4-(4-Chloro-5-methyl-3-trifluoro­meth­yl-1H-pyrazol-1-yl)-6-(prop-2-ynyl­oxy)pyrimidine

Xie, R.-L.; Zhang, T.; Cao, A.-C.; Mei, X.-D.

doi:10.1107/S1600536810031740

organic compounds

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ISSN: 2056-9890

Volume 66| Part 9| September 2010| Page o2307

https://doi.org/10.1107/S1600536810031740

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4-(4-Chloro-5-methyl-3-trifluoromethyl-1H-pyrazol-1-yl)-6-(prop-2-ynyloxy)pyrimidine

Ru-Liang Xie,^a Tao Zhang,^a Ao-Cheng Cao ^a and Xiang-Dong Mei ^a ^*

^aState Key Laboratory for the Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, People's Republic of China
^*Correspondence e-mail: meixiangdong@gmail.com

(Received 6 January 2010; accepted 7 August 2010; online 18 August 2010)

The molecule of the title compound, C₁₂H₈ClF₃N₄O, is twisted as indicated by the C—O—C—C torsion angle of 76.9 (3)°. Moreover, the trifluoromethyl group shows rotational disorder of the F atoms, with site-occupancy factors of 0.653 (6) and 0.347 (6). The dihedral angle between the rings is 1.88 (12) Å.

Related literature

For the applications of pyrazole derivatives, see: Hirai et al. (2002 ); Krishnaiah et al. (2002 ); Ohno et al. (2004 ); Li et al. (2008 ); Shiga et al. (2003 ); Vicentini et al. (2007 ).

Experimental

Crystal data

C₁₂H₈ClF₃N₄O
M_r = 316.67
Monoclinic, P 2₁ /n
a = 7.8331 (13) Å
b = 7.7258 (12) Å
c = 21.757 (4) Å
β = 99.270 (11)°
V = 1299.5 (4) Å³
Z = 4
Cu Kα radiation
μ = 3.02 mm⁻¹
T = 173 K
0.20 × 0.20 × 0.10 mm

Data collection

Rigaku R-AXIS RAPID IP area-detector diffractometer
Absorption correction: multi-scan (ABSCOR; Higashi, 1995 ) T_min = 0.583, T_max = 0.752
8543 measured reflections
2361 independent reflections
2009 reflections with I > 2σ(I)
R_int = 0.043

Refinement

R[F² > 2σ(F²)] = 0.044
wR(F²) = 0.106
S = 1.07
2361 reflections
220 parameters
69 restraints
H-atom parameters constrained
Δρ_max = 0.31 e Å⁻³
Δρ_min = −0.22 e Å⁻³

Data collection: RAPID-AUTO (Rigaku, 2001 ); cell refinement: RAPID-AUTO; data reduction: RAPID-AUTO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP (Siemens, 1998 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536810031740/rn2068sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810031740/rn2068Isup2.hkl

checkCIF report

Comment top

There is much agrochemical interest in pyrazole derivatives because of their excellent bioactivity (Krishnaiah et al., 2002; Ohno et al., 2004; Li et al., 2008 Shiga et al., 2003; Vicentini et al., 2007). Numerous herbicides such as pyrazolate, pyrazoxyfen, benzofenap, pyraflufen-ethyl, fluazolate and pyrazosulfuron-ethyl with pyrazole moieties were commercialized (Hirai et al., 2002). Recently, a novel pyrazole derivative (I) with a trifluoromethyl group was synthesized. The trifluoromethyl group shows rotational disorder of the F atoms, with site occupancy factors of 0.653 (6) and 0.347 (6). This molecule is twisted, prop-2-ynyloxy is out of the pyrimidine ring plane, as indicated by the C(8)—O(1)—C(10)—C(11) torsion angle of 76.9 (3)°. The crystal structure of the title compound is shown in Fig. 1.

Related literature top

For the applications of pyrazole derivatives, see: Hirai et al. (2002); Krishnaiah et al. (2002); Ohno et al. (2004); Li et al. (2008); Shiga et al. (2003); Vicentini et al. (2007).

Experimental top

The title compound (0.15 g) was dissolved in the mixed solvent of ethanol and acetone (25 mL) at room temperature. Colorless single crystals of compound (I) were obtained through slow evaporation after two weeks.

