organic compounds
1-[5-(3,5-Dimethoxyphenyl)-3-(2-methoxyphenyl)-4,5-dihydro-1H-pyrazol-1-yl]ethanone
aDepartment of Applied Chemistry, Dongduk Women's University, Seoul 136-714, Republic of Korea
*Correspondence e-mail: dskoh@dongduk.ac.kr
In the title compound, C20H22N2O4, two benzene rings bearing methoxy substituents are connected by a central acetylpyrazoline ring: the dihedral angle between the benzene rings is 83.7 (1)°. In the crystal, pairwise C—H⋯O hydrogen bonds generate inversion dimers and additional weak C—H⋯O interactions link the dimers into chains propagating along the c-axis direction.
Keywords: crystal structure; pyrazolines; C—H⋯O hydrogen bonds.
CCDC reference: 2058998
Structure description
Pyrazolines show a broad spectrum of biological activities including anticancer (Matiadis & Sagnou, 2020), Alzheimer drugs (Neudorfer et al., 2014) and the dual function of antimalarial and antimicrobial activities (Mishra, et al., 2017). According to a recent review, pyrazolines have also demonstrated versatile applications in bio-imaging and sensing (Varghese et al., 2017). In a continuation of our studies of pyrazolines that show a broad range of biological activities (Jung et al. 2015), the title compound was synthesized and its was determined.
The molecular structure of the title compound is shown in Fig. 1. Atom C10 has an S configuration in the arbitrarily chosen but crystal symmetry generates a The central pyrazoline ring (N1/N2/C8–C10) connects the two benzene rings (C1–C6 and C11–C16) at carbon atoms 8 and 10, respectively. The dihedral angle between the pyrazoline ring and the C1–C6 benzene ring is 6.25 (2)°, indicating that the rings are close to coplanar. On the other hand, the dihedral angle formed by the pyrazoline ring and the C11–C16 benzene ring is 83.9 (3)°, which indicates that these two rings are almost orthogonal to each other. The dihedral angle between the benzene rings is 83.7 (1)°. There are three methoxy groups, which are attached to carbon-atom C1 of the first benzene ring and C13 and C15 of the second. The C18 atom of the methoxy group at C15 is essentially co-planar with the benzene ring [C18—O3—C15—C16 = 0.5 (2)°], whereas the C7 and C17 atoms of the methoxy groups at C1 and C13 are slightly twisted from the corresponding ring plane with torsion angles C6—C1—O1—C7 = 6.1 (2)° and C14—C13—O2—C17 = −2.7 (3)°, respectively. The acetyl group attached to the pyrazoline ring lies in almost the same plane as the ring [C20—C19—N1—N2 = 0.9 (2)°].
In the crystal, pairs of C10—H10⋯O4 hydrogen bonds generate inversion dimers (Table 1, Fig. 2) featuring R22(10) loops and another pair of C—H⋯O hydrogen bonds links the dimers into chains propagating along the c-axis direction (Fig. 3).
Synthesis and crystallization
To a solution of 2-methoxyacetophenone (600 mg, 4 mmol) in 50 ml of ethanol was added 3,5-dimethoxybenzaldehyde (830 mg, 5 mmol) and the temperature was adjusted to around 277 K in an ice-bath. To the cooled reaction mixture were added 5 ml of 40% aqueous KOH solution, and the reaction mixture was stirred at room temperature for 5 h. This mixture was poured into iced water (100 ml) and was acidified (pH = 3) with 2 N HCl solution to give a precipitate. Filtration and washing with water afforded a crude solid of a chalcone compound, which was recrystallized from ethanol solution. To a solution of the chalcone compound (2 mmol, 596 mg) in 20 ml of anhydrous ethanol was added excess hydrazine monohydrate (0.6 ml of 64–65% solution, 7 mmol) and the solution was refluxed at 362 K for 3 h. The reaction mixture was cooled to room temperature to produce a solid. This solid was recrystallized from an ethanol solution to obtain single crystals of the title compound (m.p. 436–437 K, yield; 62%).
