1-Methyl-3-trifluoro­methyl-1H-pyrazol-5-ol

Xu, J.; Cheng, W.; Yan, J.; Quan, G.

doi:10.1107/S1600536809035624

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 65| Part 10| October 2009| Page o2377

doi:10.1107/S1600536809035624

Open

access

1-Methyl-3-trifluoromethyl-1H-pyrazol-5-ol

Jia-ying Xu,^a ^* Wei-hua Cheng,^b Jin-long Yan ^a and Gui-xiang Quan ^a

^aDepartment of Applied Chemistry, College of Chemical and Biological Engineering, Yancheng Institute of Technology, Yinbing Road No. 9 Yancheng, Yancheng 224051, People's Republic of China, and ^bDepartment of Chemical Engineering, Yancheng College of Textile Technology, Liberation Road S. No. 265 Yancheng, Yancheng 224005, People's Republic of China
^*Correspondence e-mail: xujiaying-1984@163.com

(Received 2 September 2009; accepted 3 September 2009; online 9 September 2009)

In the title compound, C₅H₅F₃N₂O, the F atoms are disordered over two sets of sites in a 0.64 (3):0.36 (3) ratio. In the crystal structure, O—H⋯N hydrogen bonds link the molecules into chains and a short C—H⋯F contact also occurs.

Related literature

For background to fluorinated heterocycles, see: Marcos & Martins (2003 ). For bond-length data, see: Allen et al. (1987 ).

Experimental

Crystal data

C₅H₅F₃N₂O
M_r = 166.11
Monoclinic, P 2₁ /c
a = 7.5500 (15) Å
b = 8.3530 (17) Å
c = 11.371 (2) Å
β = 104.72 (3)°
V = 693.6 (2) Å³
Z = 4
Mo Kα radiation
μ = 0.17 mm⁻¹
T = 293 K
0.20 × 0.10 × 0.10 mm

Data collection

Enraf–Nonius CAD-4 diffractometer
Absorption correction: ψ scan (North et al., 1968 ) T_min = 0.968, T_max = 0.984
1357 measured reflections
1259 independent reflections
856 reflections with I > 2σ(I)
R_int = 0.041
3 standard reflections every 200 reflections intensity decay: 1%

Refinement

R[F² > 2σ(F²)] = 0.050
wR(F²) = 0.168
S = 1.00
1259 reflections
130 parameters
36 restraints
H-atom parameters constrained
Δρ_max = 0.20 e Å⁻³
Δρ_min = −0.21 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O—H0A⋯N1ⁱ	0.85	1.85	2.698 (3)	176
C5—H5B⋯F3′ⁱⁱ	0.96	2.55	3.185 (12)	124
Symmetry codes: (i) $[x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ ; (ii) -x+1, -y+1, -z.

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994 ); cell refinement: CAD-4 EXPRESS; 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) and ORTEP-3 (Farrugia, 1997 ); software used to prepare material for publication: PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809035624/hb5087sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809035624/hb5087Isup2.hkl

checkCIF report

Comment top

As part of the ongoing study of polyfluorinated heterocycles (Marcos & Martins, 2003), we report herein the crystal structure of the title compound.

In the molecule of the title compound (Fig 1), the bond lengths (Allen et al., 1987) and angles are within normal ranges. Ring A (C4-C9) is, of course, planar. The intramolecular C-H···O hydrogen bond (Table 1) results in the formation of a five-membered ring B (O1/C1-C3/H1A), having envelope conformation with C2 atom displaced by -0.668 (3) Å from the plane of the other ring atoms.

In the crystal structure, intermolecular O—H···N hydrogen bonds (Table 1) link the molecules (Fig. 2), in which they may be effective in the stabilization of the structure.

Related literature top

For background on fluorinated heterocycles, see: Marcos & Martins (2003). For bond-length data, see: Allen et al. (1987).

For related literature, see: Farrugia (1997).

Experimental top

4,4-Diethoxy-1,1,1-trifluorobut-3-en-2-one (2 mmol) was added to a stirred solution of hydrazine (2.2 mmol) at room temperature in ethanol (15 ml). The mixture was stirred under reflux for 24 h. The solvent was evaporated and to the residue was added H2O (10 ml) and the organic phase were extract with dichloromethane (15 ml). The organic extract was dried (Na₂SO₄) and the solvent was removed under reduced pressure to obtain the title compound (yield; 25%, m.p. 446 K). Colourless blocks of (I) were obtained by slow evaporation of an ethyl acetate solution.

