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Acta Crystallogr Sect E Struct Rep Online. 2010 July 1; 66(Pt 7): o1654.
Published online 2010 June 16. doi:  10.1107/S1600536810021835
PMCID: PMC3007078

(2E)-2-[2-(4-Chloro­phen­yl)hydrazin-1-yl­idene]-4,4,4-trifluoro-3-oxobutanal

Abstract

The title compound, C10H6ClF3N2O2, was synthesized by coupling 4-dimethyl­amino-1,1,1-trifluoro­but-3-en-2-one with 4-chloro­benzene­diazo­nium chloride. It crystallizes with two mol­ecules in the asymmetric unit, which form two similar centrosymmetric dimers via hydrogen bonds. Extensive electron delocalization and intra­molecular N—H(...)O hydrogen bonds are responsible for a planar conformation of the mol­ecules (maximum deviations = 0.010 and −0.015 Å for the two molecules). In addition to hydrogen bonds, π–π stacking inter­actions with centroid–centroid distances of 3.604 (2) and 3.583 (2) Å contribute to the stability of the crystal structure.

Related literature

For the crystal structure of the isostructural iodo derivative, see: Jiang & Zhu (2008 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-o1654-scheme1.jpg

Experimental

Crystal data

  • C10H6ClF3N2O2
  • M r = 278.62
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o1654-efi1.jpg
  • a = 7.6440 (4) Å
  • b = 7.7139 (4) Å
  • c = 19.4221 (10) Å
  • α = 86.134 (1)°
  • β = 81.706 (1)°
  • γ = 88.999 (1)°
  • V = 1130.63 (10) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.37 mm−1
  • T = 173 K
  • 0.44 × 0.38 × 0.35 mm

Data collection

  • Bruker SMART 1000 CCD diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2001 [triangle]) T min = 0.853, T max = 0.880
  • 8820 measured reflections
  • 4387 independent reflections
  • 3577 reflections with I > 2σ(I)
  • R int = 0.017

Refinement

  • R[F 2 > 2σ(F 2)] = 0.033
  • wR(F 2) = 0.111
  • S = 1.05
  • 4387 reflections
  • 325 parameters
  • H-atom parameters constrained
  • Δρmax = 0.29 e Å−3
  • Δρmin = −0.23 e Å−3

Data collection: SMART (Bruker, 2001 [triangle]); cell refinement: SAINT-Plus (Bruker, 2003 [triangle]); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 [triangle]); software used to prepare material for publication: SHELXL97.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810021835/gk2268sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810021835/gk2268Isup2.hkl

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

Acknowledgments

This work was supported by the National Natural Science Foundation of China (No. 20802010), the Natural Science Foundation of Guangdong Province (No.07300884) and the 211 project of Guangdong Province.

supplementary crystallographic information

Comment

Herein, we report the crystal structure of (2E)-2-[2-(4-chlorophenyl)]hydrazinylidene]-4,4,4-trifluoro-3-oxobutanal, which was prepared via a reaction of 4-(dimethylamino)-1,1,1-trifluorobut-3-en-2-one with diazonium salt according to the procedure reported by Zhu et al. (2008). The title compound, 3, has been characterized by ESI-MS, NMR, FTIR spectroscopy and elemental analysis. Here we report the crystal structure of 3. It crystallizes with two almost identical molecules in the asymmetric unit. The molecule is almost planar except for the –CF3 group F atoms. There are some supramolecular interactions in the compound 3. The intramolecular N—H···O hydrogen bonds are N11—H11···O8 and N29—H29···O26 (Table 1) together with strong π-π stacking interactions [centroid-to-centroid distance = 3.604 (2) Å; 3.583 (2) Å] that contribute to the stability of the structure.

Experimental

The title compound was prepared via the reaction of 4-(dimethylamino)-1,1,1-trifluorobut-3-en-2-one with diazonium salt according to the procedure reported by Zhu et al. (2008). A solution of the p-chloroaniline 2 (1.28 g, 10 mmol) in a solution of 3 M HCl (5 ml) was diazotized at 0 °C by slow addition of a solution of NaNO2 (0.7 g, 10 mmol) in 5 ml H2O. The solution of aniline diazonium salt was added dropwise to a mixture of compound 1 (see scheme) (1.67 g, 10 mmol) with NaOH (1.6 g, 40 mmol) and ethanol (50 ml) in ice-salt bath. The reaction mixture was stirred for 1 h at the same temperature, then TLC analysis showed that the reaction had finished. The resulting precipitate was filtered off. Purification by column chromatography on silica gel (hexane:AcOEt = 30:1) gave red solid 3 in 75% yield. mp 418-420 K. 1H NMR (CDCl3, 300 MHz) δ14.87 (1H, s, NH), 10.03 (1H, s, CHO), 7.45 (4H, s, Ph), 19F NMR (CDCl3): -71.50 (3 F, s, CF3). IR (KBr, cm-1): 2924, 1699, 1526, 1308, 1187, 1157, 897; ESI-MS m/z: 279.9 ([M+H]+); Elemental analysis: found C: 43.13, H: 2.29, N: 10.07; calculated for (C10H6ClF3N2O2) C: 43.11 H: 2.17 N: 10.05 (%). 20 mg of compound 3 was dissolved in 10 ml (EtOAc:pPetroleum ether = 1:8) and the solution was kept at room temperature for 6 d, natural evaporation gave red single crystals of compound 3 suitable for X-ray analysis.

