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Acta Crystallogr Sect E Struct Rep Online. 2010 December 1; 66(Pt 12): o3233–o3234.
Published online 2010 November 20. doi:  10.1107/S1600536810047215
PMCID: PMC3011612

1-{[5-(4-Chloro­phen­yl)-1-(4-fluoro­phen­yl)-1H-pyrazol-3-yl]carbon­yl]}piperidin-4-one

Abstract

In the title compound, C21H17ClFN3O2, the 1H-pyrazole ring makes dihedral angles of 36.73 (7), 18.73 (7) and 60.88 (8)°, respectively, with the mean planes of the chloro­phenyl, 4-oxo­piperidine and fluoro­phenyl rings. The mol­ecular structure is stabilized by an intra­molecular C—H(...)N hydrogen bond, which forms an S(6) ring motif. In the crystal, inter­molecular C—H(...)O hydrogen bonds link mol­ecules into chains along [101]. In addition, inter­molecular C—H(...)F hydrogen bonds with an R 2 1(7) ring motif connect neighbouring chains into layers parallel to the ac plane.

Related literature

For pyrazole derivatives and their microbial activities, see: Ragavan et al. (2009 [triangle], 2010 [triangle]). For a related structure, see: Shahani et al. (2010 [triangle]). For ring conformations, see: Cremer & Pople (1975 [triangle]). For hydrogen-bond motifs, see: Bernstein et al. (1995 [triangle]). For bond-length data, see: Allen et al. (1987 [triangle]). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986 [triangle]).

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Object name is e-66-o3233-scheme1.jpg

Experimental

Crystal data

  • C21H17ClFN3O2
  • M r = 397.83
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o3233-efi1.jpg
  • a = 6.0341 (2) Å
  • b = 8.2500 (3) Å
  • c = 10.2448 (3) Å
  • α = 108.837 (1)°
  • β = 104.782 (1)°
  • γ = 92.792 (1)°
  • V = 461.90 (3) Å3
  • Z = 1
  • Mo Kα radiation
  • μ = 0.24 mm−1
  • T = 100 K
  • 0.77 × 0.21 × 0.11 mm

Data collection

  • Bruker SMART APEXII CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2009 [triangle]) T min = 0.837, T max = 0.974
  • 10178 measured reflections
  • 3646 independent reflections
  • 3596 reflections with I > 2σ(I)
  • R int = 0.020

Refinement

  • R[F 2 > 2σ(F 2)] = 0.024
  • wR(F 2) = 0.062
  • S = 1.05
  • 3646 reflections
  • 253 parameters
  • 3 restraints
  • H-atom parameters constrained
  • Δρmax = 0.17 e Å−3
  • Δρmin = −0.22 e Å−3
  • Absolute structure: Flack (1983 [triangle]), 1556 Friedel pairs
  • Flack parameter: 0.06 (3)

Data collection: APEX2 (Bruker, 2009 [triangle]); cell refinement: SAINT (Bruker, 2009 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810047215/is2632sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810047215/is2632Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

HKF and TSH thank Universiti Sains Malaysia (USM) for the Research University Grant (1001/PFIZIK/811160). TSH also thanks USM for the award of a research fellowship. VV is grateful to the DST–India for funding through the Young Scientist Scheme (Fast Track Proposal).

supplementary crystallographic information

Comment

Antibacterial and antifungal activities of the azoles are most widely studied and some of them are in clinical practice as anti-microbial agents. However, the azole-resistant strain had led to the development of new antimicrobial compounds. In particular, pyrazole derivatives are extensively studied and used as antimicrobial agents. Pyrazole is an important class of heterocyclic compounds and many pyrazole derivatives are reported to have the broad spectrum of biological properties such as anti-inflammatory, antifungal, herbicidal, anti-tumour, cytotoxic, molecular modelling and antiviral activities. Pyrazole derivatives also act as antiangiogenic agents, A3 adenosine receptor antagonists, neuropeptide YY5 receptor antagonists, kinase inhibitor for treatment of type 2 diabetes, hyperlipidemia, obesity and thrombopiotinmimetics. Recently urea derivatives of pyrazoles have been reported as potent inhibitors of p38 kinase. Since the high electronegativity of halogens (particularly chlorine and fluorine) in the aromatic part of the drug molecules play an important role in enhancing their biological activity, we are interested to have 4-fluoro or 4-chloro substitution in the aryls of 1,5-diaryl pyrazoles. As part of our on-going research aiming the synthesis of new antimicrobial compounds, we have reported the synthesis of novel pyrazole derivatives and their microbial activities (Ragavan et al., 2009; 2010). The structure of the title compound is presented here.

