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ISSN: 2056-9890

(Z)-4-[(2-Amino-4,5-di­chloro­anilino)(phenyl)methyl­­idene]-3-methyl-1-phenyl-1H-pyrazol-5(4H)-one

aCollege of Chemical Engineering, Northwest University, Xi'an 710069, Shannxi, People's Republic of China, and bCollege of Chemistry and Chemical Engineering, Xian University of Science and Technology, Xi'an 710054, Shannxi, People's Republic of China
*Correspondence e-mail: lvxq@nwu.edu.cn

(Received 1 August 2012; accepted 28 September 2012; online 20 October 2012)

The mol­ecule of the title compound, C23H18Cl2N4O, assumes a non-planar conformation in which the pyrazolone ring forms dihedral angles of 32.61 (19), 76.73 (14) and 52.57 (19)° with the three benzene rings. The secondary amino group is involved in an intra­molecular N—H⋯O hydrogen bond. In the crystal, mol­ecules are linked by pairs of N—H⋯O hydrogen bonds, forming inversion dimers. An offset stacking inter­action is observed between the chloro-substituted benzene rings protruding on both sides of these dimers [centroid–centroid distance = 3.862 (1) Å].

Related literature

For related structures, see: Lu et al. (2011[Lu, R., Xia, H., Lü, X. & Zhao, S. (2011). Acta Cryst. E67, o2701.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc., Perkin Trans. 2, pp. S1-S19.]). For the catalytic properties of asymmetric Schiff bases, see: Caboni et al. (2012[Caboni, L., Kinsella, G. K., Blanco, F., Fayne, D., Jagoe, W. N., Carr, M., Williams, D. C., Meegan, M. J. & Lloyd, D. G. (2012). J. Med. Chem. 55, 1635-1644.]). For the synthesis, see: Hennig & Mann (1988[Hennig, L. & Mann, G. (1988). Z. Chem. 28, 364-365.]).

[Scheme 1]

Experimental

Crystal data
  • C23H18Cl2N4O

  • Mr = 437.31

  • Triclinic, [P \overline 1]

  • a = 8.0653 (16) Å

  • b = 10.931 (2) Å

  • c = 13.851 (3) Å

  • α = 111.627 (3)°

  • β = 90.775 (3)°

  • γ = 110.226 (3)°

  • V = 1051.1 (4) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.33 mm−1

  • T = 296 K

  • 0.30 × 0.21 × 0.18 mm

Data collection
  • Bruker SMART 1K CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2004[Sheldrick, G. M. (2004). SADABS. University of Göttingen, Germany.]) Tmin = 0.857, Tmax = 1.000

  • 5308 measured reflections

  • 3688 independent reflections

  • 1992 reflections with I > 2σ(I)

  • Rint = 0.027

Refinement
  • R[F2 > 2σ(F2)] = 0.060

  • wR(F2) = 0.189

  • S = 1.03

  • 3688 reflections

  • 280 parameters

  • 2 restraints

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.51 e Å−3

  • Δρmin = −0.45 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N3—H3A⋯O1 0.86 2.01 2.735 (4) 141
N4—H4B⋯O1i 0.88 (2) 2.18 (2) 3.022 (5) 162 (4)
Symmetry code: (i) -x+1, -y+1, -z+1.

Data collection: SMART (Bruker, 2001[Bruker (2001). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2001[Bruker (2001). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL and local programs.

Supporting information


Comment top

Asymmetrical Schiff bases are of interest due to their catalytic activity and the selectivity of their transition metal complexes in various reactions. Several asymmetrical Schiff base ligands and their transition metal complexes have been synthesized and studied. Here we report the crystal structure of a novel asymmetrical Schiff base ligand (Fig. 1). Bond lengths of the compound are in the range of normal values (Allen et al., 1987) and are comparable to those observed in similar compounds (Lu et al., 2011). The molecules are linked by N—H···O hydrogen bonds and stacking interaction, as shown in Fig. 2. The distance between the centroids of adjacent rings (C18 to C23, x, y, z and -x + 2, -y + 1, -z + 1) is 3.862 (1) Å.

