(Z)-1-(2,4-Difluoro­phen­yl)-3-(4-fluoro­phen­yl)-2-(1H-1,2,4-triazol-1-yl)prop-2-en-1-one

Yin, B.-T.; Lv, J.-S.; Wang, Y.; Zhou, C.-H.

doi:10.1107/S1600536812012123

organic compounds

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ISSN: 2056-9890

Volume 68| Part 4| April 2012| Page o1197

doi:10.1107/S1600536812012123

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(Z)-1-(2,4-Difluorophenyl)-3-(4-fluorophenyl)-2-(1H-1,2,4-triazol-1-yl)prop-2-en-1-one

Ben-Tao Yin,^a Jing-Song Lv,^a Yan Wang ^a and Cheng-He Zhou ^a ^*

^aLaboratory of Bioorganic & Medicinal Chemistry, School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, People's Republic of China
^*Correspondence e-mail: zhouch@swu.edu.cn

(Received 13 March 2012; accepted 21 March 2012; online 28 March 2012)

In the title molecule, C₁₇H₁₀F₃N₃O, the C=C bond connecting the triazole ring and 4-fluorophenyl groups adopts a Z conformation. The triazole ring forms dihedral angles of 15.3 (1) and 63.5 (1)°, with the 2,4-difluoro-substituted and 4-fluoro-substituted benzene rings, respectively. The dihedral angle between the two benzene rings is 51.8 (1)°.

Related literature

For the pharmacological activity of triazole derivatives, see: Wang & Zhou (2011 ); Zhou & Wang (2012 ). For the biological activity of chalcones, see: Jin et al. (2010 ). For related structures, see: Wang et al. (2009 ); Yan et al. (2009 ). For the synthesis, see: Yan et al. (2009).

Experimental

Crystal data

C₁₇H₁₀F₃N₃O
M_r = 329.28
Monoclinic, P 2₁ /c
a = 11.735 (6) Å
b = 7.698 (4) Å
c = 17.065 (7) Å
β = 110.45 (3)°
V = 1444.4 (12) Å³
Z = 4
Mo Kα radiation
μ = 0.12 mm⁻¹
T = 293 K
0.19 × 0.17 × 0.16 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ) T_min = 0.977, T_max = 0.980
7601 measured reflections
2840 independent reflections
2095 reflections with I > 2σ(I)
R_int = 0.027

Refinement

R[F² > 2σ(F²)] = 0.042
wR(F²) = 0.100
S = 1.01
2840 reflections
217 parameters
H-atom parameters constrained
Δρ_max = 0.15 e Å⁻³
Δρ_min = −0.21 e Å⁻³

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); 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: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536812012123/lh5435sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812012123/lh5435Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812012123/lh5435Isup3.cml

checkCIF report

Comment top

Triazole compounds exhibit broad bioactive spectrum and the developments of new triazole derivatives as potential bioactive agents have become an active topic in medicinal chemistry (Wang & Zhou, 2011; Zhou & Wang, 2012). Chalcones have been paid increasingly special attention for their diverse biological activities such as antimicrobial, anticancer, antiviral and anti-inflammatory ones and so on (Jin et al., 2010). Our interest is to develop novel triazole-derived chalcone compounds as medicinal agents. We have already synthesized and reported related structures of triazolylchalcones (Wang et al., 2009; Yan et al., 2009). Herein, we report the crystal structure of the title compound (I).

The molecular structure of (I) is shown in Fig. 1. The C═C bond connecting the triazole ring and 4-fluorophenyl groups adopts a Z geometry. The atoms in the region of the C═C bond have an essentially planar arrangement i.e. the r.m.s. deviation the atoms C7/C8/C11/C12/N1 is 0.0480 Å. The torsion angles of C12–C11═C8–C7 and C12–C11═C8–N1 are -169.35 (16)° and 7.1 (3)°. The triazole ring forms dihedral angles of 15.3 (1)° and 63.5 (1)°, with the 2,4-difluoro substituted (C1-C6) and 4-fluoro substituted (C12-C17) benzene rings, respectively. The dihedral angles between the two benzene rings is 51.8 (1)°.

Related literature top

For the pharmacological activity of triazole derivatives, see: Wang & Zhou (2011); Zhou & Wang (2012). For the biological activity of chalcones, see: Jin et al. (2010). For related structures, see: Wang et al. (2009); Yan et al. (2009). For the synthesis, see: Yan et al. (2009).