The asymmetric unit of the title compound (Fig. 1), consists of four rings, namely chlorophenyl (C7–C12/Cl1), 4-oxopiperidine-1-carbaldehyde (C16–C21/N3/O1/O2), fluorophenyl(C1–C6/F1) and 1H-pyrazole (N1/N2/C13–C15) rings. The 1H-pyrazole ring is essentially planar [maximum deviation of 0.002 (1) Å at atoms C13 and C15] and makes dihedral angles of 36.73 (7), 18.73 (7) and 60.88 (8)°, with the chlorophenyl [maximum deviation of 0.0077 (4) Å at atom Cl1], fluorophenyl [maximum deviation of 0.0084 (14) Å at atom C6] and 4-oxopiperidine-1-carbaldehyde [with the r.m.s. deviation of 0.3007 (15) Å] rings. Bond lengths (Allen et al., 1987) and angles are normal and comparable to the related structure (Shahani et al., 2010). The molecular structure is stabilized by an intramolecular C17—H17B···N2 hydrogen bond which forms an S(6) ring motif.

In the crystal packing (Fig. 2), intermolecular C14—H14A···F1iiand C7—H7A···F1ii hydrogen bonds (Table 1) connect the neighbouring molecules, generating an R21(7) ring motif. Intermolecular C2—H2A···O1i hydrogen bonds (Table 1) further link the molecules into two-dimensional sheets parallel to the ac plane.

Experimental

The compound has been synthesized using the method available in the literature (Ragavan et al., 2009) and recrystallized using the methanol-chloroform (1:1) mixture (yield 76%, m.p. 436.2–437.5 K).

Refinement

H atoms were positioned geometrically (C—H = 0.93 or 0.97 Å) and refined using a riding model, with Uiso(H) = 1.2Ueq(C).

Figures

Fig. 1.
The molecular structure of the title compound showing 50% probability displacement ellipsoids and the atom numbering scheme. Intermolecular hydrogen boding (dashed lines) are omitted for clarity.
Fig. 2.
The crystal packing of the title compound viewed along a axis. Intermolecular hydrogen bonds linked the molecules into two-dimensional sheets parallel to the ac plane.

Crystal data

C21H17ClFN3O2Z = 1
Mr = 397.83F(000) = 206
Triclinic, P1Dx = 1.430 Mg m3
Hall symbol: P 1Mo Kα radiation, λ = 0.71073 Å
a = 6.0341 (2) ÅCell parameters from 9510 reflections
b = 8.2500 (3) Åθ = 2.2–35.0°
c = 10.2448 (3) ŵ = 0.24 mm1
α = 108.837 (1)°T = 100 K
β = 104.782 (1)°Needle, colourless
γ = 92.792 (1)°0.77 × 0.21 × 0.11 mm
V = 461.90 (3) Å3

Data collection

Bruker SMART APEXII CCD area-detector diffractometer3646 independent reflections
Radiation source: fine-focus sealed tube3596 reflections with I > 2σ(I)
graphiteRint = 0.020
[var phi] and ω scansθmax = 27.5°, θmin = 2.2°
Absorption correction: multi-scan (SADABS; Bruker, 2009)h = −7→7
Tmin = 0.837, Tmax = 0.974k = −10→10
10178 measured reflectionsl = −13→13

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.024H-atom parameters constrained
wR(F2) = 0.062w = 1/[σ2(Fo2) + (0.0375P)2 + 0.0616P] where P = (Fo2 + 2Fc2)/3
S = 1.05(Δ/σ)max = 0.001
3646 reflectionsΔρmax = 0.17 e Å3
253 parametersΔρmin = −0.21 e Å3
3 restraintsAbsolute structure: Flack (1983), 1556 Friedel pairs
Primary atom site location: structure-invariant direct methodsFlack parameter: 0.06 (3)

Special details

Experimental. The crystal was placed in the cold stream of an Oxford Cyrosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.
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)

