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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 65| Part 8| August 2009| Pages o2040-o2041

2-Phenyl-5-(tri­fluoro­meth­yl)pyrazol-3(2H)-one

aDepto. de Química, Universidade Federal de Santa Catarina, 88040-900 Florianópolis, SC, Brazil
*Correspondence e-mail: hugo@qmc.ufsc.br

(Received 11 July 2009; accepted 23 July 2009; online 29 July 2009)

The title compound, C10H7F3N2O, is an analogue of pyrazolone derivatives with potential analgesic and anti-inflammatory properties. Its mol­ecular structure consists of phenyl and pyrazol-3(2H)-one units with a dihedral angle between the mean planes of the rings of 33.0 (1)°. The crystal structure is stabilized by an inter­molecular hydrogen bond between the N—H group and the carbonyl O atom of the pyrazol-3(2H)-one ring which links the mol­ecules into supra­molecular C(5) chains along [001] and by weak ππ stacking inter­actions between the phenyl rings [centroid-centroid distance = 3.881 (2) Å]. The F atoms are disordered over two positions with refined site occupancies of 0.768(11) and 0.232(11).

Related literature

For the analgesic properties of pyrazolones, see: Mehlisch (1983[Mehlisch, D. R. (1983). Am. J. Med. 75, 47-52.]); Schnitzer (2003[Schnitzer, T. (2003). Eur. J. Anaesthesiol. Suppl. 28, 13-7.]). For the biological activity of some pyrazolone derivatives, see: Pavlov et al. (1998[Pavlov, P. T., Goleneva, A. F., Lesnov, A. E. & Prokhorova, T. S. (1998). Pharm. Chem. J. 32, 370-372.]). For the pharmacological properties of pyrazolone deriavtives, see: Kees et al. (1996[Kees, K. L., Fitzgerald, J. J. Jr, Steiner, K. E., Mattes, J. F., Mihan, B., Tosi, T., Mondoro, D. & McCalebr, M. L. (1996). J. Med. Chem. 39, 3920-3928.]). For related structures, see: Belmar et al. (2006a[Belmar, J., Jiménez, C., Ortiz, L., Garland, M. T. & Baggio, R. (2006a). Acta Cryst. C62, o76-o78.],b[Belmar, J., Jiménez, C., Ruiz-Pérez, C., Delgado, F. S. & Baggio, R. (2006b). Acta Cryst. C62, o599-o601.]); Pérez et al. (2005[Pérez, F. R., Belmar, J., Jiménez, C., Moreno, Y., Hermosilla, P. & Baggio, R. (2005). Acta Cryst. C61, m318-m320.]). For metal complexes, see: Hyun-Shin et al. (2008[Hyun-Shin, L., Ji-Hyun, S., Moon, K. C., Young-Kwan, K. & Yunkyoung, H. (2008). J. Phys. Chem. Solids, 69, 1305-1309.]); Gallardo et al. (2004[Gallardo, H., Meyer, E., Bortoluzzi, A. J., Molin, F. & Mangrich, A. S. (2004). Inorg. Chim. Acta, 357, 505-512.]); Meyer et al. (1998[Meyer, E., Zucco, C. & Gallardo, H. (1998). J. Mater. Chem. 8, 1351-1354.]). For the synthesis of pyrazolones, see: Nakagawa et al. (2006[Nakagawa, H., Ohyama, R., Kimata, A., Suzuki, T. & Miyata, N. (2006). Bioorg. Med. Chem. Lett. 16, 5939-5942.]); Belmar et al. (2001[Belmar, J., Alderete, J., Zuñiga, C., Jimenez, C., Jimenez, V., Núñez, H., Grandy, R. & Yori, A. (2001). Bol. Soc. Chil. Quim. 46, 459-470.]); Bartulín et al. (1994[Bartulín, J., Belmar, J., Gallardo, H. & León, G. (1994). J. Heterocycl. Chem. 31, 561-563.]). For hydrogen-bond motifs, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data
  • C10H7F3N2O

  • Mr = 228.18

  • Monoclinic, P 21 /c

  • a = 5.8409 (5) Å

  • b = 15.2454 (14) Å

  • c = 11.2291 (17) Å

  • β = 92.403 (9)°

  • V = 999.0 (2) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.14 mm−1

  • T = 293 K

  • 0.46 × 0.40 × 0.20 mm

Data collection
  • Enraf–Nonius CAD-4 diffractometer

  • Absorption correction: none

  • 2262 measured reflections

  • 2157 independent reflections

  • 1141 reflections with I > 2σ(I)