Related literature top

For related structures, see: Lu et al. (2011). For bond-length data, see: Allen et al. (1987). For the catalytic properties of asymmetric Schiff bases, see: Caboni et al. (2012). For the synthesis, see: Hennig & Mann (1988).

Experimental top

The title compound was obtained according to the synthetic procedure of Hennig & Mann (1988) with some modification. 1,2-diamino-4,5-dichlorobenzene and 4-benzoyl-3-methyl-1-phenyl-1H-pyrazol-5(4H)-one were refluxed for 2 h in a molar ratio of 1:1 in absolute ethanol to give the product. The single-crystal suitble for X-ray diffraction was obtained by slow evaporation of the ethanolic solution of the title compound.

Refinement top

H atoms of –NH2 group were located from a difference map and refined with a distance restraint of N—H = 0.87 (2) Å. Other H atoms were positioned geometrically and refined using a riding model with C—H = 0.95–0.99 Å, and with Uiso(H) = 1.2 (1.5 for methyl groups) times Ueq(C/N). The reflection -2 1 1 is a strong outlier and was omitted in the refinement.

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT (Bruker, 2001); 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 (Sheldrick, 2008) and local programs.

Figures top
[Figure 1] Fig. 1. The molecular structure of (I), with atom labels and 50% probability displacement ellipsoids for non-H atoms.
[Figure 2] Fig. 2. The packing of (I), showing molecules connected by hydrogen bonds (dashed lines) and stacking interaction. H atoms not involved in hydrogen bonding have been omitted.
(Z)-4-[(2-Amino-4,5-dichloroanilino)(phenyl)methylidene]-3-methyl-1- phenyl-1H-pyrazol-5(4H)-one top
Crystal data top
C23H18Cl2N4OZ = 2
Mr = 437.31F(000) = 452
Triclinic, P1Dx = 1.382 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 8.0653 (16) ÅCell parameters from 3250 reflections
b = 10.931 (2) Åθ = 1.8–25.2°
c = 13.851 (3) ŵ = 0.33 mm1
α = 111.627 (3)°T = 296 K
β = 90.775 (3)°Block, red
γ = 110.226 (3)°0.30 × 0.21 × 0.18 mm
V = 1051.1 (4) Å3
Data collection top
Bruker SMART 1K CCD area-detector
diffractometer
3688 independent reflections
Radiation source: fine-focus sealed tube1992 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.027
thin–slice ω scansθmax = 25.1°, θmin = 2.1°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2004)
h = 97
Tmin = 0.857, Tmax = 1.000k = 1312
5308 measured reflectionsl = 1516
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.060Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.189H atoms treated by a mixture of independent and constrained refinement
S = 1.03 w = 1/[σ2(Fo2) + (0.0881P)2]
where P = (Fo2 + 2Fc2)/3
3688 reflections(Δ/σ)max < 0.001
280 parametersΔρmax = 0.51 e Å3
2 restraintsΔρmin = 0.45 e Å3
Crystal data top
C23H18Cl2N4Oγ = 110.226 (3)°
Mr = 437.31V = 1051.1 (4) Å3
Triclinic, P1Z = 2
a = 8.0653 (16) ÅMo Kα radiation
b = 10.931 (2) ŵ = 0.33 mm1
c = 13.851 (3) ÅT = 296 K
α = 111.627 (3)°0.30 × 0.21 × 0.18 mm
β = 90.775 (3)°
Data collection top
Bruker SMART 1K CCD area-detector
diffractometer
3688 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2004)
1992 reflections with I > 2σ(I)
Tmin = 0.857, Tmax = 1.000Rint = 0.027
5308 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0602 restraints
