4-Bromo-1-[2,6-dichloro-4-(trifluoro­meth­yl)phen­yl]-5-(4-nitro­benzyl­idene­amino)-1H-pyrazole-3-carbonitrile

Yang, Z.; Li, S.

doi:10.1107/S160053680800545X

organic compounds

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ISSN: 2056-9890

Volume 64| Part 3| March 2008| Page o645

doi:10.1107/S160053680800545X

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4-Bromo-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-5-(4-nitrobenzylideneamino)-1H-pyrazole-3-carbonitrile

Zhiping Yang ^a and Shuyan Li ^a ^*

^aDepartment of Food and Biotechnology, Zhangzhou Vocational Technical College, 363000 Zhangzhou, People's Republic of China
^*Correspondence e-mail: lisy910@163.com

(Received 16 December 2007; accepted 26 February 2008; online 29 February 2008)

The title compound, C₁₈H₇BrCl₂F₃N₅O₂, is an L-shaped tricyclic imine. The pyrazole ring is essentially coplanar with the nitro-substituted benzene ring [dihedral angle = 3.6 (2)°] and approximately perpendicular to the trifluoromethylsubstituted ring [dihedral angle = 88.5 (2)°].

Related literature

For related literature, see: Philippe (1997 , 2000 ); Zhong et al. (2005 ).

Experimental

Crystal data

C₁₈H₇BrCl₂F₃N₅O₂
M_r = 533.10
Monoclinic, P 2₁ /n
a = 8.0925 (7) Å
b = 13.0406 (10) Å
c = 19.7165 (16) Å
β = 100.753 (2)°
V = 2044.2 (3) Å³
Z = 4
Mo Kα radiation
μ = 2.33 mm⁻¹
T = 298 (2) K
0.27 × 0.24 × 0.22 mm

Data collection

Bruker APEX area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2002 ) T_min = 0.572, T_max = 0.629
12155 measured reflections
4437 independent reflections
3331 reflections with I > 2σ(I)
R_int = 0.024

Refinement

R[F² > 2σ(F²)] = 0.041
wR(F²) = 0.110
S = 1.07
4437 reflections
280 parameters
H-atom parameters constrained
Δρ_max = 0.56 e Å⁻³
Δρ_min = −0.38 e Å⁻³

Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT; 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.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S160053680800545X/fl2181sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053680800545X/fl2181Isup2.hkl

checkCIF report

Comment top

The title compound, (I) (Fig. 1), is similar to the effective insecticides used to treat animals such as cows and sheep (Philippe, 1997, 2000). Earlier we reported on a structure with the same ring system but without the Br substituent on the pyrazole ring (Zhong et al., 2005). That molecule had an overall U shape and exhibited some π-π interactions between the pyrazole and nitro benzene rings. (I) has an overall L shape with the pyrazole ring being essentially coplanar with the nitro benzene ring (dihedral angle of 3.6 (2)°) and approximately perpendicular to the trifluoro phenyl ring (dihedral angle of 88.5 (2)°) and it shows no π-π interactions in the molecular packing. All bond lengths and angles are normal.

Related literature top

For related literature, see: Philippe (1997, 2000); Zhong et al. (2005).

Experimental top

The method of Zhong et al. (2005) was used to prepare 5-amino- 3-cyano-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]pyrazole(2.5 mmol). This was followed by reaction with 4-nitrobenzaldehyde(2.5 mmol) and hydrochloric acid(2 ml) in anhydrous ethanol(5 ml) to obtain 1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-3-cyano- 5-[(4-nitrophenyl)methyleneamino]-1H-pyrazole, which was then reacted with N-bromosuccinimide(1.5 mmol) (Philippe, 2000) in acetonitrile (6 mL) at room temperature. After being stirred a few minutes, the reaction was monitored by TLC until all starting materials were consumed. Finally, the reaction mixture was evaporated under reduced pressure to provide the required crude product, which was then partitioned between dichloromethane and water. Seperating and drying the organic phase and evaporating it under reduced pressure gave the title compound (88.5% yield). Colourless single crystals suitable for X-ray analysis were obtained by slow evaporation of an anhydrous ethanol-acetone (2:1) solution of (I) (m.p. 463–465 K). IR (KBr, ν cm^-1): 3396, 2244, 1623, 1596, 1525, 1384, 1310, 1135, 877, 817; ¹H NMR (C₃D₆O, δ, p.p.m.): 9.60 (s, 1H), 8.34 (s, 2H), 8.16(d, 2H), 8.13 (d, 2H); ¹³C NMR (C₃D₆O, δ, p.p.m.): 166.4, 151.5, 147.7, 140.7, 137.4, 136.4, 134.6 (q, J = 34.1 Hz), 131.4(2 C), 130.3, 127.2 (2 C), 127.1 (2 C), 124.9(2 C), 121.4 (q, J = 271.1 Hz), 112.3.

