2-Amino-3,4,5,6-tetra­fluoro­benzoic acid

Liao, X.-J.; Guo, W.; Xu, S.-H.

doi:10.1107/S1600536811023087

organic compounds

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ISSN: 2056-9890

Volume 67| Part 7| July 2011| Page o1732

doi:10.1107/S1600536811023087

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2-Amino-3,4,5,6-tetrafluorobenzoic acid

Xiao-Jian Liao,^a Wei Guo ^a and Shi-Hai Xu ^a ^*

^aDepartment of Chemistry, Jinan University, Guangzhou 510632, People's Republic of China
^*Correspondence e-mail: txush@jnu.edu.cn

(Received 23 May 2011; accepted 14 June 2011; online 18 June 2011)

The asymmetric unit of the title compound, C₇H₃F₄NO₂, obtained as an intermediate in the synthesis of a coupling reagent, contains four independent and conformationally similar molecules. The amine H atoms form both intramolecular and intermolecular N—H⋯O_carboxyl hydrogen bonds which, together with intermolecular O—H⋯O_carboxyl hydrogen bonds and N—H⋯F associations form ribbon structures along the a axis.

Related literature

The title compound was obtained as one of the intermediates in the synthesis of a coupling reagent (Xu et al., 2008 ; Liao et al., 2007 ), using the Hofmann rearrangement (Perumal & Muthialu, 2004 ) with 2-carboxyl-3,4,5,6-tetrafluorobenzamide (Cai et al., 1992 ).

Experimental

Crystal data

C₇H₃F₄NO₂
M_r = 209.10
Triclinic, $[P \overline 1]$
a = 11.0367 (11) Å
b = 11.3664 (11) Å
c = 12.5702 (12) Å
α = 80.378 (8)°
β = 79.764 (8)°
γ = 82.011 (8)°
V = 1520.2 (3) Å³
Z = 8
Cu Kα radiation
μ = 1.79 mm⁻¹
T = 295 K
0.50 × 0.30 × 0.15 mm

Data collection

Oxford Diffraction Xcalibur Sapphire3 Gemini ultra CCD diffractometer
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2010 $[Oxford Diffraction (2010). CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, England.]$ ) T_min = 0.392, T_max = 1.000
8708 measured reflections
4791 independent reflections
3521 reflections with I > 2σ(I)
R_int = 0.031

Refinement

R[F² > 2σ(F²)] = 0.057
wR(F²) = 0.177
S = 1.05
4791 reflections
533 parameters
16 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.43 e Å⁻³
Δρ_min = −0.24 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1B⋯O4	0.84 (3)	2.04 (4)	2.637 (4)	128 (3)
N1—H1B⋯F5ⁱ	0.84 (3)	2.40 (3)	3.154 (4)	150 (3)
N2—H2A⋯O10ⁱⁱ	0.83 (3)	2.58 (3)	3.363 (5)	158 (3)
N2—H2B⋯O7	0.85 (3)	2.03 (4)	2.643 (5)	129 (3)
N3—H3A⋯O11ⁱⁱⁱ	0.85 (3)	2.50 (3)	3.337 (4)	167 (3)
N3—H3B⋯O5	0.85 (3)	2.04 (4)	2.654 (4)	129 (3)
N4—H4B⋯O1	0.86 (3)	2.01 (3)	2.648 (4)	130 (3)
N4—H4B⋯F16^iv	0.86 (3)	2.48 (3)	3.191 (5)	140 (3)
O9—H9⋯O5^v	0.82	1.84	2.660 (3)	175
O10—H10⋯O4^vi	0.82	1.86	2.675 (4)	178
O11—H11⋯O1^vi	0.82	1.82	2.643 (3)	177
Symmetry codes: (i) -x+1, -y+1, -z+2; (ii) x, y-1, z+1; (iii) x, y-1, z; (iv) -x+1, -y+1, -z+1; (v) -x, -y, -z+1; (vi) -x+1, -y+2, -z+1.

