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

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ISSN: 2056-9890

Ethyl 2-{[5-(3-chloro­phen­yl)-1-phenyl-1H-pyrazol-3-yl]­­oxy}acetate

aDepartment of Applied Chemistry, College of Science, Nanjing University of Technology, Nanjing 210009, People's Republic of China
*Correspondence e-mail: yangxl@jit.edu.cn

(Received 13 November 2011; accepted 8 December 2011; online 14 December 2011)

The title compound, C19H17ClN2O3, was synthesized by the reaction of 5-(3-chloro­phen­yl)-1-phenyl-1H-pyrazol-3-ol and ethyl 2-bromo­acetate. In the crystal, the C- and N-linked benzene rings are twisted by 45.15 (3) and 53.55 (3)°, respectively, from the plane of the bridging 1H-pyrazole ring.

Related literature

For 1H-pyrazol-3-oxy derivatives, see: Li et al. (2010[Li, Y., Liu, R., Yan, Z., Zhang, X. & Zhu, H. (2010). Bull. Korean Chem. Soc. 31, 3341-3347.]). For alkyl­oxyacetates as bioactive groups, see: Tohyama & Sanemitsu (2001[Tohyama, Y. & Sanemitsu, Y. (2001). EP Patent No. 1122244.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]). For the synthetic procedure, see: Liu et al. (2011[Liu, Y., He, G., Chen, K., Jin, Y., Li, Y. & Zhu, H. (2011). Eur. J. Org. Chem. pp. 5323-5330.]);

[Scheme 1]

Experimental

Crystal data
  • C19H17ClN2O3

  • Mr = 356.80

  • Orthorhombic, P b c a

  • a = 11.6158 (11) Å

  • b = 15.9119 (16) Å

  • c = 19.302 (2) Å

  • V = 3567.6 (6) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.23 mm−1

  • T = 293 K

  • 0.30 × 0.30 × 0.10 mm

Data collection
  • Enraf–Nonius CAD-4 diffractometer

  • Absorption correction: ψ scan (North et al., 1968[North, A. C. T., Phillips, D. C. & Mathews, F. S. (1968). Acta Cryst. A24, 351-359.]) Tmin = 0.933, Tmax = 0.977

  • 6360 measured reflections

  • 3244 independent reflections

  • 1787 reflections with I > 2σ(I)

  • Rint = 0.092

  • 3 standard reflections every 200 reflections intensity decay: 1%

Refinement
  • R[F2 > 2σ(F2)] = 0.055

  • wR(F2) = 0.093

  • S = 1.01

  • 3244 reflections

  • 226 parameters

  • H-atom parameters constrained

  • Δρmax = 0.17 e Å−3

  • Δρmin = −0.17 e Å−3

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994[Enraf-Nonius (1994). CAD-4 EXPRESS. Enraf-Nonius, Delft, The Netherlands.]); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995[Harms, K. & Wocadlo, S. (1995). XCAD4. University of Marburg, Germany.]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

Since the discovery of the strobilurin fungicide pyraclostrobin by BASF scientists, 1H-pyrazol-3-oxy derivatives have attracted considerable attention in chemical and medicinal research because of their low mammalian toxicity and diverse bioactivities (Li et al., 2010). Furthermore, several biological studies have also pointed out the value of alkyloxyacetates (Tohyama & Sanemitsu, 2001) as bioactive groups. Recently, focusing on incorporating an alkyloxyacetate group into 1H-pyrazol-3-oxy derivatives in the hope of obtaining compounds with potential bioactivities, we report here the crystal structure of the title compound (I).

In the molecule of I (Fig.1) the bond lengths (Allen et al., 1987) and angles are within normal ranges. The C-linked benzene ring A (C1—C6) and N-linked benzene ring B (C10—C15) are twisted 45.15 (3)° and 53.55 (3)° from the plane of the bridge 1H-pyrazol ring (N2/N3/C7—C8), respectively. Rings A and B are, of course, planar and the dihedral angle between them is 61.11 (3)°.

