(Z)-1-(2,4-Difluoro­phen­yl)-2-(1H-1,2,4-triazol-1-yl)ethanone oxime

Abstract

In the title compound, C₁₀H₈F₂N₄O, the dihedral angle between the rings is 65.4 (1)°. In the crystal, inter­molecular O—H⋯N and C—H⋯F hydrogen bonds link the mol­ecules in a stacked arrangement along the a and c axes, respectively.

Related literature

For applications of related compounds, see: Foroumadi et al. (2003 ▶); Mixich & Thiele (1979 ▶); Wolfgang et al. (1981 ▶). For a related structure, see: Tao et al. (2007 ▶). For standard bond lengths, see: Allen et al. (1987 ▶).

Experimental

Crystal data

• C₁₀H₈F₂N₄O

• M _r = 238.20

• Monoclinic,

• a = 8.6320 (17) Å

• b = 12.433 (3) Å

• c = 10.417 (2) Å

• β = 104.85 (3)°

• V = 1080.6 (4) ų

• Z = 4

• Mo Kα radiation

• μ = 0.12 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 = 0.964, T _max = 0.988

• 3127 measured reflections

• 1987 independent reflections

• 1217 reflections with I > 2σ(I)

• R _int = 0.042

• 3 standard reflections every 200 reflections intensity decay: 1%

Refinement

• R[F ² > 2σ(F ²)] = 0.060

• wR(F ²) = 0.171

• S = 1.01

• 1987 reflections

• 154 parameters

• H-atom parameters constrained

• Δρ_max = 0.53 e Å⁻³

• Δρ_min = −0.22 e Å⁻³

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994 ▶); 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: PLATON (Spek, 2009 ▶); software used to prepare material for publication: SHELXTL (Sheldrick, 2008 ▶).

Supplementary Material

Supplementary material file. DOI: 10.1107/S1600536811050008/zq2136Isup3.cml

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

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1A⋯N4i	0.82	1.94	2.764 (3)	176
C10—H10⋯F1ii	0.93	2.47	3.289 (4)	148

Symmetry codes: (i) ; (ii) .

supplementary crystallographic information

Comment

The title compound, C₁₀H₈O₁N₄F₂, is the key intermediate in the synthesis of a new kind of antifungal drug (Tao et al., 2007; Foroumadi et al., 2003; Wolfgang et al., 1981) and exhibits a chemical structure similar to oxiconazole (Mixich & Thiele, 1979). We designed and synthesized the title compound, and we herein report its crystal structure (Fig. 1).

The bond lengths are within normal ranges (Allen et al., 1987). The dihedral angle between rings A (N2-N4/C9/C10) and B (C1-C6) is 65.4 (1) °. In the crystal structure, intermolecular intermolecular O–H···N and C-H···F hydrogen bonds (Table 2) link the molecules in a stacked arrangement along along the a and c axes, respectively (Fig. 2).

Experimental

Hydroxylammonium chloride (3 g, 43.2 mmol) dissolved in ethanol (20 ml) was dropwise added to a solution of 1-(2,4-difluorophenyl)-2-(1H-1,2,4-triazol-1-yl)ethanone (5 g,22.4 mmol) in ethanol (50 ml) which contained CH₃COONa (4 g, 48.8 mmol) under reflux conditions for 4 h. The mixture was placed in ice-water (100 ml), and the crystalline product was isolated by filtration, washed with water (100 ml). The crystals were obtained by dissolving the product in ethanol (20 ml) and evaporating acetone slowly at room temperature for about 7 d.

Refinement

The H atom of the hydroxy group was located in a Fourier difference map but was constrained to ride on the parent atom with O—H = 0.82 Å and U_iso(H) = 1.5U_eq(O). The other H atoms were positioned geometrically with C—H = 0.93 Å (aromatic) and 0.97 Å (methylene) and constrained to ride on their parent atoms with U_iso(H) = 1.2U_eq(C).

Figures

Fig. 1.

The molecular structure of the title compound showing displacement ellipsoids drawn at the 50% probability level.

Fig. 2.

A packing diagram of the title compound. Hydrogen bonds are shown as dashed lines.