Computing details top

Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT (Bruker, 2002); 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 (Sheldrick, 2008).

Figures top

Fig. 1. The molecular structure of (I) showing the atom numbering scheme and displacement ellipsoids at 50% probability level.

4-Bromo-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]- 5-(4-nitrobenzylideneamino)-1H-pyrazole-3-carbonitrile top

Crystal data top

C₁₈H₇BrCl₂F₃N₅O₂	F(000) = 1048
M_r = 533.10	D_x = 1.732 Mg m⁻³
Monoclinic, P2₁/n	Melting point = 463–465 K
Hall symbol: -P 2yn	Mo Kα radiation, λ = 0.71073 Å
a = 8.0925 (7) Å	Cell parameters from 3580 reflections
b = 13.0406 (10) Å	θ = 2.6–24.2°
c = 19.7165 (16) Å	µ = 2.33 mm⁻¹
β = 100.753 (2)°	T = 298 K
V = 2044.2 (3) Å³	Blcok, colorless
Z = 4	0.27 × 0.24 × 0.22 mm

Data collection top

Bruker APEX area-detector diffractometer	4437 independent reflections
Radiation source: fine-focus sealed tube	3331 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.024
ϕ and ω scans	θ_max = 27.0°, θ_min = 1.9°
Absorption correction: multi-scan (SADABS; Bruker, 2002)	h = −7→10
T_min = 0.572, T_max = 0.629	k = −15→16
12155 measured reflections	l = −25→19

Refinement top

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)] = 0.041	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.110	H-atom parameters constrained
S = 1.07	w = 1/[σ²(F_o²) + (0.059P)²] where P = (F_o² + 2F_c²)/3
4437 reflections	(Δ/σ)_max = 0.004
280 parameters	Δρ_max = 0.56 e Å⁻³
0 restraints	Δρ_min = −0.38 e Å⁻³

Crystal data top

C₁₈H₇BrCl₂F₃N₅O₂	V = 2044.2 (3) Å³
M_r = 533.10	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 8.0925 (7) Å	µ = 2.33 mm⁻¹
b = 13.0406 (10) Å	T = 298 K
c = 19.7165 (16) Å	0.27 × 0.24 × 0.22 mm
β = 100.753 (2)°

Data collection top

Bruker APEX area-detector diffractometer	4437 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2002)	3331 reflections with I > 2σ(I)
T_min = 0.572, T_max = 0.629	R_int = 0.024
12155 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.041	0 restraints
wR(F²) = 0.110	H-atom parameters constrained
S = 1.07	Δρ_max = 0.56 e Å⁻³
4437 reflections	Δρ_min = −0.38 e Å⁻³
280 parameters