Related literature top

For 1H-pyrazol-3-oxy derivatives, see: Li et al. (2010). For alkyloxyacetates as bioactive groups, see: Tohyama & Sanemitsu (2001). For bond-length data, see: Allen et al. (1987). For the synthetic procedure, see: Liu et al. (2011);

Experimental top

The title compound was prepared by the literature method (Liu et al., 2011). Crystals suitable for X-ray analysis were obtained by dissolving I (0.5 g) in ethyl acetate (25 ml) and evaporating the solvent slowly at room temperature for about 10 d.

Refinement top

H atoms were positioned geometrically, with C—H = 0.93, 0.97 and 0.96 Å for aromatic, methylene and methyl H, respectively, and constrained to ride on their parent atoms, with Uiso(H) = xUeq(C), where x = 1.2 for aromatic H, and x = 1.5 for other H.

Computing details top

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994); cell refinement: CAD-4 EXPRESS (Enraf–Nonius, 1994); data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I), with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.
Ethyl 2-{[5-(3-chlorophenyl)-1-phenyl-1H-pyrazol-3-yl]oxy}acetate top
Crystal data top
C19H17ClN2O3Dx = 1.329 Mg m3
Mr = 356.80Melting point: 369 K
Orthorhombic, PbcaMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2abCell parameters from 25 reflections
a = 11.6158 (11) Åθ = 10–13°
b = 15.9119 (16) ŵ = 0.23 mm1
c = 19.302 (2) ÅT = 293 K
V = 3567.6 (6) Å3Block, colourless
Z = 80.30 × 0.30 × 0.10 mm
F(000) = 1488
Data collection top
Enraf–Nonius CAD-4
diffractometer
1787 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.092
Graphite monochromatorθmax = 25.4°, θmin = 2.1°
ω/2θ scansh = 014
Absorption correction: ψ scan
(North et al., 1968)
k = 019
Tmin = 0.933, Tmax = 0.977l = 023
6360 measured reflections3 standard reflections every 200 reflections
3244 independent reflections intensity decay: 1%
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)] = 0.055Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.093H-atom parameters constrained
S = 1.01 w = 1/[σ2(Fo2) + (0.010P)2]
where P = (Fo2 + 2Fc2)/3
3244 reflections(Δ/σ)max < 0.001
226 parametersΔρmax = 0.17 e Å3
0 restraintsΔρmin = 0.17 e Å3
Crystal data top
C19H17ClN2O3V = 3567.6 (6) Å3
Mr = 356.80Z = 8
Orthorhombic, PbcaMo Kα radiation
a = 11.6158 (11) ŵ = 0.23 mm1
b = 15.9119 (16) ÅT = 293 K
c = 19.302 (2) Å0.30 × 0.30 × 0.10 mm
Data collection top
Enraf–Nonius CAD-4
diffractometer
1787 reflections with I > 2σ(I)
Absorption correction: ψ scan
(North et al., 1968)
Rint = 0.092
Tmin = 0.933, Tmax = 0.9773 standard reflections every 200 reflections
6360 measured reflections intensity decay: 1%
3244 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0550 restraints
wR(F2) = 0.093H-atom parameters constrained
S = 1.01Δρmax = 0.17 e Å3
3244 reflectionsΔρmin = 0.17 e Å3
226 parameters
Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Cl0.35737 (6)0.17569 (5)0.39581 (4)0.0686 (3)
O10.00916 (16)0.53604 (11)0.21036 (10)0.0628 (6)
N10.10819 (17)0.42944 (13)0.25540 (13)0.0491 (6)
C10.0080 (2)0.28411 (17)0.43656 (13)0.0535 (8)