  • Rint = 0.024

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

Refinement
  • R[F2 > 2σ(F2)] = 0.060

  • wR(F2) = 0.188

  • S = 1.03

  • 2157 reflections

  • 173 parameters

  • 81 restraints

  • H-atom parameters constrained

  • Δρmax = 0.30 e Å−3

  • Δρmin = −0.32 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N2—H2⋯O1i 0.88 1.89 2.667 (3) 146
Symmetry code: (i) [x, -y+{\script{3\over 2}}, z-{\script{1\over 2}}].

Data collection: CAD-4 Software (Enraf–Nonius, 1989[Enraf-Nonius (1989). CAD-4 Software. Enraf-Nonius, Delft, The Netherlands.]); cell refinement: SET4 in CAD-4 Software; data reduction: HELENA (Spek, 1996[Spek, A. L. (1996). HELENA. University of Utrecht, The Netherlands.]); 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: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

The pyrazolone analgesics (such as phenylbutazone) have effects similar to those of aspirin. They were commonly used to treat rheumatoid arthritis and has been the focus of medicinal chemists for over last 100 years because of the outstanding pharmacological properties shown by several of its derivatives (Kees et al., 1996). The interest in such compounds, pyrazolone derivative, arises from the fact that the incorporation of heteroatoms can result an ancillary ligand to study their photoactive lanthanide complexes. These compounds possess several sites for substitution, allowing for a systematic analysis of their effects on the photo optical properties. Particulary the luminescence properties of the Eu and Tb complexes.

The molecular structure of (I) consists of a phenyl group bonded to 2-N of the dihydropyrazole heterocyclic ring (Fig. 1). These rings are twisted with respect to each other and the dihedral angle between the mean plane is 33.0 (1)°.The molecules are linked into chains by one intermolecular N—H···O hydrogen bond. Atoms N2 in the molecules at (x,y,z) acts as hydrogen bonds donor vía atom H2 to atoms O1 at (-x, 3/2+y, -1-z) so generating by translation one C(5) chains running parallel to [001] direction (Bernstein et al., 1995), (Fig. 2, Table 1) and the crystal structure is reinforced by a weak face-to-face π-π stacking interactions between phenyl rings with the centroid-centroid distance of 3.881 (2) Å.

Related literature top

For the analgesic properties of pyrazolones, see: Mehlisch (1983); Schnitzer (2003). For the biological activity of some pyrazolone derivatives, see: Pavlov et al. (1998). For the pharmacological properties of pyrazolone deriavtives, see: Kees et al. (1996). For related structures, see: Belmar et al. (2006a,b); Pérez et al. (2005). For metal complexes, see: Hyun-Shin et al. (2008); Gallardo et al. (2004); Meyer et al. (1998). For the synthesis of pyrazolones, see: Nakagawa et al. (2006); Belmar et al. (2001); Bartulín et al. (1994). For hydrogen-bond motifs, see: Bernstein et al. (1995).

Refinement top

All non-H atoms were refined with anisotropic displacement parameters. HAr atoms were placed at their idealized positions with distances of 0.93 Å and Ueq fixed at 1.2 Uiso of the preceding atom. H atom attached to N atom was located from Fourier difference map and treated with riding model. Fluorine atoms are disordered over two alternative positions with refined site occupancies of 0.768 (11) and 0.232 (11).

