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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 4| April 2011| Page o859
doi:10.1107/S1600536811005022

(Z)-N′-Hy­dr­oxy-4-(tri­fluoro­meth­yl)benzimidamide

Fei Liu,a* Fang Zhang,a Qifan Chenb and Mingdong Dongb

aCollege of Chemical Engineering & Materials, Eastern Liaoning University, No. 325 Wenhua Road, Yuanbao District, Dandong City, Liaoning Province 118003, People's Republic of China, and bExperiment Center, Eastern Liaoning University, No. 325 Wenhua Road, Yuanbao District, Dandong City, Liaoning Province 118003, People's Republic of China
*Correspondence e-mail: berylliu8090@sina.com

(Received 10 February 2011; accepted 10 February 2011; online 12 March 2011)

In the title compound, C8H7F3N2O, the OH and NH2 substituents adopt a Z configuration with respect to the C=N bond. The hy­droxy­imidamide unit is almost planar (r.m.s. deviation = 0.007 Å) and subtends an angle of 26.25 (13)° with the benzene ring. The F atoms of the trifluoro­methyl substituent are disordered over two sets of sites with an occupancy ratio of 0.783 (15):0.217 (15). In the crystal, O—H⋯N hydrogen bonds form centrosymmetric dimers. Additional N—H⋯O hydrogen bonds link the dimers into zigzag chains along the b axis. Weak inter­molecular F⋯F contacts of 2.714 (5) Å are also observed.

Related literature

For the preparation of the title compound, see: Rai et al. (2010[Rai, N. P., Narayanaswamy, V. K., Govender, T., Manuprasad, B. K., Shashikanth, S. & Arunachalam, P. N. (2010). Eur. J. Med. Chem. 45, 2677-2682.]). For the use of oxime derivatives in crystal engineering, see: Aakeröy et al. (2000[Aakeröy, C. B., Beatty, A. M. & Leinen, D. S. (2000). CrystEngComm, 2, 145-150.]). For a related structure, see: Orama & Saarinen (1996[Orama, M. & Saarinen, H. (1996). Acta Chem. Scand. 50, 1087-1091.]).

[Scheme 1]

Experimental

Crystal data

  • C8H7F3N2O

  • Mr = 204.16

  • Monoclinic, P 21 /c

  • a = 9.8706 (8) Å

  • b = 11.2540 (12) Å

  • c = 8.4033 (7) Å

  • β = 104.61 (2)°

  • V = 903.29 (16) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.14 mm−1

  • T = 293 K

  • 0.32 × 0.24 × 0.20 mm
Data collection

  • Rigaku R-AXIS RAPID diffractometer

  • Absorption correction: multi-scan (ABSCOR; Higashi, 1995[Higashi, T. (1995). ABSCOR. Rigaku Corporation, Tokyo, Japan.]) Tmin = 0.946, Tmax = 0.972

  • 8605 measured reflections

  • 2058 independent reflections

  • 1324 reflections with I > 2σ(I)

  • Rint = 0.077
Refinement

  • R[F2 > 2σ(F2)] = 0.056

  • wR(F2) = 0.183

  • S = 1.07

  • 2058 reflections

  • 164 parameters

  • 42 restraints

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

  • Δρmax = 0.23 e Å−3

  • Δρmin = −0.29 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
N1—H1N⋯O1i 0.84 (3) 2.36 (3) 3.165 (3) 161 (3)
O1—H1O⋯N2ii 0.86 (3) 1.98 (3) 2.766 (2) 152 (3)
Symmetry codes: (i) [x, -y+{\script{3\over 2}}, z-{\script{1\over 2}}]; (ii) -x+1, -y+1, -z+2.

Data collection: PROCESS-AUTO (Rigaku, 2006[Rigaku (2006). PROCESS-AUTO. Rigaku Corporation, Tokyo, Japan.]); cell refinement: PROCESS-AUTO; data reduction: CrystalStructure (Rigaku, 2007[Rigaku (2007). CrystalStructure. Rigaku Corporation, Tokyo, Japan, and Rigaku Americas, The Woodlands, Texas, USA.]); 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: ORTEP-3 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811005022/sj5105sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811005022/sj5105Isup2.hkl

checkCIF report


Comment top

The oxime functionality is well known in organic synthesis, analytical chemistry, and coordination chemistry, yet it has remained relatively unexplored as an intermolecular connector in crystal engineering (Aakeröy et al., 2000).