Refinement

All H atoms were positioned geometrically and refined using a riding model, with all C—H = 0.95 Å, N—H = 0.88 Å and with Uĩso(H) = 1.2Ueq(C), Uĩso(H) = 1.2Ueq(N).

Figures

Fig. 1.
The synthesis of (E)-2-(2-(4-Chlophenyl)hydrazono)-4,4,4-trifluoro-3-oxobutanal
Fig. 2.
View of the asymmetric unit in the title compound.

Crystal data

C10H6ClF3N2O2Z = 4
Mr = 278.62F(000) = 560
Triclinic, P1Dx = 1.637 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.6440 (4) ÅCell parameters from 8820 reflections
b = 7.7139 (4) Åθ = 1.1–26.0°
c = 19.4221 (10) ŵ = 0.37 mm1
α = 86.134 (1)°T = 173 K
β = 81.706 (1)°Block, yellow
γ = 88.999 (1)°0.44 × 0.38 × 0.35 mm
V = 1130.63 (10) Å3

Data collection

Bruker SMART 1000 CCD diffractometer4387 independent reflections
Radiation source: fine-focus sealed tube3577 reflections with I > 2σ(I)
graphiteRint = 0.017
ω scansθmax = 26.0°, θmin = 1.1°
Absorption correction: multi-scan (SADABS; Bruker, 2001)h = −9→9
Tmin = 0.853, Tmax = 0.880k = −9→9
8820 measured reflectionsl = −23→23

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.033Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.111H-atom parameters constrained
S = 1.05w = 1/[σ2(Fo2) + (0.0688P)2 + 0.2643P] where P = (Fo2 + 2Fc2)/3
4387 reflections(Δ/σ)max = 0.001
325 parametersΔρmax = 0.29 e Å3
0 restraintsΔρmin = −0.23 e Å3

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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)