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
Br1	−0.24016 (4)	0.51690 (2)	0.761142 (16)	0.05284 (13)
Cl1	0.30689 (11)	0.82810 (7)	0.73346 (4)	0.0691 (2)
Cl2	−0.11238 (11)	0.88488 (7)	0.91210 (4)	0.0726 (3)
F1	0.5843 (3)	1.0868 (2)	0.92604 (16)	0.1220 (10)
F2	0.3925 (4)	1.19099 (18)	0.89073 (15)	0.1444 (13)
F3	0.4114 (4)	1.12171 (18)	0.98766 (12)	0.1088 (9)
O1	0.5960 (3)	0.4599 (3)	1.17024 (13)	0.0896 (8)
O2	0.4901 (5)	0.3126 (3)	1.14333 (19)	0.1335 (14)
N1	0.0002 (3)	0.78718 (16)	0.79313 (11)	0.0449 (5)
N2	−0.1070 (3)	0.81212 (17)	0.73411 (12)	0.0509 (6)
N3	−0.4315 (4)	0.7201 (2)	0.61178 (18)	0.0856 (10)
N4	0.0797 (3)	0.65801 (17)	0.87633 (11)	0.0467 (5)
N5	0.4987 (4)	0.4039 (3)	1.13390 (16)	0.0754 (8)
C1	0.4224 (5)	1.1057 (3)	0.92265 (17)	0.0655 (9)
C2	0.3130 (4)	1.0194 (2)	0.89024 (15)	0.0510 (7)
C3	0.3571 (4)	0.9687 (2)	0.83475 (15)	0.0538 (7)
H3	0.4544	0.9866	0.8189	0.065*
C4	0.2546 (4)	0.8908 (2)	0.80309 (13)	0.0469 (6)
C5	0.1103 (3)	0.86405 (19)	0.82729 (13)	0.0437 (6)
C6	0.0705 (3)	0.9163 (2)	0.88322 (14)	0.0488 (6)
C7	0.1700 (4)	0.9942 (2)	0.91509 (16)	0.0521 (7)
H7	0.1417	1.0290	0.9525	0.062*
C8	−0.3258 (4)	0.7239 (2)	0.65789 (17)	0.0581 (8)
C9	−0.1943 (4)	0.7263 (2)	0.71809 (14)	0.0469 (6)
C10	−0.1445 (3)	0.6474 (2)	0.76518 (14)	0.0436 (6)
C11	−0.0177 (3)	0.6883 (2)	0.81450 (13)	0.0427 (6)
C12	0.0866 (4)	0.5653 (2)	0.89369 (15)	0.0538 (7)
H12	0.0246	0.5182	0.8638	0.065*
C13	0.1866 (4)	0.5268 (2)	0.95842 (15)	0.0482 (7)
C14	0.1918 (4)	0.4225 (2)	0.96947 (17)	0.0607 (8)
H14	0.1278	0.3790	0.9375	0.073*
C15	0.2915 (4)	0.3823 (3)	1.02788 (18)	0.0652 (9)
H15	0.2954	0.3119	1.0357	0.078*
C16	0.3844 (4)	0.4479 (3)	1.07395 (15)	0.0546 (7)
C17	0.3788 (4)	0.5522 (3)	1.06511 (15)	0.0578 (7)
H17	0.4417	0.5952	1.0977	0.069*
C18	0.2781 (4)	0.5918 (2)	1.00707 (15)	0.0535 (7)
H18	0.2714	0.6624	1.0005	0.064*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.0565 (2)	0.04456 (18)	0.0567 (2)	−0.00804 (13)	0.00875 (13)	−0.00358 (13)
Cl1	0.0809 (6)	0.0743 (6)	0.0569 (5)	0.0042 (5)	0.0252 (4)	−0.0109 (4)
Cl2	0.0723 (5)	0.0821 (6)	0.0717 (5)	−0.0225 (4)	0.0347 (4)	−0.0172 (4)
F1	0.0760 (16)	0.126 (2)	0.158 (3)	−0.0348 (16)	0.0070 (15)	−0.0421 (19)
F2	0.199 (3)	0.0628 (14)	0.136 (2)	−0.0535 (17)	−0.061 (2)	0.0372 (15)
F3	0.145 (2)	0.1075 (18)	0.0751 (15)	−0.0630 (17)	0.0242 (14)	−0.0331 (13)
O1	0.0723 (17)	0.137 (3)	0.0546 (15)	0.0176 (17)	0.0000 (13)	0.0003 (17)
O2	0.166 (3)	0.101 (2)	0.113 (3)	0.027 (2)	−0.026 (2)	0.045 (2)
N1	0.0517 (13)	0.0395 (12)	0.0419 (12)	−0.0013 (10)	0.0048 (10)	0.0010 (9)
N2	0.0591 (15)	0.0435 (13)	0.0465 (13)	0.0051 (11)	0.0004 (11)	−0.0022 (10)
N3	0.081 (2)	0.080 (2)	0.082 (2)	0.0017 (17)	−0.0216 (18)	0.0013 (17)
N4	0.0533 (13)	0.0445 (13)	0.0422 (12)	−0.0015 (11)	0.0084 (10)	0.0041 (10)
N5	0.077 (2)	0.093 (2)	0.0571 (18)	0.0245 (19)	0.0151 (15)	0.0174 (18)
C1	0.073 (2)	0.062 (2)	0.059 (2)	−0.0211 (17)	0.0039 (16)	0.0027 (16)
C2	0.0598 (19)	0.0473 (15)	0.0438 (16)	−0.0091 (13)	0.0048 (13)	0.0050 (13)
C3	0.0537 (18)	0.0585 (18)	0.0501 (17)	−0.0082 (14)	0.0125 (13)	0.0068 (14)
C4	0.0545 (16)	0.0482 (16)	0.0383 (14)	0.0027 (13)	0.0094 (12)	0.0007 (12)
C5	0.0527 (16)	0.0368 (14)	0.0400 (14)	−0.0006 (12)	0.0050 (11)	0.0003 (11)
C6	0.0515 (16)	0.0502 (16)	0.0454 (15)	−0.0058 (13)	0.0110 (12)	−0.0012 (12)
C7	0.0639 (19)	0.0473 (16)	0.0452 (17)	−0.0051 (13)	0.0107 (14)	−0.0064 (12)
C8	0.0629 (19)	0.0487 (17)	0.0580 (19)	0.0000 (14)	−0.0008 (16)	−0.0009 (14)
C9	0.0501 (16)	0.0427 (15)	0.0466 (16)	0.0030 (13)	0.0056 (12)	−0.0041 (12)
C10	0.0467 (15)	0.0389 (14)	0.0454 (15)	−0.0012 (12)	0.0092 (11)	−0.0040 (11)
C11	0.0499 (15)	0.0367 (13)	0.0437 (15)	0.0006 (12)	0.0142 (12)	0.0011 (11)
C12	0.0571 (18)	0.0459 (16)	0.0546 (18)	−0.0024 (14)	0.0008 (13)	0.0003 (13)
C13	0.0485 (16)	0.0471 (16)	0.0487 (16)	−0.0013 (13)	0.0085 (12)	0.0050 (13)
C14	0.0630 (19)	0.0482 (17)	0.066 (2)	−0.0078 (15)	−0.0009 (15)	0.0060 (14)
C15	0.073 (2)	0.0504 (18)	0.073 (2)	0.0031 (16)	0.0138 (17)	0.0167 (16)
C16	0.0543 (17)	0.0666 (19)	0.0442 (16)	0.0074 (15)	0.0126 (13)	0.0091 (14)
C17	0.0634 (19)	0.0645 (19)	0.0441 (16)	0.0011 (16)	0.0067 (13)	−0.0040 (14)
C18	0.0657 (19)	0.0458 (16)	0.0490 (17)	0.0014 (14)	0.0106 (14)	−0.0009 (13)