Crystal data

C10H8F2N4O	F(000) = 488
Mr = 238.20	Dx = 1.464 Mg m−3
Monoclinic, P21/n	Melting point: 400 K
Hall symbol: -P 2yn	Mo Kα radiation, λ = 0.71073 Å
a = 8.6320 (17) Å	Cell parameters from 25 reflections
b = 12.433 (3) Å	θ = 9–13°
c = 10.417 (2) Å	µ = 0.12 mm−1
β = 104.85 (3)°	T = 293 K
V = 1080.6 (4) Å3	Black, white
Z = 4	0.30 × 0.20 × 0.10 mm

Data collection

Enraf–Nonius CAD-4 diffractometer	1217 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.042
graphite	θmax = 25.4°, θmin = 2.6°
ω/2θ scans	h = 0→10
Absorption correction: ψ scan (North et al., 1968)	k = −5→14
Tmin = 0.964, Tmax = 0.988	l = −12→12
3127 measured reflections	3 standard reflections every 200 reflections
1987 independent reflections	intensity decay: 1%

Refinement

Refinement on F2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.060	H-atom parameters constrained
wR(F2) = 0.171	w = 1/[σ2(Fo2) + (0.090P)2] where P = (Fo2 + 2Fc2)/3
S = 1.01	(Δ/σ)max < 0.001
1987 reflections	Δρmax = 0.53 e Å−3
154 parameters	Δρmin = −0.22 e Å−3
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008)
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.034 (5)

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
O1	−0.0689 (3)	0.1304 (2)	0.0266 (2)	0.0885 (7)
H1A	−0.1670	0.1325	0.0102	0.133*
F1	0.0628 (2)	0.39466 (19)	−0.12253 (18)	0.1082 (8)
N1	−0.0109 (3)	0.2303 (3)	0.0363 (2)	0.0787 (8)
C1	0.3526 (3)	0.3487 (3)	0.1896 (3)	0.0689 (8)
H1	0.3862	0.2944	0.2520	0.083*
N2	0.3725 (2)	0.13025 (17)	0.0097 (2)	0.0535 (6)
C2	0.4296 (4)	0.4452 (3)	0.2083 (3)	0.0880 (11)
H2	0.5142	0.4572	0.2826	0.106*
F2	0.4618 (4)	0.61943 (18)	0.1316 (3)	0.1508 (12)
N3	0.3361 (2)	0.1384 (2)	−0.1226 (2)	0.0654 (7)
C3	0.3801 (5)	0.5240 (3)	0.1156 (4)	0.0917 (10)
N4	0.6005 (2)	0.1436 (2)	−0.0387 (2)	0.0679 (7)
C4	0.2564 (4)	0.5106 (3)	0.0065 (3)	0.0944 (11)
H4	0.2229	0.5659	−0.0545	0.113*
C5	0.1822 (3)	0.4114 (3)	−0.0101 (3)	0.0707 (9)
C6	0.2250 (3)	0.3288 (2)	0.0798 (2)	0.0538 (7)
C7	0.1461 (3)	0.2225 (3)	0.0625 (2)	0.0619 (8)
C8	0.2467 (3)	0.1224 (2)	0.0803 (3)	0.0605 (8)
H8A	0.2951	0.1110	0.1741	0.073*
H8B	0.1789	0.0609	0.0471	0.073*
C9	0.4781 (3)	0.1454 (2)	−0.1470 (3)	0.0663 (8)
H9	0.4918	0.1511	−0.2324	0.080*
C10	0.5286 (3)	0.1362 (2)	0.0578 (3)	0.0597 (7)
H10	0.5810	0.1353	0.1477	0.072*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
O1	0.0712 (14)	0.0982 (19)	0.0951 (17)	0.0097 (14)	0.0198 (12)	−0.0037 (14)
F1	0.0744 (12)	0.160 (2)	0.0717 (12)	−0.0057 (12)	−0.0146 (10)	0.0297 (11)
N1	0.0610 (14)	0.115 (3)	0.0608 (15)	−0.0278 (15)	0.0177 (11)	−0.0027 (15)
C1	0.0595 (16)	0.078 (2)	0.0599 (16)	0.0107 (16)	−0.0024 (13)	−0.0075 (15)
N2	0.0337 (10)	0.0662 (15)	0.0611 (13)	−0.0045 (10)	0.0133 (9)	0.0006 (11)
C2	0.095 (2)	0.087 (3)	0.0639 (19)	0.012 (2)	−0.0120 (18)	−0.0177 (19)
F2	0.183 (3)	0.0744 (16)	0.161 (2)	−0.0211 (16)	−0.017 (2)	−0.0079 (15)
N3	0.0441 (11)	0.093 (2)	0.0577 (13)	−0.0116 (12)	0.0107 (10)	−0.0005 (12)
C3	0.106 (3)	0.067 (2)	0.091 (2)	0.002 (2)	0.004 (2)	−0.014 (2)
N4	0.0449 (12)	0.0795 (18)	0.0822 (16)	−0.0011 (11)	0.0216 (12)	−0.0008 (13)
C4	0.108 (3)	0.078 (3)	0.085 (2)	0.016 (2)	0.002 (2)	0.014 (2)
C5	0.0594 (16)	0.100 (3)	0.0456 (15)	0.0192 (18)	0.0007 (13)	0.0074 (16)
C6	0.0283 (11)	0.084 (2)	0.0503 (14)	0.0060 (12)	0.0120 (10)	−0.0023 (14)
C7	0.0463 (13)	0.096 (2)	0.0464 (14)	0.0039 (15)	0.0175 (11)	0.0027 (14)
C8	0.0363 (12)	0.080 (2)	0.0674 (17)	−0.0076 (13)	0.0175 (12)	0.0078 (15)
C9	0.0470 (14)	0.089 (2)	0.0659 (17)	−0.0109 (15)	0.0205 (13)	−0.0046 (16)
C10	0.0297 (11)	0.075 (2)	0.0724 (17)	0.0046 (12)	0.0091 (11)	0.0088 (14)