Data collection: CrysAlis PRO (Oxford Diffraction, 2010 $[Oxford Diffraction (2010). CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, England.]$ ); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009 ); software used to prepare material for publication: OLEX2.

Supporting information

Crystal structure: contains datablock global. DOI: 10.1107/S1600536811023087/zs2117sup1.cif

Supporting information file. DOI: 10.1107/S1600536811023087/zs2117globalsup2.cml

checkCIF report

Comment top

The title compound C₇H₃F₄NO₂ (I) was obtained as one of the intermediates in the synthesis of a coupling reagent (Xu et al., 2008, Liao et al., 2007), using the Hofmann rearrangement (Perumal & Muthialu, 2004) with 2-carboxyl-3,4,5,6-tetrafluorobenzamide (Cai et al., 1992). In the structure of (I), the asymmetric unit contains four independent and conformationally similar molecules (Fig. 1). The molecules associate through carboxylic acid O—H···O_carboxyl hydrogen bonds (Table 1) while the amine H atoms form both intramolecular N—H···O_carboxyl hydrogen bonds as well as intermolecular N—H···F associations give one-dimensional ribbon structures. Also present in the structure are short intermolecular F···F contacts [minimum, 2.825 (3) Å].

Related literature top

The title compound was obtained as one of the intermediates in the synthesis of a coupling reagent (Xu et al., 2008; Liao et al., 2007), using the Hofmann rearrangement (Perumal & Muthialu, 2004) with 2-carboxyl-3,4,5,6-tetrafluorobenzamide (Cai et al., 1992).

Experimental top

To a stirred solution of 39.2 g of KOH in 356 mL of distilled water, 11.3 g of bromine was added and after 30 min, 70 mmol of 2-carboxy-3,4,5,6-tetrafluorobenzamide was added. After allowing the reaction to proceed for 30 min at 293 K, the mixture was heated to 363K-368K and maintained at that temperature for 4 h, after which the mixture was cooled to room temperature and allowed to stand for 48 h. To the mixture was then added 100 mL of water, the pH adjusted to 1 at ice-water temperature, stirred and filtered, giving a yellow solid (16.2 g, yield 94%). Pale yellow crystals of (I) suitable for X-ray analysis grew over a period of a week from a solution of the solid in methanol at room temperature.

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2010); cell refinement: CrysAlis PRO (Oxford Diffraction, 2010); data reduction: CrysAlis PRO (Oxford Diffraction, 2010); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

Figures top

Fig. 1. The molecular conformation of the four independent molecules in the asymmetric unit of the title compound, showing the atom numbering scheme. Intramolecular hydrogen bonds are shown as dashed lines. Displacement ellipsoids are drawn at the 50% probability level.

2-Amino-3,4,5,6-tetrafluorobenzoic acid top

Crystal data top

C₇H₃F₄NO₂	Z = 8
M_r = 209.10	F(000) = 832
Triclinic, P1	D_x = 1.827 Mg m⁻³
a = 11.0367 (11) Å	Cu Kα radiation, λ = 1.5418 Å
b = 11.3664 (11) Å	Cell parameters from 4167 reflections
c = 12.5702 (12) Å	θ = 3.6–62.7°
α = 80.378 (8)°	µ = 1.79 mm⁻¹
β = 79.764 (8)°	T = 295 K
γ = 82.011 (8)°	Plate, pale yellow
V = 1520.2 (3) Å³	0.50 × 0.30 × 0.15 mm

Data collection top

Oxford Diffraction Xcalibur Sapphire3 Gemini ultra CCD diffractometer	4791 independent reflections
Radiation source: Enhance Ultra (Cu) X-ray Source	3521 reflections with I > 2σ(I)
Mirror monochromator	R_int = 0.031
Detector resolution: 16.0288 pixels mm^-1	θ_max = 62.8°, θ_min = 3.6°
ω scans	h = −12→12
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2010)	k = −12→13
T_min = 0.392, T_max = 1.000	l = −14→14
8708 measured reflections