Computing details top

Data collection: CAD-4 Software (Enraf–Nonius, 1989); cell refinement: SET4 in CAD-4 Software (Enraf–Nonius, 1989); data reduction: HELENA (Spek, 1996); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) with labeling scheme. Displacement ellipsoids are shown at the 40% probability level.
[Figure 2] Fig. 2. Part of the crystal structure of (I), showing the formation of a C(5) chain pattern. [Symmetry code: (i) x,-y+3/2,z-1/2]
2-Phenyl-5-(trifluoromethyl)pyrazol-3(2H)-one top
Crystal data top
C10H7F3N2OF(000) = 464
Mr = 228.18Dx = 1.517 Mg m3
Monoclinic, P21/cMelting point = 464–465 K
Hall symbol: -P 2ybcMo Kα radiation, λ = 0.71073 Å
a = 5.8409 (5) ÅCell parameters from 25 reflections
b = 15.2454 (14) Åθ = 3.2–13.8°
c = 11.2291 (17) ŵ = 0.14 mm1
β = 92.403 (9)°T = 293 K
V = 999.0 (2) Å3Irregular, colourless
Z = 40.46 × 0.40 × 0.20 mm
Data collection top
Enraf–Nonius CAD-4
diffractometer
Rint = 0.024
Radiation source: fine-focus sealed tubeθmax = 27.0°, θmin = 2.3°
Graphite monochromatorh = 77
ω–2θ scansk = 190
2262 measured reflectionsl = 140
2157 independent reflections3 standard reflections every 200 reflections
1141 reflections with I > 2σ(I) 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)] = 0.060Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.188H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.0843P)2 + 0.3445P]
where P = (Fo2 + 2Fc2)/3
2157 reflections(Δ/σ)max = 0.001
173 parametersΔρmax = 0.30 e Å3
81 restraintsΔρmin = 0.32 e Å3
Crystal data top
C10H7F3N2OV = 999.0 (2) Å3
Mr = 228.18Z = 4
Monoclinic, P21/cMo Kα radiation
a = 5.8409 (5) ŵ = 0.14 mm1
b = 15.2454 (14) ÅT = 293 K
c = 11.2291 (17) Å0.46 × 0.40 × 0.20 mm
β = 92.403 (9)°
Data collection top
Enraf–Nonius CAD-4
diffractometer
Rint = 0.024
2262 measured reflections3 standard reflections every 200 reflections
2157 independent reflections intensity decay: 1%
1141 reflections with I > 2σ(I)
Refinement top
R[F2 > 2σ(F2)] = 0.06081 restraints
wR(F2) = 0.188H-atom parameters constrained
S = 1.03Δρmax = 0.30 e Å3
2157 reflectionsΔρmin = 0.32 e Å3
173 parameters
Special details top

Experimental. The title compound was synthesized by the condensation of ethyl 4,4,4-trifluoroacetoacetate (5.0?g, 27.2?mmol) in acetic acid (50?ml) with phenylhydrazine (2.9?g, 27.2?mmol) which was added drop wise, with stirring for 3?h. The solvent was removed by evaporation; resulting crude solid was extracted with AcOEt. The organic layer was washed with saturated aqueous NaHCO3 and water, then brine, and evaporation the solvent. The compound, obtained as colorless single crystals, was recrystallized using ethylacetate and n-hexane (2:1) and was suitable for X-ray structure determination. Yield 76% mp: 191–192 °C, lit. 195–196 °C (Nakagawa et al., 2006). 1H-NMR (DMSO, 400?MHz, d, p.p.m.) 12,42 (1H, s), 7,70 (2H, d, J = 8?Hz), 7,49 (2H, t, J = 8?Hz), 7,36 (1H, t, J = 8?Hz), 5,92 (1H, s). 13C-NMR (DMSO, 400?MHz, d, p.p.m.) 153,68 (C5), 140,21 (C3), 13,70 (C6), 129,07 (C10; C8), 127,18 (C9), 122,25 (C11; C7), 119,98 (C12), 85,53 (C4).

