5-Hy­droxy-3-phenyl-5-trifluoro­meth­yl-4,5-dihydro-1H-pyrazole

Abstract

The five-membered dihydro­pyrazole ring in the title compound, C₁₀H₉F₃N₂O, is approximately planar (r.m.s. deviation 0.111 Å for all non-H atoms) and its phenyl substituent is aligned at an angle of 14.7 (2)°. Adjacent mol­ecules are linked by N—H⋯O and O—H⋯N hydrogen bonds, generating ribbons running along the b axis of the monoclinic unit cell.

Related literature

For the synthesis, see: Yakimovich et al. (2002 ▶); Zelenin et al. (1995 ▶). For two related structures, see: Dias & Goh (2004 ▶); Yang & Raptis (2003 ▶).

Experimental

Crystal data

• C₁₀H₉F₃N₂O

• M _r = 230.19

• Monoclinic,

• a = 9.1000 (6) Å

• b = 5.4032 (3) Å

• c = 10.4515 (7) Å

• β = 108.139 (7)°

• V = 488.35 (5) ų

• Z = 2

• Mo Kα radiation

• μ = 0.14 mm⁻¹

• T = 100 K

• 0.20 × 0.15 × 0.10 mm

Data collection

• Agilent SuperNova Dual diffractometer with Atlas detector

• Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2010 ▶) T _min = 0.972, T _max = 0.986

• 4222 measured reflections

• 1230 independent reflections

• 1060 reflections with I > 2σ(I)

• R _int = 0.039

Refinement

• R[F ² > 2σ(F ²)] = 0.037

• wR(F ²) = 0.087

• S = 1.05

• 1230 reflections

• 153 parameters

• 3 restraints

• H atoms treated by a mixture of independent and constrained refinement

• Δρ_max = 0.29 e Å⁻³

• Δρ_min = −0.26 e Å⁻³

Data collection: CrysAlis PRO (Agilent, 2010 ▶); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: X-SEED (Barbour, 2001 ▶); software used to prepare material for publication: publCIF (Westrip, 2010 ▶).

Supplementary Material

Supplementary material file. DOI: 10.1107/S160053681103368X/bt5617Isup3.cml

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

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯N1i	0.84 (1)	2.03 (2)	2.833 (3)	162 (4)
N2—H2⋯O1ii	0.88 (1)	2.13 (2)	2.974 (3)	161 (3)

Symmetry codes: (i) ; (ii) .

supplementary crystallographic information

Comment

We had intended to synthesize 5-phenyl-3-(trifluoromethyl)pyrazole, whose crystal structure has been reported (Dias & Goh, 2004). However, the strongly electron-withdrawing nature of the α,β-diketone used in the synthesis led to the isolation of a stable intermediate, a dihydropyrazole (Scheme I), that when dehydrated, should furnish the pyrazole. The synthesis of the dihydropyrazole has previously been reported (Yakimovich et al., 2002; Zelenin et al., 1995). The five-membered dihydropyrazole ring of C₁₀H₉F₃N₂O is approximately planar, the ring being buckled at the methylene carbon, and its phenyl substituent is aligned at 14.7 (2)° (Fig. 1). Adjacent molecules are linked by N—H···O and O—H···N hydrogen bonds (Table 1) to generate a helical chain running along the b axis of the monoclinic unit cell (Fig. 2).

The crystal structure of the 2-naphthyl substituted analog has been reported (Yang & Raptis, 2003); both compounds should similar hydrogen-bonding features.

Experimental

4,4,4-Trifluoro-1-phenyl-1,3-butanedione (10 mmol) in ethanol (50 ml) was refluxed with hydrazine hydrate (10 mmol) for 4 h. Water was added to precipitate the product, which was collected and recrystallized from ethanol; m.p. 415–416 K.

Refinement

Carbon-bound H-atoms were placed in calculated positions [C—H 0.95 Å, U_iso(H) 1.2U_eq(C)] and were included in the refinement in the riding model approximation.

The amino and hydroxy H-atoms were located in a difference Fourier map, and were refined isotropically with distance restraints of N—H 0.88 (1) Å and O—H 0.84 (1) Å.

In the absence of anomalous scatterers, 727 Friedel pairs were merged.

Figures

Fig. 1.

Anisotropic displacement ellipsoid plot (Barbour, 2001) of C10H9F3N2O at the 70% probability level; H atoms are drawn as spheres of arbitrary radius.

Fig. 2.

Hydrogen-bonded ribbon structure.