Refinement
Crystal data, data collection and structure .
details are summarized in Table 2Structural data
CCDC reference: 2058998
https://doi.org/10.1107/S2414314621000961/hb4374sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314621000961/hb4374Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2414314621000961/hb4374Isup3.cml
Data collection: APEX2 (Bruker, 2012); cell
SAINT (Bruker, 2012); data reduction: SAINT (Bruker, 2012); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014/7 (Sheldrick, 2015); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).C20H22N2O4 | Z = 2 |
Mr = 354.39 | F(000) = 376 |
Triclinic, P1 | Dx = 1.296 Mg m−3 |
a = 8.7181 (2) Å | Mo Kα radiation, λ = 0.71073 Å |
b = 10.7230 (3) Å | Cell parameters from 9964 reflections |
c = 11.2096 (3) Å | θ = 2.3–28.3° |
α = 113.0348 (10)° | µ = 0.09 mm−1 |
β = 91.4395 (12)° | T = 223 K |
γ = 107.4022 (11)° | Block, colourless |
V = 908.09 (4) Å3 | 0.17 × 0.16 × 0.12 mm |
PHOTON 100 CMOS diffractometer | 3338 reflections with I > 2σ(I) |
φ and ω scans | Rint = 0.045 |
Absorption correction: multi-scan (SADABS; Bruker, 2012) | θmax = 28.4°, θmin = 2.2° |
Tmin = 0.643, Tmax = 0.746 | h = −11→11 |
39068 measured reflections | k = −14→14 |
4541 independent reflections | l = −14→14 |
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)] = 0.046 | H-atom parameters constrained |
wR(F2) = 0.126 | w = 1/[σ2(Fo2) + (0.050P)2 + 0.3528P] where P = (Fo2 + 2Fc2)/3 |
S = 1.05 | (Δ/σ)max < 0.001 |
4541 reflections | Δρmax = 0.31 e Å−3 |
239 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 | 0.33313 (18) | 0.31123 (16) | 0.49923 (14) | 0.0328 (3) | |
C2 | 0.28231 (17) | 0.40413 (15) | 0.46044 (13) | 0.0290 (3) | |
C3 | 0.20042 (19) | 0.48741 (17) | 0.54478 (14) | 0.0349 (3) | |
H3 | 0.1650 | 0.5503 | 0.5209 | 0.042* | |
C4 | 0.1704 (2) | 0.47940 (19) | 0.66259 (16) | 0.0423 (4) | |
H4 | 0.1143 | 0.5357 | 0.7174 | 0.051* | |
C5 | 0.2233 (2) | 0.38832 (19) | 0.69949 (16) | 0.0439 (4) | |
H5 | 0.2041 | 0.3837 | 0.7800 | 0.053* | |
C6 | 0.3037 (2) | 0.30458 (18) | 0.61869 (15) | 0.0391 (4) | |
H6 | 0.3390 | 0.2426 | 0.6441 | 0.047* | |
O1 | 0.41126 (15) | 0.23045 (13) | 0.41477 (11) | 0.0445 (3) | |
C7 | 0.4509 (3) | 0.1255 (2) | 0.4431 (2) | 0.0658 (6) | |
H7A | 0.5253 | 0.1720 | 0.5256 | 0.099* | |