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
N10.2789 (5)0.78258 (17)0.98039 (19)0.0486 (7)
N20.3999 (5)0.73266 (19)0.90418 (19)0.0534 (7)
H20.37290.74050.82700.064*
C30.5425 (6)0.6863 (2)0.9721 (3)0.0535 (8)
C40.5221 (6)0.7045 (2)1.0923 (3)0.0567 (9)
H40.60520.68011.15660.068*
C50.3528 (6)0.7661 (2)1.0950 (2)0.0523 (8)
C60.1101 (5)0.8436 (2)0.9370 (2)0.0471 (8)
C70.1383 (6)0.8843 (2)0.8282 (2)0.0582 (9)
H70.26710.87300.78470.070*
C80.0280 (7)0.9420 (3)0.7854 (3)0.0730 (11)
H80.01110.96940.71230.088*
C90.2193 (7)0.9594 (3)0.8499 (4)0.0745 (11)
H90.33040.99830.82040.089*
C100.2439 (6)0.9189 (3)0.9575 (3)0.0691 (10)
H100.37150.93091.00160.083*
C110.0805 (6)0.8604 (2)1.0010 (3)0.0583 (9)
H110.09940.83231.07350.070*
C120.7009 (8)0.6240 (3)0.9172 (3)0.0712 (11)
F10.7641 (13)0.6502 (4)0.8115 (4)0.118 (3)0.768 (11)
F1'0.617 (3)0.5831 (17)0.826 (2)0.129 (8)0.232 (11)
F20.8938 (12)0.6159 (7)0.9809 (5)0.129 (3)0.768 (11)
F2'0.884 (4)0.6549 (11)0.882 (3)0.141 (9)0.232 (11)
F30.6134 (13)0.5470 (4)0.9008 (9)0.144 (3)0.768 (11)
F3'0.760 (5)0.5604 (14)0.9906 (13)0.104 (6)0.232 (11)
O10.2602 (4)0.81041 (16)1.18269 (16)0.0686 (8)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0599 (16)0.0617 (17)0.0244 (11)0.0019 (14)0.0042 (10)0.0008 (11)
N20.0666 (17)0.0714 (18)0.0225 (11)0.0001 (14)0.0044 (11)0.0034 (11)
C30.062 (2)0.062 (2)0.0374 (16)0.0015 (17)0.0057 (15)0.0011 (15)
C40.068 (2)0.068 (2)0.0336 (15)0.0072 (19)0.0006 (14)0.0062 (15)
C50.070 (2)0.063 (2)0.0242 (14)0.0023 (18)0.0033 (13)0.0040 (13)
C60.0554 (19)0.0511 (18)0.0343 (15)0.0052 (16)0.0026 (13)0.0028 (13)
C70.072 (2)0.067 (2)0.0360 (15)0.0042 (19)0.0003 (15)0.0052 (15)
C80.093 (3)0.068 (3)0.056 (2)0.011 (2)0.015 (2)0.0164 (18)
C90.075 (3)0.063 (2)0.083 (3)0.001 (2)0.022 (2)0.005 (2)
C100.059 (2)0.073 (2)0.075 (2)0.001 (2)0.0004 (18)0.004 (2)
C110.062 (2)0.066 (2)0.0470 (18)0.0056 (19)0.0017 (16)0.0011 (16)
C120.078 (3)0.083 (3)0.054 (2)0.010 (2)0.018 (2)0.003 (2)
F10.142 (6)0.152 (5)0.064 (3)0.052 (4)0.050 (3)0.008 (3)
F1'0.083 (11)0.172 (19)0.129 (14)0.035 (11)0.038 (10)0.112 (12)
F20.100 (4)0.187 (7)0.099 (4)0.068 (4)0.016 (3)0.030 (4)
F2'0.105 (13)0.127 (13)0.20 (2)0.035 (10)0.083 (14)0.071 (15)
F30.164 (6)0.077 (3)0.197 (8)0.008 (3)0.088 (6)0.041 (4)
F3'0.133 (15)0.104 (11)0.074 (8)0.059 (10)0.003 (9)0.004 (8)
O10.0983 (19)0.0804 (17)0.0276 (11)0.0248 (15)0.0078 (11)0.0044 (10)
Geometric parameters (Å, º) top
N1—C51.363 (3)C8—C91.382 (6)
N1—N21.365 (3)C8—H80.9300
N1—C61.426 (4)C9—C101.371 (5)
N2—C31.312 (4)C9—H90.9300
N2—H20.8825C10—C111.381 (5)
C3—C41.388 (4)C10—H100.9300
C3—C121.479 (5)C11—H110.9300
C4—C51.366 (5)C12—F2'1.247 (14)
C4—H40.9300C12—F1'1.279 (13)
C5—O11.327 (4)C12—F31.291 (7)
C6—C111.374 (4)C12—F3'1.309 (13)
C6—C71.387 (4)C12—F21.315 (6)
C7—C81.381 (5)C12—F11.320 (5)
C7—H70.9300
C5—N1—N2109.7 (3)C9—C8—H8119.6
C5—N1—C6129.0 (2)C10—C9—C8119.5 (4)
N2—N1—C6121.2 (2)C10—C9—H9120.3
C3—N2—N1105.6 (2)C8—C9—H9120.3
C3—N2—H2136.6C9—C10—C11120.4 (4)
N1—N2—H2117.7C9—C10—H10119.8
N2—C3—C4112.3 (3)C11—C10—H10119.8
N2—C3—C12119.8 (3)C6—C11—C10119.9 (3)
C4—C3—C12127.9 (3)C6—C11—H11120.1
C5—C4—C3104.5 (3)C10—C11—H11120.1
C5—C4—H4127.7F2'—C12—F1'103.5 (9)
C3—C4—H4127.7F2'—C12—F3'105.9 (9)
O1—C5—N1119.0 (3)F1'—C12—F3'103.0 (9)
O1—C5—C4133.2 (3)F3—C12—F2108.5 (5)
N1—C5—C4107.9 (3)F3—C12—F1105.8 (5)
C11—C6—C7120.4 (3)F2—C12—F1104.6 (5)
C11—C6—N1120.4 (3)F2'—C12—C3116.7 (8)
C7—C6—N1119.2 (3)F1'—C12—C3114.9 (7)
C8—C7—C6118.9 (3)F3—C12—C3113.1 (4)
C8—C7—H7120.5F3'—C12—C3111.6 (7)
C6—C7—H7120.5F2—C12—C3111.8 (4)
C7—C8—C9120.8 (3)F1—C12—C3112.5 (4)
C7—C8—H8119.6
C5—N1—N2—C30.6 (4)C6—C7—C8—C90.3 (5)
C6—N1—N2—C3178.3 (3)C7—C8—C9—C100.0 (6)
N1—N2—C3—C40.6 (4)C8—C9—C10—C110.7 (6)
N1—N2—C3—C12179.7 (3)C7—C6—C11—C100.7 (5)
N2—C3—C4—C50.4 (4)N1—C6—C11—C10179.4 (3)
C12—C3—C4—C5180.0 (4)C9—C10—C11—C61.1 (5)
N2—N1—C5—O1178.1 (3)N2—C3—C12—F2'84.0 (18)
C6—N1—C5—O10.6 (5)C4—C3—C12—F2'95.6 (18)
N2—N1—C5—C40.4 (4)N2—C3—C12—F1'37.5 (17)
C6—N1—C5—C4177.9 (3)C4—C3—C12—F1'143.0 (17)
C3—C4—C5—O1178.1 (4)N2—C3—C12—F388.1 (7)
C3—C4—C5—N10.0 (4)C4—C3—C12—F392.3 (7)
C5—N1—C6—C1135.3 (5)N2—C3—C12—F3'154.2 (17)
N2—N1—C6—C11147.5 (3)C4—C3—C12—F3'26.3 (18)
C5—N1—C6—C7146.0 (3)N2—C3—C12—F2149.0 (7)
N2—N1—C6—C731.2 (4)C4—C3—C12—F230.5 (9)
C11—C6—C7—C80.0 (5)N2—C3—C12—F131.7 (7)
N1—C6—C7—C8178.7 (3)C4—C3—C12—F1147.9 (5)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2···O1i0.881.892.667 (3)146
Symmetry code: (i) x, y+3/2, z1/2.