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: PLATON (Spek, 2009).

Figures top

	Fig. 1. The molecular structure of (I).
	Fig. 2. A partial packing diagram of (I). Hydrogen bonds are shown as dashed lines.

1-Methyl-3-trifluoromethyl-1H-pyrazol-5-ol top

Crystal data top

C₅H₅F₃N₂O	F(000) = 336
M_r = 166.11	D_x = 1.591 Mg m⁻³
Monoclinic, P2₁/c	Melting point: 446 K
Hall symbol: -P 2ybc	Mo Kα radiation, λ = 0.71073 Å
a = 7.5500 (15) Å	Cell parameters from 25 reflections
b = 8.3530 (17) Å	θ = 9–13°
c = 11.371 (2) Å	µ = 0.17 mm⁻¹
β = 104.72 (3)°	T = 293 K
V = 693.6 (2) Å³	Block, colourless
Z = 4	0.20 × 0.10 × 0.10 mm

Data collection top

Enraf–Nonius CAD-4 diffractometer	856 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.041
Graphite monochromator	θ_max = 25.3°, θ_min = 2.8°
ω/2θ scans	h = 0→9
Absorption correction: ψ scan (North et al., 1968)	k = 0→10
T_min = 0.968, T_max = 0.984	l = −13→13
1357 measured reflections	3 standard reflections every 200 reflections
1259 independent reflections	intensity decay: 1%

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.050	H-atom parameters constrained
wR(F²) = 0.168	w = 1/[σ²(F_o²) + (0.1P)² + 0.12P] where P = (F_o² + 2F_c²)/3
S = 1.00	(Δ/σ)_max < 0.001
1259 reflections	Δρ_max = 0.20 e Å⁻³
130 parameters	Δρ_min = −0.21 e Å⁻³
36 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.062 (13)

Crystal data top

C₅H₅F₃N₂O	V = 693.6 (2) Å³
M_r = 166.11	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 7.5500 (15) Å	µ = 0.17 mm⁻¹
b = 8.3530 (17) Å	T = 293 K
c = 11.371 (2) Å	0.20 × 0.10 × 0.10 mm
β = 104.72 (3)°

Data collection top

Enraf–Nonius CAD-4 diffractometer	856 reflections with I > 2σ(I)
Absorption correction: ψ scan (North et al., 1968)	R_int = 0.041
T_min = 0.968, T_max = 0.984	3 standard reflections every 200 reflections
1357 measured reflections	intensity decay: 1%
1259 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.050	36 restraints
wR(F²) = 0.168	H-atom parameters constrained
S = 1.00	Δρ_max = 0.20 e Å⁻³
1259 reflections	Δρ_min = −0.21 e Å⁻³
130 parameters

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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

