Ethyl 3-bromo-1-(3-chloro­pyridin-2-yl)-1H-pyrazole-5-carboxyl­ate

Abstract

The title compound, C₁₁H₉BrClN₃O₂, is an inter­mediate in the synthesis of Rynaxypyre, a new insecticidal anthranilic diamide used as a potent and selective ryanodine receptor activator. The dihedral angle between the aromatic ring planes is 78.7 (2)°.

Related literature

For the synthetic procedure, see: Lahm et al. (2007 ▶). For bond-length data, see: Allen et al. (1987 ▶).

Experimental

Crystal data

• C₁₁H₉BrClN₃O₂

• M _r = 330.57

• Orthorhombic,

• a = 7.404 (2) Å

• b = 10.024 (2) Å

• c = 17.072 (3) Å

• V = 1267.0 (4) ų

• Z = 4

• Mo Kα radiation

• μ = 3.45 mm⁻¹

• T = 298 (2) K

• 0.40 × 0.30 × 0.30 mm

Data collection

• Enraf–Nonius CAD-4 diffractometer

• Absorption correction: ψ scan (North et al., 1968 ▶) T _min = 0.339, T _max = 0.424 (expected range = 0.284–0.355)

• 2295 measured reflections

• 1347 independent reflections

• 959 reflections with I > 2σ(I)

• R _int = 0.051

• 3 standard reflections every 200 reflections intensity decay: 1%

Refinement

• R[F ² > 2σ(F ²)] = 0.056

• wR(F ²) = 0.129

• S = 1.00

• 1347 reflections

• 163 parameters

• H-atom parameters constrained

• Δρ_max = 0.33 e Å⁻³

• Δρ_min = −0.42 e Å⁻³

• Absolute structure: Flack (1983 ▶), 15 Friedel pairs

• Flack parameter: 0.37

Data collection: CAD-4 Software (Enraf–Nonius, 1985 ▶); cell refinement: CAD-4 Software; 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: SHELXTL.

Supplementary Material

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

supplementary crystallographic information

Comment

Ethyl 3-bromo-1-(3-chloropyridin-2-yl)-1H-pyrazole-5-carboxylate is one of the important intermediates in the synthesis of Rynaxypyre, a new insecticidal anthranilic diamide used as a potent and selective ryanodine receptor activator (Lahm et al., 2007).

The molecular structure of (I) is shown in Fig. 1, a full list of geometric parameters is given in the supplementary material. The bond lengths and angles are within normal ranges (Allen et al., 1987). The dihedral angle of the rings A (C1—C5/N1) and B(C9—C11/N2/N3) is measured to 78.7 (2)°.

No obvious intra- or inter-molecular hydrogen bonds were observed in the crystal structure (Fig. 2).

Experimental

The title compound (I) was synthesized by a method reported in the literature (Lahm et al., 2007). Crystals of the title compound were obtained by dissolving ethyl 3-bromo-1-(3-chloropyridin-2-yl)-1H-pyrazole-5-carboxylate (3.3 g, 10.0 mmol) in acetonitrile (60 ml) and evaporating the solvent slowly at room temperature for about 20 d.

Refinement

H atoms were positioned geometrically, with O—H = 0.82 Å and C—H = 0.93Å for aromatic H, 0.97 Å for CH₂ and 0.96 Å for CH₃ groups. Hydrogen atoms were constrained to ride on their parent atoms, with U_iso(H) = xU_eq(C/O), where x = 1.2 for aromatic H and x = 1.5 for other H.

Figures

Fig. 1.

A drawing of the title molecular structure, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.

Fig. 2.

A packing diagram for (I).

Crystal data

C11H9BrClN3O2	F(000) = 656
Mr = 330.57	Dx = 1.733 Mg m−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 25 reflections
a = 7.404 (2) Å	θ = 9–13°
b = 10.024 (2) Å	µ = 3.45 mm−1
c = 17.072 (3) Å	T = 298 K
V = 1267.0 (4) Å3	Block, colourless
Z = 4	0.40 × 0.30 × 0.30 mm

Data collection

Enraf–Nonius CAD-4 diffractometer	959 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.051
graphite	θmax = 25.3°, θmin = 2.4°
ω/2θ scans	h = 0→8
Absorption correction: ψ scan (North et al., 1968)	k = 0→12
Tmin = 0.339, Tmax = 0.424	l = −20→20
2295 measured reflections	3 standard reflections every 200 reflections
1347 independent reflections	intensity decay: 1%

Refinement

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)] = 0.056	H-atom parameters constrained
wR(F2) = 0.129	w = 1/[σ2(Fo2) + (0.063P)2 + 0.5P] where P = (Fo2 + 2Fc2)/3
S = 1.00	(Δ/σ)max = 0.001
1347 reflections	Δρmax = 0.33 e Å−3
163 parameters	Δρmin = −0.42 e Å−3
0 restraints	Absolute structure: Flack (1983), 155 Frieldel pairs
Primary atom site location: structure-invariant direct methods	Flack parameter: 0.37