Experimental top

Compound (I) was prepared according to the procedure of Yan et al. (2009). A mixture of 1-(2,4-difluorophenyl)-2-(1H-1,2,4-triazol-1-yl) ethanone (3.07 g, 13.8 mmol) and 4-fluorobenzaldehyde (1.89 g, 15.3 mmol) in toluene (30 mL) using glacial acetic acid (0.08 mL, 1.4 mmol) as catalyst was refluxed. After the reaction was complete (monitored by TLC, petroleum ether/ethyl acetate, 10/1, V/V), the solvent was removed. The residue was dissolved in dichloromethane (30 mL) and washed with water (3x30 mL). The resulting phase was dried over anhydrous sodium sulfate, concentrated under reduced pressure and then purified by silica gel column chromatography eluting with petroleum ether/ethyl acetate (10/1-2/1, V/V) to give the title compound (I) (2.578 g) as solid. Crystals suitable for X-ray analysis were grown from a mixed solution of (I) in ethyl acetate and petroleum ether by slow evaporation at room temperature.

Structure description top

For the pharmacological activity of triazole derivatives, see: Wang & Zhou (2011); Zhou & Wang (2012). For the biological activity of chalcones, see: Jin et al. (2010). For related structures, see: Wang et al. (2009); Yan et al. (2009). For the synthesis, see: Yan et al. (2009).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); 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).

Figures top

Fig. 1. The molecular structure of (I), showing the displacement ellipsoids are drawn at the 50% probability level.

(Z)-1-(2,4-Difluorophenyl)-3-(4-fluorophenyl)-2-(1H-1,2,4- triazol-1-yl)prop-2-en-1-one top

Crystal data top

C₁₇H₁₀F₃N₃O	F(000) = 672
M_r = 329.28	D_x = 1.514 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 2158 reflections
a = 11.735 (6) Å	θ = 2.9–23.2°
b = 7.698 (4) Å	µ = 0.12 mm⁻¹
c = 17.065 (7) Å	T = 293 K
β = 110.45 (3)°	Block, colourless
V = 1444.4 (12) Å³	0.19 × 0.17 × 0.16 mm
Z = 4

Data collection top

Bruker APEXII CCD diffractometer	2840 independent reflections
Radiation source: fine-focus sealed tube	2095 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.027
φ and ω scans	θ_max = 26.0°, θ_min = 2.6°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −14→14
T_min = 0.977, T_max = 0.980	k = −9→9
7601 measured reflections	l = −21→16

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)] = 0.042	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.100	H-atom parameters constrained
S = 1.01	w = 1/[σ²(F_o²) + (0.0398P)² + 0.3484P] where P = (F_o² + 2F_c²)/3
2840 reflections	(Δ/σ)_max = 0.001
217 parameters	Δρ_max = 0.15 e Å⁻³
0 restraints	Δρ_min = −0.21 e Å⁻³

Crystal data top

C₁₇H₁₀F₃N₃O	V = 1444.4 (12) Å³
M_r = 329.28	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 11.735 (6) Å	µ = 0.12 mm⁻¹
b = 7.698 (4) Å	T = 293 K
c = 17.065 (7) Å	0.19 × 0.17 × 0.16 mm
β = 110.45 (3)°