	x	y	z	U_iso*/U_eq	Occ. (<1)
O	0.6146 (3)	0.1822 (3)	0.22551 (16)	0.0812 (8)
H0A	0.5735	0.1988	0.2874	0.097*
N1	0.4722 (3)	0.2582 (3)	−0.08398 (18)	0.0562 (7)
C1	0.1757 (5)	0.3877 (5)	−0.1412 (3)	0.0701 (9)
N2	0.5857 (3)	0.2020 (3)	0.02028 (18)	0.0549 (7)
C2	0.3341 (4)	0.3246 (3)	−0.0489 (2)	0.0540 (8)
C3	0.3563 (4)	0.3122 (4)	0.0765 (2)	0.0609 (8)
H3A	0.2783	0.3492	0.1220	0.073*
C4	0.5184 (4)	0.2333 (4)	0.1169 (2)	0.0585 (8)
C5	0.7551 (4)	0.1216 (5)	0.0201 (3)	0.0697 (9)
H5A	0.8043	0.0723	0.0978	0.105*
H5B	0.8414	0.1981	0.0046	0.105*
H5C	0.7323	0.0411	−0.0422	0.105*
F1	0.0666 (15)	0.2656 (12)	−0.1980 (10)	0.117 (3)	0.64 (3)
F2	0.2287 (15)	0.4689 (17)	−0.2294 (11)	0.107 (3)	0.64 (3)
F3	0.057 (2)	0.458 (3)	−0.0997 (12)	0.093 (5)	0.36 (3)
F3'	0.1113 (17)	0.5237 (14)	−0.0992 (8)	0.103 (2)	0.64 (3)
F2'	0.202 (2)	0.412 (2)	−0.2461 (11)	0.077 (4)	0.36 (3)
F1'	0.0325 (19)	0.309 (3)	−0.157 (2)	0.105 (5)	0.36 (3)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O	0.0761 (14)	0.143 (2)	0.0277 (11)	0.0173 (14)	0.0192 (9)	0.0057 (11)
N1	0.0633 (14)	0.0805 (17)	0.0266 (11)	−0.0061 (12)	0.0150 (10)	−0.0014 (10)
C1	0.075 (2)	0.089 (2)	0.0477 (18)	0.003 (2)	0.0183 (16)	0.0058 (16)
N2	0.0585 (13)	0.0824 (16)	0.0266 (11)	−0.0018 (12)	0.0162 (9)	−0.0031 (10)
C2	0.0632 (17)	0.0676 (18)	0.0346 (13)	−0.0069 (14)	0.0190 (12)	−0.0019 (12)
C3	0.0642 (17)	0.090 (2)	0.0338 (14)	−0.0021 (16)	0.0221 (12)	−0.0070 (13)
C4	0.0606 (17)	0.090 (2)	0.0277 (13)	−0.0054 (16)	0.0164 (12)	−0.0050 (13)
C5	0.0675 (18)	0.100 (2)	0.0454 (16)	0.0037 (18)	0.0219 (14)	−0.0017 (15)
F1	0.096 (4)	0.120 (4)	0.104 (5)	−0.001 (3)	−0.033 (3)	−0.017 (3)
F2	0.118 (4)	0.122 (6)	0.076 (4)	−0.003 (4)	0.016 (3)	0.042 (4)
F3	0.088 (6)	0.120 (10)	0.074 (4)	0.036 (6)	0.027 (4)	−0.009 (6)
F3'	0.112 (5)	0.099 (5)	0.095 (3)	0.028 (4)	0.020 (3)	0.000 (3)
F2'	0.091 (6)	0.114 (8)	0.030 (3)	0.019 (5)	0.024 (3)	0.011 (4)
F1'	0.073 (5)	0.114 (9)	0.110 (8)	−0.029 (5)	−0.008 (5)	0.014 (6)

Geometric parameters (Å, º) top

O—C4	1.334 (3)	C1—C2	1.474 (4)
O—H0A	0.8501	N2—C4	1.348 (3)
N1—C2	1.328 (3)	N2—C5	1.445 (4)
N1—N2	1.358 (3)	C2—C3	1.397 (4)
C1—F1'	1.238 (13)	C3—C4	1.363 (4)
C1—F3	1.257 (12)	C3—H3A	0.9300
C1—F2'	1.274 (12)	C5—H5A	0.9600
C1—F2	1.352 (10)	C5—H5B	0.9600
C1—F1	1.366 (9)	C5—H5C	0.9600
C1—F3'	1.369 (9)

C4—O—H0A	119.2	F1—C1—C2	110.6 (5)
C2—N1—N2	104.6 (2)	F3'—C1—C2	110.2 (5)
F1'—C1—F3	68 (2)	C4—N2—N1	111.1 (2)
F1'—C1—F2'	106.6 (10)	C4—N2—C5	127.5 (2)
F3—C1—F2'	124.7 (11)	N1—N2—C5	121.5 (2)
F1'—C1—F2	124.7 (8)	N1—C2—C3	112.1 (3)
F3—C1—F2	114.7 (14)	N1—C2—C1	119.5 (2)
F2'—C1—F2	23.0 (8)	C3—C2—C1	128.2 (3)
F1'—C1—F1	30.3 (9)	C4—C3—C2	104.2 (2)
F3—C1—F1	97.0 (17)	C4—C3—H3A	127.9
F2'—C1—F1	84.1 (8)	C2—C3—H3A	127.9
F2—C1—F1	106.3 (6)	O—C4—N2	117.6 (3)
F1'—C1—F3'	96.6 (18)	O—C4—C3	134.3 (2)
F3—C1—F3'	29.9 (8)	N2—C4—C3	108.1 (2)
F2'—C1—F3'	110.2 (11)	N2—C5—H5A	109.5
F2—C1—F3'	92.4 (11)	N2—C5—H5B	109.5
F1—C1—F3'	124.0 (11)	H5A—C5—H5B	109.5
F1'—C1—C2	115.8 (7)	N2—C5—H5C	109.5
F3—C1—C2	115.2 (6)	H5A—C5—H5C	109.5
F2'—C1—C2	115.7 (7)	H5B—C5—H5C	109.5
F2—C1—C2	111.6 (5)