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
Br	0.03831 (14)	0.07498 (8)	0.79256 (5)	0.0580 (3)
Cl	0.2975 (3)	0.5607 (2)	0.90139 (15)	0.0661 (6)
O1	0.0029 (10)	0.4767 (5)	1.0803 (3)	0.0645 (19)
N1	−0.2392 (8)	0.5697 (7)	0.9219 (4)	0.0481 (16)
C1	0.0862 (11)	0.6189 (7)	0.9087 (5)	0.046 (2)
C2	0.0441 (15)	0.7564 (7)	0.9030 (4)	0.056 (2)
H2A	0.1355	0.8190	0.8964	0.067*
N2	−0.0180 (10)	0.3292 (5)	0.8505 (3)	0.0457 (17)
O2	0.0190 (8)	0.2604 (4)	1.1121 (3)	0.0483 (14)
N3	−0.0260 (10)	0.3932 (5)	0.9196 (3)	0.0442 (16)
C3	−0.1273 (14)	0.7949 (8)	0.9073 (6)	0.059 (2)
H3A	−0.1564	0.8848	0.9027	0.071*
C4	−0.2629 (11)	0.7014 (8)	0.9187 (5)	0.055 (2)
H4A	−0.3801	0.7333	0.9245	0.066*
C5	−0.0628 (13)	0.5354 (6)	0.9191 (4)	0.045 (2)
C6	0.0235 (18)	0.1666 (8)	1.2393 (5)	0.074 (3)
H6A	0.0324	0.1860	1.2943	0.111*
H6B	0.1218	0.1099	1.2241	0.111*
H6C	−0.0889	0.1224	1.2289	0.111*
C7	0.0317 (13)	0.2919 (7)	1.1945 (4)	0.0476 (19)
H7A	−0.0671	0.3499	1.2097	0.057*
H7B	0.1444	0.3377	1.2052	0.057*
C8	0.0085 (12)	0.3603 (7)	1.0617 (4)	0.046 (2)
C9	0.0042 (11)	0.3108 (6)	0.9816 (4)	0.041 (2)
C10	0.0303 (12)	0.1880 (6)	0.9503 (4)	0.0413 (17)
H10A	0.0526	0.1092	0.9773	0.050*
C11	0.0173 (11)	0.2032 (6)	0.8719 (4)	0.0383 (18)

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Br	0.0822 (6)	0.0377 (4)	0.0539 (4)	0.0033 (5)	0.0035 (5)	−0.0055 (4)
Cl	0.0537 (13)	0.0473 (14)	0.0974 (17)	0.0016 (12)	0.0030 (12)	0.0009 (13)
O1	0.107 (6)	0.032 (3)	0.054 (3)	−0.003 (3)	−0.006 (4)	−0.004 (2)
N1	0.047 (4)	0.028 (4)	0.070 (4)	0.004 (4)	0.019 (3)	0.005 (4)
C1	0.045 (5)	0.034 (4)	0.058 (5)	0.004 (3)	0.002 (4)	0.000 (3)
C2	0.082 (7)	0.026 (4)	0.059 (5)	0.001 (5)	0.018 (6)	0.003 (3)
N2	0.067 (5)	0.028 (3)	0.042 (3)	0.003 (3)	−0.014 (4)	0.002 (2)
O2	0.070 (4)	0.035 (3)	0.040 (2)	0.000 (3)	−0.004 (3)	−0.001 (2)
N3	0.066 (4)	0.024 (3)	0.043 (3)	−0.003 (3)	−0.001 (3)	−0.001 (2)
C3	0.071 (7)	0.030 (5)	0.077 (6)	0.009 (5)	0.004 (6)	−0.003 (4)
C4	0.034 (5)	0.052 (5)	0.079 (6)	0.001 (4)	0.002 (5)	−0.001 (5)
C5	0.073 (6)	0.025 (4)	0.036 (4)	−0.010 (4)	−0.005 (4)	0.007 (3)
C6	0.113 (9)	0.058 (5)	0.050 (5)	0.006 (6)	−0.006 (6)	0.013 (4)
C7	0.059 (5)	0.043 (4)	0.041 (4)	0.010 (4)	−0.006 (4)	−0.005 (3)
C8	0.057 (7)	0.029 (4)	0.052 (4)	−0.008 (4)	0.009 (4)	0.001 (3)
C9	0.052 (6)	0.030 (4)	0.041 (4)	−0.001 (4)	0.000 (4)	0.001 (3)
C10	0.057 (5)	0.019 (3)	0.048 (4)	0.002 (4)	−0.003 (4)	0.003 (3)
C11	0.044 (5)	0.025 (3)	0.046 (4)	−0.004 (3)	0.003 (4)	0.001 (3)

