organic compounds
3-(2-Hydroxyphenyl)-5-(2-methoxyphenyl)-1H-pyrazole
aDepartment of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan, and bInstitut für Anorganische Chemie, J. W. Goethe-Universität, Max-von-Laue-Strasse 7, 60438 Frankfurt/Main, Germany
*Correspondence e-mail: flavonoids@hotmail.com
The title compound, C16H14N2O2, was derived from 1-(2-hydroxyphenyl)-3-(2-methoxyphenyl)propane-1,3-dione. The molecule is essentially planar (r.m.s. deviation for all non-H atoms = 0.089 Å). Two intramolecular hydrogen bonds stabilize the molecular conformation and one N—H⋯O hydrogen bond stabilizes the crystal structure.
Related literature
For related literature, see: Ahmad et al. (1990, 1997); Ezava et al. (2005); Feierman & Cederbaum (1986); Sanz et al. (1998); Alcaraz et al. (1993); Hamper et al. (1997); Fujio (1999).
Experimental
Crystal data
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Data collection
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Refinement
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Data collection: X-AREA (Stoe & Cie, 2001); cell X-AREA; data reduction: X-AREA; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL-Plus (Sheldrick, 2008); software used to prepare material for publication: SHELXL97.
Supporting information
10.1107/S1600536808025725/bx2163sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536808025725/bx2163Isup2.hkl
1-(2'-hydroxyphenyl)-3-(2''-methoxyphenyl) propane-1,3-dione was prepared by a modified Baker Venkataram rearrangement as reported earlier (Ahmad et al., 1997). Purification was carried out by recrystallization using absolute ethanol. 1-H-3(2-hydroxyphenyl)-5-(2-methoxyphenyl) pyrazole was synthesized by reacting hydrazine hydrate (0.5 g, 10 mmol) with 1-(2-hydroxyphenyl)-3-(2-methoxyphenyl) propane-1,3-dione (2.7 g, 10 mmol) in 100 ml of absolute ethanol. The mixture was refluxed for seven hours. Solvent was removed under reduced pressure. Compound (II) was synthesized by adding 0.1 mole of phenyl hydrazine in 0.1 mole of compound (II) dissolved in 200 ml of absolute ethanol. The mixture was refluxed for 7 h. Solvent was removed under reduced pressure. Highly viscous residue was recrystallized using absolute ethanol. (Yield: 96%, m.p: 456k)
In the absence of anomalous scatterers 1544 Friedel pairs were merged. H atoms were located in a difference map, but those bonded to C were geometrically positioned and refined using a riding model with fixed individual displacement parameters [U(H) = 1.2 Ueq(C) or U(H) = 1.5 Ueq(Cmethyl)] and with C—H = 0.95 Å or Cmethyl—H = 0.98 Å. The methyl group was allowed to rotate but not to tip. The H atoms bonded to N and O were freely refined.
Data collection: X-AREA (Stoe & Cie, 2001); cell