Structure description top

For the applications of pyrazole derivatives, see: Hirai et al. (2002); Krishnaiah et al. (2002); Ohno et al. (2004); Li et al. (2008); Shiga et al. (2003); Vicentini et al. (2007).

Computing details top

Data collection: RAPID-AUTO (Rigaku, 2001); cell refinement: RAPID-AUTO (Rigaku, 2001); data reduction: RAPID-AUTO (Rigaku, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP (Siemens, 1998); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

Fig. 1. The structure of the title compound with labeling scheme; displacement ellipsoids are shown at the 30% probability level and atoms F1', F2' and F3' representing the smaller fraction of the disordered trifluoromethyl group have been excluded.

4-(4-Chloro-5-methyl-3-trifluoromethyl-1H-pyrazol-1-yl)-6-(prop-2- ynyloxy)pyrimidine top

Crystal data top

C₁₂H₈ClF₃N₄O	F(000) = 640
M_r = 316.67	D_x = 1.619 Mg m⁻³
Monoclinic, P2₁/n	Cu Kα radiation, λ = 1.54186 Å
a = 7.8331 (13) Å	Cell parameters from 564 reflections
b = 7.7258 (12) Å	θ = 2.2–68.3°
c = 21.757 (4) Å	µ = 3.02 mm⁻¹
β = 99.270 (11)°	T = 173 K
V = 1299.5 (4) Å³	Platelet, colorless
Z = 4	0.20 × 0.20 × 0.10 mm

Data collection top

Rigaku R-AXIS RAPID IP area-detector diffractometer	2361 independent reflections
Radiation source: rotating anode	2009 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.043
ω scans at fixed χ = 45°	θ_max = 68.3°, θ_min = 4.1°
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	h = −9→9
T_min = 0.583, T_max = 0.752	k = −9→6
8543 measured reflections	l = −26→22

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)] = 0.044	H-atom parameters constrained
wR(F²) = 0.106	w = 1/[σ²(F_o²) + (0.0399P)² + 0.8523P] where P = (F_o² + 2F_c²)/3
S = 1.07	(Δ/σ)_max = 0.016
2361 reflections	Δρ_max = 0.31 e Å⁻³
220 parameters	Δρ_min = −0.22 e Å⁻³
69 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: 0.0054 (5)

Crystal data top

C₁₂H₈ClF₃N₄O	V = 1299.5 (4) Å³
M_r = 316.67	Z = 4
Monoclinic, P2₁/n	Cu Kα radiation
a = 7.8331 (13) Å	µ = 3.02 mm⁻¹
b = 7.7258 (12) Å	T = 173 K
c = 21.757 (4) Å	0.20 × 0.20 × 0.10 mm
β = 99.270 (11)°

Data collection top

Rigaku R-AXIS RAPID IP area-detector diffractometer	2361 independent reflections
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	2009 reflections with I > 2σ(I)
T_min = 0.583, T_max = 0.752	R_int = 0.043
8543 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.044	69 restraints
wR(F²) = 0.106	H-atom parameters constrained
S = 1.07	Δρ_max = 0.31 e Å⁻³
2361 reflections	Δρ_min = −0.22 e Å⁻³
220 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 > 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) top

