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The title compound, C19H18ClFN4O3, was prepared by the reaction of (Z)-ethyl 3-amino-2-cyano-3-(4-fluoro­phen­yl)­acrylate and 4-chloro-3-ethyl-1-methyl-1H-pyrazole-5-carbonyl chloride. The planar pyrazole ring is perpendicular to the benzene ring [dihedral angle 89.70 (10)°]. The mol­ecular conformation is stabilized by intra­molecular C—H...O, N—H...O and N—H...Cl hydrogen bonds.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807042699/rz2156sup1.cif
Contains datablocks I, global

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S1600536807042699/rz2156Isup2.hkl
Contains datablock I

CCDC reference: 663762

Key indicators

  • Single-crystal X-ray study
  • T = 294 K
  • Mean [sigma](C-C) = 0.005 Å
  • R factor = 0.061
  • wR factor = 0.145
  • Data-to-parameter ratio = 15.0

checkCIF/PLATON results

No syntax errors found



Alert level C RINTA01_ALERT_3_C The value of Rint is greater than 0.10 Rint given 0.123 PLAT020_ALERT_3_C The value of Rint is greater than 0.10 ......... 0.12 PLAT026_ALERT_3_C Ratio Observed / Unique Reflections too Low .... 48 Perc. PLAT220_ALERT_2_C Large Non-Solvent C Ueq(max)/Ueq(min) ... 3.24 Ratio PLAT222_ALERT_3_C Large Non-Solvent H Ueq(max)/Ueq(min) ... 3.33 Ratio PLAT340_ALERT_3_C Low Bond Precision on C-C Bonds (x 1000) Ang ... 5 PLAT371_ALERT_2_C Long C(sp2)-C(sp1) Bond C8 - C9 ... 1.43 Ang.
0 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 7 ALERT level C = Check and explain 0 ALERT level G = General alerts; check 0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 2 ALERT type 2 Indicator that the structure model may be wrong or deficient 5 ALERT type 3 Indicator that the structure quality may be low 0 ALERT type 4 Improvement, methodology, query or suggestion 0 ALERT type 5 Informative message, check

Comment top

The title compound is useful as an inhibitor of Pyricularia oryzae, Rhizoctonia solani, Botrytis cinerea and Gibberella zeae. Recently we obtained single crystals of this compound (Heller et al., 2004), and its crystal structure is reported here.

In the molecule of the title compound (Fig. 1), all bond lengths and angles are unexceptional. The pyrazole ring is planar (maximum deviation 0.007 (3) Å for atoms C14 and C15) and oriented perpendicular to the benzene ring, the dihedral angle they form being 89.70 (10)°. The molecular conformation is stabilized by intramolecular C—H···O, N—H···O and N—H···Cl hydrogen bonds (Table 1). The crystal packing is governed only by van der Waals interactions.

Related literature top

For related literature, see: Heller et al. (2004).

Experimental top

To a solution of (Z)-ethyl 3-amino-2-cyano-3-(4-fluorophenyl)acrylate (1.17 g, 5 mmol) in CH2Cl2 (18 ml), 4-chloro-3-ethyl-1-methyl-1H-pyrazole-5-carbonyl chloride (3.88 g, 15 mmol) was added. Subsequently, Et3N (1.52 g, 15 mmol) was dropped into the solution under stirring and the reaction mixture was heated to reflux and stirred for 4 h. After cooling to room temperature, the mixture was filtered off and the resulting white solid was separated. The organic phase was washed with water and dried over anhydrous Na2SO4. After removal of the solvent, a brown dope was obtained. Pure E-isomer of the title compound was separated from the mother liquid by column chromatography. Single crystal suitable for X-ray analysis were obtain by slow evaporation of an ethyl acetate/petroleum ether (3:1 v/v) solution at room temperature over a period of 45 days.

Refinement top

The amino H atom was located in a difference Fourier map and refined with a distance restraint [N—H = 0.87 (3) Å]. Methyl H atoms were placed in calculated positions with C—H = 0.96 Å and the torsion angle was refined to fit the electron density, with Uiso(H) = 1.5 Ueq(C). Other H atoms were placed in calculated positions with C—H = 0.93–0.97 Å and refined in the riding mode with Uiso(H) = 1.2Ueq(C). The ration of observed/unique reflections is low (48%), and the value of Rint is 0.12, due to the poor quality of the diffraction.