Geometric parameters (Å, °)

Br—C11	1.874 (6)	N3—C5	1.452 (8)
Cl—C1	1.675 (8)	C3—C4	1.387 (12)
O1—C8	1.210 (7)	C3—H3A	0.9300
N1—C4	1.334 (9)	C4—H4A	0.9300
N1—C5	1.351 (11)	C6—C7	1.472 (9)
C1—C5	1.396 (11)	C6—H6A	0.9600
C1—C2	1.416 (10)	C6—H6B	0.9600
C2—C3	1.328 (12)	C6—H6C	0.9600
C2—H2A	0.9300	C7—H7A	0.9700
N2—C11	1.340 (8)	C7—H7B	0.9700
N2—N3	1.344 (7)	C8—C9	1.454 (10)
O2—C8	1.323 (8)	C9—C10	1.356 (9)
O2—C7	1.445 (7)	C10—C11	1.351 (9)
N3—C9	1.361 (8)	C10—H10A	0.9300
C4—N1—C5	112.2 (6)	H6A—C6—H6B	109.5
C5—C1—C2	114.7 (8)	C7—C6—H6C	109.5
C5—C1—Cl	122.6 (6)	H6A—C6—H6C	109.5
C2—C1—Cl	122.6 (7)	H6B—C6—H6C	109.5
C3—C2—C1	119.3 (9)	O2—C7—C6	108.5 (6)
C3—C2—H2A	120.4	O2—C7—H7A	110.0
C1—C2—H2A	120.4	C6—C7—H7A	110.0
C11—N2—N3	102.7 (5)	O2—C7—H7B	110.0
C8—O2—C7	118.2 (5)	C6—C7—H7B	110.0
N2—N3—C9	112.7 (5)	H7A—C7—H7B	108.4
N2—N3—C5	118.2 (5)	O1—C8—O2	124.1 (7)
C9—N3—C5	129.1 (5)	O1—C8—C9	125.1 (7)
C2—C3—C4	120.2 (8)	O2—C8—C9	110.8 (6)
C2—C3—H3A	119.9	C10—C9—N3	105.5 (6)
C4—C3—H3A	119.9	C10—C9—C8	132.6 (6)
N1—C4—C3	125.4 (8)	N3—C9—C8	121.9 (6)
N1—C4—H4A	117.3	C11—C10—C9	106.1 (6)
C3—C4—H4A	117.3	C11—C10—H10A	126.9
N1—C5—C1	128.0 (6)	C9—C10—H10A	126.9
N1—C5—N3	115.5 (7)	N2—C11—C10	113.0 (6)
C1—C5—N3	116.2 (8)	N2—C11—Br	117.8 (5)
C7—C6—H6A	109.5	C10—C11—Br	129.2 (5)
C7—C6—H6B	109.5
C5—C1—C2—C3	−0.4 (12)	C8—O2—C7—C6	174.4 (8)
Cl—C1—C2—C3	178.2 (8)	C7—O2—C8—O1	−2.5 (13)
C11—N2—N3—C9	0.4 (9)	C7—O2—C8—C9	177.6 (7)
C11—N2—N3—C5	180.0 (7)	N2—N3—C9—C10	−0.9 (10)
C1—C2—C3—C4	1.2 (15)	C5—N3—C9—C10	179.6 (8)
C5—N1—C4—C3	4.9 (12)	N2—N3—C9—C8	177.7 (7)
C2—C3—C4—N1	−3.8 (16)	C5—N3—C9—C8	−1.8 (14)
C4—N1—C5—C1	−4.2 (11)	O1—C8—C9—C10	171.0 (10)
C4—N1—C5—N3	−177.9 (6)	O2—C8—C9—C10	−9.1 (13)
C2—C1—C5—N1	2.1 (12)	O1—C8—C9—N3	−7.1 (14)
Cl—C1—C5—N1	−176.5 (6)	O2—C8—C9—N3	172.8 (8)
C2—C1—C5—N3	175.8 (6)	N3—C9—C10—C11	0.9 (10)
Cl—C1—C5—N3	−2.8 (10)	C8—C9—C10—C11	−177.4 (9)
N2—N3—C5—N1	89.5 (9)	N3—N2—C11—C10	0.2 (10)
C9—N3—C5—N1	−91.0 (10)	N3—N2—C11—Br	179.4 (6)
N2—N3—C5—C1	−85.1 (9)	C9—C10—C11—N2	−0.7 (10)
C9—N3—C5—C1	94.4 (10)	C9—C10—C11—Br	−179.8 (6)