Data collection top

Bruker APEXII CCD diffractometer	2840 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2009)	2095 reflections with I > 2σ(I)
T_min = 0.977, T_max = 0.980	R_int = 0.027
7601 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.042	0 restraints
wR(F²) = 0.100	H-atom parameters constrained
S = 1.01	Δρ_max = 0.15 e Å⁻³
2840 reflections	Δρ_min = −0.21 e Å⁻³
217 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
F1	−0.10204 (11)	0.63601 (19)	0.88238 (9)	0.0882 (4)
F2	0.09918 (11)	0.6680 (2)	0.69415 (7)	0.0836 (4)
F3	0.87808 (11)	1.03042 (17)	1.09542 (8)	0.0816 (4)
O1	0.29519 (13)	0.4323 (2)	0.74119 (9)	0.0862 (5)
N1	0.52550 (12)	0.49839 (18)	0.83262 (8)	0.0416 (3)
N2	0.61373 (13)	0.40221 (19)	0.88775 (9)	0.0498 (4)
N3	0.64451 (15)	0.4248 (2)	0.76604 (10)	0.0619 (5)
C1	−0.00130 (16)	0.6098 (3)	0.86429 (13)	0.0551 (5)
C2	−0.00402 (16)	0.6532 (3)	0.78670 (12)	0.0579 (5)
H2A	−0.0732	0.7000	0.7469	0.070*
C3	0.09943 (16)	0.6248 (2)	0.77016 (10)	0.0508 (4)
C4	0.20312 (15)	0.5587 (2)	0.82741 (10)	0.0432 (4)
C5	0.20019 (16)	0.5199 (2)	0.90521 (11)	0.0493 (4)
H5A	0.2696	0.4763	0.9460	0.059*
C6	0.09753 (18)	0.5442 (3)	0.92381 (12)	0.0576 (5)
H6A	0.0958	0.5161	0.9764	0.069*
C7	0.30928 (16)	0.5142 (2)	0.80365 (11)	0.0487 (4)
C8	0.43130 (14)	0.5720 (2)	0.85556 (9)	0.0392 (4)
C9	0.54611 (17)	0.5086 (3)	0.76135 (11)	0.0550 (5)
H9A	0.4968	0.5679	0.7142	0.066*
C10	0.68092 (17)	0.3624 (3)	0.84397 (12)	0.0565 (5)
H10A	0.7504	0.2943	0.8656	0.068*
C11	0.45564 (14)	0.6885 (2)	0.91621 (9)	0.0393 (4)
H11A	0.3900	0.7203	0.9317	0.047*
C12	0.56903 (15)	0.7736 (2)	0.96193 (9)	0.0382 (4)
C13	0.65828 (16)	0.8061 (2)	0.92821 (10)	0.0458 (4)
H13A	0.6477	0.7676	0.8745	0.055*
C14	0.76122 (17)	0.8936 (2)	0.97250 (11)	0.0528 (5)
H14A	0.8206	0.9166	0.9494	0.063*
C15	0.77542 (17)	0.9468 (2)	1.05143 (12)	0.0529 (5)
C16	0.69124 (17)	0.9189 (2)	1.08757 (11)	0.0509 (4)
H16A	0.7039	0.9559	1.1419	0.061*
C17	0.58720 (16)	0.8347 (2)	1.04174 (10)	0.0443 (4)
H17A	0.5268	0.8179	1.0646	0.053*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
F1	0.0522 (7)	0.1184 (11)	0.1063 (10)	0.0076 (7)	0.0433 (7)	−0.0049 (9)
F2	0.0626 (8)	0.1346 (12)	0.0478 (6)	−0.0146 (7)	0.0117 (5)	0.0233 (7)
F3	0.0704 (8)	0.0765 (8)	0.0851 (9)	−0.0227 (7)	0.0113 (7)	−0.0198 (7)
O1	0.0622 (9)	0.1310 (14)	0.0718 (9)	−0.0220 (9)	0.0314 (8)	−0.0551 (10)
N1	0.0459 (8)	0.0450 (8)	0.0399 (7)	0.0012 (7)	0.0225 (6)	−0.0033 (6)
N2	0.0484 (9)	0.0524 (9)	0.0539 (9)	0.0084 (7)	0.0243 (7)	0.0022 (7)
N3	0.0605 (11)	0.0776 (12)	0.0593 (10)	−0.0020 (9)	0.0359 (9)	−0.0177 (9)
C1	0.0413 (11)	0.0612 (12)	0.0693 (13)	−0.0024 (9)	0.0276 (9)	−0.0047 (10)
C2	0.0383 (10)	0.0628 (12)	0.0636 (12)	−0.0012 (9)	0.0063 (9)	0.0031 (10)
C3	0.0467 (11)	0.0618 (11)	0.0412 (9)	−0.0114 (9)	0.0120 (8)	0.0041 (9)
C4	0.0416 (10)	0.0451 (9)	0.0442 (9)	−0.0038 (8)	0.0166 (8)	−0.0025 (8)
C5	0.0488 (10)	0.0527 (11)	0.0484 (10)	0.0081 (9)	0.0194 (8)	0.0069 (8)
C6	0.0578 (12)	0.0678 (13)	0.0562 (11)	0.0033 (10)	0.0312 (10)	0.0060 (10)
C7	0.0496 (10)	0.0573 (11)	0.0432 (9)	−0.0040 (9)	0.0212 (8)	−0.0076 (9)
C8	0.0428 (9)	0.0425 (9)	0.0371 (8)	0.0045 (7)	0.0202 (7)	0.0018 (7)
C9	0.0610 (12)	0.0677 (12)	0.0429 (10)	−0.0030 (10)	0.0264 (9)	−0.0078 (9)
C10	0.0490 (11)	0.0603 (12)	0.0664 (12)	0.0040 (9)	0.0279 (10)	−0.0105 (10)
C11	0.0416 (9)	0.0414 (9)	0.0387 (8)	0.0064 (7)	0.0188 (7)	0.0038 (7)
C12	0.0442 (9)	0.0348 (8)	0.0376 (8)	0.0078 (7)	0.0167 (7)	0.0023 (7)
C13	0.0543 (11)	0.0454 (10)	0.0409 (9)	−0.0011 (9)	0.0206 (8)	−0.0016 (8)
C14	0.0535 (11)	0.0493 (11)	0.0609 (11)	−0.0043 (9)	0.0266 (9)	0.0004 (9)
C15	0.0527 (11)	0.0401 (10)	0.0560 (11)	−0.0032 (9)	0.0065 (9)	−0.0048 (9)
C16	0.0632 (12)	0.0448 (10)	0.0422 (9)	0.0062 (9)	0.0151 (9)	−0.0045 (8)
C17	0.0534 (11)	0.0402 (9)	0.0432 (9)	0.0070 (8)	0.0218 (8)	−0.0009 (8)