Structure description top

The title compound is useful as an inhibitor of Pyricularia oryzae, Rhizoctonia solani, Botrytis cinerea and Gibberella zeae. Recently we obtained single crystals of this compound (Heller et al., 2004), and its crystal structure is reported here.

In the molecule of the title compound (Fig. 1), all bond lengths and angles are unexceptional. The pyrazole ring is planar (maximum deviation 0.007 (3) Å for atoms C14 and C15) and oriented perpendicular to the benzene ring, the dihedral angle they form being 89.70 (10)°. The molecular conformation is stabilized by intramolecular C—H···O, N—H···O and N—H···Cl hydrogen bonds (Table 1). The crystal packing is governed only by van der Waals interactions.

For related literature, see: Heller et al. (2004).

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1999); data reduction: SAINT (Bruker, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2001); software used to prepare material for publication: SHELXTL (Bruker, 2001).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing 30% probability displacement ellipsoids and the atom-numbering scheme.
[Figure 2] Fig. 2. Packing diagram of the title compound, viewed down the a axis.
(Z)-Ethyl 3-(4-chloro-3-ethyl-1-methyl-1H-pyrazole-5-carboxamido)- 2-cyano-3-(4-fluorophenyl)acrylate top
Crystal data top
C19H18ClFN4O3F(000) = 840
Mr = 404.82Dx = 1.360 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 1853 reflections
a = 8.7594 (7) Åθ = 2.5–19.4°
b = 28.192 (3) ŵ = 0.23 mm1
c = 8.5160 (8) ÅT = 294 K
β = 109.885 (2)°Plate, colourless
V = 1977.6 (3) Å30.20 × 0.10 × 0.04 mm
Z = 4
Data collection top
Bruker SMART 1000 CCD area-detector
diffractometer
1860 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.123
Graphite monochromatorθmax = 26.0°, θmin = 1.4°
φ and ω scansh = 1010
20334 measured reflectionsk = 3434
3888 independent reflectionsl = 109
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)] = 0.061Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.145H atoms treated by a mixture of independent and constrained refinement
S = 0.91 w = 1/[σ2(Fo2) + (0.058P)2]
where P = (Fo2 + 2Fc2)/3
3888 reflections(Δ/σ)max < 0.001
259 parametersΔρmax = 0.25 e Å3
0 restraintsΔρmin = 0.33 e Å3
Crystal data top
C19H18ClFN4O3V = 1977.6 (3) Å3
Mr = 404.82Z = 4
Monoclinic, P21/cMo Kα radiation
a = 8.7594 (7) ŵ = 0.23 mm1
b = 28.192 (3) ÅT = 294 K
c = 8.5160 (8) Å0.20 × 0.10 × 0.04 mm
β = 109.885 (2)°
Data collection top
Bruker SMART 1000 CCD area-detector
diffractometer
1860 reflections with I > 2σ(I)
20334 measured reflectionsRint = 0.123
3888 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0610 restraints
wR(F2) = 0.145H atoms treated by a mixture of independent and constrained refinement