H1B0.06530.30540.44470.064*
N20.08809 (16)0.36663 (13)0.30241 (11)0.0453 (6)
O20.18554 (18)0.49472 (12)0.07176 (11)0.0641 (6)
C20.0559 (2)0.22869 (18)0.48294 (14)0.0575 (8)
H2A0.01480.21260.52210.069*
C30.1657 (2)0.19648 (16)0.47169 (14)0.0516 (8)
H3A0.19890.15990.50350.062*
O30.0121 (2)0.43762 (13)0.09175 (12)0.0896 (8)
C40.2242 (2)0.21959 (16)0.41286 (14)0.0450 (7)
C50.1774 (2)0.27566 (16)0.36660 (13)0.0421 (7)
H5A0.21900.29170.32760.050*
C60.0677 (2)0.30848 (16)0.37803 (13)0.0417 (7)
C70.0204 (2)0.36878 (17)0.32760 (13)0.0423 (6)
C80.0733 (2)0.43603 (16)0.29721 (14)0.0506 (7)
H8A0.14800.45520.30450.061*
C90.0090 (2)0.46931 (16)0.25317 (15)0.0485 (7)
C100.1769 (2)0.30433 (16)0.31081 (14)0.0417 (7)
C110.2865 (2)0.32957 (17)0.32679 (13)0.0478 (7)
H11A0.30190.38600.33510.057*
C120.3740 (2)0.27127 (18)0.33060 (15)0.0530 (8)
H12A0.44890.28830.34000.064*
C130.3490 (2)0.18712 (18)0.32025 (15)0.0571 (8)
H13A0.40740.14730.32350.068*
C140.2385 (2)0.16216 (18)0.30514 (15)0.0590 (8)
H14A0.22230.10550.29870.071*
C150.1520 (2)0.22070 (16)0.29954 (14)0.0492 (7)
H15A0.07750.20410.28830.059*
C160.0794 (2)0.55185 (16)0.16175 (16)0.0583 (8)
H16A0.06670.60650.14080.070*
H16B0.15260.55380.18590.070*
C170.0859 (3)0.48651 (18)0.10533 (17)0.0572 (8)
C180.2018 (3)0.4426 (2)0.01132 (19)0.0866 (11)
H18A0.20280.38370.02430.104*
H18B0.13960.45140.02150.104*
C190.3146 (4)0.4671 (3)0.0204 (2)0.1339 (17)
H19A0.32830.43370.06090.201*
H19B0.31240.52550.03300.201*
H19C0.37530.45800.01250.201*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl0.0436 (4)0.0759 (5)0.0863 (6)0.0071 (4)0.0079 (4)0.0128 (5)
O10.0566 (12)0.0455 (11)0.0863 (15)0.0094 (10)0.0137 (12)0.0259 (12)
N10.0422 (13)0.0448 (13)0.0601 (15)0.0010 (11)0.0036 (11)0.0165 (14)
C10.0543 (18)0.0535 (18)0.0527 (17)0.0112 (15)0.0052 (16)0.0014 (17)
N20.0385 (12)0.0426 (13)0.0549 (15)0.0003 (11)0.0041 (11)0.0109 (13)
O20.0703 (14)0.0519 (12)0.0701 (14)0.0005 (11)0.0086 (13)0.0037 (12)
C20.071 (2)0.0544 (19)0.0469 (17)0.0013 (17)0.0090 (16)0.0051 (17)
C30.065 (2)0.0460 (18)0.0441 (18)0.0032 (15)0.0114 (16)0.0000 (15)
O30.0931 (17)0.0774 (16)0.0982 (18)0.0382 (14)0.0138 (16)0.0003 (16)
C40.0440 (16)0.0420 (16)0.0491 (17)0.0059 (13)0.0125 (14)0.0014 (15)
C50.0380 (15)0.0440 (16)0.0442 (15)0.0095 (12)0.0039 (13)0.0002 (15)
C60.0453 (16)0.0393 (16)0.0404 (16)0.0041 (13)0.0033 (13)0.0008 (13)
C70.0386 (14)0.0437 (15)0.0446 (16)0.0019 (14)0.0038 (13)0.0015 (15)
C80.0428 (16)0.0414 (16)0.0676 (19)0.0053 (14)0.0091 (15)0.0080 (16)
C90.0451 (16)0.0377 (15)0.0628 (19)0.0017 (13)0.0007 (16)0.0104 (16)
C100.0382 (15)0.0425 (16)0.0444 (16)0.0019 (13)0.0037 (13)0.0046 (14)
C110.0470 (16)0.0405 (15)0.0560 (17)0.0049 (14)0.0008 (15)0.0019 (16)
C120.0389 (16)0.063 (2)0.0577 (19)0.0015 (15)0.0088 (15)0.0056 (18)
C130.0544 (18)0.0512 (19)0.066 (2)0.0127 (16)0.0039 (18)0.0034 (17)
C140.0554 (18)0.0421 (16)0.079 (2)0.0018 (15)0.0007 (18)0.0016 (19)
C150.0417 (15)0.0468 (17)0.0591 (18)0.0063 (14)0.0032 (15)0.0018 (16)
C160.0614 (19)0.0359 (16)0.078 (2)0.0010 (15)0.0115 (18)0.0153 (18)