X-AREA (Stoe & Cie, 2001); data reduction: X-AREA (Stoe & Cie, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL-Plus (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).Fig. 1. Perspective view of the title compound with the atom numbering scheme; displacement ellipsoids are at the 50% probability level; H atoms are drawn as small spheres of arbitrary radii. |
C16H14N2O2 | Dx = 1.322 Mg m−3 |
Mr = 266.29 | Melting point: 456 K |
Orthorhombic, Pna21 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P 2c -2n | Cell parameters from 11915 reflections |
a = 17.5626 (15) Å | θ = 3.4–29.6° |
b = 10.2239 (7) Å | µ = 0.09 mm−1 |
c = 7.4513 (7) Å | T = 173 K |
V = 1337.94 (19) Å3 | Block, light yellow |
Z = 4 | 0.27 × 0.25 × 0.24 mm |
F(000) = 560 |
Stoe IPDSII two-circle diffractometer | 1620 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.057 |
Graphite monochromator | θmax = 28.3°, θmin = 3.6° |
ω scans | h = −20→23 |
10969 measured reflections | k = −11→13 |
1777 independent reflections | l = −8→9 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.034 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.091 | w = 1/[σ2(Fo2) + (0.0644P)2 + 0.0395P] where P = (Fo2 + 2Fc2)/3 |
S = 1.03 | (Δ/σ)max < 0.001 |
1777 reflections | Δρmax = 0.18 e Å−3 |
191 parameters | Δρmin = −0.16 e Å−3 |
1 restraint | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.049 (6) |
C16H14N2O2 | V = 1337.94 (19) Å3 |
Mr = 266.29 | Z = 4 |
Orthorhombic, Pna21 | Mo Kα radiation |
a = 17.5626 (15) Å | µ = 0.09 mm−1 |
b = 10.2239 (7) Å | T = 173 K |
c = 7.4513 (7) Å | 0.27 × 0.25 × 0.24 mm |
Stoe IPDSII two-circle diffractometer | 1620 reflections with I > 2σ(I) |
10969 measured reflections | Rint = 0.057 |
1777 independent reflections |
R[F2 > 2σ(F2)] = 0.034 | 1 restraint |
wR(F2) = 0.091 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | Δρmax = 0.18 e Å−3 |
1777 reflections | Δρmin = −0.16 e Å−3 |
191 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.49830 (7) | 0.72482 (13) | 0.76358 (19) | 0.0401 (3) | |
O2 | 0.42612 (9) | 1.04511 (15) | 0.0584 (2) | 0.0507 (4) | |
H2 | 0.441 (2) | 0.992 (4) | 0.165 (6) | 0.093 (11)* | |
N1 | 0.44362 (8) | 0.80017 (15) | 0.4520 (2) | 0.0340 (3) | |
H1 | 0.4833 (15) | 0.825 (3) | 0.525 (4) | 0.058 (7)* | |
N2 | 0.43083 (8) | 0.86611 (15) | 0.2984 (2) | 0.0369 (3) | |
C1 | 0.39489 (9) | 0.69783 (15) | 0.4736 (2) | 0.0289 (3) | |
C2 | 0.34823 (9) | 0.69776 (15) | 0.3232 (2) | 0.0306 (3) | |
H2A | 0.3083 | 0.6381 | 0.2968 | 0.037* | |
C3 | 0.37225 (9) | 0.80434 (16) | 0.2179 (2) | 0.0304 (3) | |
C11 | 0.39509 (9) | 0.61110 (16) | 0.6314 (2) | 0.0306 (3) | |
C12 | 0.44651 (9) | 0.62379 (17) | 0.7757 (2) | 0.0339 (3) | |
C13 | 0.44373 (11) | 0.5373 (2) | 0.9203 (3) | 0.0425 (4) | |
H13 | 0.4788 | 0.5461 | 1.0165 | 0.051* | |
C14 | 0.38945 (12) | 0.4381 (2) | 0.9235 (3) | 0.0461 (5) | |
H14 | 0.3882 | 0.3786 | 1.0214 | 0.055* | |