In the title compound, the oxime also carries an amine substituent and assumes a Z configuration with respect to the C8═N2 bond (Fig. 1). Atoms F1A:F3B, F2A:F1B, F3A: F2B are disordered over two positions and with site occupancies of 0.5:0.5. The C8,N1,N2,O1 hydroxyimidamide unit is almost planar (r.m.s. deviation 0.007 Å) and subtends an angle of 26.25 (13)° to the C2···C7 benzene ring. The torsion angle O1—N2—C8—C5 between the oxime unit and the ring system is -177.71 (15)°. In the crystal O1–H1O···N1 hydrogen bonds form centrosymmetric dimers. An additional N1–H1N···O1 hydrogen bond links these dimers into zigzag chains along b. Weak intermolecular F2A···F2Aiii contacts, 2.714 (5) Å, (iii = -x, 1-y, -z) are also observed (Fig. 2).

Related literature top

For the preparation of the title compound, see: Rai et al. (2010). For the use of oxime derivatives in crystal engineering, see: Aakeröy et al. (2000). For a related structure, see: Orama & Saarinen (1996).

Experimental top

The compound was prepared by a reported procedure (Rai et al., 2010) To a solution of 4-(trifluoromethyl)benzonitrile (0.2 mol) in ethanol (20 mL) was added hydroxylamine hydrochloride (0.4 mol) in water (40 mL). Then anhydrous sodium carbonate(0.4 mol) in water (120 mL) was slowly added to the resulting solution and the mixture was stirred at 358k for 5 h and then concentrated under vacuum to evaporate some water. The resulting suspension was filtered, the solid that formed was washed with cold water and dried under vacuum. Block-shaped crystals suitable for X-ray diffraction were obtained from methanol.

Refinement top

H atoms bound to N and O were located in difference Fourier maps and refined isotropically with Uiso(H) = 1.2Ueq(N) [1.5Ueq(O)]. H atoms attached to C were added at their calculated positions and included in the structure factor calculations, with C—H = 0.93Å (aromatic) and 0.97 Å (methylene), and with Uiso(H) = 1.2Ueq(C). The F atoms of the CF3 group were disordered over two positions. Occupancy was fixed at 0.5 for each component in the final refinement cycles.