H7B | 0.5023 | 0.0745 | 0.3733 | 0.099* | |
H7C | 0.3525 | 0.0580 | 0.4498 | 0.099* | |
C8 | 0.30805 (17) | 0.41521 (15) | 0.33494 (13) | 0.0274 (3) | |
C9 | 0.38469 (18) | 0.32990 (16) | 0.22753 (13) | 0.0304 (3) | |
H9A | 0.3314 | 0.2262 | 0.1994 | 0.037* | |
H9B | 0.5013 | 0.3553 | 0.2562 | 0.037* | |
C10 | 0.35565 (17) | 0.37553 (15) | 0.11689 (13) | 0.0285 (3) | |
H10 | 0.4592 | 0.4092 | 0.0863 | 0.034* | |
N1 | 0.29693 (15) | 0.49645 (12) | 0.18619 (11) | 0.0297 (3) | |
N2 | 0.26272 (15) | 0.50766 (13) | 0.31007 (11) | 0.0298 (3) | |
C11 | 0.22958 (17) | 0.25555 (14) | 0.00294 (13) | 0.0277 (3) | |
C12 | 0.27974 (18) | 0.17696 (15) | −0.10909 (14) | 0.0304 (3) | |
H12 | 0.3907 | 0.2019 | −0.1172 | 0.036* | |
C13 | 0.16453 (19) | 0.06023 (16) | −0.21028 (14) | 0.0339 (3) | |
C14 | 0.00146 (19) | 0.02227 (16) | −0.20007 (15) | 0.0358 (3) | |
H14 | −0.0754 | −0.0568 | −0.2686 | 0.043* | |
C15 | −0.04762 (18) | 0.10307 (15) | −0.08643 (15) | 0.0325 (3) | |
C16 | 0.06497 (18) | 0.21904 (15) | 0.01496 (14) | 0.0312 (3) | |
H16 | 0.0309 | 0.2729 | 0.0914 | 0.037* | |
O2 | 0.22721 (16) | −0.01188 (13) | −0.31699 (11) | 0.0514 (3) | |
C17 | 0.1152 (3) | −0.1365 (3) | −0.4194 (2) | 0.0962 (10) | |
H17A | 0.0575 | −0.2030 | −0.3836 | 0.144* | |
H17B | 0.1739 | −0.1825 | −0.4857 | 0.144* | |
H17C | 0.0378 | −0.1091 | −0.4586 | 0.144* | |
O3 | −0.21162 (13) | 0.05856 (12) | −0.08562 (12) | 0.0446 (3) | |
C18 | −0.2693 (2) | 0.1386 (2) | 0.0275 (2) | 0.0499 (4) | |
H18A | −0.2214 | 0.1346 | 0.1043 | 0.075* | |
H18B | −0.3870 | 0.0978 | 0.0156 | 0.075* | |
H18C | −0.2387 | 0.2380 | 0.0394 | 0.075* | |
C19 | 0.26834 (19) | 0.58262 (16) | 0.13306 (14) | 0.0332 (3) | |
O4 | 0.29910 (15) | 0.56660 (13) | 0.02318 (11) | 0.0439 (3) | |
C20 | 0.1993 (3) | 0.6953 (2) | 0.21300 (18) | 0.0534 (5) | |
H20A | 0.2756 | 0.7898 | 0.2308 | 0.080* | |
H20B | 0.1805 | 0.6879 | 0.2953 | 0.080* | |
H20C | 0.0971 | 0.6813 | 0.1647 | 0.080* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0332 (8) | 0.0326 (7) | 0.0298 (7) | 0.0082 (6) | 0.0000 (6) | 0.0126 (6) |
C2 | 0.0282 (7) | 0.0294 (7) | 0.0249 (7) | 0.0047 (6) | 0.0007 (5) | 0.0106 (6) |
C3 | 0.0377 (8) | 0.0367 (8) | 0.0295 (7) | 0.0119 (7) | 0.0055 (6) | 0.0134 (6) |
