2-Chloro-N-[1-(4-chloro­phen­yl)-3-cyano-1H-pyrazol-5-yl]acetamide

Mu, H.; Yang, Y.; Jiang, Q.; Fu, X.; Wan, R.

doi:10.1107/S1600536812043966

organic compounds

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ISSN: 2056-9890

Volume 68| Part 11| November 2012| Page o3249

doi:10.1107/S1600536812043966

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2-Chloro-N-[1-(4-chlorophenyl)-3-cyano-1H-pyrazol-5-yl]acetamide

Hai-ping Mu,^a Yang Yang,^a Qiang-hua Jiang,^a Xiao-dong Fu ^a and Rong Wan ^a ^*

^aDepartment of Applied Chemistry, College of Science, Nanjing University of Technology, No. 5 Xinmofan Road, Nanjing, Nanjing 210009, People's Republic of China
^*Correspondence e-mail: rwan@njut.edu.cn

(Received 6 July 2012; accepted 23 October 2012; online 31 October 2012)

The title compound, C₁₂H₈Cl₂N₄O, was synthesized by the reaction of 5-amino-1-(4-chlorophenyl)-1H-pyrazole-3-carbonitrile and 2-chloroacetyl chloride. The dihedral angle between the pyrazole and benzene rings is 30.7 (3)°. In the crystal structure, strong N—H⋯O hydrogen bonds link the molecules into chains along [001]. C—H⋯N hydrogen bonds are also present.

Related literature

The title compound is important in the synthesis of derivatives of the insecticide Fipronil {systematic name: (RS)-5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-(trifluoromethylsulfinyl)-1H-pyrazole-3-carbonitrile}. For the biological activity of N-pyrazole derivatives, see: Zhao et al. (2010 ); Liu et al. (2010 ). For bond-length data, see: Allen et al. (1987 ). For the structure of 2-chloro-N-(3-cyano-1-(2,6-dichloro-4-(trifluoromethyl)phenyl)-1H-pyrazol-5-yl)acetamide, see: Zhang et al. (2012 ).

Experimental

Crystal data

C₁₂H₈Cl₂N₄O
M_r = 295.12
Orthorhombic, P n a 2₁
a = 18.493 (4) Å
b = 13.815 (3) Å
c = 5.060 (1) Å
V = 1292.7 (4) Å³
Z = 4
Mo Kα radiation
μ = 0.50 mm⁻¹
T = 293 K
0.30 × 0.20 × 0.10 mm

Data collection

Enraf–Nonius CAD-4 diffractometer
Absorption correction: ψ scan (North et al., 1968 ) T_min = 0.865, T_max = 0.952
2646 measured reflections
2606 independent reflections
2255 reflections with I > 2σ(I)
R_int = 0.024
3 standard reflections every 200 reflections intensity decay: 1%

Refinement

R[F² > 2σ(F²)] = 0.037
wR(F²) = 0.099
S = 1.01
2606 reflections
173 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 0.16 e Å⁻³
Δρ_min = −0.24 e Å⁻³
Absolute structure: Flack (1983 ), 1271 Friedel pairs
Flack parameter: 0.09 (9)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N3—H3A⋯Oⁱ	0.86	2.16	2.858 (3)	137
C12—H12C⋯N2ⁱⁱ	0.97	2.52	3.445 (3)	160
Symmetry codes: (i) x, y, z+1; (ii) $[-x+{\script{1\over 2}}, y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ .

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1989 ); 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); software used to prepare material for publication: SHELXS97.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536812043966/rn2106sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812043966/rn2106Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812043966/rn2106Isup3.cml