Computing details top

Data collection: PROCESS-AUTO (Rigaku, 2006); cell refinement: PROCESS-AUTO (Rigaku, 2006); data reduction: CrystalStructure (Rigaku, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. Structure of the title compound with 50% probability displacement ellipsoids. For clarity, only one of the two equivalent disorder components is shown.
[Figure 2] Fig. 2. Crystal packing of the title compound viewed down the c axis. Hydrogen bonds and F···F contacts are drawn as dashed lines.
N'-hydroxy-4-(trifluoromethyl)benzene-1-carboximidamide top
Crystal data top
C8H7F3N2OF(000) = 416
Mr = 204.16Dx = 1.501 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 4741 reflections
a = 9.8706 (8) Åθ = 3.1–27.4°
b = 11.2540 (12) ŵ = 0.14 mm−1
c = 8.4033 (7) ÅT = 293 K
β = 104.61 (2)°Irregular block, colorless
V = 903.29 (16) Å30.32 × 0.24 × 0.20 mm
Z = 4
Data collection top
Rigaku R-AXIS RAPID
diffractometer		2058 independent reflections
Radiation source: fine-focus sealed tube1324 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.077
Detector resolution: 10.0 pixels mm-1θmax = 27.4°, θmin = 3.1°
ω scansh = −12→12
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)		k = −14→14
Tmin = 0.946, Tmax = 0.972l = −10→10
8605 measured reflections
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)] = 0.056Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.183H atoms treated by a mixture of independent and constrained refinement
S = 1.07 w = 1/[σ2(Fo2) + (0.101P)2 + 0.058P]
where P = (Fo2 + 2Fc2)/3
2058 reflections(Δ/σ)max < 0.001
164 parametersΔρmax = 0.23 e Å−3
42 restraintsΔρmin = −0.29 e Å−3
Crystal data top
C8H7F3N2OV = 903.29 (16) Å3
Mr = 204.16Z = 4
Monoclinic, P21/cMo Kα radiation
a = 9.8706 (8) ŵ = 0.14 mm−1
b = 11.2540 (12) ÅT = 293 K
c = 8.4033 (7) Å0.32 × 0.24 × 0.20 mm
β = 104.61 (2)°
Data collection top
Rigaku R-AXIS RAPID
diffractometer		2058 independent reflections
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)		1324 reflections with I > 2σ(I)
Tmin = 0.946, Tmax = 0.972Rint = 0.077
8605 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.05642 restraints
wR(F2) = 0.183H atoms treated by a mixture of independent and constrained refinement
S = 1.07Δρmax = 0.23 e Å−3
2058 reflectionsΔρmin = −0.29 e Å−3
164 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*/UeqOcc. (<1)
C1−0.0030 (2)0.6553 (2)0.2394 (3)0.0759 (7)
F1A−0.0355 (6)0.7584 (3)0.1633 (6)0.1154 (16)0.783 (15)
F2A−0.0071 (5)0.5782 (6)0.1205 (6)0.1246 (19)0.783 (15)
F3A−0.1063 (3)0.6322 (8)0.3082 (5)0.1140 (18)0.783 (15)
F2B−0.082 (2)0.564 (2)0.260 (3)0.133 (8)0.217 (15)
F3B−0.0726 (17)0.7557 (13)0.244 (4)0.133 (8)0.217 (15)
F1B−0.0132 (15)0.629 (2)0.0833 (8)0.119 (6)0.217 (15)
C20.1369 (2)0.65458 (19)0.3615 (3)0.0581 (6)
C30.2008 (2)0.7593 (2)0.4227 (3)0.0620 (6)
H30.16070.83160.38280.074*
C40.3252 (2)0.75674 (18)0.5442 (3)0.0575 (6)
H40.36850.82760.58570.069*
C50.3858 (2)0.64908 (16)0.6046 (2)0.0484 (5)
C80.5128 (2)0.64594 (16)0.7435 (2)0.0503 (5)
N10.6164 (2)0.72612 (19)0.7499 (3)0.0731 (6)
H1N0.620 (3)0.764 (3)0.665 (4)0.088*
H2N0.689 (3)0.717 (2)0.830 (4)0.088*
N20.51210 (16)0.56917 (14)0.85708 (19)0.0515 (5)
O10.63766 (15)0.57836 (13)0.98654 (18)0.0622 (5)
H1O0.618 (3)0.532 (2)1.059 (3)0.093*
C60.3222 (2)0.54448 (19)0.5390 (3)0.0622 (6)
