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

Gallardo, H.; Girotto, E.; Bortoluzzi, A.J.; Terra, G.G.

doi:10.1107/S1600536809029419

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

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

doi:10.1107/S1600536809029419

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

Hugo Gallardo,^a ^* Edivandro Girotto,^a Adailton J. Bortoluzzi ^a and Geovana G. Terra ^a

^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 π–π 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 ); 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 ).

Experimental

Crystal data

C₁₀H₇F₃N₂O
M_r = 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)
R_int = 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
Δρ_max = 0.30 e Å⁻³
Δρ_min = −0.32 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	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 ); cell refinement: SET4 in CAD-4 Software; 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.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809029419/bx2225sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809029419/bx2225Isup2.hkl

checkCIF report

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).

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

	Fig. 1. The molecular structure of (I) with labeling scheme. Displacement ellipsoids are shown at the 40% probability level.
	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

C₁₀H₇F₃N₂O	F(000) = 464
M_r = 228.18	D_x = 1.517 Mg m⁻³
Monoclinic, P2₁/c	Melting point = 464–465 K
Hall symbol: -P 2ybc	Mo Kα radiation, λ = 0.71073 Å
a = 5.8409 (5) Å	Cell parameters from 25 reflections
b = 15.2454 (14) Å	θ = 3.2–13.8°
c = 11.2291 (17) Å	µ = 0.14 mm⁻¹
β = 92.403 (9)°	T = 293 K
V = 999.0 (2) Å³	Irregular, colourless
Z = 4	0.46 × 0.40 × 0.20 mm

Data collection top

Enraf–Nonius CAD-4 diffractometer	R_int = 0.024
Radiation source: fine-focus sealed tube	θ_max = 27.0°, θ_min = 2.3°
Graphite monochromator	h = −7→7
ω–2θ scans	k = −19→0
2262 measured reflections	l = −14→0
2157 independent reflections	3 standard reflections every 200 reflections
1141 reflections with I > 2σ(I)	intensity decay: 1%

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.060	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.188	H-atom parameters constrained
S = 1.03	w = 1/[σ²(F_o²) + (0.0843P)² + 0.3445P] where P = (F_o² + 2F_c²)/3
2157 reflections	(Δ/σ)_max = 0.001
173 parameters	Δρ_max = 0.30 e Å⁻³
81 restraints	Δρ_min = −0.32 e Å⁻³

Crystal data top

C₁₀H₇F₃N₂O	V = 999.0 (2) Å³
M_r = 228.18	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 5.8409 (5) Å	µ = 0.14 mm⁻¹
b = 15.2454 (14) Å	T = 293 K
c = 11.2291 (17) Å	0.46 × 0.40 × 0.20 mm
β = 92.403 (9)°

Data collection top

Enraf–Nonius CAD-4 diffractometer	R_int = 0.024
2262 measured reflections	3 standard reflections every 200 reflections
2157 independent reflections	intensity decay: 1%
1141 reflections with I > 2σ(I)

Refinement top

R[F² > 2σ(F²)] = 0.060	81 restraints
wR(F²) = 0.188	H-atom parameters constrained
S = 1.03	Δρ_max = 0.30 e Å⁻³
2157 reflections	Δρ_min = −0.32 e Å⁻³
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

