4,6-Bis[5-methyl-3-(trifluoro­meth­yl)pyrazol-1-yl]pyrimidine

Abstract

The complete mol­ecule of the the title compound, C₁₄H₁₀F₆N₆, is generated by crystallographic twofold symmetry, with two C atoms lying on the roatation axis. The dihedral angle between the central and peripheral rings is 25.97 (8)°.

Related literature

For background to fluorine-containing heterocycles and their properties, see: Krishnaiah & Narsaiah (2002 ▶); Ohno et al. (2004 ▶).

Experimental

Crystal data

• C₁₄H₁₀F₆N₆

• M _r = 376.28

• Monoclinic,

• a = 8.5387 (14) Å

• b = 16.110 (6) Å

• c = 11.022 (5) Å

• β = 99.295 (5)°

• V = 1496.2 (9) ų

• Z = 4

• Mo Kα radiation

• μ = 0.16 mm⁻¹

• T = 173 K

• 0.41 × 0.36 × 0.26 mm

Data collection

• Rigaku Saturn724+ CCD diffractometer

• Absorption correction: multi-scan (CrystalClear; Rigaku, 2008 ▶) T _min = 0.938, T _max = 0.960

• 8915 measured reflections

• 1706 independent reflections

• 1678 reflections with I > 2σ(I)

• R _int = 0.033

Refinement

• R[F ² > 2σ(F ²)] = 0.047

• wR(F ²) = 0.100

• S = 1.19

• 1706 reflections

• 120 parameters

• H-atom parameters constrained

• Δρ_max = 0.23 e Å⁻³

• Δρ_min = −0.22 e Å⁻³

Data collection: CrystalClear (Rigaku, 2008 ▶); cell refinement: CrystalClear; data reduction: CrystalClear; 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: SHELXL97.

Supplementary Material

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

supplementary crystallographic information

Comment

Strategically positioned fluorine in heterocyclic compounds, especially those containing trifluromethyl groups plays an important role in medicines and agrochemicals (e.g. Krishnaiah & Narsaiah, 2002). Specifically, the fluorinated pyrazoles have been shown to possess high biological activities (e.g. Ohno et al. 2004) as herbicides, fungicides, insecticides, analgesics, antipyretics and antiinflammatories. Pyrazolopyrimidine and related fuesd heterocycles are of interest as potential bioactive molecules. Recently, the new title compound (I) was synthesized in our group with high herbicidal activity. The crystal structure of the compound (I) is shown in Fig. 1.

Experimental

The title compound (0.1 g) was dissolved in anhydrous methanol (20 ml) at room temperature. Colourless blocks of (I) were obtained through slow evaporation after two weeks.

Refinement

All the hydrogen atoms were placed in idealised positions with C—H = 0.93–0.98Å and U_iso (H) = 1.2–1.5U_ep (C).

Figures

Fig. 1.

The molecular structure of the title compound showing 50% probability displacement ellipsoids and atom-numbering scheme.

Crystal data

C14H10F6N6	F(000) = 760
Mr = 376.28	Dx = 1.670 Mg m−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 648 reflections
a = 8.5387 (14) Å	θ = 2.2–27.5°
b = 16.110 (6) Å	µ = 0.16 mm−1
c = 11.022 (5) Å	T = 173 K
β = 99.295 (5)°	Block, colorless
V = 1496.2 (9) Å3	0.41 × 0.36 × 0.26 mm
Z = 4

Data collection

Rigaku Saturn724+ CCD diffractometer	1706 independent reflections
Radiation source: sealed tube	1678 reflections with I > 2σ(I)
graphite	Rint = 0.033
ω scans at fixed χ = 45°	θmax = 27.5°, θmin = 2.7°
Absorption correction: multi-scan (CrystalClear; Rigaku, 2008)	h = −11→11
Tmin = 0.938, Tmax = 0.960	k = −20→20
8915 measured reflections	l = −14→14