C15 | 0.33733 (11) | 0.42539 (19) | 0.7852 (3) | 0.0437 (4) | |
H15 | 0.2998 | 0.3585 | 0.7891 | 0.052* | |
C16 | 0.34031 (10) | 0.51098 (17) | 0.6410 (3) | 0.0353 (4) | |
H16 | 0.3045 | 0.5018 | 0.5463 | 0.042* | |
C17 | 0.55036 (12) | 0.7438 (3) | 0.9090 (3) | 0.0520 (5) | |
H17A | 0.5825 | 0.6660 | 0.9222 | 0.078* | |
H17B | 0.5218 | 0.7583 | 1.0202 | 0.078* | |
H17C | 0.5825 | 0.8201 | 0.8843 | 0.078* | |
C31 | 0.34524 (9) | 0.85273 (17) | 0.0429 (2) | 0.0314 (3) | |
C32 | 0.37398 (10) | 0.96997 (18) | −0.0313 (3) | 0.0367 (4) | |
C33 | 0.34958 (11) | 1.0130 (2) | −0.1993 (3) | 0.0438 (4) | |
H33 | 0.3693 | 1.0919 | −0.2482 | 0.053* | |
C34 | 0.29652 (12) | 0.9407 (2) | −0.2952 (3) | 0.0437 (4) | |
H34 | 0.2805 | 0.9700 | −0.4102 | 0.052* | |
C35 | 0.26648 (11) | 0.82574 (19) | −0.2245 (3) | 0.0417 (4) | |
H35 | 0.2297 | 0.7772 | −0.2900 | 0.050* | |
C36 | 0.29090 (10) | 0.78266 (17) | −0.0569 (2) | 0.0354 (4) | |
H36 | 0.2704 | 0.7041 | −0.0089 | 0.042* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0371 (6) | 0.0507 (8) | 0.0327 (6) | −0.0037 (5) | −0.0084 (5) | 0.0025 (6) |
O2 | 0.0531 (8) | 0.0541 (8) | 0.0448 (8) | −0.0219 (7) | −0.0050 (7) | 0.0142 (7) |
N1 | 0.0363 (7) | 0.0385 (7) | 0.0273 (7) | −0.0070 (6) | −0.0052 (6) | 0.0026 (6) |
N2 | 0.0390 (7) | 0.0402 (7) | 0.0314 (8) | −0.0087 (6) | −0.0060 (6) | 0.0038 (6) |
C1 | 0.0298 (7) | 0.0302 (7) | 0.0268 (8) | 0.0005 (6) | −0.0005 (6) | −0.0037 (6) |
C2 | 0.0306 (7) | 0.0329 (7) | 0.0283 (8) | −0.0029 (6) | −0.0024 (6) | −0.0014 (6) |
C3 | 0.0304 (7) | 0.0336 (8) | 0.0271 (8) | −0.0008 (6) | −0.0013 (6) | −0.0018 (6) |
C11 | 0.0325 (7) | 0.0330 (7) | 0.0263 (7) | 0.0057 (6) | 0.0020 (6) | −0.0017 (6) |
C12 | 0.0325 (7) | 0.0394 (8) | 0.0299 (8) | 0.0063 (6) | 0.0008 (6) | −0.0018 (7) |
C13 | 0.0413 (9) | 0.0537 (11) | 0.0326 (9) | 0.0113 (8) | −0.0018 (7) | 0.0071 (8) |
C14 | 0.0493 (10) | 0.0513 (11) | 0.0378 (10) | 0.0074 (8) | 0.0033 (8) | 0.0156 (9) |
C15 | 0.0476 (9) | 0.0410 (9) | 0.0426 (11) | −0.0005 (7) | 0.0046 (8) | 0.0065 (8) |
C16 | 0.0389 (8) | 0.0333 (8) | 0.0337 (9) | 0.0004 (7) | 0.0005 (7) | −0.0010 (7) |
C17 | 0.0431 (10) | 0.0746 (14) | 0.0384 (11) | −0.0055 (10) | −0.0137 (8) | 0.0031 (10) |
C31 | 0.0314 (7) | 0.0365 (8) | 0.0263 (8) | 0.0041 (6) | 0.0016 (6) | −0.0006 (6) |
C32 | 0.0357 (8) | 0.0434 (9) | 0.0310 (9) | −0.0011 (7) | 0.0048 (7) | 0.0015 (7) |
C33 | 0.0483 (10) | 0.0488 (10) | 0.0342 (10) | 0.0069 (8) | 0.0084 (8) | 0.0103 (8) |
C34 | 0.0510 (10) | 0.0530 (10) | 0.0271 (8) | 0.0189 (9) | −0.0001 (7) | 0.0001 (8) |
C35 | 0.0464 (9) | 0.0464 (9) | 0.0324 (9) | 0.0122 (7) | −0.0083 (7) | −0.0067 (8) |
C36 | 0.0384 (8) | 0.0370 (8) | 0.0307 (8) | 0.0036 (7) | −0.0040 (7) | −0.0037 (7) |
O1—C12 | 1.379 (2) | C14—C15 | 1.384 (3) |
O1—C17 | 1.431 (2) | C14—H14 | 0.9500 |
O2—C32 | 1.369 (2) | C15—C16 | 1.387 (3) |
