1-[2,4-Bis(4-fluoro­phen­oxy)phen­yl]­ethanone

The title compound, C₂₀H₁₄F₂O₃, has been obtained in a search for new fluorine-containing compounds with better biological activity. The two fluoro­phenyl rings are oriented at angles of 64.03 (2) and 64.55 (3)° to the ethanone-substituted benzene ring. The structure is stabilized by C—H...O hydrogen bonds, in addition to van der Waals forces.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.068
• wR factor = 0.198
• Data-to-parameter ratio = 12.3

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT029_ALERT_3_B _diffrn_measured_fraction_theta_full Low .......       0.96

Alert level C
PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical .          ?
PLAT152_ALERT_1_C Supplied and Calc Volume s.u. Inconsistent .....          ?
PLAT154_ALERT_1_C The su's on the Cell Angles are Equal  (x 10000)       3000 Deg.
PLAT241_ALERT_2_C Check High      Ueq as Compared to Neighbors for         O2
PLAT241_ALERT_2_C Check High      Ueq as Compared to Neighbors for         O3
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for        C18

   0 ALERT level A = In general: serious problem
   1 ALERT level B = Potentially serious problem
   6 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   3 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   3 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

Recently, interest in fluorine-containing compounds is continuously growing since fluorinated organic products present unique properties that are of great interest for a variety of applications (Thierry & Bernard, 2002). The title compound (I) was synthesized as a useful intermediate for the synthesis of compounds with better biological activity. We report here the crystal structure of (I).

In (I) (Fig. 1), all bond lengths and angles are normal (Allen et al., 1987) and in a good agreement with those reported previously (Xu et al., 2007)·The two fluorophenyl rings (C9—C14) and (C15—C20) are oriented at angles of 64.03 (2) and 64.55 (3)°, respectively, to the ethanone substituted phenyl ring (C1—C6). The structure is stabilized by hydrogen bonds of C—H···O type, in addition to van der Waals forces.

Related literature

For related literatures see: Allen et al. (1987); Thierry & Bernard (2002); Xu et al. (2007).

S2. Experimental

Acetyl chloride (10 mmol) was added dropwise to a solution of 1,3-bis(4-fluorophenoxy)benzene (10 mmol), aluminium oxide (13 mmol), carbon sulfide (20 ml) and the mixture was heated under reflux for 2 h. Then the mixture was extracted with CS₂ (15 ml) and the organic layer was washed with 50% NaOH solution and water. The excess CS₂ was removed on a water vacuum pump to obtain the final product (80% yield). Single crystals suitable for X-ray measurements were obtained by recrystallization from ethanol at room temperature.

S3. Refinement

All H atoms were placed in calculated positions, with C—H = 0.93 or 0.96 Å, and included in the final cycles of refinement using a riding model, with U_iso(H) = 1.2 (1.5 for methyl groups) times U_eq(C).

Computing details

Data collection: RAPID-AUTO (Rigaku, 2004); cell refinement: RAPID-AUTO (Rigaku, 2004); data reduction: RAPID-AUTO (Rigaku, 2004); program(s) used to solve structure: SHELXTL (Sheldrick, 2001); program(s) used to refine structure: SHELXTL (Sheldrick, 2001); molecular graphics: SHELXTL (Sheldrick, 2001); software used to prepare material for publication: SHELXTL (Sheldrick, 2001).

Figures

	Fig. 1. View of the title compound (I), with displacement ellipsoids drawn at the 40% probability level.
	Fig. 2. A packing diagram of the molecule of the title compound. Hydrogen bonds are shown as dashed lines.

1-[2,4-Bis(4-fluorophenoxy)phenyl]ethanone

Crystal data

C20H14F2O3	Z = 2
Mr = 340.31	F(000) = 352
Triclinic, P1	Dx = 1.361 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 6.746 (2) Å	Cell parameters from 2755 reflections
b = 9.573 (2) Å	θ = 2.4–24.8°
c = 13.335 (3) Å	µ = 0.11 mm^−1
α = 100.52 (3)°	T = 298 K
β = 98.43 (3)°	Block, colorless
γ = 95.68 (3)°	0.30 × 0.20 × 0.18 mm
V = 830.5 (3) Å^3

Data collection

Rigaku R-AXIS RAPID IP area-detector diffractometer	2798 independent reflections
Radiation source: Rotating Anode	2258 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.048
ω scans	θmax = 25.0°, θmin = 2.9°
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	h = −8→8
Tmin = 0.969, Tmax = 0.981	k = −11→10
4425 measured reflections	l = −15→15