checkCIF report

Comment top

N-Pyrazole derivatives are of great interest because of their diverse biological activities such as insecticidal (Zhao et al., 2010) and antifungal activities (Liu et al., 2010). The title compound is an important intermediate in the synthesis of N-aromatic pyrazole derivatives. The molecular structure of (I) is shown in Fig.1. In this structure, bond length and angles are within the normal range (Allen et al., 1987) and the mean deviation from the plane(N1/N2/C9/C8/C7) is 0.0045 Å. The dihedral angle between the pyrazole and phenyl ring in compound (I) is 30.7 (3)°, which is smaller than the angle in the structure of 2-chloro-N- (3-cyano-1-(2,6-dichloro-4-(trifluoromethyl)phenyl)-1H-pyrazol-5-yl) acetamide (Zhang et al., 2012), which is 71.5 (3)°. While bond lengths of the two compounds are similar, the difference in the dihedral angle probably results from greater steric hindrance in the (trifluoromethyl)phenyl derivative. In the crystal structure, strong N—H···O hydrogen bonds link the molecules into infinite one-dimensional chains along the [001] direction. Intermolecular C—H···N and N—H···O hydrogen bonds (Table 1) may help to establish the molecular conformation of (I). (Fig. 2)

Related literature top

The title compound is an important compound in the synthesis of derivatives of the insecticide Fipronil {systematic name: (RS)-5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-(trifluoromethylsulfinyl)-1H-pyrazole-3-carbonitrile}. For the biological activity of N-pyrazole derivatives, see: Zhao et al. (2010); Liu et al. (2010). For bond-length data, see: Allen et al. (1987). For the structure of 2-chloro-N-(3-cyano-1-(2,6-dichloro-4-(trifluoromethyl)phenyl)-1H-pyrazol-5-yl)acetamide, see: Zhang et al. (2012).

Experimental top

To a stirred solution of 5-amino-1-(4-chlorophenyl)-1H-pyrazole-3-carbonitrile (5 mmol) in THF (20 ml) was added 2-chloroacetyl chloride (5 mmol) dropwise at 0–5°C. During the addition, the solution is cooled in an ice-salt bath. After the cooling bath had been removed, the reaction mixture was allowed to stand for 2 h at room temperature. The crude product (I) precipitated and was filtered. Pure compound (I) was obtained by crystallization from ethanol. Crystals of (I) suitable for X-ray diffraction were obtained by slow evaporation of an acetone solution.

Computing details top

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1989); cell refinement: CAD-4 EXPRESS (Enraf–Nonius, 1989); 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: SHELXS97 (Sheldrick, 2008).

Figures top

	Fig. 1. A view of the molecular structure of (I). Displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. Partial packing view showing the hydrogen-bonded network. Dashed lines indicate intermolecular N—H···O and C—H···N hydrogen bonds.

2-Chloro-N-[1-(4-chlorophenyl)-3-cyano-1H-pyrazol-5-yl]acetamide top

Crystal data top

C₁₂H₈Cl₂N₄O	D_x = 1.516 Mg m⁻³
M_r = 295.12	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Pna2₁	Cell parameters from 25 reflections
a = 18.493 (4) Å	θ = 9–13°
b = 13.815 (3) Å	µ = 0.50 mm⁻¹
c = 5.060 (1) Å	T = 293 K
V = 1292.7 (4) Å³	Block, colorless
Z = 4	0.30 × 0.20 × 0.10 mm
F(000) = 600

Data collection top

Enraf–Nonius CAD-4 diffractometer	2255 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.024
Graphite monochromator	θ_max = 25.4°, θ_min = 2.2°
ω/2θ scans	h = −22→22
Absorption correction: ψ scan (North et al., 1968)	k = 0→16
T_min = 0.865, T_max = 0.952	l = −6→0
2646 measured reflections	3 standard reflections every 200 reflections
2606 independent reflections	intensity decay: 1%

Refinement top

Refinement on F²	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.037	w = 1/[σ²(F_o²) + (0.064P)²] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.099	(Δ/σ)_max < 0.001
S = 1.01	Δρ_max = 0.16 e Å⁻³
2606 reflections	Δρ_min = −0.24 e Å⁻³
173 parameters	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
1 restraint	Extinction coefficient: 0.023 (2)
Primary atom site location: structure-invariant direct methods	Absolute structure: Flack (1983), 1271 Friedel pairs
Secondary atom site location: difference Fourier map	Absolute structure parameter: 0.09 (9)