H60.36330.47200.57650.075*
C70.1980 (2)0.5470 (2)0.4181 (3)0.0679 (7)
H70.15540.47630.37470.081*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0610 (14)0.104 (2)0.0610 (14)0.0069 (14)0.0127 (11)0.0105 (14)
F1A0.099 (2)0.128 (3)0.101 (3)0.0203 (16)−0.0095 (18)0.0460 (19)
F2A0.105 (2)0.156 (4)0.085 (2)0.026 (2)−0.027 (2)−0.034 (2)
F3A0.0503 (12)0.200 (5)0.0912 (19)0.0029 (18)0.0178 (11)0.032 (2)
F2B0.071 (8)0.173 (13)0.131 (12)−0.053 (8)−0.019 (7)0.066 (9)
F3B0.075 (7)0.144 (11)0.154 (15)0.039 (7)−0.020 (8)−0.008 (9)
F1B0.061 (5)0.216 (15)0.075 (6)0.026 (7)0.010 (4)0.049 (8)
C20.0521 (11)0.0711 (14)0.0523 (11)0.0048 (10)0.0152 (9)0.0074 (10)
C30.0615 (13)0.0589 (13)0.0664 (13)0.0101 (10)0.0177 (11)0.0179 (10)
C40.0622 (12)0.0453 (11)0.0645 (12)−0.0022 (9)0.0149 (10)0.0077 (9)
C50.0508 (11)0.0461 (11)0.0500 (10)0.0000 (8)0.0161 (8)0.0033 (8)
C80.0513 (11)0.0430 (10)0.0567 (11)0.0002 (8)0.0136 (9)−0.0008 (8)
N10.0646 (12)0.0725 (13)0.0765 (14)−0.0214 (10)0.0071 (10)0.0161 (11)
N20.0519 (9)0.0474 (9)0.0516 (9)0.0000 (7)0.0062 (7)0.0021 (7)
O10.0586 (9)0.0609 (10)0.0585 (9)−0.0033 (7)−0.0009 (7)0.0033 (7)
C60.0634 (13)0.0451 (11)0.0709 (14)0.0038 (9)0.0035 (11)0.0016 (9)
C70.0663 (14)0.0583 (13)0.0718 (14)−0.0050 (10)0.0042 (11)−0.0059 (10)
Geometric parameters (Å, º) top
C1—F2A1.316 (3)C4—H40.9300
C1—F3A1.318 (3)C5—C61.381 (3)
C1—F1B1.323 (3)C5—C81.483 (3)
C1—F1A1.324 (3)C8—N21.289 (2)
C1—F3B1.328 (3)C8—N11.354 (3)
C1—F2B1.330 (3)N1—H1N0.84 (3)
C1—C21.498 (3)N1—H2N0.86 (3)
C2—C31.374 (3)N2—O11.432 (2)
C2—C71.383 (3)O1—H1O0.86 (3)
C3—C41.385 (3)C6—C71.382 (3)
C3—H30.9300C6—H60.9300
C4—C51.389 (3)C7—H70.9300
F2A—C1—F3A108.9 (3)C2—C3—C4119.77 (18)
F2A—C1—F1B28.5 (8)C2—C3—H3120.1
F3A—C1—F1B121.1 (7)C4—C3—H3120.1
F2A—C1—F1A104.7 (3)C3—C4—C5120.46 (18)
F3A—C1—F1A105.3 (3)C3—C4—H4119.8
F1B—C1—F1A76.5 (9)C5—C4—H4119.8
F2A—C1—F3B131.8 (9)C6—C5—C4119.17 (19)
F3A—C1—F3B72.1 (12)C6—C5—C8120.16 (17)
F1B—C1—F3B107.9 (10)C4—C5—C8120.59 (17)
F1A—C1—F3B37.4 (13)N2—C8—N1124.23 (19)
F2A—C1—F2B71.5 (14)N2—C8—C5115.93 (16)
F3A—C1—F2B41.1 (14)N1—C8—C5119.69 (18)
F1B—C1—F2B93.3 (11)C8—N1—H1N120 (2)
F1A—C1—F2B131.5 (9)C8—N1—H2N115.4 (18)
F3B—C1—F2B109.3 (11)H1N—N1—H2N121 (3)
F2A—C1—C2111.3 (3)C8—N2—O1110.41 (15)
F3A—C1—C2112.3 (2)N2—O1—H1O100.9 (19)
F1B—C1—C2120.3 (6)C5—C6—C7120.37 (19)
F1A—C1—C2113.9 (2)C5—C6—H6119.8
F3B—C1—C2112.2 (7)C7—C6—H6119.8
F2B—C1—C2112.1 (6)C6—C7—C2120.0 (2)
C3—C2—C7120.2 (2)C6—C7—H7120.0
C3—C2—C1120.58 (19)C2—C7—H7120.0
C7—C2—C1119.1 (2)
F2A—C1—C2—C3137.2 (4)C2—C3—C4—C50.0 (3)
F3A—C1—C2—C3−100.5 (5)C3—C4—C5—C61.6 (3)
F1B—C1—C2—C3107.0 (12)C3—C4—C5—C8−175.20 (18)
F1A—C1—C2—C319.2 (4)C6—C5—C8—N2−41.5 (3)
F3B—C1—C2—C3−21.5 (17)C4—C5—C8—N2135.3 (2)
F2B—C1—C2—C3−145.0 (19)C6—C5—C8—N1142.6 (2)
F2A—C1—C2—C7−46.0 (5)C4—C5—C8—N1−40.6 (3)
F3A—C1—C2—C776.4 (5)N1—C8—N2—O1−2.0 (3)
F1B—C1—C2—C7−76.1 (12)C5—C8—N2—O1−177.71 (15)
F1A—C1—C2—C7−164.0 (4)C4—C5—C6—C7−1.7 (3)
F3B—C1—C2—C7155.3 (17)C8—C5—C6—C7175.06 (19)
F2B—C1—C2—C731.9 (19)C5—C6—C7—C20.3 (4)
C7—C2—C3—C4−1.5 (3)C3—C2—C7—C61.3 (4)
C1—C2—C3—C4175.34 (19)C1—C2—C7—C6−175.5 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···O1i0.84 (3)2.36 (3)3.165 (3)161 (3)
O1—H1O···N2ii0.86 (3)1.98 (3)2.766 (2)152 (3)
Symmetry codes: (i) x, −y+3/2, z−1/2; (ii) −x+1, −y+1, −z+2.