Geometric parameters (Å, º) top

F1—C1	1.337 (2)	C5—H5A	0.9300
F2—C3	1.3382 (19)	C6—H6A	0.9300
F3—C15	1.341 (2)	C7—C8	1.465 (2)
O1—C7	1.199 (2)	C8—C11	1.323 (2)
N1—C9	1.323 (2)	C9—H9A	0.9300
N1—N2	1.351 (2)	C10—H10A	0.9300
N1—C8	1.414 (2)	C11—C12	1.443 (2)
N2—C10	1.298 (2)	C11—H11A	0.9300
N3—C9	1.300 (2)	C12—C13	1.383 (2)
N3—C10	1.336 (2)	C12—C17	1.385 (2)
C1—C6	1.345 (3)	C13—C14	1.359 (3)
C1—C2	1.355 (3)	C13—H13A	0.9300
C2—C3	1.357 (3)	C14—C15	1.361 (2)
C2—H2A	0.9300	C14—H14A	0.9300
C3—C4	1.365 (2)	C15—C16	1.352 (3)
C4—C5	1.373 (2)	C16—C17	1.362 (3)
C4—C7	1.479 (2)	C16—H16A	0.9300
C5—C6	1.362 (2)	C17—H17A	0.9300

C9—N1—N2	109.34 (14)	N1—C8—C7	113.87 (14)
C9—N1—C8	130.00 (15)	N3—C9—N1	110.95 (18)
N2—N1—C8	120.66 (12)	N3—C9—H9A	124.5
C10—N2—N1	101.56 (14)	N1—C9—H9A	124.5
C9—N3—C10	102.01 (15)	N2—C10—N3	116.13 (18)
F1—C1—C6	118.75 (17)	N2—C10—H10A	121.9
F1—C1—C2	117.86 (18)	N3—C10—H10A	121.9
C6—C1—C2	123.38 (17)	C8—C11—C12	129.55 (15)
C1—C2—C3	116.50 (18)	C8—C11—H11A	115.2
C1—C2—H2A	121.7	C12—C11—H11A	115.2
C3—C2—H2A	121.7	C13—C12—C17	117.96 (16)
F2—C3—C2	117.55 (17)	C13—C12—C11	123.14 (14)
F2—C3—C4	119.07 (16)	C17—C12—C11	118.80 (14)
C2—C3—C4	123.36 (16)	C14—C13—C12	120.92 (16)
C3—C4—C5	117.12 (16)	C14—C13—H13A	119.5
C3—C4—C7	121.05 (15)	C12—C13—H13A	119.5
C5—C4—C7	121.54 (16)	C13—C14—C15	118.50 (17)
C6—C5—C4	121.25 (17)	C13—C14—H14A	120.8
C6—C5—H5A	119.4	C15—C14—H14A	120.8
C4—C5—H5A	119.4	F3—C15—C16	118.53 (17)
C1—C6—C5	118.37 (17)	F3—C15—C14	118.29 (18)
C1—C6—H6A	120.8	C16—C15—C14	123.18 (17)
C5—C6—H6A	120.8	C15—C16—C17	117.69 (16)
O1—C7—C8	119.94 (16)	C15—C16—H16A	121.2
O1—C7—C4	119.85 (17)	C17—C16—H16A	121.2
C8—C7—C4	120.21 (15)	C16—C17—C12	121.70 (16)
C11—C8—N1	120.81 (15)	C16—C17—H17A	119.2
C11—C8—C7	125.23 (15)	C12—C17—H17A	119.2