Crystal data

C10H9F3N2O	F(000) = 236
Mr = 230.19	Dx = 1.565 Mg m−3
Monoclinic, P21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2yb	Cell parameters from 1825 reflections
a = 9.1000 (6) Å	θ = 2.4–29.2°
b = 5.4032 (3) Å	µ = 0.14 mm−1
c = 10.4515 (7) Å	T = 100 K
β = 108.139 (7)°	Prism, colourless
V = 488.35 (5) Å3	0.20 × 0.15 × 0.10 mm
Z = 2

Data collection

Agilent SuperNova Dual diffractometer with Atlas detector	1230 independent reflections
Radiation source: SuperNova (Mo) X-ray Source	1060 reflections with I > 2σ(I)
Mirror	Rint = 0.039
Detector resolution: 10.4041 pixels mm-1	θmax = 27.5°, θmin = 2.4°
ω scans	h = −11→11
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2010)	k = −6→6
Tmin = 0.972, Tmax = 0.986	l = −13→13
4222 measured reflections

Refinement

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)] = 0.037	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.087	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	w = 1/[σ2(Fo2) + (0.0412P)2 + 0.1359P] where P = (Fo2 + 2Fc2)/3
1230 reflections	(Δ/σ)max = 0.001
153 parameters	Δρmax = 0.29 e Å−3
3 restraints	Δρmin = −0.26 e Å−3

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
F1	0.15155 (18)	0.5006 (3)	0.41240 (17)	0.0224 (4)
F2	0.07047 (18)	0.8747 (4)	0.36876 (17)	0.0275 (4)
F3	0.27744 (19)	0.7556 (3)	0.32684 (15)	0.0239 (4)
O1	0.4291 (2)	0.6574 (4)	0.59470 (19)	0.0147 (4)
H1	0.407 (4)	0.534 (5)	0.634 (4)	0.045 (12)*
N1	0.3514 (3)	1.1846 (4)	0.6715 (2)	0.0148 (5)
N2	0.3409 (3)	1.0670 (4)	0.5493 (2)	0.0147 (5)
H2	0.425 (2)	1.094 (6)	0.526 (3)	0.026 (9)*
C1	0.2622 (3)	1.1255 (5)	0.8657 (3)	0.0147 (6)
C2	0.1637 (3)	0.9892 (6)	0.9190 (3)	0.0177 (6)
H2A	0.1048	0.8565	0.8688	0.021*
C3	0.1519 (3)	1.0472 (6)	1.0446 (3)	0.0209 (6)
H3	0.0860	0.9528	1.0807	0.025*
C4	0.2358 (3)	1.2421 (6)	1.1175 (3)	0.0226 (7)
H4	0.2278	1.2809	1.2037	0.027*
C5	0.3317 (3)	1.3813 (6)	1.0650 (3)	0.0212 (6)
H5	0.3879	1.5167	1.1148	0.025*
C6	0.3455 (3)	1.3230 (5)	0.9398 (3)	0.0188 (6)
H6	0.4119	1.4179	0.9045	0.023*
C7	0.2782 (3)	1.0531 (5)	0.7351 (3)	0.0144 (6)
C8	0.2110 (3)	0.8206 (5)	0.6601 (3)	0.0141 (6)
H8A	0.0979	0.8347	0.6169	0.017*
H8B	0.2338	0.6738	0.7197	0.017*
C9	0.2974 (3)	0.8121 (5)	0.5561 (3)	0.0140 (6)
C10	0.1981 (3)	0.7364 (5)	0.4152 (3)	0.0167 (6)

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
F1	0.0249 (9)	0.0185 (9)	0.0224 (8)	−0.0067 (7)	0.0054 (7)	−0.0054 (7)
F2	0.0243 (9)	0.0285 (10)	0.0233 (9)	0.0091 (8)	−0.0019 (7)	0.0000 (8)
F3	0.0318 (9)	0.0273 (10)	0.0154 (8)	−0.0024 (8)	0.0116 (7)	−0.0015 (7)
O1	0.0157 (9)	0.0121 (10)	0.0179 (10)	0.0015 (8)	0.0073 (8)	0.0027 (8)
N1	0.0202 (12)	0.0116 (11)	0.0136 (11)	0.0025 (9)	0.0068 (9)	0.0018 (9)
N2	0.0204 (12)	0.0094 (11)	0.0181 (11)	−0.0013 (10)	0.0116 (9)	−0.0008 (9)
C1	0.0162 (12)	0.0127 (14)	0.0148 (13)	0.0027 (11)	0.0045 (10)	0.0019 (11)
C2	0.0196 (13)	0.0168 (14)	0.0181 (13)	0.0000 (12)	0.0079 (11)	−0.0017 (11)
C3	0.0241 (14)	0.0242 (17)	0.0173 (14)	0.0020 (13)	0.0107 (12)	0.0030 (13)
C4	0.0278 (15)	0.0247 (17)	0.0151 (13)	0.0054 (14)	0.0065 (11)	−0.0013 (13)
C5	0.0220 (14)	0.0196 (15)	0.0212 (15)	0.0026 (13)	0.0054 (12)	−0.0042 (12)
C6	0.0190 (13)	0.0170 (15)	0.0202 (14)	0.0016 (12)	0.0059 (11)	0.0000 (12)
C7	0.0138 (12)	0.0120 (13)	0.0173 (13)	0.0011 (11)	0.0048 (10)	−0.0003 (11)
C8	0.0163 (12)	0.0129 (15)	0.0156 (13)	−0.0001 (11)	0.0086 (10)	0.0000 (11)
C9	0.0145 (12)	0.0130 (15)	0.0155 (13)	0.0013 (11)	0.0061 (10)	0.0002 (11)
C10	0.0209 (14)	0.0141 (15)	0.0154 (13)	0.0002 (12)	0.0061 (10)	0.0007 (12)