	x	y	z	U_iso*/U_eq	Occ. (<1)
Cl1	0.05485 (8)	0.66461 (9)	0.12912 (3)	0.0419 (2)
F1	0.0581 (14)	1.0026 (19)	0.2067 (6)	0.068 (3)	0.65 (3)
F2	0.1586 (17)	1.2382 (8)	0.1787 (5)	0.066 (2)	0.65 (3)
F3	0.3301 (10)	1.040 (2)	0.2184 (4)	0.080 (3)	0.65 (3)
F1'	0.038 (2)	1.038 (4)	0.2018 (12)	0.062 (4)	0.35 (3)
F2'	0.229 (4)	1.227 (2)	0.1908 (8)	0.074 (4)	0.35 (3)
F3'	0.298 (3)	0.977 (3)	0.2215 (7)	0.076 (4)	0.35 (3)
O1	0.4744 (2)	1.4528 (2)	−0.08155 (7)	0.0328 (4)
N1	0.2473 (2)	1.0968 (3)	0.07612 (9)	0.0307 (5)
N2	0.2397 (2)	0.9953 (2)	0.02454 (9)	0.0273 (4)
N3	0.2814 (3)	0.9661 (3)	−0.07855 (9)	0.0339 (5)
N4	0.4008 (2)	1.1943 (3)	−0.13275 (9)	0.0300 (5)
C1	0.1864 (3)	0.9977 (3)	0.11729 (11)	0.0298 (5)
C2	0.1401 (3)	0.8333 (3)	0.09272 (11)	0.0292 (5)
C3	0.1757 (3)	0.8320 (3)	0.03301 (11)	0.0280 (5)
C4	0.1845 (3)	1.0661 (4)	0.18093 (13)	0.0407 (6)
C5	0.1542 (3)	0.6869 (3)	−0.01239 (12)	0.0369 (6)
H5A	0.2630	0.6681	−0.0282	0.055*
H5B	0.0626	0.7155	−0.0471	0.055*
H5C	0.1228	0.5814	0.0082	0.055*
C6	0.2966 (3)	1.0682 (3)	−0.02856 (10)	0.0261 (5)
C7	0.3362 (3)	1.0361 (3)	−0.12775 (12)	0.0349 (6)
H7A	0.3284	0.9648	−0.1637	0.042*
C8	0.4111 (3)	1.2901 (3)	−0.08172 (11)	0.0271 (5)
C9	0.3614 (3)	1.2338 (3)	−0.02663 (10)	0.0275 (5)
H9A	0.3714	1.3042	0.0096	0.033*
C10	0.5077 (3)	1.5223 (3)	−0.14053 (11)	0.0350 (6)
H10A	0.5662	1.4332	−0.1624	0.042*
H10B	0.5861	1.6231	−0.1325	0.042*
C11	0.3481 (3)	1.5756 (3)	−0.18034 (11)	0.0355 (6)
C12	0.2244 (4)	1.6239 (4)	−0.21331 (13)	0.0516 (8)
H12	0.1240	1.6632	−0.2401	0.062*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0394 (4)	0.0400 (4)	0.0474 (4)	−0.0066 (3)	0.0100 (3)	0.0144 (3)
F1	0.087 (5)	0.079 (5)	0.049 (3)	−0.028 (4)	0.042 (4)	−0.006 (3)
F2	0.111 (5)	0.046 (2)	0.048 (3)	0.007 (3)	0.035 (3)	−0.0082 (17)
F3	0.055 (2)	0.137 (6)	0.046 (3)	0.014 (3)	−0.0046 (18)	−0.036 (3)
F1'	0.040 (5)	0.092 (9)	0.058 (6)	0.002 (5)	0.021 (4)	−0.015 (6)
F2'	0.128 (9)	0.058 (5)	0.044 (5)	−0.048 (6)	0.034 (6)	−0.014 (4)
F3'	0.089 (7)	0.092 (8)	0.038 (4)	0.028 (5)	−0.015 (4)	0.006 (5)
O1	0.0436 (10)	0.0302 (9)	0.0243 (9)	−0.0109 (8)	0.0043 (7)	0.0016 (7)
N1	0.0350 (11)	0.0304 (11)	0.0280 (11)	−0.0009 (9)	0.0088 (8)	−0.0017 (8)
N2	0.0286 (10)	0.0263 (10)	0.0275 (10)	−0.0011 (8)	0.0057 (8)	0.0002 (8)
N3	0.0423 (12)	0.0294 (11)	0.0307 (11)	−0.0047 (9)	0.0079 (9)	−0.0037 (9)
N4	0.0310 (10)	0.0307 (11)	0.0288 (11)	−0.0015 (9)	0.0064 (8)	−0.0027 (8)
C1	0.0274 (12)	0.0326 (13)	0.0302 (13)	0.0023 (10)	0.0070 (9)	0.0035 (10)
C2	0.0239 (11)	0.0312 (13)	0.0329 (13)	−0.0002 (10)	0.0058 (9)	0.0075 (10)
C3	0.0220 (11)	0.0263 (12)	0.0350 (13)	0.0006 (9)	0.0023 (9)	0.0026 (10)
C4	0.0404 (14)	0.0476 (17)	0.0370 (15)	−0.0060 (13)	0.0149 (12)	0.0012 (12)
C5	0.0393 (13)	0.0305 (13)	0.0405 (15)	−0.0069 (11)	0.0053 (11)	−0.0012 (11)
C6	0.0237 (11)	0.0276 (12)	0.0269 (12)	0.0016 (9)	0.0040 (9)	0.0013 (9)
C7	0.0447 (14)	0.0318 (14)	0.0292 (13)	−0.0044 (11)	0.0095 (11)	−0.0075 (10)
C8	0.0243 (11)	0.0260 (12)	0.0305 (13)	−0.0012 (9)	0.0032 (9)	0.0005 (10)
C9	0.0320 (12)	0.0254 (12)	0.0248 (12)	−0.0024 (10)	0.0035 (9)	−0.0017 (9)
C10	0.0406 (14)	0.0362 (14)	0.0290 (13)	−0.0099 (11)	0.0078 (10)	0.0053 (11)
C11	0.0497 (15)	0.0310 (14)	0.0269 (13)	0.0004 (12)	0.0093 (11)	−0.0015 (10)
C12	0.0613 (19)	0.0503 (18)	0.0402 (16)	0.0150 (15)	−0.0008 (14)	−0.0051 (14)