wR(F2) = 0.189H atoms treated by a mixture of independent and constrained refinement
S = 1.03Δρmax = 0.51 e Å3
3688 reflectionsΔρmin = 0.45 e Å3
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
xyzUiso*/Ueq
Cl21.11130 (17)0.22914 (15)0.36132 (9)0.0878 (5)
Cl11.18254 (17)0.24718 (17)0.59173 (10)0.0939 (5)
O10.5427 (3)0.6431 (3)0.7490 (2)0.0541 (7)
N20.2712 (4)0.4857 (3)0.8999 (2)0.0573 (9)
N30.6743 (4)0.4320 (3)0.6750 (2)0.0498 (8)
H3A0.66120.50730.67590.060*
N10.3415 (4)0.5927 (3)0.8613 (2)0.0511 (8)
C190.9177 (5)0.3465 (4)0.6293 (3)0.0503 (10)
H19A0.94340.35790.69850.060*
C220.8476 (5)0.3187 (4)0.4243 (3)0.0502 (10)
H22A0.82660.31110.35580.060*
C180.7801 (5)0.3803 (4)0.6009 (3)0.0433 (9)
C90.3620 (5)0.4033 (4)0.8684 (3)0.0532 (10)
C60.2573 (5)0.6900 (4)0.8746 (3)0.0482 (9)
C230.7409 (5)0.3646 (4)0.4970 (3)0.0451 (9)
C110.5925 (5)0.3812 (4)0.7431 (3)0.0444 (9)
C70.4691 (5)0.5709 (4)0.8000 (3)0.0455 (9)
C201.0185 (5)0.2954 (4)0.5552 (3)0.0526 (10)
C120.6100 (5)0.2515 (4)0.7451 (3)0.0459 (9)
N40.6018 (5)0.3963 (4)0.4673 (3)0.0624 (10)
C80.4918 (5)0.4480 (4)0.8058 (3)0.0444 (9)
C210.9834 (5)0.2847 (4)0.4539 (3)0.0538 (10)
C130.7013 (5)0.2581 (4)0.8339 (3)0.0537 (10)
H13A0.74640.34280.89340.064*
C50.0782 (6)0.6554 (5)0.8833 (3)0.0607 (11)
H5A0.01070.56660.88250.073*
C10.3573 (6)0.8244 (4)0.8808 (3)0.0623 (11)
H1A0.47930.85040.87820.075*
C170.5389 (5)0.1236 (4)0.6589 (3)0.0625 (11)
H17A0.47430.11740.60000.075*
C150.6556 (7)0.0121 (5)0.7463 (4)0.0749 (14)
H15A0.67140.06830.74620.090*
C100.3125 (6)0.2748 (4)0.8947 (4)0.0731 (14)
H10A0.22100.27450.93830.110*
H10B0.41610.27750.93160.110*
H10C0.26870.19040.83100.110*
C40.0012 (6)0.7519 (6)0.8933 (3)0.0719 (13)
H4C0.12280.72680.89690.086*
C20.2773 (7)0.9199 (5)0.8910 (4)0.0775 (14)
H2B0.34451.00950.89320.093*
C140.7249 (6)0.1390 (5)0.8336 (4)0.0668 (12)
H14A0.78790.14410.89260.080*
C160.5628 (6)0.0062 (5)0.6596 (4)0.0753 (13)
H16A0.51570.07890.60060.090*
C30.0976 (8)0.8833 (6)0.8979 (4)0.0811 (15)
H3B0.04420.94860.90570.097*
H4A0.508 (4)0.381 (4)0.495 (3)0.062 (13)*
H4B0.572 (6)0.371 (5)0.3997 (17)0.092 (17)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl20.0813 (9)0.1355 (12)0.0620 (7)0.0711 (9)0.0337 (6)0.0267 (7)
Cl10.0773 (9)0.1571 (13)0.0793 (9)0.0818 (9)0.0190 (7)0.0461 (9)
O10.0631 (17)0.0617 (17)0.0604 (17)0.0372 (14)0.0316 (13)0.0354 (14)
N20.070 (2)0.059 (2)0.060 (2)0.0348 (19)0.0336 (17)0.0300 (17)
N30.062 (2)0.058 (2)0.0479 (19)0.0391 (17)0.0273 (16)0.0249 (16)
N10.057 (2)0.0536 (19)0.058 (2)0.0311 (17)0.0300 (16)0.0295 (16)
C190.053 (2)0.059 (2)0.043 (2)0.026 (2)0.0123 (18)0.0201 (19)
C220.048 (2)0.065 (3)0.041 (2)0.026 (2)0.0137 (18)0.0214 (19)
C180.044 (2)0.048 (2)0.046 (2)0.0230 (18)0.0170 (17)0.0215 (17)
C90.067 (3)0.056 (2)0.051 (2)0.032 (2)0.028 (2)0.027 (2)
C60.056 (3)0.056 (2)0.045 (2)0.035 (2)0.0187 (18)0.0200 (19)
C230.049 (2)0.048 (2)0.043 (2)0.0229 (19)0.0135 (17)0.0178 (18)
C110.046 (2)0.051 (2)0.040 (2)0.0218 (19)0.0120 (17)0.0200 (18)
C70.046 (2)0.051 (2)0.045 (2)0.0242 (19)0.0168 (18)0.0194 (18)
C200.046 (2)0.066 (3)0.051 (2)0.031 (2)0.0133 (19)0.020 (2)
C120.047 (2)0.046 (2)0.049 (2)0.0238 (19)0.0154 (18)0.0182 (19)
N40.060 (3)0.088 (3)0.067 (3)0.047 (2)0.021 (2)0.042 (2)