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.068	H-atom parameters constrained
wR(F^2) = 0.198	w = 1/[σ^2(Fo^2) + (0.098P)^2 + 0.2416P] where P = (Fo^2 + 2Fc^2)/3
S = 1.11	(Δ/σ)max < 0.001
2798 reflections	Δρmax = 0.21 e Å^−3
228 parameters	Δρmin = −0.22 e Å^−3
0 restraints	Extinction correction: SHELXTL (Sheldrick, 2001), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.062 (10)

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
F1	0.8326 (3)	0.3501 (2)	−0.04283 (15)	0.0936 (7)
F2	1.0613 (4)	0.9902 (3)	0.1086 (2)	0.1280 (10)
O1	0.1919 (3)	0.3955 (2)	0.54241 (14)	0.0695 (6)
O2	0.3463 (3)	0.3970 (2)	0.25339 (14)	0.0720 (6)
O3	0.4744 (4)	0.9133 (2)	0.34425 (18)	0.0815 (7)
C1	0.2820 (3)	0.5192 (3)	0.41566 (18)	0.0503 (6)
C2	0.3478 (4)	0.5248 (3)	0.32182 (18)	0.0515 (6)
C3	0.4082 (4)	0.6547 (3)	0.29566 (19)	0.0564 (7)
H3A	0.4445	0.6565	0.2312	0.068*
C4	0.4139 (4)	0.7808 (3)	0.3659 (2)	0.0595 (7)
C5	0.3509 (4)	0.7798 (3)	0.4596 (2)	0.0663 (8)
H5A	0.3520	0.8650	0.5063	0.080*
C6	0.2867 (4)	0.6510 (3)	0.4826 (2)	0.0605 (7)
H6A	0.2442	0.6509	0.5459	0.073*
C7	0.2111 (3)	0.3868 (3)	0.45263 (19)	0.0552 (7)
C8	0.1539 (6)	0.2446 (4)	0.3795 (3)	0.0796 (9)
H8A	0.0834	0.1786	0.4125	0.119*
H8B	0.2737	0.2079	0.3610	0.119*
H8C	0.0679	0.2563	0.3184	0.119*
C9	0.4752 (4)	0.3906 (3)	0.17958 (19)	0.0542 (7)
C10	0.6793 (5)	0.4384 (3)	0.2068 (2)	0.0611 (7)
H10A	0.7348	0.4790	0.2752	0.073*
C11	0.8014 (5)	0.4251 (3)	0.1309 (2)	0.0648 (7)
H11A	0.9391	0.4576	0.1470	0.078*
C12	0.7127 (5)	0.3626 (3)	0.0316 (2)	0.0610 (7)
C13	0.5120 (5)	0.3126 (3)	0.0045 (2)	0.0629 (7)
H13A	0.4578	0.2693	−0.0636	0.075*
C14	0.3894 (4)	0.3270 (3)	0.07976 (19)	0.0572 (7)
H14A	0.2519	0.2943	0.0629	0.069*
C15	0.6225 (5)	0.9241 (3)	0.2822 (2)	0.0650 (8)
C16	0.7975 (5)	0.8591 (3)	0.2959 (2)	0.0708 (8)
H16A	0.8162	0.8025	0.3454	0.085*
C17	0.9435 (5)	0.8794 (4)	0.2352 (3)	0.0788 (9)
H17A	1.0593	0.8342	0.2414	0.095*
C18	0.9138 (6)	0.9673 (4)	0.1659 (3)	0.0812 (10)
C19	0.7423 (6)	1.0335 (3)	0.1517 (3)	0.0858 (11)