xyzUiso*/Ueq
F10.41928 (17)−0.14617 (18)0.81983 (6)0.0571 (4)
F20.43024 (15)0.08932 (15)0.75482 (6)0.0461 (3)
F30.36230 (15)−0.15031 (16)0.71485 (6)0.0464 (3)
C40.4666 (3)−0.0800 (3)0.75480 (10)0.0373 (4)
C50.6660 (2)−0.1153 (2)0.73104 (9)0.0312 (4)
O60.7481 (2)−0.19276 (19)0.77259 (7)0.0478 (4)
C70.7407 (2)−0.0528 (2)0.66091 (9)0.0271 (4)
O80.99555 (16)−0.04137 (17)0.57727 (7)0.0362 (3)
C90.9266 (2)−0.0873 (2)0.63594 (10)0.0315 (4)
H90.9963−0.14780.66660.038*
N100.62895 (18)0.03374 (17)0.62508 (7)0.0258 (3)
N110.67864 (18)0.09586 (17)0.56194 (7)0.0255 (3)
H110.78790.08040.54170.031*
C120.5552 (2)0.18901 (19)0.52582 (8)0.0244 (3)
C130.3785 (2)0.2002 (2)0.55450 (9)0.0287 (4)
H130.33840.14590.59920.034*
C140.2614 (2)0.2914 (2)0.51727 (10)0.0316 (4)
H140.13980.29890.53590.038*
C150.3231 (2)0.3710 (2)0.45304 (9)0.0290 (4)
Cl160.17686 (7)0.48727 (6)0.40584 (3)0.04196 (15)
C170.4984 (2)0.3604 (2)0.42417 (9)0.0296 (4)
H170.53820.41580.37960.036*
C180.6156 (2)0.2678 (2)0.46094 (9)0.0287 (4)
H180.73670.25850.44170.034*
F190.14628 (17)0.47780 (18)0.67586 (6)0.0541 (3)
F200.32094 (14)0.45871 (15)0.75272 (6)0.0422 (3)
F210.06433 (17)0.57720 (15)0.77605 (7)0.0525 (3)
C220.1519 (2)0.4478 (3)0.74380 (10)0.0368 (4)
C230.0728 (2)0.2668 (2)0.76964 (10)0.0344 (4)
O240.0173 (2)0.1827 (2)0.72714 (8)0.0522 (4)
C250.0720 (2)0.2110 (2)0.84266 (9)0.0302 (4)
O260.0099 (2)−0.01845 (17)0.92755 (7)0.0438 (3)
C270.0109 (2)0.0371 (2)0.86723 (10)0.0367 (4)
H27−0.0294−0.03550.83530.044*
N280.13267 (18)0.32559 (19)0.88092 (7)0.0287 (3)
N290.13874 (19)0.29289 (19)0.94648 (7)0.0295 (3)
H290.10230.19240.96730.035*
C300.2050 (2)0.4213 (2)0.98458 (9)0.0287 (4)
C310.2464 (2)0.5856 (2)0.95348 (10)0.0346 (4)
H310.23050.61320.90640.042*
C320.3108 (3)0.7084 (3)0.99149 (11)0.0391 (4)
H320.34000.82120.97070.047*
C330.3327 (2)0.6661 (3)1.06009 (10)0.0367 (4)
Cl340.41607 (7)0.82172 (8)1.10737 (3)0.05462 (18)
C350.2909 (3)0.5042 (3)1.09141 (10)0.0397 (4)
H350.30580.47731.13870.048*
C360.2265 (2)0.3804 (3)1.05305 (10)0.0355 (4)
H360.19740.26771.07390.043*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
F10.0558 (8)0.0763 (9)0.0332 (7)−0.0031 (7)0.0083 (6)0.0094 (6)
F20.0472 (7)0.0443 (7)0.0457 (7)0.0121 (5)−0.0005 (5)−0.0122 (5)
