018 (14) | −0.0032 (14) |
N3 | 0.0708 (18) | 0.095 (2) | 0.0586 (18) | −0.0241 (16) | 0.0089 (15) | −0.0044 (16) |
N4 | 0.0627 (16) | 0.0638 (18) | 0.0622 (18) | −0.0054 (14) | 0.0064 (14) | −0.0006 (14) |
O1 | 0.0718 (14) | 0.0755 (16) | 0.0627 (15) | −0.0045 (12) | −0.0045 (12) | −0.0076 (12) |
Cl1 | 0.1498 (11) | 0.1418 (12) | 0.0796 (8) | 0.0282 (9) | 0.0433 (7) | 0.0075 (7) |
F1 | 0.176 (3) | 0.0949 (19) | 0.105 (2) | −0.0308 (18) | 0.0060 (17) | 0.0190 (15) |
S1 | 0.0685 (6) | 0.0863 (7) | 0.0745 (6) | −0.0181 (5) | 0.0061 (5) | −0.0031 (5) |
C1—C2 | 1.341 (4) | C13—H13A | 0.9700 |
C1—O1 | 1.388 (4) | C13—H13B | 0.9700 |
C1—C9 | 1.442 (4) | C14—N4 | 1.301 (4) |
C2—C3 | 1.433 (4) | C14—C21 | 1.460 (4) |
C2—H2 | 0.9300 | C15—C16 | 1.372 (5) |
C3—C5 | 1.389 (5) | C15—C20 | 1.377 (4) |
C3—C4 | 1.401 (5) | C16—C17 | 1.372 (5) |
C4—C8 | 1.370 (5) | C16—H16 | 0.9300 |
C4—O1 | 1.384 (4) | C17—C18 | 1.349 (5) |
C5—C6 | 1.368 (5) | C17—H17 | 0.9300 |
C5—H5 | 0.9300 | C18—C19 | 1.358 (5) |
C6—C7 | 1.378 (6) | C18—F1 | 1.367 (4) |
C6—H6 | 0.9300 | C19—C20 | 1.389 (5) |
C7—C8 | 1.381 (6) | C19—H19 | 0.9300 |
C7—H7 | 0.9300 | C20—H20 | 0.9300 |
C8—H8 | 0.9300 | C21—C26 | 1.383 (4) |
C9—C10 | 1.350 (4) | C21—C22 | 1.396 (5) |
C9—N1 | 1.381 (4) | C22—C23 | 1.382 (5) |
C10—S1 | 1.722 (4) | C22—H22 | 0.9300 |
C10—H10 | 0.9300 | C23—C24 | 1.373 (5) |
C11—N1 | 1.300 (4) | C23—H23 | 0.9300 |
C11—N3 | 1.359 (4) | C24—C25 | 1.365 (5) |
C11—S1 | 1.734 (3) | C24—Cl1 | 1.731 (4) |
C12—N3 | 1.470 (4) | C25—C26 | 1.385 (5) |
C12—C15 | 1.513 (5) | C25—H25 | 0.9300 |
C12—C13 | 1.528 (5) | C26—H26 | 0.9300 |
C12—H12 | 0.9800 | N3—N4 | 1.380 (3) |
C13—C14 | 1.495 (4) | ||
C2—C1—O1 | 110.7 (3) | N4—C14—C13 | 113.2 (3) |
C2—C1—C9 | 132.1 (3) | C21—C14—C13 | 124.7 (3) |
O1—C1—C9 | 117.1 (3) | C16—C15—C20 | 118.1 (3) |
C1—C2—C3 | 108.6 (3) | C16—C15—C12 | 122.7 (3) |
C1—C2—H2 | 125.7 | C20—C15—C12 | 119.1 (3) |
C3—C2—H2 | 125.7 | C17—C16—C15 | 121.9 (4) |
C5—C3—C4 | 118.5 (3) | C17—C16—H16 | 119.0 |
C5—C3—C2 | 137.1 (4) | C15—C16—H16 | 119.0 |
C4—C3—C2 | 104.4 (3) | C18—C17—C16 | 118.1 (4) |