H19A	0.7262	1.0919	0.1033	0.103*
C20	0.5954 (6)	1.0112 (3)	0.2107 (3)	0.0770 (9)
H20A	0.4784	1.0547	0.2025	0.092*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
F1	0.1111 (15)	0.1002 (14)	0.0762 (12)	0.0141 (12)	0.0497 (11)	0.0073 (10)
F2	0.126 (2)	0.146 (2)	0.1240 (19)	−0.0163 (17)	0.0406 (16)	0.0590 (17)
O1	0.0619 (12)	0.0960 (15)	0.0501 (11)	−0.0013 (10)	0.0122 (9)	0.0167 (10)
O2	0.1009 (15)	0.0544 (11)	0.0554 (11)	−0.0125 (10)	0.0350 (11)	−0.0076 (9)
O3	0.1117 (18)	0.0508 (11)	0.0873 (15)	0.0160 (11)	0.0374 (13)	0.0076 (10)
C1	0.0400 (12)	0.0630 (15)	0.0437 (13)	0.0040 (11)	0.0045 (9)	0.0029 (11)
C2	0.0526 (13)	0.0534 (14)	0.0437 (13)	0.0027 (11)	0.0074 (10)	0.0003 (10)
C3	0.0668 (16)	0.0562 (15)	0.0453 (13)	0.0082 (12)	0.0114 (11)	0.0061 (11)
C4	0.0660 (16)	0.0512 (14)	0.0591 (16)	0.0091 (12)	0.0098 (12)	0.0050 (12)
C5	0.0694 (17)	0.0626 (17)	0.0623 (17)	0.0104 (14)	0.0189 (14)	−0.0069 (13)
C6	0.0534 (15)	0.0759 (18)	0.0490 (14)	0.0067 (13)	0.0156 (11)	−0.0006 (13)
C7	0.0398 (12)	0.0766 (17)	0.0469 (14)	−0.0005 (12)	0.0065 (10)	0.0115 (12)
C8	0.092 (2)	0.0726 (19)	0.0683 (18)	−0.0170 (17)	0.0211 (16)	0.0073 (15)
C9	0.0776 (18)	0.0418 (12)	0.0442 (13)	0.0043 (12)	0.0200 (12)	0.0052 (10)
C10	0.0772 (18)	0.0581 (15)	0.0436 (13)	0.0074 (14)	0.0055 (12)	0.0030 (11)
C11	0.0667 (17)	0.0605 (16)	0.0672 (17)	0.0096 (13)	0.0137 (14)	0.0099 (13)
C12	0.084 (2)	0.0541 (15)	0.0503 (15)	0.0157 (14)	0.0269 (14)	0.0090 (12)
C13	0.090 (2)	0.0548 (15)	0.0398 (13)	0.0043 (14)	0.0112 (13)	0.0005 (11)
C14	0.0724 (17)	0.0460 (13)	0.0495 (14)	0.0006 (12)	0.0097 (12)	0.0045 (11)
C15	0.089 (2)	0.0406 (13)	0.0598 (16)	−0.0016 (14)	0.0094 (14)	0.0027 (12)
C16	0.087 (2)	0.0630 (17)	0.0603 (17)	−0.0003 (16)	0.0029 (15)	0.0208 (13)
C17	0.0735 (19)	0.079 (2)	0.083 (2)	−0.0035 (16)	0.0030 (16)	0.0288 (17)
C18	0.094 (2)	0.073 (2)	0.072 (2)	−0.0183 (19)	0.0111 (17)	0.0231 (16)
C19	0.120 (3)	0.0581 (18)	0.077 (2)	−0.0054 (19)	0.004 (2)	0.0274 (16)
C20	0.101 (2)	0.0448 (15)	0.083 (2)	0.0085 (15)	0.0073 (18)	0.0136 (14)