Geometric parameters (Å, º) top

Cl1—C2	1.715 (2)	C1—C2	1.403 (3)
F1—C4	1.309 (7)	C1—C4	1.484 (4)
F2—C4	1.344 (6)	C2—C3	1.372 (3)
F3—C4	1.306 (7)	C3—C5	1.486 (3)
F1'—C4	1.316 (12)	C5—H5A	0.9800
F2'—C4	1.300 (11)	C5—H5B	0.9800
F3'—C4	1.339 (10)	C5—H5C	0.9800
O1—C8	1.352 (3)	C6—C9	1.374 (3)
O1—C10	1.452 (3)	C7—H7A	0.9500
N1—C1	1.324 (3)	C8—C9	1.389 (3)
N1—N2	1.362 (3)	C9—H9A	0.9500
N2—C3	1.380 (3)	C10—C11	1.461 (3)
N2—C6	1.420 (3)	C10—H10A	0.9900
N3—C7	1.330 (3)	C10—H10B	0.9900
N3—C6	1.333 (3)	C11—C12	1.170 (4)
N4—C8	1.326 (3)	C12—H12	0.9500
N4—C7	1.334 (3)

C8—O1—C10	117.33 (18)	F3—C4—C1	112.9 (4)
C1—N1—N2	104.57 (19)	F1—C4—C1	112.9 (7)
N1—N2—C3	112.62 (19)	F1'—C4—C1	113.8 (12)
N1—N2—C6	117.62 (18)	F3'—C4—C1	109.1 (8)
C3—N2—C6	129.8 (2)	F2—C4—C1	110.0 (4)
C7—N3—C6	114.7 (2)	C3—C5—H5A	109.5
C8—N4—C7	114.6 (2)	C3—C5—H5B	109.5
N1—C1—C2	111.4 (2)	H5A—C5—H5B	109.5
N1—C1—C4	119.0 (2)	C3—C5—H5C	109.5
C2—C1—C4	129.5 (2)	H5A—C5—H5C	109.5
C3—C2—C1	106.7 (2)	H5B—C5—H5C	109.5
C3—C2—Cl1	125.8 (2)	N3—C6—C9	124.0 (2)
C1—C2—Cl1	127.46 (19)	N3—C6—N2	115.5 (2)
C2—C3—N2	104.7 (2)	C9—C6—N2	120.5 (2)
C2—C3—C5	128.1 (2)	N3—C7—N4	127.9 (2)
N2—C3—C5	127.3 (2)	N3—C7—H7A	116.1
F2'—C4—F3	81.9 (8)	N4—C7—H7A	116.1
F2'—C4—F1	119.3 (10)	N4—C8—O1	119.6 (2)
F3—C4—F1	108.6 (7)	N4—C8—C9	124.1 (2)
F2'—C4—F1'	109.0 (14)	O1—C8—C9	116.3 (2)
F3—C4—F1'	118.7 (11)	C6—C9—C8	114.7 (2)
F1—C4—F1'	14.2 (15)	C6—C9—H9A	122.6
F2'—C4—F3'	104.4 (9)	C8—C9—H9A	122.6
F3—C4—F3'	24.2 (8)	O1—C10—C11	111.7 (2)
F1—C4—F3'	89.7 (10)	O1—C10—H10A	109.3
F1'—C4—F3'	102.3 (13)	C11—C10—H10A	109.3
F2'—C4—F2	25.2 (10)	O1—C10—H10B	109.3
F3—C4—F2	106.6 (5)	C11—C10—H10B	109.3
F1—C4—F2	105.4 (7)	H10A—C10—H10B	107.9
F1'—C4—F2	92.4 (11)	C12—C11—C10	177.0 (3)
F3'—C4—F2	127.7 (7)	C11—C12—H12	180.0
F2'—C4—C1	116.8 (7)