Geometric parameters (Å, °)

O1—N1	1.334 (3)	N3—C9	1.317 (3)
O1—H1A	0.8200	C3—C4	1.356 (5)
F1—C5	1.364 (3)	N4—C10	1.313 (3)
N1—C7	1.315 (3)	N4—C9	1.333 (3)
C1—C2	1.362 (4)	C4—C5	1.380 (5)
C1—C6	1.392 (3)	C4—H4	0.9300
C1—H1	0.9300	C5—C6	1.375 (4)
N2—C10	1.314 (3)	C6—C7	1.477 (4)
N2—N3	1.337 (3)	C7—C8	1.502 (4)
N2—C8	1.463 (3)	C8—H8A	0.9700
C2—C3	1.365 (5)	C8—H8B	0.9700
C2—H2	0.9300	C9—H9	0.9300
F2—C3	1.368 (4)	C10—H10	0.9300
N1—O1—H1A	109.5	F1—C5—C4	117.9 (3)
C7—N1—O1	107.1 (3)	C6—C5—C4	123.2 (3)
C2—C1—C6	121.9 (3)	C5—C6—C1	116.4 (3)
C2—C1—H1	119.0	C5—C6—C7	123.4 (2)
C6—C1—H1	119.0	C1—C6—C7	120.1 (3)
C10—N2—N3	109.6 (2)	N1—C7—C6	112.2 (3)
C10—N2—C8	129.3 (2)	N1—C7—C8	128.2 (3)
N3—N2—C8	120.97 (18)	C6—C7—C8	119.5 (2)
C1—C2—C3	118.6 (3)	N2—C8—C7	111.3 (2)
C1—C2—H2	120.7	N2—C8—H8A	109.4
C3—C2—H2	120.7	C7—C8—H8A	109.4
C9—N3—N2	102.7 (2)	N2—C8—H8B	109.4
C4—C3—C2	122.8 (4)	C7—C8—H8B	109.4
C4—C3—F2	118.6 (4)	H8A—C8—H8B	108.0
C2—C3—F2	118.6 (3)	N3—C9—N4	114.2 (2)
C10—N4—C9	102.8 (2)	N3—C9—H9	122.9
C3—C4—C5	117.1 (3)	N4—C9—H9	122.9
C3—C4—H4	121.5	N4—C10—N2	110.6 (2)
C5—C4—H4	121.5	N4—C10—H10	124.7
F1—C5—C6	118.8 (3)	N2—C10—H10	124.7
C6—C1—C2—C3	−0.5 (5)	O1—N1—C7—C6	−178.2 (2)
C10—N2—N3—C9	2.1 (3)	O1—N1—C7—C8	−0.5 (4)
C8—N2—N3—C9	179.0 (2)	C5—C6—C7—N1	−50.9 (3)
C1—C2—C3—C4	0.7 (6)	C1—C6—C7—N1	130.8 (3)
C1—C2—C3—F2	−177.3 (3)	C5—C6—C7—C8	131.1 (3)
C2—C3—C4—C5	−1.5 (6)	C1—C6—C7—C8	−47.1 (3)
F2—C3—C4—C5	176.6 (3)	C10—N2—C8—C7	112.4 (3)
C3—C4—C5—F1	−176.8 (3)	N3—N2—C8—C7	−63.8 (3)
C3—C4—C5—C6	2.0 (5)	N1—C7—C8—N2	135.8 (3)
F1—C5—C6—C1	177.1 (2)	C6—C7—C8—N2	−46.7 (3)
C4—C5—C6—C1	−1.7 (4)	N2—N3—C9—N4	−0.9 (3)
F1—C5—C6—C7	−1.2 (4)	C10—N4—C9—N3	−0.7 (4)
C4—C5—C6—C7	180.0 (3)	C9—N4—C10—N2	2.0 (3)
C2—C1—C6—C5	0.9 (4)	N3—N2—C10—N4	−2.7 (3)
C2—C1—C6—C7	179.3 (3)	C8—N2—C10—N4	−179.2 (3)

Hydrogen-bond geometry (Å, °)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1A···N4i	0.82	1.94	2.764 (3)	176
C10—H10···F1ii	0.93	2.47	3.289 (4)	148

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