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)] = 0.047	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.100	H-atom parameters constrained
S = 1.19	w = 1/[σ2(Fo2) + (0.0291P)2 + 1.4916P] where P = (Fo2 + 2Fc2)/3
1706 reflections	(Δ/σ)max < 0.001
120 parameters	Δρmax = 0.23 e Å−3
0 restraints	Δρmin = −0.22 e Å−3

Special details

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

	x	y	z	Uiso*/Ueq
F1	0.53252 (12)	0.61885 (7)	0.61601 (11)	0.0484 (3)
F2	0.39212 (17)	0.66320 (8)	0.45033 (11)	0.0610 (4)
F3	0.31154 (14)	0.67824 (7)	0.62363 (12)	0.0544 (3)
N1	0.22004 (15)	0.52452 (8)	0.43231 (12)	0.0284 (3)
N2	0.16127 (15)	0.44751 (8)	0.45125 (11)	0.0269 (3)
N3	0.07685 (16)	0.32384 (8)	0.35077 (13)	0.0311 (3)
C1	0.30268 (18)	0.54413 (10)	0.54059 (14)	0.0288 (3)
C2	0.29725 (19)	0.48203 (10)	0.62924 (14)	0.0310 (4)
H2A	0.3470	0.4829	0.7128	0.037*
C3	0.20539 (18)	0.42006 (10)	0.57018 (14)	0.0289 (3)
C4	0.1508 (2)	0.34123 (11)	0.62036 (16)	0.0369 (4)
H4A	0.1750	0.3423	0.7103	0.055*
H4B	0.2054	0.2942	0.5892	0.055*
H4C	0.0360	0.3353	0.5945	0.055*
C5	0.07580 (17)	0.40647 (10)	0.34787 (13)	0.0266 (3)
C6	0.0000	0.45258 (14)	0.2500	0.0265 (4)
H6A	0.0000	0.5115	0.2500	0.032*
C7	0.0000	0.28736 (15)	0.2500	0.0331 (5)
H7A	0.0000	0.2284	0.2500	0.040*
C8	0.3840 (2)	0.62608 (11)	0.55639 (15)	0.0342 (4)

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
F1	0.0298 (5)	0.0524 (7)	0.0594 (7)	−0.0036 (5)	−0.0038 (5)	−0.0096 (5)
F2	0.0863 (10)	0.0544 (7)	0.0384 (6)	−0.0291 (7)	−0.0011 (6)	0.0066 (5)
F3	0.0461 (7)	0.0431 (6)	0.0754 (9)	0.0017 (5)	0.0146 (6)	−0.0206 (6)
N1	0.0275 (6)	0.0310 (7)	0.0259 (6)	−0.0002 (5)	0.0011 (5)	−0.0002 (5)
N2	0.0254 (6)	0.0302 (7)	0.0242 (6)	0.0013 (5)	0.0014 (5)	0.0006 (5)
N3	0.0300 (7)	0.0313 (7)	0.0311 (7)	0.0019 (5)	0.0023 (5)	0.0010 (6)
C1	0.0251 (7)	0.0353 (8)	0.0256 (7)	0.0034 (6)	0.0027 (6)	−0.0028 (6)
C2	0.0288 (8)	0.0393 (9)	0.0239 (7)	0.0063 (6)	0.0013 (6)	−0.0011 (6)
C3	0.0270 (7)	0.0350 (8)	0.0244 (7)	0.0070 (6)	0.0038 (6)	0.0024 (6)
C4	0.0432 (10)	0.0373 (9)	0.0296 (8)	0.0035 (7)	0.0044 (7)	0.0062 (7)
C5	0.0223 (7)	0.0324 (8)	0.0252 (7)	0.0012 (6)	0.0043 (6)	−0.0016 (6)
C6	0.0236 (10)	0.0292 (11)	0.0262 (10)	0.000	0.0028 (8)	0.000
C7	0.0341 (12)	0.0291 (11)	0.0352 (12)	0.000	0.0032 (9)	0.000
C8	0.0318 (8)	0.0394 (9)	0.0304 (8)	0.0008 (7)	0.0014 (6)	−0.0031 (7)