Crystal data top

C₁₂H₈Cl₂N₄O	V = 1292.7 (4) Å³
M_r = 295.12	Z = 4
Orthorhombic, Pna2₁	Mo Kα radiation
a = 18.493 (4) Å	µ = 0.50 mm⁻¹
b = 13.815 (3) Å	T = 293 K
c = 5.060 (1) Å	0.30 × 0.20 × 0.10 mm

Data collection top

Enraf–Nonius CAD-4 diffractometer	2255 reflections with I > 2σ(I)
Absorption correction: ψ scan (North et al., 1968)	R_int = 0.024
T_min = 0.865, T_max = 0.952	3 standard reflections every 200 reflections
2646 measured reflections	intensity decay: 1%
2606 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.037	H-atom parameters constrained
wR(F²) = 0.099	Δρ_max = 0.16 e Å⁻³
S = 1.01	Δρ_min = −0.24 e Å⁻³
2606 reflections	Absolute structure: Flack (1983), 1271 Friedel pairs
173 parameters	Absolute structure parameter: 0.09 (9)
1 restraint

Special details top

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 (Å²) top

	x	y	z	U_iso*/U_eq
O	0.20761 (11)	0.90238 (15)	−0.4786 (4)	0.0473 (5)
Cl1	0.07270 (4)	0.51152 (5)	0.76028 (19)	0.0634 (3)
N1	0.27787 (9)	0.73978 (13)	0.1128 (5)	0.0330 (5)
C1	0.25223 (13)	0.63629 (18)	0.4875 (6)	0.0385 (6)
H1A	0.3011	0.6381	0.5309	0.046*
Cl2	0.07546 (4)	0.99063 (6)	0.07496 (17)	0.0548 (2)
N2	0.34595 (10)	0.70361 (14)	0.0940 (6)	0.0397 (5)
C2	0.20505 (14)	0.58124 (18)	0.6366 (6)	0.0428 (7)
H2B	0.2220	0.5449	0.7785	0.051*
N3	0.20572 (11)	0.87436 (15)	−0.0382 (5)	0.0339 (5)
H3A	0.1824	0.8829	0.1070	0.041*
C3	0.13257 (15)	0.58071 (18)	0.5729 (6)	0.0432 (6)
C4	0.10698 (14)	0.63335 (19)	0.3602 (7)	0.0442 (7)
H4A	0.0579	0.6325	0.3198	0.053*
N4	0.51184 (12)	0.73394 (18)	−0.1943 (8)	0.0707 (9)
C5	0.15393 (13)	0.68719 (18)	0.2079 (6)	0.0407 (6)
H5A	0.1370	0.7220	0.0632	0.049*
C6	0.22697 (12)	0.68864 (16)	0.2739 (6)	0.0330 (6)
C7	0.27029 (12)	0.82144 (17)	−0.0352 (5)	0.0329 (6)
C8	0.33442 (12)	0.83866 (18)	−0.1594 (6)	0.0388 (6)
H8A	0.3457	0.8887	−0.2752	0.047*
C9	0.37887 (13)	0.76412 (17)	−0.0731 (6)	0.0390 (6)
C10	0.45341 (15)	0.74665 (18)	−0.1393 (8)	0.0492 (8)
C11	0.17925 (12)	0.91243 (17)	−0.2649 (5)	0.0314 (5)
C12	0.10972 (13)	0.96827 (18)	−0.2494 (6)	0.0357 (6)
H12B	0.0732	0.9332	−0.3483	0.043*
H12C	0.1168	1.0301	−0.3365	0.043*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O	0.0494 (11)	0.0672 (14)	0.0253 (11)	0.0153 (10)	0.0035 (9)	0.0035 (9)
Cl1	0.0730 (5)	0.0656 (5)	0.0516 (5)	−0.0249 (4)	0.0147 (5)	0.0028 (5)
N1	0.0321 (10)	0.0332 (10)	0.0337 (13)	0.0041 (8)	−0.0021 (10)	−0.0001 (11)
C1	0.0422 (14)	0.0375 (14)	0.0358 (16)	0.0021 (11)	−0.0055 (13)	−0.0011 (12)
Cl2	0.0469 (4)	0.0817 (5)	0.0359 (4)	0.0234 (3)	0.0066 (4)	−0.0023 (4)
N2	0.0315 (10)	0.0376 (10)	0.0499 (15)	0.0067 (8)	−0.0030 (11)	0.0018 (13)
C2	0.0568 (16)	0.0392 (13)	0.0324 (16)	0.0039 (12)	−0.0011 (13)	0.0053 (13)
N3	0.0391 (11)	0.0391 (12)	0.0235 (11)	0.0119 (9)	0.0029 (10)	0.0032 (10)
C3	0.0561 (16)	0.0395 (13)	0.0341 (15)	−0.0064 (11)	0.0088 (15)	−0.0043 (14)
C4	0.0385 (14)	0.0512 (16)	0.0430 (17)	−0.0066 (12)	0.0014 (14)	−0.0034 (15)
N4	0.0401 (14)	0.0684 (16)	0.104 (3)	0.0034 (11)	0.0086 (17)	0.008 (2)
C5	0.0430 (14)	0.0443 (14)	0.0348 (16)	0.0042 (11)	−0.0031 (12)	0.0025 (13)
C6	0.0360 (12)	0.0303 (11)	0.0328 (14)	0.0022 (9)	0.0007 (11)	−0.0015 (12)
C7	0.0346 (12)	0.0344 (13)	0.0298 (13)	0.0039 (10)	−0.0011 (12)	−0.0003 (12)
C8	0.0409 (13)	0.0370 (13)	0.0384 (16)	0.0004 (11)	0.0043 (13)	0.0043 (13)
C9	0.0324 (12)	0.0382 (13)	0.0465 (17)	−0.0010 (11)	0.0011 (13)	−0.0002 (13)
C10	0.0397 (14)	0.0411 (15)	0.067 (2)	−0.0002 (11)	0.0052 (15)	0.0078 (16)
C11	0.0344 (12)	0.0338 (12)	0.0259 (13)	0.0009 (9)	−0.0002 (12)	0.0016 (12)
C12	0.0366 (12)	0.0425 (13)	0.0279 (13)	0.0059 (10)	−0.0019 (12)	0.0030 (13)