xyzUiso*/Ueq
Cl1−0.18751 (5)−0.56629 (4)−0.09987 (4)0.02699 (9)
F10.47475 (18)−0.01865 (15)−0.50052 (9)0.0397 (3)
O11.11635 (17)0.26727 (13)0.53957 (10)0.0225 (2)
O21.85032 (19)0.66828 (16)0.41014 (12)0.0326 (3)
N10.73866 (19)0.06297 (14)0.07455 (11)0.0160 (2)
N20.92725 (19)0.18040 (14)0.16028 (11)0.0171 (2)
N31.27132 (19)0.41856 (15)0.42751 (11)0.0197 (2)
C10.4556 (2)0.08181 (18)−0.13442 (14)0.0192 (3)
H1A0.35850.1228−0.07740.023*
C20.3886 (3)0.06260 (19)−0.27928 (14)0.0235 (3)
H2A0.24620.0894−0.32150.028*
C30.5399 (3)0.00258 (19)−0.35841 (14)0.0254 (3)
C40.7542 (3)−0.03780 (19)−0.30190 (14)0.0243 (3)
H4A0.8525−0.0754−0.35870.029*
C50.8185 (2)−0.02049 (18)−0.15695 (14)0.0200 (3)
H5A0.9602−0.0487−0.11540.024*
C60.6687 (2)0.03934 (16)−0.07542 (13)0.0161 (2)
C70.2588 (2)−0.14175 (17)0.15655 (13)0.0173 (3)
H7A0.2749−0.05370.24370.021*
C80.0689 (2)−0.27130 (18)0.10073 (14)0.0190 (3)
H8A−0.0413−0.27050.14980.023*
C90.0469 (2)−0.40181 (17)−0.02954 (15)0.0192 (3)
C100.2091 (3)−0.40594 (18)−0.10451 (15)0.0199 (3)
H10A0.1914−0.4943−0.19180.024*
C110.3994 (2)−0.27583 (17)−0.04738 (14)0.0188 (3)
H11A0.5098−0.2778−0.09660.023*
C120.4254 (2)−0.14175 (16)0.08395 (13)0.0160 (3)
C130.6292 (2)−0.00678 (16)0.15007 (13)0.0151 (2)
C140.7564 (2)0.07058 (17)0.29276 (13)0.0172 (3)
H14A0.72840.05100.37190.021*
C150.9368 (2)0.18496 (17)0.29308 (13)0.0164 (3)
C161.1168 (2)0.29506 (17)0.42851 (13)0.0168 (3)
C171.2640 (2)0.49206 (18)0.31390 (14)0.0202 (3)
H17A1.23840.61190.34720.024*
H17B1.13650.42870.22960.024*
C181.4914 (3)0.48167 (19)0.27422 (15)0.0225 (3)
H18A1.50730.36140.22980.027*
H18B1.49010.53910.20510.027*
C191.6952 (3)0.56654 (19)0.40686 (15)0.0240 (3)
C201.6883 (2)0.5158 (2)0.53511 (15)0.0239 (3)
H20A1.80150.59550.62020.029*
H20B1.73200.40100.52000.029*
C211.4500 (2)0.51622 (19)0.56187 (14)0.0203 (3)
H21A1.44760.46420.63410.024*
H21B1.41900.63440.59750.024*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Cl10.02313 (16)0.01987 (16)0.03408 (18)−0.00462 (12)0.00415 (13)0.00849 (13)
F10.0393 (5)0.0625 (7)0.0143 (4)−0.0089 (5)0.0024 (4)0.0159 (4)
O10.0247 (5)0.0267 (5)0.0153 (4)0.0003 (4)0.0023 (4)0.0092 (4)
O20.0231 (5)0.0389 (6)0.0328 (6)−0.0016 (5)0.0122 (4)0.0060 (5)
N10.0171 (5)0.0171 (5)0.0133 (5)−0.0006 (4)0.0035 (4)0.0058 (4)
N20.0162 (5)0.0173 (5)0.0150 (5)−0.0008 (4)0.0013 (4)0.0048 (4)
N30.0203 (6)0.0210 (6)0.0139 (5)−0.0026 (5)−0.0014 (4)0.0065 (4)
C10.0194 (6)0.0214 (7)0.0187 (6)−0.0005 (5)0.0056 (5)0.0097 (5)
C20.0222 (7)0.0291 (8)0.0196 (7)−0.0038 (6)0.0001 (5)0.0145 (6)
C30.0308 (7)0.0295 (8)0.0129 (6)−0.0090 (6)0.0024 (5)0.0085 (5)
C40.0281 (7)0.0243 (7)0.0183 (6)−0.0055 (6)0.0098 (6)0.0033 (5)
C50.0199 (6)0.0182 (6)0.0196 (6)−0.0016 (5)0.0057 (5)0.0041 (5)
C60.0197 (6)0.0160 (6)0.0127 (5)−0.0023 (5)0.0040 (5)0.0062 (4)
C70.0203 (6)0.0173 (6)0.0151 (6)0.0034 (5)0.0039 (5)0.0075 (5)
C80.0187 (6)0.0213 (7)0.0206 (6)0.0038 (5)0.0061 (5)0.0114 (5)
C90.0175 (6)0.0159 (6)0.0244 (7)−0.0009 (5)0.0019 (5)0.0109 (5)
C100.0240 (7)0.0165 (6)0.0182 (6)0.0011 (5)0.0051 (5)0.0055 (5)
C110.0211 (6)0.0174 (6)0.0184 (6)0.0012 (5)0.0062 (5)0.0068 (5)
C120.0179 (6)0.0149 (6)0.0155 (5)0.0021 (5)0.0017 (5)0.0081 (5)
C130.0174 (6)0.0142 (6)0.0154 (5)0.0035 (5)0.0055 (5)0.0065 (5)
C140.0206 (6)0.0178 (6)0.0138 (6)0.0028 (5)0.0045 (5)0.0065 (5)
C150.0182 (6)0.0161 (6)0.0147 (6)0.0035 (5)0.0031 (5)0.0060 (5)
C160.0172 (6)0.0172 (6)0.0151 (6)0.0044 (5)0.0027 (5)0.0055 (5)
C170.0202 (6)0.0202 (6)0.0195 (6)−0.0005 (5)0.0022 (5)0.0090 (5)
C180.0258 (7)0.0229 (7)0.0192 (6)0.0035 (6)0.0074 (5)0.0070 (5)
C190.0196 (7)0.0237 (7)0.0260 (7)0.0062 (6)0.0086 (5)0.0033 (6)
C200.0190 (7)0.0258 (7)0.0218 (7)0.0029 (6)0.0021 (5)0.0047 (5)
C210.0192 (6)0.0224 (7)0.0144 (6)−0.0004 (5)0.0011 (5)0.0032 (5)