O2—H2 | 0.99 (4) | C15—H15 | 0.9500 |
N1—N2 | 1.347 (2) | C16—H16 | 0.9500 |
N1—C1 | 1.361 (2) | C17—H17A | 0.9800 |
N1—H1 | 0.92 (3) | C17—H17B | 0.9800 |
N2—C3 | 1.348 (2) | C17—H17C | 0.9800 |
C1—C2 | 1.388 (2) | C31—C36 | 1.406 (2) |
C1—C11 | 1.473 (2) | C31—C32 | 1.413 (2) |
C2—C3 | 1.408 (2) | C32—C33 | 1.395 (3) |
C2—H2A | 0.9500 | C33—C34 | 1.387 (3) |
C3—C31 | 1.473 (2) | C33—H33 | 0.9500 |
C11—C16 | 1.407 (2) | C34—C35 | 1.392 (3) |
C11—C12 | 1.410 (2) | C34—H34 | 0.9500 |
C12—C13 | 1.394 (3) | C35—C36 | 1.392 (3) |
C13—C14 | 1.392 (3) | C35—H35 | 0.9500 |
C13—H13 | 0.9500 | C36—H36 | 0.9500 |
C12—O1—C17 | 118.24 (16) | C16—C15—H15 | 120.2 |
C32—O2—H2 | 105 (2) | C15—C16—C11 | 121.61 (18) |
N2—N1—C1 | 112.35 (14) | C15—C16—H16 | 119.2 |
N2—N1—H1 | 119.2 (18) | C11—C16—H16 | 119.2 |
C1—N1—H1 | 128.3 (18) | O1—C17—H17A | 109.5 |
N1—N2—C3 | 105.72 (14) | O1—C17—H17B | 109.5 |
N1—C1—C2 | 106.03 (15) | H17A—C17—H17B | 109.5 |
N1—C1—C11 | 123.76 (15) | O1—C17—H17C | 109.5 |
C2—C1—C11 | 130.20 (14) | H17A—C17—H17C | 109.5 |
C1—C2—C3 | 105.82 (14) | H17B—C17—H17C | 109.5 |
C1—C2—H2A | 127.1 | C36—C31—C32 | 117.91 (16) |
C3—C2—H2A | 127.1 | C36—C31—C3 | 121.03 (15) |
N2—C3—C2 | 110.08 (15) | C32—C31—C3 | 121.05 (16) |
N2—C3—C31 | 118.85 (15) | O2—C32—C33 | 117.80 (17) |
C2—C3—C31 | 131.07 (15) | O2—C32—C31 | 121.61 (17) |
C16—C11—C12 | 117.79 (16) | C33—C32—C31 | 120.59 (18) |
C16—C11—C1 | 118.49 (15) | C34—C33—C32 | 120.02 (18) |
C12—C11—C1 | 123.71 (15) | C34—C33—H33 | 120.0 |
O1—C12—C13 | 123.28 (17) | C32—C33—H33 | 120.0 |
O1—C12—C11 | 116.16 (15) | C33—C34—C35 | 120.64 (18) |
C13—C12—C11 | 120.56 (17) | C33—C34—H34 | 119.7 |
C14—C13—C12 | 119.95 (18) | C35—C34—H34 | 119.7 |
C14—C13—H13 | 120.0 | C36—C35—C34 | 119.34 (18) |
C12—C13—H13 | 120.0 | C36—C35—H35 | 120.3 |
C15—C14—C13 | 120.55 (18) | C34—C35—H35 | 120.3 |
C15—C14—H14 | 119.7 | C35—C36—C31 | 121.49 (17) |
C13—C14—H14 | 119.7 | C35—C36—H36 | 119.3 |
C14—C15—C16 | 119.51 (18) | C31—C36—H36 | 119.3 |
C14—C15—H15 | 120.2 | ||
C1—N1—N2—C3 | −0.2 (2) | C12—C13—C14—C15 | −0.9 (3) |
N2—N1—C1—C2 | 0.46 (19) | C13—C14—C15—C16 | 1.2 (3) |
N2—N1—C1—C11 | −178.61 (14) | C14—C15—C16—C11 | −0.1 (3) |
N1—C1—C2—C3 | −0.50 (18) | C12—C11—C16—C15 | −1.2 (3) |
C11—C1—C2—C3 | 178.48 (16) | C1—C11—C16—C15 | 179.75 (16) |
N1—N2—C3—C2 | −0.1 (2) | N2—C3—C31—C36 | 172.07 (16) |
N1—N2—C3—C31 | −179.01 (14) | C2—C3—C31—C36 | −6.5 (3) |
C1—C2—C3—N2 | 0.4 (2) | N2—C3—C31—C32 | −7.0 (2) |
C1—C2—C3—C31 | 179.10 (16) | C2—C3—C31—C32 | 174.43 (18) |
N1—C1—C11—C16 | 178.05 (15) | C36—C31—C32—O2 | 178.95 (17) |
C2—C1—C11—C16 | −0.8 (3) | C3—C31—C32—O2 | −2.0 (3) |
N1—C1—C11—C12 | −0.9 (2) | C36—C31—C32—C33 | −0.8 (2) |
C2—C1—C11—C12 | −179.75 (17) | C3—C31—C32—C33 | 178.21 (15) |
C17—O1—C12—C13 | −1.8 (3) | O2—C32—C33—C34 | −179.68 (18) |