Experimental details

Crystal data
Chemical formulaC10H7F3N2O
Mr228.18
Crystal system, space groupMonoclinic, P21/c
Temperature (K)293
a, b, c (Å)5.8409 (5), 15.2454 (14), 11.2291 (17)
β (°) 92.403 (9)
V3)999.0 (2)
Z4
Radiation typeMo Kα
µ (mm1)0.14
Crystal size (mm)0.46 × 0.40 × 0.20
Data collection
DiffractometerEnraf–Nonius CAD-4
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
2262, 2157, 1141
Rint0.024
(sin θ/λ)max1)0.638
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.060, 0.188, 1.03
No. of reflections2157
No. of parameters173
No. of restraints81
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.30, 0.32

Computer programs: , SET4 in CAD-4 Software (Enraf–Nonius, 1989), HELENA (Spek, 1996), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2···O1i0.881.892.667 (3)145.9
Symmetry code: (i) x, y+3/2, z1/2.
 

Acknowledgements

The authors are grateful to the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), the Fundação de Apoio à Pesquisa Científica e Tecnológica do Estado de Santa Catarina (FAPESC), the Instituto Nacional de Ciência e Tecnologia (INCT-cat) and the Financiadora de Estudos e Projetos (FINEP) for financial assistance.

References

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Volume 65| Part 8| August 2009| Pages o2040-o2041
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