C2—N1—N2—C4	0.0 (3)	F2'—C1—C2—C3	168.0 (11)
C2—N1—N2—C5	−179.4 (3)	F2—C1—C2—C3	143.2 (8)
N2—N1—C2—C3	−0.1 (3)	F1—C1—C2—C3	−98.6 (8)
N2—N1—C2—C1	−175.2 (3)	F3'—C1—C2—C3	42.1 (8)
F1'—C1—C2—N1	108.2 (15)	N1—C2—C3—C4	0.1 (3)
F3—C1—C2—N1	−175.6 (14)	C1—C2—C3—C4	174.7 (3)
F2'—C1—C2—N1	−17.7 (11)	N1—N2—C4—O	178.9 (3)
F2—C1—C2—N1	−42.5 (8)	C5—N2—C4—O	−1.7 (5)
F1—C1—C2—N1	75.7 (8)	N1—N2—C4—C3	0.0 (3)
F3'—C1—C2—N1	−143.6 (7)	C5—N2—C4—C3	179.4 (3)
F1'—C1—C2—C3	−66.1 (16)	C2—C3—C4—O	−178.7 (4)
F3—C1—C2—C3	10.1 (15)	C2—C3—C4—N2	0.0 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O—H0A···N1ⁱ	0.85	1.85	2.698 (3)	176
C5—H5B···F3′ⁱⁱ	0.96	2.55	3.185 (12)	124

Symmetry codes: (i) x, −y+1/2, z+1/2; (ii) −x+1, −y+1, −z.

Experimental details

Crystal data
Chemical formula	C₅H₅F₃N₂O
M_r	166.11
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	7.5500 (15), 8.3530 (17), 11.371 (2)
β (°)	104.72 (3)
V (Å³)	693.6 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.17
Crystal size (mm)	0.20 × 0.10 × 0.10

Data collection
Diffractometer	Enraf–Nonius CAD-4 diffractometer
Absorption correction	ψ scan (North et al., 1968)
T_min, T_max	0.968, 0.984
No. of measured, independent and observed [I > 2σ(I)] reflections	1357, 1259, 856
R_int	0.041
(sin θ/λ)_max (Å⁻¹)	0.602

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.050, 0.168, 1.00
No. of reflections	1259
No. of parameters	130
No. of restraints	36
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.20, −0.21

Computer programs: CAD-4 EXPRESS (Enraf–Nonius, 1994), XCAD4 (Harms & Wocadlo, 1995), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O—H0A···N1ⁱ	0.85	1.85	2.698 (3)	176
C5—H5B···F3'ⁱⁱ	0.96	2.55	3.185 (12)	124

Symmetry codes: (i) x, −y+1/2, z+1/2; (ii) −x+1, −y+1, −z.

References

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. CrossRef Web of Science Google Scholar
Enraf–Nonius (1994). or (1989). CAD-4 Software. Version 5.0. Enraf–Nonius, Delft, The Netherlands. Google Scholar
Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565. CrossRef IUCr Journals Google Scholar
Harms, K. & Wocadlo, S. (1995). XCAD4. University of Marburg, Germany. Google Scholar
Marcos, A. P. & Martins, X. X. (2003). J. Fluorine Chem. 123, 261–265. Google Scholar
North, A. C. T., Phillips, D. C. & Mathews, F. S. (1968). Acta Cryst. A24, 351–359. CrossRef IUCr Journals Web of Science Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Spek, A. L. (2009). Acta Cryst. D65, 148–155. Web of Science CrossRef CAS IUCr Journals Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 65| Part 10| October 2009| Page o2377

doi:10.1107/S1600536809035624

Open

access