	x	y	z	U_iso*/U_eq	Occ. (<1)
N1	0.2789 (5)	0.78258 (17)	0.98039 (19)	0.0486 (7)
N2	0.3999 (5)	0.73266 (19)	0.90418 (19)	0.0534 (7)
H2	0.3729	0.7405	0.8270	0.064*
C3	0.5425 (6)	0.6863 (2)	0.9721 (3)	0.0535 (8)
C4	0.5221 (6)	0.7045 (2)	1.0923 (3)	0.0567 (9)
H4	0.6052	0.6801	1.1566	0.068*
C5	0.3528 (6)	0.7661 (2)	1.0950 (2)	0.0523 (8)
C6	0.1101 (5)	0.8436 (2)	0.9370 (2)	0.0471 (8)
C7	0.1383 (6)	0.8843 (2)	0.8282 (2)	0.0582 (9)
H7	0.2671	0.8730	0.7847	0.070*
C8	−0.0280 (7)	0.9420 (3)	0.7854 (3)	0.0730 (11)
H8	−0.0111	0.9694	0.7123	0.088*
C9	−0.2193 (7)	0.9594 (3)	0.8499 (4)	0.0745 (11)
H9	−0.3304	0.9983	0.8204	0.089*
C10	−0.2439 (6)	0.9189 (3)	0.9575 (3)	0.0691 (10)
H10	−0.3715	0.9309	1.0016	0.083*
C11	−0.0805 (6)	0.8604 (2)	1.0010 (3)	0.0583 (9)
H11	−0.0994	0.8323	1.0735	0.070*
C12	0.7009 (8)	0.6240 (3)	0.9172 (3)	0.0712 (11)
F1	0.7641 (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)
F2	0.8938 (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)
F3	0.6134 (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)
O1	0.2602 (4)	0.81041 (16)	1.18269 (16)	0.0686 (8)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0599 (16)	0.0617 (17)	0.0244 (11)	0.0019 (14)	0.0042 (10)	−0.0008 (11)
N2	0.0666 (17)	0.0714 (18)	0.0225 (11)	0.0001 (14)	0.0044 (11)	−0.0034 (11)
C3	0.062 (2)	0.062 (2)	0.0374 (16)	0.0015 (17)	0.0057 (15)	0.0011 (15)
C4	0.068 (2)	0.068 (2)	0.0336 (15)	0.0072 (19)	0.0006 (14)	0.0062 (15)
C5	0.070 (2)	0.063 (2)	0.0242 (14)	−0.0023 (18)	0.0033 (13)	0.0040 (13)
C6	0.0554 (19)	0.0511 (18)	0.0343 (15)	−0.0052 (16)	−0.0026 (13)	−0.0028 (13)
C7	0.072 (2)	0.067 (2)	0.0360 (15)	−0.0042 (19)	0.0003 (15)	0.0052 (15)
C8	0.093 (3)	0.068 (3)	0.056 (2)	−0.011 (2)	−0.015 (2)	0.0164 (18)
C9	0.075 (3)	0.063 (2)	0.083 (3)	0.001 (2)	−0.022 (2)	0.005 (2)
C10	0.059 (2)	0.073 (2)	0.075 (2)	0.001 (2)	−0.0004 (18)	−0.004 (2)
C11	0.062 (2)	0.066 (2)	0.0470 (18)	−0.0056 (19)	0.0017 (16)	0.0011 (16)
C12	0.078 (3)	0.083 (3)	0.054 (2)	0.010 (2)	0.018 (2)	−0.003 (2)
F1	0.142 (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)
F2	0.100 (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)
F3	0.164 (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)
O1	0.0983 (19)	0.0804 (17)	0.0276 (11)	0.0248 (15)	0.0078 (11)	−0.0044 (10)

Geometric parameters (Å, º) top

N1—C5	1.363 (3)	C8—C9	1.382 (6)
N1—N2	1.365 (3)	C8—H8	0.9300
N1—C6	1.426 (4)	C9—C10	1.371 (5)
N2—C3	1.312 (4)	C9—H9	0.9300
N2—H2	0.8825	C10—C11	1.381 (5)
C3—C4	1.388 (4)	C10—H10	0.9300
C3—C12	1.479 (5)	C11—H11	0.9300
C4—C5	1.366 (5)	C12—F2'	1.247 (14)
C4—H4	0.9300	C12—F1'	1.279 (13)
C5—O1	1.327 (4)	C12—F3	1.291 (7)
C6—C11	1.374 (4)	C12—F3'	1.309 (13)
C6—C7	1.387 (4)	C12—F2	1.315 (6)
C7—C8	1.381 (5)	C12—F1	1.320 (5)
C7—H7	0.9300