Geometric parameters (Å, °)

F1—C8	1.3359 (19)	C2—C3	1.368 (2)
F2—C8	1.325 (2)	C2—H2A	0.9500
F3—C8	1.336 (2)	C3—C4	1.490 (2)
N1—C1	1.323 (2)	C4—H4A	0.9800
N1—N2	1.3668 (19)	C4—H4B	0.9800
N2—C3	1.377 (2)	C4—H4C	0.9800
N2—C5	1.414 (2)	C5—C6	1.3815 (19)
N3—C5	1.331 (2)	C6—C5i	1.3815 (19)
N3—C7	1.3319 (17)	C6—H6A	0.9500
C1—C2	1.404 (2)	C7—N3i	1.3319 (17)
C1—C8	1.489 (2)	C7—H7A	0.9500
C1—N1—N2	103.56 (13)	H4A—C4—H4C	109.5
N1—N2—C3	112.71 (12)	H4B—C4—H4C	109.5
N1—N2—C5	117.12 (12)	N3—C5—C6	123.83 (15)
C3—N2—C5	130.02 (14)	N3—C5—N2	116.59 (13)
C5—N3—C7	114.87 (15)	C6—C5—N2	119.57 (15)
N1—C1—C2	112.63 (15)	C5i—C6—C5	114.9 (2)
N1—C1—C8	119.21 (14)	C5i—C6—H6A	122.5
C2—C1—C8	128.13 (15)	C5—C6—H6A	122.5
C3—C2—C1	105.64 (14)	N3—C7—N3i	127.6 (2)
C3—C2—H2A	127.2	N3—C7—H7A	116.2
C1—C2—H2A	127.2	N3i—C7—H7A	116.2
C2—C3—N2	105.44 (14)	F2—C8—F1	107.01 (15)
C2—C3—C4	129.45 (15)	F2—C8—F3	107.49 (16)
N2—C3—C4	124.98 (15)	F1—C8—F3	105.65 (14)
C3—C4—H4A	109.5	F2—C8—C1	112.77 (14)
C3—C4—H4B	109.5	F1—C8—C1	111.59 (14)
H4A—C4—H4B	109.5	F3—C8—C1	111.93 (14)
C3—C4—H4C	109.5
C1—N1—N2—C3	0.68 (16)	N1—N2—C5—N3	152.46 (14)
C1—N1—N2—C5	−175.36 (13)	C3—N2—C5—N3	−22.8 (2)
N2—N1—C1—C2	−0.63 (17)	N1—N2—C5—C6	−26.16 (18)
N2—N1—C1—C8	−179.10 (13)	C3—N2—C5—C6	158.62 (13)
N1—C1—C2—C3	0.37 (18)	N3—C5—C6—C5i	−0.48 (11)
C8—C1—C2—C3	178.67 (15)	N2—C5—C6—C5i	178.03 (15)
C1—C2—C3—N2	0.07 (17)	C5—N3—C7—N3i	−0.43 (10)
C1—C2—C3—C4	−175.86 (16)	N1—C1—C8—F2	−14.0 (2)
N1—N2—C3—C2	−0.47 (17)	C2—C1—C8—F2	167.76 (16)
C5—N2—C3—C2	174.92 (14)	N1—C1—C8—F1	−134.52 (15)
N1—N2—C3—C4	175.69 (14)	C2—C1—C8—F1	47.3 (2)
C5—N2—C3—C4	−8.9 (3)	N1—C1—C8—F3	107.31 (17)
C7—N3—C5—C6	0.9 (2)	C2—C1—C8—F3	−70.9 (2)
C7—N3—C5—N2	−177.66 (11)

Symmetry codes: (i) −x, y, −z+1/2.