C4 | 0.0450 (9) | 0.0474 (9) | 0.0305 (8) | 0.0142 (8) | 0.0106 (7) | 0.0130 (7) |
C5 | 0.0472 (10) | 0.0525 (10) | 0.0286 (8) | 0.0071 (8) | 0.0045 (7) | 0.0209 (7) |
C6 | 0.0423 (9) | 0.0426 (9) | 0.0341 (8) | 0.0087 (7) | −0.0006 (7) | 0.0222 (7) |
O1 | 0.0607 (8) | 0.0464 (7) | 0.0405 (6) | 0.0301 (6) | 0.0114 (6) | 0.0233 (5) |
C7 | 0.0888 (16) | 0.0660 (13) | 0.0723 (14) | 0.0512 (13) | 0.0194 (12) | 0.0398 (12) |
C8 | 0.0274 (7) | 0.0261 (7) | 0.0240 (6) | 0.0057 (5) | 0.0009 (5) | 0.0083 (5) |
C9 | 0.0329 (7) | 0.0315 (7) | 0.0267 (7) | 0.0121 (6) | 0.0036 (6) | 0.0110 (6) |
C10 | 0.0314 (7) | 0.0281 (7) | 0.0246 (7) | 0.0100 (6) | 0.0060 (6) | 0.0095 (6) |
N1 | 0.0396 (7) | 0.0269 (6) | 0.0228 (6) | 0.0113 (5) | 0.0067 (5) | 0.0104 (5) |
N2 | 0.0375 (7) | 0.0291 (6) | 0.0229 (6) | 0.0112 (5) | 0.0062 (5) | 0.0109 (5) |
C11 | 0.0334 (7) | 0.0258 (7) | 0.0256 (7) | 0.0097 (6) | 0.0042 (6) | 0.0126 (6) |
C12 | 0.0330 (7) | 0.0290 (7) | 0.0279 (7) | 0.0088 (6) | 0.0060 (6) | 0.0118 (6) |
C13 | 0.0429 (9) | 0.0284 (7) | 0.0270 (7) | 0.0105 (6) | 0.0058 (6) | 0.0093 (6) |
C14 | 0.0397 (8) | 0.0266 (7) | 0.0341 (8) | 0.0055 (6) | −0.0026 (6) | 0.0105 (6) |
C15 | 0.0310 (7) | 0.0285 (7) | 0.0403 (8) | 0.0074 (6) | 0.0028 (6) | 0.0187 (6) |
C16 | 0.0339 (8) | 0.0306 (7) | 0.0303 (7) | 0.0117 (6) | 0.0073 (6) | 0.0132 (6) |
O2 | 0.0524 (7) | 0.0409 (7) | 0.0345 (6) | 0.0056 (6) | 0.0106 (5) | −0.0036 (5) |
C17 | 0.0702 (16) | 0.0801 (17) | 0.0559 (14) | −0.0046 (13) | 0.0155 (12) | −0.0327 (12) |
O3 | 0.0308 (6) | 0.0366 (6) | 0.0593 (8) | 0.0054 (5) | 0.0046 (5) | 0.0176 (6) |
C18 | 0.0377 (9) | 0.0509 (10) | 0.0661 (12) | 0.0142 (8) | 0.0189 (9) | 0.0296 (10) |
C19 | 0.0402 (8) | 0.0308 (7) | 0.0293 (7) | 0.0099 (6) | 0.0061 (6) | 0.0148 (6) |
O4 | 0.0623 (8) | 0.0473 (7) | 0.0328 (6) | 0.0228 (6) | 0.0169 (5) | 0.0239 (5) |
C20 | 0.0868 (15) | 0.0509 (11) | 0.0473 (10) | 0.0421 (11) | 0.0271 (10) | 0.0305 (9) |
C1—O1 | 1.3617 (18) | N1—N2 | 1.3940 (15) |
C1—C6 | 1.395 (2) | C11—C12 | 1.3778 (19) |
C1—C2 | 1.404 (2) | C11—C16 | 1.395 (2) |
C2—C3 | 1.398 (2) | C12—C13 | 1.394 (2) |
C2—C8 | 1.4746 (19) | C12—H12 | 0.9400 |
C3—C4 | 1.383 (2) | C13—O2 | 1.3744 (18) |
C3—H3 | 0.9400 | C13—C14 | 1.378 (2) |
C4—C5 | 1.383 (2) | C14—C15 | 1.394 (2) |
C4—H4 | 0.9400 | C14—H14 | 0.9400 |