C5—N1—N2	109.7 (3)	C9—C8—H8	119.6
C5—N1—C6	129.0 (2)	C10—C9—C8	119.5 (4)
N2—N1—C6	121.2 (2)	C10—C9—H9	120.3
C3—N2—N1	105.6 (2)	C8—C9—H9	120.3
C3—N2—H2	136.6	C9—C10—C11	120.4 (4)
N1—N2—H2	117.7	C9—C10—H10	119.8
N2—C3—C4	112.3 (3)	C11—C10—H10	119.8
N2—C3—C12	119.8 (3)	C6—C11—C10	119.9 (3)
C4—C3—C12	127.9 (3)	C6—C11—H11	120.1
C5—C4—C3	104.5 (3)	C10—C11—H11	120.1
C5—C4—H4	127.7	F2'—C12—F1'	103.5 (9)
C3—C4—H4	127.7	F2'—C12—F3'	105.9 (9)
O1—C5—N1	119.0 (3)	F1'—C12—F3'	103.0 (9)
O1—C5—C4	133.2 (3)	F3—C12—F2	108.5 (5)
N1—C5—C4	107.9 (3)	F3—C12—F1	105.8 (5)
C11—C6—C7	120.4 (3)	F2—C12—F1	104.6 (5)
C11—C6—N1	120.4 (3)	F2'—C12—C3	116.7 (8)
C7—C6—N1	119.2 (3)	F1'—C12—C3	114.9 (7)
C8—C7—C6	118.9 (3)	F3—C12—C3	113.1 (4)
C8—C7—H7	120.5	F3'—C12—C3	111.6 (7)
C6—C7—H7	120.5	F2—C12—C3	111.8 (4)
C7—C8—C9	120.8 (3)	F1—C12—C3	112.5 (4)
C7—C8—H8	119.6

C5—N1—N2—C3	0.6 (4)	C6—C7—C8—C9	0.3 (5)
C6—N1—N2—C3	178.3 (3)	C7—C8—C9—C10	0.0 (6)
N1—N2—C3—C4	−0.6 (4)	C8—C9—C10—C11	−0.7 (6)
N1—N2—C3—C12	179.7 (3)	C7—C6—C11—C10	−0.7 (5)
N2—C3—C4—C5	0.4 (4)	N1—C6—C11—C10	−179.4 (3)
C12—C3—C4—C5	180.0 (4)	C9—C10—C11—C6	1.1 (5)
N2—N1—C5—O1	178.1 (3)	N2—C3—C12—F2'	84.0 (18)
C6—N1—C5—O1	0.6 (5)	C4—C3—C12—F2'	−95.6 (18)
N2—N1—C5—C4	−0.4 (4)	N2—C3—C12—F1'	−37.5 (17)
C6—N1—C5—C4	−177.9 (3)	C4—C3—C12—F1'	143.0 (17)
C3—C4—C5—O1	−178.1 (4)	N2—C3—C12—F3	−88.1 (7)
C3—C4—C5—N1	0.0 (4)	C4—C3—C12—F3	92.3 (7)
C5—N1—C6—C11	−35.3 (5)	N2—C3—C12—F3'	−154.2 (17)
N2—N1—C6—C11	147.5 (3)	C4—C3—C12—F3'	26.3 (18)
C5—N1—C6—C7	146.0 (3)	N2—C3—C12—F2	149.0 (7)
N2—N1—C6—C7	−31.2 (4)	C4—C3—C12—F2	−30.5 (9)
C11—C6—C7—C8	0.0 (5)	N2—C3—C12—F1	31.7 (7)
N1—C6—C7—C8	178.7 (3)	C4—C3—C12—F1	−147.9 (5)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2···O1ⁱ	0.88	1.89	2.667 (3)	146

Symmetry code: (i) x, −y+3/2, z−1/2.

Experimental details

Crystal data
Chemical formula	C₁₀H₇F₃N₂O
M_r	228.18
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	5.8409 (5), 15.2454 (14), 11.2291 (17)
β (°)	92.403 (9)
V (Å³)	999.0 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.14
Crystal size (mm)	0.46 × 0.40 × 0.20

Data collection
Diffractometer	Enraf–Nonius CAD-4 diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	2262, 2157, 1141
R_int	0.024
(sin θ/λ)_max (Å⁻¹)	0.638

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.060, 0.188, 1.03
No. of reflections	2157
No. of parameters	173
No. of restraints	81
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	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···A	D—H	H···A	D···A	D—H···A
N2—H2···O1ⁱ	0.88	1.89	2.667 (3)	145.9

Symmetry code: (i) x, −y+3/2, z−1/2.

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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