Geometric parameters (Å, º) top

O—C11	1.210 (3)	N3—H3A	0.8600
Cl1—C3	1.743 (3)	C3—C4	1.382 (4)
N1—N2	1.358 (2)	C4—C5	1.379 (4)
N1—C7	1.361 (3)	C4—H4A	0.9300
N1—C6	1.431 (3)	N4—C10	1.129 (3)
C1—C6	1.382 (4)	C5—C6	1.391 (3)
C1—C2	1.382 (4)	C5—H5A	0.9300
C1—H1A	0.9300	C7—C8	1.363 (3)
Cl2—C12	1.786 (3)	C8—C9	1.388 (3)
N2—C9	1.336 (4)	C8—H8A	0.9300
C2—C3	1.379 (4)	C9—C10	1.439 (4)
C2—H2B	0.9300	C11—C12	1.502 (3)
N3—C11	1.354 (3)	C12—H12B	0.9700
N3—C7	1.400 (3)	C12—H12C	0.9700

N2—N1—C7	111.21 (19)	C1—C6—C5	120.6 (2)
N2—N1—C6	117.91 (19)	C1—C6—N1	118.8 (2)
C7—N1—C6	130.88 (18)	C5—C6—N1	120.6 (2)
C6—C1—C2	120.1 (2)	N1—C7—C8	108.0 (2)
C6—C1—H1A	119.9	N1—C7—N3	121.8 (2)
C2—C1—H1A	119.9	C8—C7—N3	130.2 (2)
C9—N2—N1	103.70 (19)	C7—C8—C9	103.9 (2)
C3—C2—C1	119.3 (3)	C7—C8—H8A	128.0
C3—C2—H2B	120.4	C9—C8—H8A	128.0
C1—C2—H2B	120.4	N2—C9—C8	113.2 (2)
C11—N3—C7	121.4 (2)	N2—C9—C10	118.6 (2)
C11—N3—H3A	119.3	C8—C9—C10	128.2 (3)
C7—N3—H3A	119.3	N4—C10—C9	179.0 (4)
C2—C3—C4	120.8 (3)	O—C11—N3	123.8 (2)
C2—C3—Cl1	119.6 (2)	O—C11—C12	118.5 (2)
C4—C3—Cl1	119.6 (2)	N3—C11—C12	117.7 (2)
C5—C4—C3	120.2 (2)	C11—C12—Cl2	116.15 (19)
C5—C4—H4A	119.9	C11—C12—H12B	108.2
C3—C4—H4A	119.9	Cl2—C12—H12B	108.2
C4—C5—C6	119.0 (3)	C11—C12—H12C	108.2
C4—C5—H5A	120.5	Cl2—C12—H12C	108.2
C6—C5—H5A	120.5	H12B—C12—H12C	107.4