Geometric parameters (Å, °)

F1—C10	1.340 (3)	C2—H2A	0.9500
F2—C10	1.338 (3)	C3—C4	1.382 (4)
F3—C10	1.342 (3)	C3—H3	0.9500
O1—C9	1.413 (3)	C4—C5	1.387 (4)
O1—H1	0.836 (10)	C4—H4	0.9500
N1—C7	1.290 (3)	C5—C6	1.389 (4)
N1—N2	1.403 (3)	C5—H5	0.9500
N2—C9	1.441 (4)	C6—H6	0.9500
N2—H2	0.882 (10)	C7—C8	1.505 (4)
C1—C6	1.396 (4)	C8—C9	1.528 (4)
C1—C2	1.403 (4)	C8—H8A	0.9900
C1—C7	1.471 (4)	C8—H8B	0.9900
C2—C3	1.386 (4)	C9—C10	1.524 (4)
C9—O1—H1	107 (3)	C1—C6—H6	119.9
C7—N1—N2	108.6 (2)	N1—C7—C1	123.2 (3)
N1—N2—C9	109.3 (2)	N1—C7—C8	112.5 (2)
N1—N2—H2	111 (2)	C1—C7—C8	124.3 (2)
C9—N2—H2	116 (2)	C7—C8—C9	100.4 (2)
C6—C1—C2	119.0 (3)	C7—C8—H8A	111.7
C6—C1—C7	121.7 (3)	C9—C8—H8A	111.7
C2—C1—C7	119.3 (3)	C7—C8—H8B	111.7
C3—C2—C1	120.4 (3)	C9—C8—H8B	111.7
C3—C2—H2A	119.8	H8A—C8—H8B	109.5
C1—C2—H2A	119.8	O1—C9—N2	111.0 (2)
C4—C3—C2	120.1 (3)	O1—C9—C10	108.2 (2)
C4—C3—H3	120.0	N2—C9—C10	107.4 (2)
C2—C3—H3	120.0	O1—C9—C8	113.2 (2)
C3—C4—C5	120.2 (3)	N2—C9—C8	102.5 (2)
C3—C4—H4	119.9	C10—C9—C8	114.4 (2)
C5—C4—H4	119.9	F2—C10—F1	106.9 (2)
C4—C5—C6	120.1 (3)	F2—C10—F3	107.4 (2)
C4—C5—H5	119.9	F1—C10—F3	107.0 (2)
C6—C5—H5	119.9	F2—C10—C9	112.8 (2)
C5—C6—C1	120.2 (3)	F1—C10—C9	111.4 (2)
C5—C6—H6	119.9	F3—C10—C9	111.1 (2)
C7—N1—N2—C9	−18.0 (3)	C1—C7—C8—C9	−166.2 (2)
C6—C1—C2—C3	−1.3 (4)	N1—N2—C9—O1	−95.1 (2)
C7—C1—C2—C3	177.2 (2)	N1—N2—C9—C10	146.8 (2)
C1—C2—C3—C4	0.8 (4)	N1—N2—C9—C8	25.9 (3)
C2—C3—C4—C5	0.3 (4)	C7—C8—C9—O1	96.5 (2)
C3—C4—C5—C6	−1.0 (4)	C7—C8—C9—N2	−23.0 (2)
C4—C5—C6—C1	0.5 (4)	C7—C8—C9—C10	−138.9 (2)
C2—C1—C6—C5	0.6 (4)	O1—C9—C10—F2	−179.4 (2)
C7—C1—C6—C5	−177.8 (2)	N2—C9—C10—F2	−59.5 (3)
N2—N1—C7—C1	−178.3 (2)	C8—C9—C10—F2	53.5 (3)
N2—N1—C7—C8	1.3 (3)	O1—C9—C10—F1	60.5 (3)
C6—C1—C7—N1	−10.1 (4)	N2—C9—C10—F1	−179.7 (2)
C2—C1—C7—N1	171.5 (2)	C8—C9—C10—F1	−66.7 (3)
C6—C1—C7—C8	170.4 (2)	O1—C9—C10—F3	−58.7 (3)
C2—C1—C7—C8	−8.0 (4)	N2—C9—C10—F3	61.1 (3)
N1—C7—C8—C9	14.3 (3)	C8—C9—C10—F3	174.1 (2)

Hydrogen-bond geometry (Å, °)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1i	0.84 (1)	2.03 (2)	2.833 (3)	162 (4)
N2—H2···O1ii	0.88 (1)	2.13 (2)	2.974 (3)	161 (3)

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