C1—N1—N2—C3	−0.5 (2)	C2—C1—C4—F1'	−49.2 (13)
C1—N1—N2—C6	179.62 (18)	N1—C1—C4—F3'	−112.0 (12)
N2—N1—C1—C2	0.1 (2)	C2—C1—C4—F3'	64.2 (13)
N2—N1—C1—C4	177.0 (2)	N1—C1—C4—F2	32.5 (7)
N1—C1—C2—C3	0.3 (3)	C2—C1—C4—F2	−151.3 (7)
C4—C1—C2—C3	−176.2 (2)	C7—N3—C6—C9	0.6 (3)
N1—C1—C2—Cl1	−179.60 (17)	C7—N3—C6—N2	−179.65 (19)
C4—C1—C2—Cl1	3.9 (4)	N1—N2—C6—N3	−177.90 (19)
C1—C2—C3—N2	−0.6 (2)	C3—N2—C6—N3	2.3 (3)
Cl1—C2—C3—N2	179.31 (16)	N1—N2—C6—C9	1.8 (3)
C1—C2—C3—C5	178.3 (2)	C3—N2—C6—C9	−178.0 (2)
Cl1—C2—C3—C5	−1.8 (4)	C6—N3—C7—N4	−1.0 (4)
N1—N2—C3—C2	0.7 (2)	C8—N4—C7—N3	0.4 (4)
C6—N2—C3—C2	−179.5 (2)	C7—N4—C8—O1	−179.9 (2)
N1—N2—C3—C5	−178.1 (2)	C7—N4—C8—C9	0.6 (3)
C6—N2—C3—C5	1.7 (4)	C10—O1—C8—N4	7.7 (3)
N1—C1—C4—F2'	6.0 (16)	C10—O1—C8—C9	−172.72 (19)
C2—C1—C4—F2'	−177.7 (16)	N3—C6—C9—C8	0.2 (3)
N1—C1—C4—F3	−86.4 (9)	N2—C6—C9—C8	−179.49 (19)
C2—C1—C4—F3	89.9 (9)	N4—C8—C9—C6	−0.9 (3)
N1—C1—C4—F1	150.0 (8)	O1—C8—C9—C6	179.58 (19)
C2—C1—C4—F1	−33.8 (8)	C8—O1—C10—C11	76.9 (3)
N1—C1—C4—F1'	134.5 (13)	O1—C10—C11—C12	149 (6)

Experimental details

Crystal data
Chemical formula	C₁₂H₈ClF₃N₄O
M_r	316.67
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	173
a, b, c (Å)	7.8331 (13), 7.7258 (12), 21.757 (4)
β (°)	99.270 (11)
V (Å³)	1299.5 (4)
Z	4
Radiation type	Cu Kα
µ (mm⁻¹)	3.02
Crystal size (mm)	0.20 × 0.20 × 0.10

Data collection
Diffractometer	Rigaku R-AXIS RAPID IP area-detector
Absorption correction	Multi-scan (ABSCOR; Higashi, 1995)
T_min, T_max	0.583, 0.752
No. of measured, independent and observed [I > 2σ(I)] reflections	8543, 2361, 2009
R_int	0.043
(sin θ/λ)_max (Å⁻¹)	0.602

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.044, 0.106, 1.07
No. of reflections	2361
No. of parameters	220
No. of restraints	69
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.31, −0.22

Computer programs: RAPID-AUTO (Rigaku, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XP (Siemens, 1998).

Acknowledgements

This work was supported by the Agricultural Public Sector Research and Special Funds (200803021) and the Major State Basic Reasearch Development Program of China (No. 2006CB101907 and No. 2010CB126106).

References

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