C7—N1—N2—C9	−1.3 (3)	C6—N1—C7—C8	−177.8 (3)
C6—N1—N2—C9	178.0 (2)	N2—N1—C7—N3	−177.1 (2)
C6—C1—C2—C3	−1.2 (4)	C6—N1—C7—N3	3.8 (4)
C1—C2—C3—C4	0.9 (4)	C11—N3—C7—N1	−139.4 (3)
C1—C2—C3—Cl1	−179.9 (2)	C11—N3—C7—C8	42.6 (4)
C2—C3—C4—C5	0.2 (4)	N1—C7—C8—C9	−0.7 (3)
Cl1—C3—C4—C5	−179.0 (2)	N3—C7—C8—C9	177.5 (3)
C3—C4—C5—C6	−0.9 (4)	N1—N2—C9—C8	0.8 (3)
C2—C1—C6—C5	0.5 (4)	N1—N2—C9—C10	−179.9 (3)
C2—C1—C6—N1	−175.9 (2)	C7—C8—C9—N2	−0.1 (3)
C4—C5—C6—C1	0.5 (4)	C7—C8—C9—C10	−179.3 (3)
C4—C5—C6—N1	176.9 (2)	N2—C9—C10—N4	169 (22)
N2—N1—C6—C1	29.2 (3)	C8—C9—C10—N4	−12 (22)
C7—N1—C6—C1	−151.8 (3)	C7—N3—C11—O	1.6 (4)
N2—N1—C6—C5	−147.2 (2)	C7—N3—C11—C12	−179.9 (2)
C7—N1—C6—C5	31.8 (4)	O—C11—C12—Cl2	−174.0 (2)
N2—N1—C7—C8	1.3 (3)	N3—C11—C12—Cl2	7.4 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3A···Oⁱ	0.86	2.16	2.858 (3)	137
C12—H12C···N2ⁱⁱ	0.97	2.52	3.445 (3)	160

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

Experimental details

Crystal data
Chemical formula	C₁₂H₈Cl₂N₄O
M_r	295.12
Crystal system, space group	Orthorhombic, Pna2₁
Temperature (K)	293
a, b, c (Å)	18.493 (4), 13.815 (3), 5.060 (1)
V (Å³)	1292.7 (4)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.50
Crystal size (mm)	0.30 × 0.20 × 0.10

Data collection
Diffractometer	Enraf–Nonius CAD-4 diffractometer
Absorption correction	ψ scan (North et al., 1968)
T_min, T_max	0.865, 0.952
No. of measured, independent and observed [I > 2σ(I)] reflections	2646, 2606, 2255
R_int	0.024
(sin θ/λ)_max (Å⁻¹)	0.604

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.037, 0.099, 1.01
No. of reflections	2606
No. of parameters	173
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.16, −0.24
Absolute structure	Flack (1983), 1271 Friedel pairs
Absolute structure parameter	0.09 (9)

Computer programs: CAD-4 EXPRESS (Enraf–Nonius, 1989), XCAD4 (Harms & Wocadlo, 1995), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3A···Oⁱ	0.8600	2.1600	2.858 (3)	137.00
C12—H12C···N2ⁱⁱ	0.9700	2.5200	3.445 (3)	160.00

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

Acknowledgements

The authors thank the Science and Technology Project of Jiangsu Province (No. BE2011352) for financial support and acknowledge the help of members of the laboratory.

References

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