S = 0.91Δρmax = 0.25 e Å3
3888 reflectionsΔρmin = 0.33 e Å3
259 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
C10.0303 (4)0.12352 (12)0.9437 (5)0.0510 (9)
C20.0405 (4)0.10853 (13)0.7953 (5)0.0628 (11)
H20.04120.09030.72160.075*
C30.1765 (4)0.12135 (11)0.7589 (4)0.0499 (9)
H30.18750.11140.65910.060*
C40.2981 (4)0.14907 (10)0.8698 (4)0.0355 (8)
C50.2811 (4)0.16295 (11)1.0175 (4)0.0435 (8)
H50.36150.18131.09240.052*
C60.1457 (4)0.14992 (11)1.0563 (4)0.0508 (9)
H60.13420.15901.15660.061*
C70.4382 (3)0.16452 (11)0.8228 (4)0.0364 (8)
C80.4831 (4)0.21105 (11)0.8269 (4)0.0393 (8)
C90.3873 (4)0.24705 (13)0.8674 (4)0.0500 (9)
C100.6234 (4)0.22698 (12)0.7842 (4)0.0496 (9)
C110.7833 (5)0.29406 (14)0.7680 (6)0.0852 (14)
H11A0.80900.27540.68450.102*
H11B0.75930.32620.72650.102*
C120.9218 (6)0.29404 (18)0.9250 (7)0.1152 (19)
H12A0.89340.31111.00870.173*
H12B1.01310.30910.90760.173*
H12C0.94950.26200.96120.173*
C130.5356 (4)0.08297 (11)0.7983 (4)0.0419 (8)
C140.6074 (3)0.05767 (10)0.6913 (4)0.0368 (8)
C150.6086 (4)0.06716 (10)0.5305 (4)0.0420 (8)
C160.6972 (4)0.03064 (12)0.4911 (4)0.0474 (9)
C170.7410 (5)0.02500 (13)0.3371 (4)0.0622 (11)
H17A0.64680.03200.23990.075*
H17B0.77200.00770.32850.075*
C180.8792 (5)0.05739 (14)0.3384 (5)0.0823 (13)
H18A0.85010.08970.35000.123*
H18B0.90050.05390.23560.123*
H18C0.97470.04920.43040.123*
C190.7339 (4)0.00981 (12)0.8945 (4)0.0601 (10)
H19A0.73290.04330.87340.090*
H19B0.65620.00260.94800.090*
H19C0.84020.00050.96590.090*
Cl10.51799 (13)0.11280 (3)0.40193 (12)0.0750 (4)
F10.1038 (2)0.11074 (8)0.9808 (3)0.0846 (7)
N10.3149 (4)0.27709 (11)0.8997 (4)0.0712 (10)
N20.5170 (3)0.13141 (9)0.7615 (4)0.0487 (8)
N30.6914 (3)0.01611 (9)0.7359 (3)0.0437 (7)
N40.7463 (3)0.00016 (9)0.6167 (4)0.0500 (7)
O10.7110 (3)0.20129 (8)0.7383 (3)0.0681 (8)
O20.6422 (3)0.27364 (8)0.7995 (3)0.0695 (8)
O30.4979 (3)0.06497 (8)0.9086 (3)0.0570 (7)
H2A0.584 (4)0.1442 (11)0.718 (4)0.068*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.035 (2)0.062 (2)0.060 (3)0.0047 (18)0.021 (2)0.012 (2)
C20.043 (2)0.082 (3)0.056 (3)0.017 (2)0.008 (2)0.006 (2)
C30.044 (2)0.064 (2)0.043 (2)0.0017 (18)0.0162 (18)0.0029 (18)
C40.0298 (18)0.0344 (17)0.044 (2)0.0045 (14)0.0148 (16)0.0057 (15)
C50.044 (2)0.0418 (19)0.048 (2)0.0061 (16)0.0203 (17)0.0018 (16)
C60.048 (2)0.057 (2)0.053 (2)0.0006 (18)0.025 (2)0.0019 (19)
C70.0335 (18)0.0372 (19)0.039 (2)0.0045 (15)0.0138 (16)0.0015 (15)
C80.0377 (19)0.0390 (19)0.044 (2)0.0014 (15)0.0175 (16)0.0023 (15)
C90.052 (2)0.042 (2)0.065 (3)0.0062 (18)0.032 (2)0.0070 (19)
C100.047 (2)0.045 (2)0.061 (3)0.0047 (18)0.024 (2)0.0002 (18)
C110.083 (3)0.071 (3)0.125 (4)0.033 (2)0.066 (3)0.018 (3)
C120.075 (4)0.151 (5)0.134 (5)0.038 (3)0.055 (4)0.020 (4)