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)] = 0.057	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.177	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	w = 1/[σ²(F_o²) + (0.0935P)² + 0.6844P] where P = (F_o² + 2F_c²)/3
4791 reflections	(Δ/σ)_max < 0.001
533 parameters	Δρ_max = 0.43 e Å⁻³
16 restraints	Δρ_min = −0.24 e Å⁻³

Crystal data top

C₇H₃F₄NO₂	γ = 82.011 (8)°
M_r = 209.10	V = 1520.2 (3) Å³
Triclinic, P1	Z = 8
a = 11.0367 (11) Å	Cu Kα radiation
b = 11.3664 (11) Å	µ = 1.79 mm⁻¹
c = 12.5702 (12) Å	T = 295 K
α = 80.378 (8)°	0.50 × 0.30 × 0.15 mm
β = 79.764 (8)°

Data collection top

Oxford Diffraction Xcalibur Sapphire3 Gemini ultra CCD diffractometer	4791 independent reflections
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2010)	3521 reflections with I > 2σ(I)
T_min = 0.392, T_max = 1.000	R_int = 0.031
8708 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.057	16 restraints
wR(F²) = 0.177	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	Δρ_max = 0.43 e Å⁻³
4791 reflections	Δρ_min = −0.24 e Å⁻³
533 parameters