C170.068 (2)0.0416 (18)0.062 (2)0.0019 (17)0.0100 (19)0.0162 (19)
C180.111 (3)0.067 (2)0.082 (3)0.014 (2)0.002 (2)0.013 (2)
C190.161 (4)0.118 (4)0.122 (4)0.023 (3)0.041 (4)0.019 (3)
Geometric parameters (Å, º) top
Cl—C41.729 (3)C8—C91.385 (3)
O1—C91.362 (3)C8—H8A0.9300
O1—C161.415 (3)C10—C111.370 (3)
N1—C91.316 (3)C10—C151.379 (3)
N1—N21.370 (3)C11—C121.378 (3)
C1—C21.374 (3)C11—H11A0.9300
C1—C61.381 (3)C12—C131.384 (4)
C1—H1B0.9300C12—H12A0.9300
N2—C71.351 (3)C13—C141.375 (3)
N2—C101.440 (3)C13—H13A0.9300
O2—C171.333 (3)C14—C151.375 (3)
O2—C181.444 (3)C14—H14A0.9300
C2—C31.391 (4)C15—H15A0.9300
C2—H2A0.9300C16—C171.508 (4)
C3—C41.373 (3)C16—H16A0.9700
C3—H3A0.9300C16—H16B0.9700
O3—C171.188 (3)C18—C191.498 (4)
C4—C51.374 (3)C18—H18A0.9700
C5—C61.394 (3)C18—H18B0.9700
C5—H5A0.9300C19—H19A0.9600
C6—C71.473 (3)C19—H19B0.9600
C7—C81.367 (3)C19—H19C0.9600
C9—O1—C16115.3 (2)C10—C11—C12120.0 (3)
C9—N1—N2103.0 (2)C10—C11—H11A120.0
C2—C1—C6120.6 (3)C12—C11—H11A120.0
C2—C1—H1B119.7C11—C12—C13119.3 (3)
C6—C1—H1B119.7C11—C12—H12A120.3
C7—N2—N1112.3 (2)C13—C12—H12A120.3
C7—N2—C10130.2 (2)C14—C13—C12120.3 (3)
N1—N2—C10117.04 (19)C14—C13—H13A119.8
C17—O2—C18116.7 (3)C12—C13—H13A119.8
C1—C2—C3120.4 (3)C15—C14—C13120.2 (3)
C1—C2—H2A119.8C15—C14—H14A119.9
C3—C2—H2A119.8C13—C14—H14A119.9
C4—C3—C2118.9 (3)C14—C15—C10119.2 (2)
C4—C3—H3A120.5C14—C15—H15A120.4
C2—C3—H3A120.5C10—C15—H15A120.4
C3—C4—C5121.0 (2)O1—C16—C17113.1 (2)
C3—C4—Cl119.5 (2)O1—C16—H16A109.0
C5—C4—Cl119.5 (2)C17—C16—H16A109.0
C4—C5—C6120.1 (2)O1—C16—H16B109.0
C4—C5—H5A119.9C17—C16—H16B109.0
C6—C5—H5A119.9H16A—C16—H16B107.8
C1—C6—C5118.9 (2)O3—C17—O2125.8 (3)
C1—C6—C7122.4 (2)O3—C17—C16125.1 (3)
C5—C6—C7118.7 (2)O2—C17—C16109.1 (3)
N2—C7—C8106.6 (2)O2—C18—C19107.1 (3)
N2—C7—C6124.7 (2)O2—C18—H18A110.3
C8—C7—C6128.7 (2)C19—C18—H18A110.3
C7—C8—C9104.6 (2)O2—C18—H18B110.3
C7—C8—H8A127.7C19—C18—H18B110.3
C9—C8—H8A127.7H18A—C18—H18B108.5
N1—C9—O1122.1 (2)C18—C19—H19A109.5
N1—C9—C8113.6 (2)C18—C19—H19B109.5
O1—C9—C8124.3 (2)H19A—C19—H19B109.5
C11—C10—C15120.9 (2)C18—C19—H19C109.5
C11—C10—N2119.3 (2)H19A—C19—H19C109.5
C15—C10—N2119.7 (2)H19B—C19—H19C109.5
C9—N1—N2—C70.1 (3)N2—N1—C9—C80.9 (3)
C9—N1—N2—C10172.7 (2)C16—O1—C9—N18.7 (4)
C6—C1—C2—C30.2 (4)C16—O1—C9—C8170.3 (3)
C1—C2—C3—C41.3 (4)C7—C8—C9—N11.6 (3)
C2—C3—C4—C52.0 (4)C7—C8—C9—O1177.5 (2)
C2—C3—C4—Cl176.5 (2)C7—N2—C10—C11134.0 (3)
C3—C4—C5—C61.6 (4)N1—N2—C10—C1155.0 (3)
Cl—C4—C5—C6176.93 (19)C7—N2—C10—C1549.0 (4)
C2—C1—C6—C50.2 (4)N1—N2—C10—C15122.0 (3)
C2—C1—C6—C7179.0 (2)C15—C10—C11—C121.1 (4)
C4—C5—C6—C10.4 (4)N2—C10—C11—C12175.8 (2)
C4—C5—C6—C7179.7 (2)C10—C11—C12—C132.0 (4)
N1—N2—C7—C81.0 (3)C11—C12—C13—C141.1 (5)
C10—N2—C7—C8172.4 (2)C12—C13—C14—C150.6 (5)
N1—N2—C7—C6178.9 (2)C13—C14—C15—C101.4 (4)
C10—N2—C7—C67.6 (4)C11—C10—C15—C140.6 (5)
C1—C6—C7—N245.5 (4)N2—C10—C15—C14177.5 (2)
C5—C6—C7—N2135.3 (3)C9—O1—C16—C1770.7 (3)
C1—C6—C7—C8134.5 (3)C18—O2—C17—O33.6 (4)
C5—C6—C7—C844.7 (4)C18—O2—C17—C16174.0 (2)
N2—C7—C8—C91.5 (3)O1—C16—C17—O316.5 (4)
C6—C7—C8—C9178.5 (2)O1—C16—C17—O2165.9 (2)
N2—N1—C9—O1178.1 (2)C17—O2—C18—C19175.9 (3)