C80.057 (2)0.047 (2)0.042 (2)0.0327 (19)0.0211 (18)0.0192 (17)
C210.045 (2)0.064 (3)0.053 (2)0.025 (2)0.0189 (19)0.019 (2)
C130.067 (3)0.052 (2)0.047 (2)0.028 (2)0.012 (2)0.0184 (19)
C50.060 (3)0.065 (3)0.057 (3)0.030 (2)0.018 (2)0.018 (2)
C10.061 (3)0.065 (3)0.073 (3)0.034 (2)0.024 (2)0.031 (2)
C170.069 (3)0.058 (3)0.055 (3)0.025 (2)0.018 (2)0.016 (2)
C150.109 (4)0.071 (3)0.087 (4)0.064 (3)0.056 (3)0.046 (3)
C100.093 (4)0.066 (3)0.088 (3)0.043 (3)0.051 (3)0.048 (3)
C40.059 (3)0.098 (4)0.064 (3)0.047 (3)0.019 (2)0.021 (3)
C20.098 (4)0.076 (3)0.083 (3)0.054 (3)0.037 (3)0.037 (3)
C140.085 (3)0.078 (3)0.067 (3)0.053 (3)0.032 (2)0.039 (3)
C160.096 (4)0.048 (3)0.075 (3)0.029 (3)0.032 (3)0.015 (2)
C30.110 (4)0.103 (4)0.066 (3)0.080 (4)0.033 (3)0.035 (3)
Geometric parameters (Å, º) top
Cl2—C211.724 (4)C12—C171.380 (5)
Cl1—C201.716 (4)C12—C131.391 (5)
O1—C71.254 (4)N4—H4A0.850 (18)
N2—C91.309 (4)N4—H4B0.876 (19)
N2—N11.409 (4)C13—C141.378 (5)
N3—C111.336 (4)C13—H13A0.9300
N3—C181.424 (4)C5—C41.380 (5)
N3—H3A0.8600C5—H5A0.9300
N1—C71.372 (4)C1—C21.374 (5)
N1—C61.409 (4)C1—H1A0.9300
C19—C181.379 (5)C17—C161.365 (5)
C19—C201.394 (5)C17—H17A0.9300
C19—H19A0.9300C15—C161.375 (6)
C22—C211.374 (5)C15—C141.380 (6)
C22—C231.398 (5)C15—H15A0.9300
C22—H22A0.9300C10—H10A0.9600
C18—C231.404 (5)C10—H10B0.9600
C9—C81.439 (5)C10—H10C0.9600
C9—C101.502 (5)C4—C31.357 (7)
C6—C11.379 (5)C4—H4C0.9300
C6—C51.380 (5)C2—C31.378 (7)
C23—N41.381 (5)C2—H2B0.9300
C11—C81.382 (5)C14—H14A0.9300
C11—C121.482 (5)C16—H16A0.9300
C7—C81.448 (5)C3—H3B0.9300
C20—C211.380 (5)
C9—N2—N1105.9 (3)C11—C8—C7122.6 (3)
C11—N3—C18129.7 (3)C9—C8—C7104.5 (3)
C11—N3—H3A115.2C22—C21—C20121.3 (3)
C18—N3—H3A115.2C22—C21—Cl2118.2 (3)
C7—N1—C6128.5 (3)C20—C21—Cl2120.5 (3)
C7—N1—N2112.0 (3)C14—C13—C12119.9 (4)
C6—N1—N2118.6 (3)C14—C13—H13A120.1
C18—C19—C20120.5 (3)C12—C13—H13A120.1
C18—C19—H19A119.7C6—C5—C4120.3 (4)
C20—C19—H19A119.7C6—C5—H5A119.8
C21—C22—C23120.2 (3)C4—C5—H5A119.8
C21—C22—H22A119.9C2—C1—C6120.1 (4)
C23—C22—H22A119.9C2—C1—H1A119.9
C19—C18—C23120.3 (3)C6—C1—H1A119.9
C19—C18—N3121.7 (3)C16—C17—C12120.4 (4)
C23—C18—N3118.0 (3)C16—C17—H17A119.8
N2—C9—C8112.2 (3)C12—C17—H17A119.8
N2—C9—C10118.4 (3)C16—C15—C14119.1 (4)
C8—C9—C10129.3 (3)C16—C15—H15A120.4
C1—C6—C5119.1 (4)C14—C15—H15A120.4
C1—C6—N1119.1 (4)C9—C10—H10A109.5
C5—C6—N1121.8 (4)C9—C10—H10B109.5
N4—C23—C22120.6 (3)H10A—C10—H10B109.5
N4—C23—C18120.7 (3)C9—C10—H10C109.5
C22—C23—C18118.6 (3)H10A—C10—H10C109.5
N3—C11—C8119.3 (3)H10B—C10—H10C109.5
N3—C11—C12117.7 (3)C3—C4—C5120.2 (4)
C8—C11—C12123.0 (3)C3—C4—H4C119.9
O1—C7—N1125.3 (3)C5—C4—H4C119.9
O1—C7—C8129.5 (3)C1—C2—C3120.2 (5)
N1—C7—C8105.2 (3)C1—C2—H2B119.9
C21—C20—C19119.0 (3)C3—C2—H2B119.9
C21—C20—Cl1121.7 (3)C13—C14—C15120.5 (4)
C19—C20—Cl1119.3 (3)C13—C14—H14A119.8
C17—C12—C13119.1 (3)C15—C14—H14A119.8
C17—C12—C11120.8 (3)C17—C16—C15120.9 (4)
C13—C12—C11120.0 (3)C17—C16—H16A119.5
C23—N4—H4A120 (3)C15—C16—H16A119.5
C23—N4—H4B117 (3)C4—C3—C2120.0 (4)
H4A—N4—H4B110 (4)C4—C3—H3B120.0
C11—C8—C9131.6 (3)C2—C3—H3B120.0
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3A···O10.862.012.735 (4)141
N4—H4B···O1i0.88 (2)2.18 (2)3.022 (5)162 (4)
Symmetry code: (i) x+1, y+1, z+1.