Experimental details

Crystal data
Chemical formulaC8H7F3N2O
Mr204.16
Crystal system, space groupMonoclinic, P21/c
Temperature (K)293
a, b, c (Å)9.8706 (8), 11.2540 (12), 8.4033 (7)
β (°) 104.61 (2)
V (Å3)903.29 (16)
Z4
Radiation typeMo Kα
µ (mm−1)0.14
Crystal size (mm)0.32 × 0.24 × 0.20
Data collection
DiffractometerRigaku R-AXIS RAPID
diffractometer
Absorption correctionMulti-scan
(ABSCOR; Higashi, 1995)
Tmin, Tmax0.946, 0.972
No. of measured, independent and
observed [I > 2σ(I)] reflections		8605, 2058, 1324
Rint0.077
(sin θ/λ)max (Å−1)0.648
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.056, 0.183, 1.07
No. of reflections2058
No. of parameters164
No. of restraints42
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)0.23, −0.29

Computer programs: PROCESS-AUTO (Rigaku, 2006), CrystalStructure (Rigaku, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···O1i0.84 (3)2.36 (3)3.165 (3)161 (3)
O1—H1O···N2ii0.86 (3)1.98 (3)2.766 (2)152 (3)
Symmetry codes: (i) x, −y+3/2, z−1/2; (ii) −x+1, −y+1, −z+2.
 

Acknowledgements

The authors gratefully acknowledge financial support from the Education Department of Liaoning Province (2009 A 265) and Liaoning University.

References

First citationAakeröy, C. B., Beatty, A. M. & Leinen, D. S. (2000). CrystEngComm, 2, 145–150.  Google Scholar
 First citationFarrugia, L. J. (1997). J. Appl. Cryst. 30, 565.  CrossRef IUCr Journals Google Scholar
 First citationFarrugia, L. J. (1999). J. Appl. Cryst. 32, 837–838.  CrossRef CAS IUCr Journals Google Scholar
 First citationHigashi, T. (1995). ABSCOR. Rigaku Corporation, Tokyo, Japan.  Google Scholar
 First citationOrama, M. & Saarinen, H. (1996). Acta Chem. Scand. 50, 1087–1091.  CrossRef CAS Google Scholar
 First citationRai, N. P., Narayanaswamy, V. K., Govender, T., Manuprasad, B. K., Shashikanth, S. & Arunachalam, P. N. (2010). Eur. J. Med. Chem. 45, 2677–2682.  Web of Science CrossRef CAS PubMed Google Scholar
 First citationRigaku (2006). PROCESS-AUTO. Rigaku Corporation, Tokyo, Japan.  Google Scholar
 First citationRigaku (2007). CrystalStructure. Rigaku Corporation, Tokyo, Japan, and Rigaku Americas, The Woodlands, Texas, USA.  Google Scholar
 First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 4| April 2011| Page o859
doi:10.1107/S1600536811005022
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