Geometric parameters (Å, º) top

Br1—C10	1.865 (3)	C3—H3	0.9300
Cl1—C4	1.717 (3)	C4—C5	1.386 (4)
Cl2—C6	1.731 (3)	C5—C6	1.384 (4)
F1—C1	1.322 (4)	C6—C7	1.374 (4)
F2—C1	1.279 (4)	C7—H7	0.9300
F3—C1	1.318 (4)	C8—C9	1.439 (4)
O1—N5	1.206 (4)	C9—C10	1.394 (4)
O2—N5	1.209 (4)	C10—C11	1.382 (4)
N1—N2	1.355 (3)	C12—C13	1.466 (4)
N1—C11	1.373 (3)	C12—H12	0.9300
N1—C5	1.424 (3)	C13—C14	1.378 (4)
N2—C9	1.330 (3)	C13—C18	1.386 (4)
N3—C8	1.127 (4)	C14—C15	1.380 (4)
N4—C12	1.256 (3)	C14—H14	0.9300
N4—C11	1.380 (3)	C15—C16	1.366 (5)
N5—C16	1.474 (4)	C15—H15	0.9300
C1—C2	1.499 (4)	C16—C17	1.371 (5)
C2—C7	1.377 (5)	C17—C18	1.375 (4)
C2—C3	1.381 (4)	C17—H17	0.9300
C3—C4	1.384 (4)	C18—H18	0.9300