F30.0399 (6)0.0555 (7)0.0441 (7)−0.0124 (5)−0.0044 (5)−0.0055 (5)
C40.0405 (11)0.0413 (10)0.0281 (9)−0.0002 (8)0.0008 (8)−0.0012 (8)
C50.0361 (9)0.0271 (8)0.0306 (9)0.0005 (7)−0.0056 (8)−0.0019 (7)
O60.0513 (9)0.0526 (9)0.0378 (8)0.0088 (7)−0.0084 (7)0.0115 (7)
C70.0293 (8)0.0254 (8)0.0274 (9)0.0005 (7)−0.0058 (7)−0.0031 (6)
O80.0294 (7)0.0437 (7)0.0344 (7)0.0009 (6)−0.0017 (5)−0.0011 (6)
C90.0299 (9)0.0311 (9)0.0344 (10)0.0017 (7)−0.0068 (8)−0.0031 (7)
N100.0293 (7)0.0225 (7)0.0262 (7)−0.0011 (6)−0.0056 (6)−0.0028 (5)
N110.0238 (7)0.0257 (7)0.0267 (7)−0.0001 (5)−0.0031 (6)−0.0007 (6)
C120.0289 (8)0.0188 (7)0.0266 (8)0.0002 (6)−0.0071 (7)−0.0035 (6)
C130.0307 (9)0.0256 (8)0.0290 (9)−0.0008 (7)−0.0018 (7)−0.0008 (7)
C140.0269 (9)0.0285 (9)0.0398 (10)0.0013 (7)−0.0044 (7)−0.0050 (7)
C150.0344 (9)0.0235 (8)0.0318 (9)0.0047 (7)−0.0129 (7)−0.0052 (7)
Cl160.0452 (3)0.0363 (3)0.0482 (3)0.0099 (2)−0.0215 (2)−0.0017 (2)
C170.0369 (9)0.0266 (8)0.0255 (9)0.0000 (7)−0.0056 (7)−0.0012 (7)
C180.0282 (8)0.0281 (8)0.0294 (9)0.0005 (7)−0.0020 (7)−0.0028 (7)
F190.0567 (8)0.0720 (9)0.0322 (6)−0.0073 (6)−0.0087 (5)0.0149 (6)
F200.0355 (6)0.0476 (6)0.0424 (6)−0.0043 (5)−0.0058 (5)0.0071 (5)
F210.0563 (8)0.0395 (6)0.0557 (8)0.0145 (6)0.0049 (6)0.0082 (6)
C220.0339 (10)0.0426 (11)0.0326 (10)0.0036 (8)−0.0030 (8)0.0024 (8)
C230.0291 (9)0.0417 (10)0.0321 (10)0.0027 (8)−0.0039 (7)−0.0026 (8)
O240.0641 (10)0.0588 (9)0.0367 (8)−0.0119 (8)−0.0154 (7)−0.0049 (7)
C250.0281 (9)0.0313 (9)0.0302 (9)0.0021 (7)−0.0015 (7)−0.0020 (7)
O260.0559 (9)0.0368 (7)0.0379 (8)−0.0070 (6)−0.0066 (6)0.0050 (6)
C270.0389 (10)0.0337 (10)0.0374 (11)−0.0014 (8)−0.0037 (8)−0.0041 (8)
N280.0245 (7)0.0328 (8)0.0277 (8)0.0039 (6)−0.0008 (6)−0.0002 (6)
N290.0295 (7)0.0310 (8)0.0268 (8)−0.0002 (6)−0.0011 (6)0.0006 (6)
C300.0215 (8)0.0346 (9)0.0291 (9)0.0017 (7)−0.0002 (7)−0.0030 (7)
C310.0340 (9)0.0383 (10)0.0303 (9)−0.0017 (8)−0.0014 (8)0.0003 (8)
C320.0363 (10)0.0373 (10)0.0424 (11)−0.0042 (8)−0.0012 (8)−0.0028 (8)
C330.0253 (9)0.0460 (11)0.0396 (11)−0.0003 (8)−0.0028 (8)−0.0137 (8)
Cl340.0433 (3)0.0645 (4)0.0607 (4)−0.0052 (3)−0.0112 (3)−0.0283 (3)
C350.0346 (10)0.0545 (12)0.0308 (10)0.0021 (9)−0.0076 (8)−0.0049 (9)
C360.0354 (10)0.0397 (10)0.0307 (10)0.0005 (8)−0.0051 (8)0.0023 (8)