Geometric parameters (Å, º)

F1—C12	1.365 (3)	C9—C14	1.373 (4)
F2—C18	1.366 (4)	C9—C10	1.380 (4)
O1—C7	1.212 (3)	C10—C11	1.392 (4)
O2—C2	1.384 (3)	C10—H10A	0.9300
O2—C9	1.403 (3)	C11—C12	1.370 (4)
O3—C4	1.388 (3)	C11—H11A	0.9300
O3—C15	1.395 (4)	C12—C13	1.363 (4)
C1—C2	1.396 (3)	C13—C14	1.387 (4)
C1—C6	1.401 (4)	C13—H13A	0.9300
C1—C7	1.502 (4)	C14—H14A	0.9300
C2—C3	1.391 (4)	C15—C20	1.381 (4)
C3—C4	1.380 (4)	C15—C16	1.392 (5)
C3—H3A	0.9300	C16—C17	1.385 (4)
C4—C5	1.379 (4)	C16—H16A	0.9300
C5—C6	1.369 (4)	C17—C18	1.365 (5)
C5—H5A	0.9300	C17—H17A	0.9300
C6—H6A	0.9300	C18—C19	1.378 (5)
C7—C8	1.501 (4)	C19—C20	1.376 (5)
C8—H8A	0.9600	C19—H19A	0.9300
C8—H8B	0.9600	C20—H20A	0.9300
C8—H8C	0.9600
C2—O2—C9	119.45 (19)	C9—C10—H10A	120.3
C4—O3—C15	118.9 (2)	C11—C10—H10A	120.3
C2—C1—C6	116.3 (2)	C12—C11—C10	118.0 (3)
C2—C1—C7	126.7 (2)	C12—C11—H11A	121.0
C6—C1—C7	117.0 (2)	C10—C11—H11A	121.0
O2—C2—C3	120.4 (2)	C13—C12—F1	119.1 (2)
O2—C2—C1	118.2 (2)	C13—C12—C11	123.0 (3)
C3—C2—C1	121.4 (2)	F1—C12—C11	117.9 (3)
C4—C3—C2	119.6 (2)	C12—C13—C14	119.2 (2)
C4—C3—H3A	120.2	C12—C13—H13A	120.4
C2—C3—H3A	120.2	C14—C13—H13A	120.4
C5—C4—C3	120.7 (3)	C9—C14—C13	118.7 (3)
C5—C4—O3	117.2 (2)	C9—C14—H14A	120.7
C3—C4—O3	122.0 (2)	C13—C14—H14A	120.7
C6—C5—C4	118.7 (2)	C20—C15—C16	120.8 (3)
C6—C5—H5A	120.6	C20—C15—O3	117.0 (3)
C4—C5—H5A	120.6	C16—C15—O3	122.1 (3)
C5—C6—C1	123.3 (2)	C17—C16—C15	119.4 (3)
C5—C6—H6A	118.4	C17—C16—H16A	120.3
C1—C6—H6A	118.4	C15—C16—H16A	120.3
O1—C7—C8	119.0 (3)	C18—C17—C16	118.5 (3)
O1—C7—C1	119.5 (2)	C18—C17—H17A	120.7
C8—C7—C1	121.4 (2)	C16—C17—H17A	120.7
C7—C8—H8A	109.5	C17—C18—F2	118.1 (4)
C7—C8—H8B	109.5	C17—C18—C19	122.9 (3)
H8A—C8—H8B	109.5	F2—C18—C19	119.0 (3)
C7—C8—H8C	109.5	C20—C19—C18	118.6 (3)
H8A—C8—H8C	109.5	C20—C19—H19A	120.7
H8B—C8—H8C	109.5	C18—C19—H19A	120.7
C14—C9—C10	121.8 (2)	C19—C20—C15	119.7 (3)
C14—C9—O2	116.4 (2)	C19—C20—H20A	120.1
C10—C9—O2	121.8 (2)	C15—C20—H20A	120.1
C9—C10—C11	119.3 (2)
C9—O2—C2—C3	25.4 (4)	C14—C9—C10—C11	1.6 (4)
C9—O2—C2—C1	−156.4 (2)	O2—C9—C10—C11	177.9 (2)
C6—C1—C2—O2	179.8 (2)	C9—C10—C11—C12	−0.9 (4)
C7—C1—C2—O2	1.1 (4)	C10—C11—C12—C13	−0.4 (4)
C6—C1—C2—C3	−2.0 (4)	C10—C11—C12—F1	179.8 (2)
C7—C1—C2—C3	179.3 (2)	F1—C12—C13—C14	−179.1 (2)
O2—C2—C3—C4	−178.3 (2)	C11—C12—C13—C14	1.1 (4)
C1—C2—C3—C4	3.5 (4)	C10—C9—C14—C13	−0.9 (4)
C2—C3—C4—C5	−3.2 (4)	O2—C9—C14—C13	−177.4 (2)
C2—C3—C4—O3	179.5 (3)	C12—C13—C14—C9	−0.4 (4)
C15—O3—C4—C5	149.4 (3)	C4—O3—C15—C20	139.8 (3)
C15—O3—C4—C3	−33.2 (4)	C4—O3—C15—C16	−44.8 (4)
C3—C4—C5—C6	1.4 (4)	C20—C15—C16—C17	−1.7 (4)
O3—C4—C5—C6	178.9 (3)	O3—C15—C16—C17	−176.9 (3)
C4—C5—C6—C1	0.1 (4)	C15—C16—C17—C18	2.3 (5)
C2—C1—C6—C5	0.2 (4)	C16—C17—C18—F2	178.0 (3)
C7—C1—C6—C5	179.0 (3)	C16—C17—C18—C19	−1.9 (5)
C2—C1—C7—O1	167.1 (2)	C17—C18—C19—C20	0.7 (5)
C6—C1—C7—O1	−11.5 (4)	F2—C18—C19—C20	−179.2 (3)
C2—C1—C7—C8	−15.8 (4)	C18—C19—C20—C15	0.0 (5)
C6—C1—C7—C8	165.5 (3)	C16—C15—C20—C19	0.5 (4)
C2—O2—C9—C14	−132.5 (3)	O3—C15—C20—C19	175.9 (3)
C2—O2—C9—C10	51.0 (4)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C10—H10A···O1^i	0.93	2.46	3.376 (3)	167

Symmetry code: (i) −x+1, −y+1, −z+1.