C5—C6 | 1.375 (2) | C15—O3 | 1.3668 (18) |
C5—H5 | 0.9400 | C15—C16 | 1.382 (2) |
C6—H6 | 0.9400 | C16—H16 | 0.9400 |
O1—C7 | 1.412 (2) | O2—C17 | 1.421 (2) |
C7—H7A | 0.9700 | C17—H17A | 0.9700 |
C7—H7B | 0.9700 | C17—H17B | 0.9700 |
C7—H7C | 0.9700 | C17—H17C | 0.9700 |
C8—N2 | 1.2891 (18) | O3—C18 | 1.427 (2) |
C8—C9 | 1.5090 (19) | C18—H18A | 0.9700 |
C9—C10 | 1.5411 (19) | C18—H18B | 0.9700 |
C9—H9A | 0.9800 | C18—H18C | 0.9700 |
C9—H9B | 0.9800 | C19—O4 | 1.2236 (17) |
C10—N1 | 1.4749 (17) | C19—C20 | 1.497 (2) |
C10—C11 | 1.5141 (19) | C20—H20A | 0.9700 |
C10—H10 | 0.9900 | C20—H20B | 0.9700 |
N1—C19 | 1.3534 (19) | C20—H20C | 0.9700 |
O1—C1—C6 | 123.01 (14) | C8—N2—N1 | 108.20 (11) |
O1—C1—C2 | 116.47 (13) | C12—C11—C16 | 120.38 (13) |
C6—C1—C2 | 120.52 (14) | C12—C11—C10 | 119.43 (12) |
C3—C2—C1 | 117.68 (13) | C16—C11—C10 | 120.06 (12) |
C3—C2—C8 | 119.07 (13) | C11—C12—C13 | 119.39 (14) |
C1—C2—C8 | 123.24 (13) | C11—C12—H12 | 120.3 |
C4—C3—C2 | 121.49 (15) | C13—C12—H12 | 120.3 |
C4—C3—H3 | 119.3 | O2—C13—C14 | 124.09 (14) |
C2—C3—H3 | 119.3 | O2—C13—C12 | 114.83 (14) |
C3—C4—C5 | 119.82 (15) | C14—C13—C12 | 121.07 (14) |
C3—C4—H4 | 120.1 | C13—C14—C15 | 118.92 (14) |
C5—C4—H4 | 120.1 | C13—C14—H14 | 120.5 |
C6—C5—C4 | 120.19 (14) | C15—C14—H14 | 120.5 |
C6—C5—H5 | 119.9 | O3—C15—C16 | 124.38 (14) |
C4—C5—H5 | 119.9 | O3—C15—C14 | 114.83 (13) |
C5—C6—C1 | 120.29 (15) | C16—C15—C14 | 120.79 (14) |
C5—C6—H6 | 119.9 | C15—C16—C11 | 119.44 (13) |
C1—C6—H6 | 119.9 | C15—C16—H16 | 120.3 |
C1—O1—C7 | 118.67 (14) | C11—C16—H16 | 120.3 |
O1—C7—H7A | 109.5 | C13—O2—C17 | 116.73 (15) |
O1—C7—H7B | 109.5 | O2—C17—H17A | 109.5 |
H7A—C7—H7B | 109.5 | O2—C17—H17B | 109.5 |
O1—C7—H7C | 109.5 | H17A—C17—H17B | 109.5 |
H7A—C7—H7C | 109.5 | O2—C17—H17C | 109.5 |
H7B—C7—H7C | 109.5 | H17A—C17—H17C | 109.5 |
N2—C8—C2 | 118.77 (12) | H17B—C17—H17C | 109.5 |
N2—C8—C9 | 113.69 (12) | C15—O3—C18 | 117.33 (13) |
C2—C8—C9 | 127.53 (12) | O3—C18—H18A | 109.5 |
C8—C9—C10 | 102.65 (11) | O3—C18—H18B | 109.5 |
C8—C9—H9A | 111.2 | H18A—C18—H18B | 109.5 |
C10—C9—H9A | 111.2 | O3—C18—H18C | 109.5 |
C8—C9—H9B | 111.2 | H18A—C18—H18C | 109.5 |
C10—C9—H9B | 111.2 | H18B—C18—H18C | 109.5 |
H9A—C9—H9B | 109.2 | O4—C19—N1 | 119.79 (14) |
N1—C10—C11 | 111.67 (12) | O4—C19—C20 | 122.44 (14) |