C9—N1—N2—C10	0.01 (19)	O1—C7—C8—C11	166.70 (18)
C8—N1—N2—C10	−179.18 (15)	C4—C7—C8—C11	−12.5 (3)
F1—C1—C2—C3	−179.89 (17)	O1—C7—C8—N1	−9.9 (3)
C6—C1—C2—C3	1.0 (3)	C4—C7—C8—N1	170.88 (14)
C1—C2—C3—F2	−179.47 (17)	C10—N3—C9—N1	0.6 (2)
C1—C2—C3—C4	−1.0 (3)	N2—N1—C9—N3	−0.4 (2)
F2—C3—C4—C5	178.52 (16)	C8—N1—C9—N3	178.68 (16)
C2—C3—C4—C5	0.1 (3)	N1—N2—C10—N3	0.4 (2)
F2—C3—C4—C7	−7.6 (3)	C9—N3—C10—N2	−0.6 (2)
C2—C3—C4—C7	173.93 (18)	N1—C8—C11—C12	7.1 (3)
C3—C4—C5—C6	0.9 (3)	C7—C8—C11—C12	−169.35 (16)
C7—C4—C5—C6	−172.91 (17)	C8—C11—C12—C13	29.3 (3)
F1—C1—C6—C5	−179.18 (17)	C8—C11—C12—C17	−154.43 (17)
C2—C1—C6—C5	−0.1 (3)	C17—C12—C13—C14	0.8 (2)
C4—C5—C6—C1	−0.9 (3)	C11—C12—C13—C14	177.03 (16)
C3—C4—C7—O1	−46.8 (3)	C12—C13—C14—C15	0.8 (3)
C5—C4—C7—O1	126.8 (2)	C13—C14—C15—F3	178.87 (16)
C3—C4—C7—C8	132.36 (19)	C13—C14—C15—C16	−0.9 (3)
C5—C4—C7—C8	−54.0 (2)	F3—C15—C16—C17	179.59 (15)
C9—N1—C8—C11	−116.2 (2)	C14—C15—C16—C17	−0.6 (3)
N2—N1—C8—C11	62.8 (2)	C15—C16—C17—C12	2.3 (3)
C9—N1—C8—C7	60.6 (2)	C13—C12—C17—C16	−2.4 (2)
N2—N1—C8—C7	−120.40 (17)	C11—C12—C17—C16	−178.81 (15)

Experimental details

Crystal data
Chemical formula	C₁₇H₁₀F₃N₃O
M_r	329.28
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	11.735 (6), 7.698 (4), 17.065 (7)
β (°)	110.45 (3)
V (Å³)	1444.4 (12)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.12
Crystal size (mm)	0.19 × 0.17 × 0.16

Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2009)
T_min, T_max	0.977, 0.980
No. of measured, independent and observed [I > 2σ(I)] reflections	7601, 2840, 2095
R_int	0.027
(sin θ/λ)_max (Å⁻¹)	0.617

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.042, 0.100, 1.01
No. of reflections	2840
No. of parameters	217
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.15, −0.21

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Acknowledgements

This work was partially supported by National Natural Science Foundation of China (No. 21172181), the Key Program of the Natural Science Foundation of Chongqing (CSTC2012jjB10026), the Specialized Research Fund for the Doctoral Program of Higher Education of China (SRFDP 20110182110007) and the Research Funds for the Central Universities (XDJK2011D007, XDJK2012B026).

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