Experimental details

Crystal data
Chemical formulaC19H17ClN2O3
Mr356.80
Crystal system, space groupOrthorhombic, Pbca
Temperature (K)293
a, b, c (Å)11.6158 (11), 15.9119 (16), 19.302 (2)
V3)3567.6 (6)
Z8
Radiation typeMo Kα
µ (mm1)0.23
Crystal size (mm)0.30 × 0.30 × 0.10
Data collection
DiffractometerEnraf–Nonius CAD-4
diffractometer
Absorption correctionψ scan
(North et al., 1968)
Tmin, Tmax0.933, 0.977
No. of measured, independent and
observed [I > 2σ(I)] reflections
6360, 3244, 1787
Rint0.092
(sin θ/λ)max1)0.604
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.055, 0.093, 1.01
No. of reflections3244
No. of parameters226
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.17, 0.17

Computer programs: CAD-4 EXPRESS (Enraf–Nonius, 1994), XCAD4 (Harms & Wocadlo, 1995), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

 

Acknowledgements

This work was supported by the Industrialization of Scientific Research Promotion Projects of Colleges and Universities in Jiangsu Province. The author also thanks the Center of Testing and Analysis, Nanjing University, for the data collection.

References

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First citationEnraf–Nonius (1994). CAD-4 EXPRESS. Enraf–Nonius, Delft, The Netherlands.
First citationHarms, K. & Wocadlo, S. (1995). XCAD4. University of Marburg, Germany.
First citationLi, Y., Liu, R., Yan, Z., Zhang, X. & Zhu, H. (2010). Bull. Korean Chem. Soc. 31, 3341–3347.  CrossRef CAS
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