N2—N1—C11	113.7 (2)	N3—C8—C9	177.9 (4)
N2—N1—C5	118.7 (2)	N2—C9—C10	112.8 (2)
C11—N1—C5	127.5 (2)	N2—C9—C8	119.5 (2)
C9—N2—N1	103.2 (2)	C10—C9—C8	127.6 (3)
C12—N4—C11	120.3 (2)	C11—C10—C9	105.6 (2)
O1—N5—O2	123.7 (3)	C11—C10—Br1	129.0 (2)
O1—N5—C16	118.9 (3)	C9—C10—Br1	125.4 (2)
O2—N5—C16	117.4 (4)	N1—C11—N4	117.6 (2)
F2—C1—F3	107.5 (3)	N1—C11—C10	104.7 (2)
F2—C1—F1	106.3 (3)	N4—C11—C10	137.6 (2)
F3—C1—F1	103.1 (3)	N4—C12—C13	123.8 (3)
F2—C1—C2	113.6 (3)	N4—C12—H12	118.1
F3—C1—C2	113.1 (3)	C13—C12—H12	118.1
F1—C1—C2	112.5 (3)	C14—C13—C18	119.8 (3)
C7—C2—C3	121.7 (3)	C14—C13—C12	118.1 (3)
C7—C2—C1	119.7 (3)	C18—C13—C12	122.1 (3)
C3—C2—C1	118.5 (3)	C13—C14—C15	120.2 (3)
C2—C3—C4	119.1 (3)	C13—C14—H14	119.9
C2—C3—H3	120.4	C15—C14—H14	119.9
C4—C3—H3	120.4	C16—C15—C14	118.7 (3)
C3—C4—C5	120.1 (3)	C16—C15—H15	120.6
C3—C4—Cl1	119.6 (2)	C14—C15—H15	120.6
C5—C4—Cl1	120.3 (2)	C15—C16—C17	122.4 (3)
C6—C5—C4	119.1 (2)	C15—C16—N5	118.3 (3)
C6—C5—N1	120.4 (2)	C17—C16—N5	119.2 (3)
C4—C5—N1	120.5 (2)	C16—C17—C18	118.6 (3)
C7—C6—C5	121.6 (3)	C16—C17—H17	120.7
C7—C6—Cl2	119.3 (2)	C18—C17—H17	120.7
C5—C6—Cl2	119.1 (2)	C17—C18—C13	120.2 (3)
C6—C7—C2	118.3 (3)	C17—C18—H18	119.9
C6—C7—H7	120.9	C13—C18—H18	119.9
C2—C7—H7	120.9

Experimental details

Crystal data
Chemical formula	C₁₈H₇BrCl₂F₃N₅O₂
M_r	533.10
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	298
a, b, c (Å)	8.0925 (7), 13.0406 (10), 19.7165 (16)
β (°)	100.753 (2)
V (Å³)	2044.2 (3)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	2.33
Crystal size (mm)	0.27 × 0.24 × 0.22

Data collection
Diffractometer	Bruker APEX area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2002)
T_min, T_max	0.572, 0.629
No. of measured, independent and observed [I > 2σ(I)] reflections	12155, 4437, 3331
R_int	0.024
(sin θ/λ)_max (Å⁻¹)	0.639

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.041, 0.110, 1.07
No. of reflections	4437
No. of parameters	280
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.56, −0.38

Computer programs: SMART (Bruker, 2002), SAINT (Bruker, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Selected geometric parameters (Å, º) top

Br1—C10	1.865 (3)	N4—C12	1.256 (3)
N1—N2	1.355 (3)	N4—C11	1.380 (3)
N1—C11	1.373 (3)	C8—C9	1.439 (4)
N1—C5	1.424 (3)	C9—C10	1.394 (4)
N2—C9	1.330 (3)	C10—C11	1.382 (4)
N3—C8	1.127 (4)

N2—N1—C11	113.7 (2)	C10—C9—C8	127.6 (3)
N2—N1—C5	118.7 (2)	C11—C10—C9	105.6 (2)
C11—N1—C5	127.5 (2)	C11—C10—Br1	129.0 (2)
C9—N2—N1	103.2 (2)	C9—C10—Br1	125.4 (2)
C12—N4—C11	120.3 (2)	N1—C11—N4	117.6 (2)
N3—C8—C9	177.9 (4)	N1—C11—C10	104.7 (2)
N2—C9—C10	112.8 (2)	N4—C11—C10	137.6 (2)
N2—C9—C8	119.5 (2)	N4—C12—C13	123.8 (3)

Acknowledgements

This work was supported by the Natural Science Foundation of Fujian Province (No. B0610033).

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