N1—C10—C9 | 101.24 (10) | N1—C19—C20 | 117.77 (13) |
C11—C10—C9 | 112.00 (11) | C19—C20—H20A | 109.5 |
N1—C10—H10 | 110.5 | C19—C20—H20B | 109.5 |
C11—C10—H10 | 110.5 | H20A—C20—H20B | 109.5 |
C9—C10—H10 | 110.5 | C19—C20—H20C | 109.5 |
C19—N1—N2 | 122.73 (12) | H20A—C20—H20C | 109.5 |
C19—N1—C10 | 124.12 (11) | H20B—C20—H20C | 109.5 |
N2—N1—C10 | 113.02 (11) | ||
O1—C1—C2—C3 | 179.43 (13) | C19—N1—N2—C8 | −177.84 (13) |
C6—C1—C2—C3 | −0.7 (2) | C10—N1—N2—C8 | 6.23 (16) |
O1—C1—C2—C8 | 0.8 (2) | N1—C10—C11—C12 | 145.36 (13) |
C6—C1—C2—C8 | −179.33 (14) | C9—C10—C11—C12 | −101.88 (15) |
C1—C2—C3—C4 | 0.2 (2) | N1—C10—C11—C16 | −38.83 (17) |
C8—C2—C3—C4 | 178.85 (14) | C9—C10—C11—C16 | 73.92 (16) |
C2—C3—C4—C5 | 0.6 (2) | C16—C11—C12—C13 | −0.2 (2) |
C3—C4—C5—C6 | −0.8 (3) | C10—C11—C12—C13 | 175.58 (13) |
C4—C5—C6—C1 | 0.3 (3) | C11—C12—C13—O2 | −179.32 (13) |
O1—C1—C6—C5 | −179.62 (15) | C11—C12—C13—C14 | 0.0 (2) |
C2—C1—C6—C5 | 0.5 (2) | O2—C13—C14—C15 | 179.53 (14) |
C6—C1—O1—C7 | 6.1 (2) | C12—C13—C14—C15 | 0.2 (2) |
C2—C1—O1—C7 | −174.01 (16) | C13—C14—C15—O3 | 179.30 (13) |
C3—C2—C8—N2 | 4.0 (2) | C13—C14—C15—C16 | −0.3 (2) |
C1—C2—C8—N2 | −177.35 (14) | O3—C15—C16—C11 | −179.44 (13) |
C3—C2—C8—C9 | −176.46 (14) | C14—C15—C16—C11 | 0.1 (2) |
C1—C2—C8—C9 | 2.2 (2) | C12—C11—C16—C15 | 0.1 (2) |
N2—C8—C9—C10 | −7.73 (16) | C10—C11—C16—C15 | −175.64 (13) |
C2—C8—C9—C10 | 172.73 (13) | C14—C13—O2—C17 | −2.7 (3) |
C8—C9—C10—N1 | 10.06 (13) | C12—C13—O2—C17 | 176.6 (2) |
C8—C9—C10—C11 | −109.04 (12) | C16—C15—O3—C18 | 0.5 (2) |
C11—C10—N1—C19 | −67.02 (17) | C14—C15—O3—C18 | −179.07 (14) |
C9—C10—N1—C19 | 173.65 (13) | N2—N1—C19—O4 | −179.14 (14) |
C11—C10—N1—N2 | 108.85 (13) | C10—N1—C19—O4 | −3.7 (2) |
C9—C10—N1—N2 | −10.49 (15) | N2—N1—C19—C20 | 0.9 (2) |
C2—C8—N2—N1 | −179.04 (12) | C10—N1—C19—C20 | 176.37 (15) |
C9—C8—N2—N1 | 1.37 (16) |
D—H···A | D—H | H···A | D···A | D—H···A |
C10—H10···O4i | 0.99 | 2.46 | 3.4340 (18) | 167 |
C5—H5···O4ii | 0.94 | 2.59 | 3.309 (2) | 134 |
Symmetry codes: (i) −x+1, −y+1, −z; (ii) x, y, z+1. |
Funding information
The authors acknowledge financial support from the Basic Science Research Program (award No. NRF-2019R1F1A1058747).
References
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