C8—C4—O1 | 125.8 (4) | C18—C17—H17 | 120.9 |
C8—C4—C3 | 123.6 (4) | C16—C17—H17 | 120.9 |
O1—C4—C3 | 110.6 (3) | C17—C18—C19 | 122.8 (4) |
C6—C5—C3 | 118.5 (4) | C17—C18—F1 | 119.2 (4) |
C6—C5—H5 | 120.7 | C19—C18—F1 | 118.0 (4) |
C3—C5—H5 | 120.7 | C18—C19—C20 | 118.3 (4) |
C5—C6—C7 | 121.5 (4) | C18—C19—H19 | 120.9 |
C5—C6—H6 | 119.3 | C20—C19—H19 | 120.9 |
C7—C6—H6 | 119.3 | C15—C20—C19 | 120.7 (4) |
C6—C7—C8 | 121.9 (4) | C15—C20—H20 | 119.7 |
C6—C7—H7 | 119.0 | C19—C20—H20 | 119.7 |
C8—C7—H7 | 119.0 | C26—C21—C22 | 117.9 (3) |
C4—C8—C7 | 115.9 (4) | C26—C21—C14 | 121.9 (3) |
C4—C8—H8 | 122.0 | C22—C21—C14 | 120.2 (3) |
C7—C8—H8 | 122.0 | C23—C22—C21 | 120.9 (3) |
C10—C9—N1 | 115.8 (3) | C23—C22—H22 | 119.5 |
C10—C9—C1 | 127.4 (3) | C21—C22—H22 | 119.5 |
N1—C9—C1 | 116.8 (3) | C24—C23—C22 | 119.6 (4) |
C9—C10—S1 | 111.0 (3) | C24—C23—H23 | 120.2 |
C9—C10—H10 | 124.5 | C22—C23—H23 | 120.2 |
S1—C10—H10 | 124.5 | C25—C24—C23 | 120.7 (3) |
N1—C11—N3 | 121.2 (3) | C25—C24—Cl1 | 119.7 (3) |
N1—C11—S1 | 116.7 (3) | C23—C24—Cl1 | 119.6 (3) |
N3—C11—S1 | 122.1 (3) | C24—C25—C26 | 119.7 (4) |
N3—C12—C15 | 112.3 (3) | C24—C25—H25 | 120.1 |
N3—C12—C13 | 100.4 (3) | C26—C25—H25 | 120.1 |
C15—C12—C13 | 113.6 (3) | C21—C26—C25 | 121.2 (3) |
N3—C12—H12 | 110.1 | C21—C26—H26 | 119.4 |
C15—C12—H12 | 110.1 | C25—C26—H26 | 119.4 |
C13—C12—H12 | 110.1 | C11—N1—C9 | 109.0 (3) |
C14—C13—C12 | 103.9 (3) | C11—N3—N4 | 121.3 (3) |
C14—C13—H13A | 111.0 | C11—N3—C12 | 123.9 (3) |
C12—C13—H13A | 111.0 | N4—N3—C12 | 114.4 (3) |
C14—C13—H13B | 111.0 | C14—N4—N3 | 107.4 (3) |
C12—C13—H13B | 111.0 | C4—O1—C1 | 105.7 (3) |
H13A—C13—H13B | 109.0 | C10—S1—C11 | 87.54 (17) |
N4—C14—C21 | 122.0 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
C19—H19···F1i | 0.93 | 2.58 | 3.254 (5) | 130 |
Symmetry code: (i) −x−1, −y+1, −z. |
Acknowledgements
The authors thank Umm Al-Qura and Cardiff Universities for their ongoing support.
Funding information
Funding for this research was provided by: Deanship of Scientific Research at Umm Al-Qura University (grant No. 17-MED-1-03-0007 to AA).
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