C130.0326 (19)0.045 (2)0.050 (2)0.0013 (15)0.0154 (17)0.0003 (18)
C140.0333 (18)0.0344 (18)0.044 (2)0.0032 (15)0.0141 (16)0.0027 (16)
C150.0384 (19)0.0382 (19)0.048 (2)0.0033 (15)0.0123 (17)0.0059 (17)
C160.049 (2)0.045 (2)0.049 (2)0.0045 (17)0.0190 (18)0.0056 (18)
C170.077 (3)0.063 (2)0.057 (3)0.004 (2)0.035 (2)0.011 (2)
C180.093 (3)0.095 (3)0.078 (3)0.007 (3)0.053 (3)0.008 (3)
C190.073 (3)0.053 (2)0.059 (2)0.0189 (19)0.028 (2)0.022 (2)
Cl10.0929 (8)0.0713 (7)0.0610 (7)0.0272 (6)0.0263 (6)0.0243 (5)
F10.0501 (13)0.125 (2)0.0863 (17)0.0232 (13)0.0327 (12)0.0097 (14)
N10.080 (2)0.051 (2)0.101 (3)0.0108 (18)0.054 (2)0.0082 (19)
N20.0528 (19)0.0356 (17)0.072 (2)0.0037 (14)0.0398 (16)0.0049 (15)
N30.0450 (17)0.0389 (16)0.0499 (18)0.0085 (13)0.0195 (14)0.0048 (14)
N40.0513 (18)0.0445 (17)0.0588 (19)0.0021 (14)0.0246 (16)0.0079 (16)
O10.0695 (18)0.0550 (16)0.104 (2)0.0085 (14)0.0615 (17)0.0030 (15)
O20.0747 (18)0.0477 (15)0.107 (2)0.0216 (13)0.0577 (17)0.0145 (14)
O30.0658 (17)0.0533 (15)0.0635 (17)0.0070 (12)0.0370 (15)0.0107 (13)
Geometric parameters (Å, º) top
C1—C61.354 (4)C12—H12B0.9600
C1—C21.364 (5)C12—H12C0.9600
C1—F11.365 (3)C13—O31.208 (4)
C2—C31.377 (4)C13—N21.398 (4)
C2—H20.9300C13—C141.458 (4)
C3—C41.398 (4)C14—N31.367 (4)
C3—H30.9300C14—C151.399 (4)
C4—C51.373 (4)C15—C161.397 (4)
C4—C71.480 (4)C15—Cl11.701 (3)
C5—C61.385 (4)C16—N41.325 (4)
C5—H50.9300C16—C171.495 (5)
C6—H60.9300C17—C181.513 (5)
C7—N21.366 (4)C17—H17A0.9700
C7—C81.366 (4)C17—H17B0.9700
C8—C91.432 (5)C18—H18A0.9600
C8—C101.465 (4)C18—H18B0.9600
C9—N11.146 (4)C18—H18C0.9600
C10—O11.213 (4)C19—N31.468 (4)
C10—O21.326 (4)C19—H19A0.9600
C11—C121.468 (6)C19—H19B0.9600
C11—O21.469 (4)C19—H19C0.9600
C11—H11A0.9700N2—H2A0.87 (3)
C11—H11B0.9700N3—N41.340 (3)
C12—H12A0.9600
C6—C1—C2123.9 (3)H12B—C12—H12C109.5
C6—C1—F1118.4 (3)O3—C13—N2122.9 (3)
C2—C1—F1117.7 (3)O3—C13—C14124.8 (3)
C1—C2—C3117.5 (3)N2—C13—C14112.3 (3)
C1—C2—H2121.2N3—C14—C15104.7 (3)
C3—C2—H2121.2N3—C14—C13123.4 (3)
C2—C3—C4120.9 (3)C15—C14—C13131.8 (3)
C2—C3—H3119.6C16—C15—C14106.5 (3)
C4—C3—H3119.6C16—C15—Cl1125.3 (3)
C5—C4—C3118.9 (3)C14—C15—Cl1128.1 (3)
C5—C4—C7121.5 (3)N4—C16—C15109.8 (3)
C3—C4—C7119.6 (3)N4—C16—C17122.0 (3)
C4—C5—C6120.8 (3)C15—C16—C17128.2 (3)
C4—C5—H5119.6C16—C17—C18111.9 (3)
C6—C5—H5119.6C16—C17—H17A109.2
C1—C6—C5118.1 (3)C18—C17—H17A109.2
C1—C6—H6121.0C16—C17—H17B109.2
C5—C6—H6121.0C18—C17—H17B109.2
N2—C7—C8119.2 (3)H17A—C17—H17B107.9
N2—C7—C4118.4 (3)C17—C18—H18A109.5
C8—C7—C4122.2 (3)C17—C18—H18B109.5
C7—C8—C9120.0 (3)H18A—C18—H18B109.5
C7—C8—C10123.1 (3)C17—C18—H18C109.5
C9—C8—C10116.9 (3)H18A—C18—H18C109.5
N1—C9—C8177.4 (4)H18B—C18—H18C109.5
O1—C10—O2123.5 (3)N3—C19—H19A109.5