Geometric parameters (Å, °)

Cl1—C91.7387 (14)C8—C91.3877 (19)
F1—C31.3570 (14)C8—H8A0.9300
O1—C161.2317 (16)C9—C101.385 (2)
O2—C191.2130 (19)C10—C111.394 (2)
N1—N21.3558 (15)C10—H10A0.9300
N1—C131.3701 (17)C11—C121.4045 (18)
N1—C61.4299 (15)C11—H11A0.9300
N2—C151.3352 (16)C12—C131.4714 (18)
N3—C161.3515 (18)C13—C141.3823 (17)
N3—C211.4657 (15)C14—C151.4039 (19)
N3—C171.4684 (17)C14—H14A0.9300
C1—C61.3875 (19)C15—C161.5004 (17)
C1—C21.3881 (18)C17—C181.526 (2)
C1—H1A0.9300C17—H17A0.9700
C2—C31.378 (2)C17—H17B0.9700
C2—H2A0.9300C18—C191.516 (2)
C3—C41.379 (2)C18—H18A0.9700
C4—C51.3927 (18)C18—H18B0.9700
C4—H4A0.9300C19—C201.511 (2)
C5—C61.3862 (18)C20—C211.531 (2)
C5—H5A0.9300C20—H20A0.9700
C7—C81.3903 (19)C20—H20B0.9700
C7—C121.3951 (19)C21—H21A0.9700
C7—H7A0.9300C21—H21B0.9700
N2—N1—C13112.88 (10)C7—C12—C13119.32 (11)
N2—N1—C6118.05 (11)C11—C12—C13121.72 (12)
C13—N1—C6128.81 (11)N1—C13—C14105.49 (12)
C15—N2—N1104.32 (11)N1—C13—C12124.42 (11)
C16—N3—C21118.56 (11)C14—C13—C12130.04 (12)
C16—N3—C17128.10 (11)C13—C14—C15105.57 (12)
C21—N3—C17112.47 (11)C13—C14—H14A127.2
C6—C1—C2119.43 (13)C15—C14—H14A127.2
C6—C1—H1A120.3N2—C15—C14111.75 (11)
C2—C1—H1A120.3N2—C15—C16125.60 (12)
C3—C2—C1117.83 (13)C14—C15—C16122.64 (11)
C3—C2—H2A121.1O1—C16—N3122.03 (11)
C1—C2—H2A121.1O1—C16—C15116.83 (12)
F1—C3—C2118.27 (13)N3—C16—C15121.13 (11)
F1—C3—C4117.82 (13)N3—C17—C18110.09 (11)
C2—C3—C4123.90 (12)N3—C17—H17A109.6
C3—C4—C5117.84 (13)C18—C17—H17A109.6
C3—C4—H4A121.1N3—C17—H17B109.6
C5—C4—H4A121.1C18—C17—H17B109.6
C6—C5—C4119.19 (12)H17A—C17—H17B108.2
C6—C5—H5A120.4C19—C18—C17110.61 (11)
C4—C5—H5A120.4C19—C18—H18A109.5
C5—C6—C1121.79 (12)C17—C18—H18A109.5
C5—C6—N1119.07 (11)C19—C18—H18B109.5
C1—C6—N1119.11 (12)C17—C18—H18B109.5
C8—C7—C12121.09 (12)H18A—C18—H18B108.1
C8—C7—H7A119.5O2—C19—C20122.68 (13)
C12—C7—H7A119.5O2—C19—C18122.62 (14)
C9—C8—C7118.83 (13)C20—C19—C18114.69 (13)
C9—C8—H8A120.6C19—C20—C21113.13 (11)
C7—C8—H8A120.6C19—C20—H20A109.0
C10—C9—C8121.64 (13)C21—C20—H20A109.0
C10—C9—Cl1118.91 (10)C19—C20—H20B109.0