C17—O1—C12—C11 | 178.37 (16) | C31—C32—C33—C34 | 0.1 (3) |
C16—C11—C12—O1 | −178.60 (15) | C32—C33—C34—C35 | 0.7 (3) |
C1—C11—C12—O1 | 0.4 (2) | C33—C34—C35—C36 | −0.8 (3) |
C16—C11—C12—C13 | 1.5 (2) | C34—C35—C36—C31 | 0.1 (3) |
C1—C11—C12—C13 | −179.50 (16) | C32—C31—C36—C35 | 0.8 (2) |
O1—C12—C13—C14 | 179.62 (17) | C3—C31—C36—C35 | −178.30 (16) |
C11—C12—C13—C14 | −0.5 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2···N2 | 0.99 (4) | 1.64 (4) | 2.560 (2) | 152 (3) |
N1—H1···O1 | 0.92 (3) | 2.07 (3) | 2.628 (2) | 118 (2) |
N1—H1···O2i | 0.92 (3) | 2.09 (3) | 2.892 (2) | 146 (3) |
Symmetry code: (i) −x+1, −y+2, z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C16H14N2O2 |
Mr | 266.29 |
Crystal system, space group | Orthorhombic, Pna21 |
Temperature (K) | 173 |
a, b, c (Å) | 17.5626 (15), 10.2239 (7), 7.4513 (7) |
V (Å3) | 1337.94 (19) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.27 × 0.25 × 0.24 |
Data collection | |
Diffractometer | Stoe IPDSII two-circle diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 10969, 1777, 1620 |
Rint | 0.057 |
(sin θ/λ)max (Å−1) | 0.667 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.034, 0.091, 1.03 |
No. of reflections | 1777 |
No. of parameters | 191 |
No. of restraints | 1 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.18, −0.16 |
Computer programs: X-AREA (Stoe & Cie, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XP in SHELXTL-Plus (Sheldrick, 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2···N2 | 0.99 (4) | 1.64 (4) | 2.560 (2) | 152 (3) |
N1—H1···O1 | 0.92 (3) | 2.07 (3) | 2.628 (2) | 118 (2) |
N1—H1···O2i | 0.92 (3) | 2.09 (3) | 2.892 (2) | 146 (3) |
Symmetry code: (i) −x+1, −y+2, z+1/2. |
Acknowledgements
AH is grateful to the Higher Education Commission of Pakistan for a grant.
References
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3,5-substituted Pyrazoles are important class of compounds.These have been proven to be a selective inhibitor of COX in isoenzyme in human blood and are used for the development of anti-inflamatory drugs and analgesic medicines (Ezava et al., 2005). Disubstituted pyrazoles have been reported as an important intermediate in the synthesis of herbicides (US patent 5191087, 1993; US patent 5698708, 1997) and for the treatmet of pain and disorders such as Arthritis (US patent 5908857, 1999).Pyrazoles are inhibitors of alchol dehydrogenase and have been found to be effective inhibitors for the oxidation of ethanol by liver microsomes (Feierman & Cederbaum, 1986). 3,5-disubstituted pyrazoles are also uesd to form solid dinuclear complexes (Sanz et al., 1998). The molecule is essentially planar (r.m.s. deviation for all non-H atoms 0.089 Å). Two intramolecular hydrogen bonds stabilize the molecular conformation and one N—H···O hydrogen bond is stabilizing the crystal structure.