O1—C10—C8125.0 (3)N3—C19—H19B109.5
O2—C10—C8111.5 (3)H19A—C19—H19B109.5
C12—C11—O2108.7 (4)N3—C19—H19C109.5
C12—C11—H11A110.0H19A—C19—H19C109.5
O2—C11—H11A110.0H19B—C19—H19C109.5
C12—C11—H11B110.0C7—N2—C13128.1 (3)
O2—C11—H11B110.0C7—N2—H2A112 (2)
H11A—C11—H11B108.3C13—N2—H2A117 (2)
C11—C12—H12A109.5N4—N3—C14112.0 (3)
C11—C12—H12B109.5N4—N3—C19119.1 (3)
H12A—C12—H12B109.5C14—N3—C19128.8 (3)
C11—C12—H12C109.5C16—N4—N3107.0 (3)
H12A—C12—H12C109.5C10—O2—C11117.1 (3)
C6—C1—C2—C30.2 (6)N3—C14—C15—C161.2 (3)
F1—C1—C2—C3179.7 (3)C13—C14—C15—C16179.7 (3)
C1—C2—C3—C40.6 (5)N3—C14—C15—Cl1177.4 (2)
C2—C3—C4—C50.8 (5)C13—C14—C15—Cl11.7 (5)
C2—C3—C4—C7176.6 (3)C14—C15—C16—N40.7 (4)
C3—C4—C5—C60.2 (5)Cl1—C15—C16—N4177.9 (2)
C7—C4—C5—C6177.1 (3)C14—C15—C16—C17177.0 (3)
C2—C1—C6—C50.8 (5)Cl1—C15—C16—C174.3 (5)
F1—C1—C6—C5179.7 (3)N4—C16—C17—C18100.9 (4)
C4—C5—C6—C10.6 (5)C15—C16—C17—C1876.6 (5)
C5—C4—C7—N2134.2 (3)C8—C7—N2—C13154.6 (3)
C3—C4—C7—N248.5 (4)C4—C7—N2—C1330.3 (5)
C5—C4—C7—C850.8 (4)O3—C13—N2—C79.2 (5)
C3—C4—C7—C8126.5 (3)C14—C13—N2—C7171.9 (3)
N2—C7—C8—C9170.9 (3)C15—C14—N3—N41.3 (3)
C4—C7—C8—C94.0 (5)C13—C14—N3—N4179.5 (3)
N2—C7—C8—C106.4 (5)C15—C14—N3—C19177.4 (3)
C4—C7—C8—C10178.7 (3)C13—C14—N3—C193.4 (5)
C7—C8—C10—O11.6 (6)C15—C16—N4—N30.1 (4)
C9—C8—C10—O1175.8 (3)C17—C16—N4—N3178.0 (3)
C7—C8—C10—O2179.4 (3)C14—N3—N4—C160.9 (3)
C9—C8—C10—O23.3 (4)C19—N3—N4—C16177.4 (3)
O3—C13—C14—N323.6 (5)O1—C10—O2—C113.8 (6)
N2—C13—C14—N3155.2 (3)C8—C10—O2—C11177.2 (3)
O3—C13—C14—C15155.3 (3)C12—C11—O2—C1088.6 (4)
N2—C13—C14—C1525.8 (5)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C19—H19B···O30.962.312.983 (4)126
N2—H2A···O10.87 (3)1.93 (3)2.653 (3)139 (3)
N2—H2A···Cl10.87 (3)2.70 (3)3.110 (3)110 (3)

Experimental details

Crystal data
Chemical formulaC19H18ClFN4O3
Mr404.82
Crystal system, space groupMonoclinic, P21/c
Temperature (K)294
a, b, c (Å)8.7594 (7), 28.192 (3), 8.5160 (8)
β (°) 109.885 (2)
V3)1977.6 (3)
Z4
Radiation typeMo Kα
µ (mm1)0.23
Crystal size (mm)0.20 × 0.10 × 0.04
Data collection
DiffractometerBruker SMART 1000 CCD area-detector
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
20334, 3888, 1860
Rint0.123
(sin θ/λ)max1)0.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.061, 0.145, 0.91
No. of reflections3888
No. of parameters259
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.25, 0.33

Computer programs: SMART (Bruker, 1998), SAINT (Bruker, 1999), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), SHELXTL (Bruker, 2001).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C19—H19B···O30.962.312.983 (4)126.2
N2—H2A···O10.87 (3)1.93 (3)2.653 (3)139 (3)
N2—H2A···Cl10.87 (3)2.70 (3)3.110 (3)110 (3)
 

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