C8—C9—Cl1119.45 (11)C21—C20—H20B109.0
C9—C10—C11119.11 (12)H20A—C20—H20B107.8
C9—C10—H10A120.4N3—C21—C20109.72 (11)
C11—C10—H10A120.4N3—C21—H21A109.7
C10—C11—C12120.45 (13)C20—C21—H21A109.7
C10—C11—H11A119.8N3—C21—H21B109.7
C12—C11—H11A119.8C20—C21—H21B109.7
C7—C12—C11118.89 (13)H21A—C21—H21B108.2
C13—N1—N2—C15−0.07 (13)C6—N1—C13—C128.4 (2)
C6—N1—N2—C15174.57 (11)C7—C12—C13—N1−146.36 (12)
C6—C1—C2—C3−0.5 (2)C11—C12—C13—N136.75 (19)
C1—C2—C3—F1179.21 (13)C7—C12—C13—C1436.9 (2)
C1—C2—C3—C4−0.6 (2)C11—C12—C13—C14−140.04 (14)
F1—C3—C4—C5−178.30 (12)N1—C13—C14—C150.40 (14)
C2—C3—C4—C51.5 (2)C12—C13—C14—C15177.65 (12)
C3—C4—C5—C6−1.3 (2)N1—N2—C15—C140.34 (14)
C4—C5—C6—C10.3 (2)N1—N2—C15—C16179.57 (11)
C4—C5—C6—N1−177.75 (12)C13—C14—C15—N2−0.47 (15)
C2—C1—C6—C50.6 (2)C13—C14—C15—C16−179.73 (11)
C2—C1—C6—N1178.67 (12)C21—N3—C16—O12.92 (18)
N2—N1—C6—C562.36 (15)C17—N3—C16—O1−165.56 (13)
C13—N1—C6—C5−123.97 (15)C21—N3—C16—C15−177.10 (11)
N2—N1—C6—C1−115.72 (14)C17—N3—C16—C1514.4 (2)
C13—N1—C6—C157.94 (19)N2—C15—C16—O1−171.13 (13)
C12—C7—C8—C9−0.09 (18)C14—C15—C16—O18.02 (18)
C7—C8—C9—C100.12 (19)N2—C15—C16—N38.88 (19)
C7—C8—C9—Cl1179.22 (10)C14—C15—C16—N3−171.97 (12)
C8—C9—C10—C110.13 (19)C16—N3—C17—C18−127.53 (14)
Cl1—C9—C10—C11−178.98 (10)C21—N3—C17—C1863.42 (14)
C9—C10—C11—C12−0.41 (19)N3—C17—C18—C19−54.44 (15)
C8—C7—C12—C11−0.19 (18)C17—C18—C19—O2−132.83 (14)
C8—C7—C12—C13−177.17 (11)C17—C18—C19—C2046.56 (16)
C10—C11—C12—C70.44 (19)O2—C19—C20—C21134.59 (15)
C10—C11—C12—C13177.34 (12)C18—C19—C20—C21−44.80 (16)
N2—N1—C13—C14−0.21 (14)C16—N3—C21—C20129.76 (13)
C6—N1—C13—C14−174.15 (12)C17—N3—C21—C20−60.04 (15)
N2—N1—C13—C12−177.66 (11)C19—C20—C21—N349.66 (16)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C2—H2A···O1i0.932.383.1196 (19)136
C7—H7A···F1ii0.932.503.2099 (15)133
C14—H14A···F1ii0.932.413.2614 (17)153
C17—H17B···N20.972.162.9091 (18)133

Symmetry codes: (i) x−1, y, z−1; (ii) x, y, z+1.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: IS2632).

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