Experimental details

Crystal data
Chemical formulaC23H18Cl2N4O
Mr437.31
Crystal system, space groupTriclinic, P1
Temperature (K)296
a, b, c (Å)8.0653 (16), 10.931 (2), 13.851 (3)
α, β, γ (°)111.627 (3), 90.775 (3), 110.226 (3)
V3)1051.1 (4)
Z2
Radiation typeMo Kα
µ (mm1)0.33
Crystal size (mm)0.30 × 0.21 × 0.18
Data collection
DiffractometerBruker SMART 1K CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2004)
Tmin, Tmax0.857, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
5308, 3688, 1992
Rint0.027
(sin θ/λ)max1)0.597
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.060, 0.189, 1.03
No. of reflections3688
No. of parameters280
No. of restraints2
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.51, 0.45

Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008) and local programs.

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3A···O10.862.012.735 (4)141.3
N4—H4B···O1i0.876 (19)2.18 (2)3.022 (5)162 (4)
Symmetry code: (i) x+1, y+1, z+1.
 

Acknowledgements

The project was supported by the National Natural Science Foundation of China (program Nos. 21103135 and 21073139), the Natural Science Basic Research Plan in Shaanxi Province of China (program No. 2011JQ2011) and the Scientific Research Program Funded by Shaanxi Provincial Education Department (program No.12 J K0622).

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