Geometric parameters (Å, °)

F1—C41.332 (2)F19—C221.331 (2)
F2—C41.331 (2)F20—C221.333 (2)
F3—C41.335 (2)F21—C221.333 (2)
C4—C51.553 (3)C22—C231.553 (3)
C5—O61.213 (2)C23—O241.210 (2)
C5—C71.453 (2)C23—C251.453 (3)
C7—N101.322 (2)C25—N281.324 (2)
C7—C91.459 (2)C25—C271.455 (2)
O8—C91.217 (2)O26—C271.219 (2)
C9—H90.9500C27—H270.9500
N10—N111.2924 (19)N28—N291.289 (2)
N11—C121.414 (2)N29—C301.418 (2)
N11—H110.8800N29—H290.8800
C12—C181.382 (2)C30—C361.378 (3)
C12—C131.388 (2)C30—C311.388 (3)
C13—C141.384 (2)C31—C321.378 (3)
C13—H130.9500C31—H310.9500
C14—C151.376 (3)C32—C331.383 (3)
C14—H140.9500C32—H320.9500
C15—C171.380 (3)C33—C351.374 (3)
C15—Cl161.7444 (17)C33—Cl341.7418 (19)
C17—C181.384 (2)C35—C361.388 (3)
C17—H170.9500C35—H350.9500
C18—H180.9500C36—H360.9500
F2—C4—F1106.75 (15)F19—C22—F20106.75 (15)
F2—C4—F3107.72 (16)F19—C22—F21107.22 (15)
F1—C4—F3107.31 (15)F20—C22—F21107.53 (16)
F2—C4—C5111.72 (15)F19—C22—C23110.29 (16)
F1—C4—C5110.14 (16)F20—C22—C23112.13 (15)
F3—C4—C5112.91 (15)F21—C22—C23112.62 (15)
O6—C5—C7124.78 (17)O24—C23—C25124.99 (18)
O6—C5—C4117.46 (17)O24—C23—C22117.30 (17)
C7—C5—C4117.76 (15)C25—C23—C22117.70 (16)
N10—C7—C5114.86 (15)N28—C25—C23115.36 (16)
N10—C7—C9125.69 (16)N28—C25—C27125.67 (17)
C5—C7—C9119.46 (15)C23—C25—C27118.95 (16)
O8—C9—C7122.43 (16)O26—C27—C25122.08 (18)
O8—C9—H9118.8O26—C27—H27119.0
C7—C9—H9118.8C25—C27—H27119.0
N11—N10—C7121.04 (14)N29—N28—C25121.73 (15)
N10—N11—C12119.13 (14)N28—N29—C30118.97 (14)
N10—N11—H11120.4N28—N29—H29120.5
C12—N11—H11120.4C30—N29—H29120.5
C18—C12—C13121.04 (15)C36—C30—C31120.69 (17)
C18—C12—N11117.95 (15)C36—C30—N29118.84 (16)
C13—C12—N11121.01 (15)C31—C30—N29120.47 (16)
C14—C13—C12119.29 (16)C32—C31—C30119.47 (18)
C14—C13—H13120.4C32—C31—H31120.3
C12—C13—H13120.4C30—C31—H31120.3
C15—C14—C13119.29 (16)C31—C32—C33119.50 (18)
C15—C14—H14120.4C31—C32—H32120.2
C13—C14—H14120.4C33—C32—H32120.2
C14—C15—C17121.74 (16)C35—C33—C32121.38 (18)
C14—C15—Cl16119.69 (14)C35—C33—Cl34119.53 (16)
C17—C15—Cl16118.57 (14)C32—C33—Cl34119.09 (16)
C15—C17—C18119.14 (16)C33—C35—C36119.10 (18)
C15—C17—H17120.4C33—C35—H35120.4
C18—C17—H17120.4C36—C35—H35120.4
C12—C18—C17119.49 (16)C30—C36—C35119.85 (18)
C12—C18—H18120.3C30—C36—H36120.1
C17—C18—H18120.3C35—C36—H36120.1
F2—C4—C5—O6117.94 (19)F19—C22—C23—O24−0.9 (2)
F1—C4—C5—O6−0.5 (2)F20—C22—C23—O24−119.74 (19)
F3—C4—C5—O6−120.46 (19)F21—C22—C23—O24118.8 (2)
F2—C4—C5—C7−61.9 (2)F19—C22—C23—C25178.66 (15)
F1—C4—C5—C7179.66 (15)F20—C22—C23—C2559.8 (2)
F3—C4—C5—C759.7 (2)F21—C22—C23—C25−61.6 (2)
O6—C5—C7—N10−177.83 (17)O24—C23—C25—N28−177.47 (18)
C4—C5—C7—N102.0 (2)C22—C23—C25—N283.0 (2)
O6—C5—C7—C91.8 (3)O24—C23—C25—C274.1 (3)
C4—C5—C7—C9−178.39 (15)C22—C23—C25—C27−175.47 (16)
N10—C7—C9—O8−2.0 (3)N28—C25—C27—O260.5 (3)
C5—C7—C9—O8178.45 (16)C23—C25—C27—O26178.74 (17)
C5—C7—N10—N11−179.81 (14)C23—C25—N28—N29179.78 (15)
C9—C7—N10—N110.6 (2)C27—C25—N28—N29−1.9 (3)
C7—N10—N11—C12−179.37 (14)C25—N28—N29—C30−179.92 (14)
N10—N11—C12—C18174.08 (14)N28—N29—C30—C36−174.13 (15)
N10—N11—C12—C13−6.2 (2)N28—N29—C30—C316.3 (2)
C18—C12—C13—C140.2 (2)C36—C30—C31—C320.5 (3)
N11—C12—C13—C14−179.47 (15)N29—C30—C31—C32−179.94 (16)
C12—C13—C14—C15−0.9 (2)C30—C31—C32—C33−0.2 (3)
C13—C14—C15—C171.0 (3)C31—C32—C33—C35−0.3 (3)
C13—C14—C15—Cl16−179.66 (13)C31—C32—C33—Cl34179.43 (14)
C14—C15—C17—C18−0.3 (3)C32—C33—C35—C360.5 (3)
Cl16—C15—C17—C18−179.69 (13)Cl34—C33—C35—C36−179.23 (14)
C13—C12—C18—C170.4 (2)C31—C30—C36—C35−0.3 (3)
N11—C12—C18—C17−179.87 (14)N29—C30—C36—C35−179.87 (15)
C15—C17—C18—C12−0.4 (2)C33—C35—C36—C30−0.2 (3)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N11—H11···O80.882.012.6746 (18)131
N29—H29···O260.882.032.679 (2)130
N29—H29···O26i0.882.423.2159 (19)150
C27—H27···O6ii0.952.593.491 (2)158
C36—H36···O26i0.952.523.323 (3)143

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: GK2268).

References

  • Bruker (2001). SAINT-Plus and SADABS Bruker AXS Inc., Madison, Wisconsin, USA.
  • Bruker (2003). SMART Bruker AXS Inc., Madison, Wisconsin, USA.
  • Farrugia, L. J. (1997). J. Appl. Cryst.30, 565.
  • Jiang, H. & Zhu, S. (2008). J. Fluorine Chem.129, 40–44.
  • Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. [PubMed]

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