Special details top

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) top

	x	y	z	U_iso*/U_eq
F16	0.18790 (19)	0.2980 (2)	0.63873 (16)	0.0672 (6)
F13	−0.0401 (2)	0.42992 (19)	0.28267 (16)	0.0682 (6)
F14	0.1447 (2)	0.54588 (19)	0.30496 (17)	0.0701 (6)
O8	−0.1849 (2)	0.2707 (2)	0.3563 (2)	0.0632 (7)
H8	−0.2349	0.2248	0.3531	0.095*
F15	0.2604 (2)	0.4812 (2)	0.48248 (19)	0.0747 (6)
O5	−0.1389 (2)	0.1291 (2)	0.49241 (19)	0.0622 (7)
C22	0.0365 (3)	0.2621 (3)	0.5411 (2)	0.0441 (7)
N3	0.0065 (3)	0.1737 (3)	0.6245 (2)	0.0581 (8)
C32	0.1097 (3)	0.4535 (3)	0.3810 (3)	0.0502 (8)
C33	−0.1201 (3)	0.2250 (3)	0.4350 (2)	0.0470 (7)
C34	−0.0239 (3)	0.2952 (3)	0.4488 (2)	0.0443 (7)
C37	0.0151 (3)	0.3923 (3)	0.3714 (2)	0.0456 (7)
C42	0.1311 (3)	0.3284 (3)	0.5489 (3)	0.0491 (8)
C51	0.1684 (3)	0.4208 (3)	0.4715 (3)	0.0524 (8)
F8	0.3963 (2)	0.21194 (19)	0.48315 (16)	0.0667 (6)
O9	0.2802 (2)	0.0302 (2)	0.5375 (2)	0.0615 (6)
H9	0.2341	−0.0183	0.5317	0.092*
O7	0.3410 (2)	−0.1190 (2)	0.6616 (2)	0.0627 (7)
F5	0.6708 (2)	0.0512 (2)	0.8060 (2)	0.0892 (8)
F6	0.6953 (2)	0.2663 (2)	0.6819 (2)	0.0787 (7)
F7	0.5568 (2)	0.3471 (2)	0.5210 (2)	0.0827 (7)
C28	0.4414 (3)	0.0572 (3)	0.6287 (2)	0.0462 (7)
C35	0.5150 (3)	0.0154 (3)	0.7126 (3)	0.0531 (8)
C40	0.5419 (3)	0.2401 (3)	0.5830 (3)	0.0577 (9)
C44	0.5992 (3)	0.0896 (3)	0.7262 (3)	0.0601 (9)
C47	0.3507 (3)	−0.0174 (3)	0.6118 (2)	0.0469 (7)
C49	0.4586 (3)	0.1696 (3)	0.5659 (3)	0.0498 (8)
N2	0.5075 (4)	−0.0899 (3)	0.7795 (3)	0.0833 (12)
C56	0.6129 (3)	0.1984 (3)	0.6649 (3)	0.0583 (9)
F4	0.0302 (2)	0.94676 (19)	0.75391 (15)	0.0700 (6)
O11	0.1722 (2)	1.0628 (2)	0.82373 (17)	0.0570 (6)
H11	0.2109	1.1185	0.8268	0.085*
O4	0.2335 (2)	0.9962 (2)	0.98460 (19)	0.0594 (6)
F3	−0.1220 (2)	0.7811 (2)	0.78819 (17)	0.0745 (6)
F2	−0.1394 (2)	0.6232 (2)	0.97776 (19)	0.0815 (7)
F1	−0.0109 (2)	0.6443 (2)	1.13507 (17)	0.0810 (7)
N1	0.1387 (3)	0.8133 (3)	1.1147 (2)	0.0620 (8)
C29	0.0014 (3)	0.7205 (3)	1.0410 (3)	0.0543 (8)
C31	0.0926 (3)	0.8903 (3)	0.9301 (2)	0.0432 (7)
C36	0.0799 (3)	0.8091 (3)	1.0291 (2)	0.0471 (7)
C39	−0.0549 (3)	0.7890 (3)	0.8658 (3)	0.0544 (8)
C41	−0.0645 (3)	0.7095 (3)	0.9618 (3)	0.0565 (9)
C43	0.0231 (3)	0.8750 (3)	0.8509 (2)	0.0473 (7)
C46	0.1720 (3)	0.9855 (3)	0.9152 (2)	0.0464 (7)
F12	0.4204 (2)	0.75684 (19)	−0.01077 (18)	0.0705 (6)
F11	0.2839 (2)	0.5761 (2)	0.0206 (2)	0.0766 (7)
O10	0.6074 (3)	0.8442 (2)	0.0225 (2)	0.0687 (7)
H10	0.6552	0.8943	0.0195	0.103*
O1	0.6965 (2)	0.7627 (2)	0.1668 (2)	0.0632 (7)
C26	0.5475 (3)	0.6595 (3)	0.1206 (2)	0.0451 (7)
F10	0.3353 (2)	0.3778 (2)	0.1668 (2)	0.0847 (7)
F9	0.5247 (3)	0.3629 (2)	0.2782 (2)	0.1045 (10)
C38	0.4484 (3)	0.6618 (3)	0.0631 (3)	0.0487 (8)
N4	0.6652 (4)	0.5390 (3)	0.2570 (3)	0.0928 (14)
C48	0.3770 (3)	0.5711 (3)	0.0787 (3)	0.0544 (8)
C50	0.6226 (3)	0.7589 (3)	0.1051 (3)	0.0497 (8)
C53	0.5726 (4)	0.5559 (3)	0.1963 (3)	0.0582 (9)
C54	0.4979 (4)	0.4638 (3)	0.2087 (3)	0.0660 (10)
C55	0.4029 (4)	0.4695 (3)	0.1527 (3)	0.0597 (9)
H3A	0.059 (3)	0.147 (3)	0.667 (2)	0.072*
H3B	−0.039 (3)	0.123 (3)	0.615 (3)	0.072*
H2A	0.551 (3)	−0.113 (3)	0.828 (2)	0.100*
H2B	0.463 (3)	−0.140 (2)	0.768 (3)	0.100*
H1A	0.129 (3)	0.760 (3)	1.1720 (19)	0.074*
H1B	0.186 (3)	0.866 (3)	1.112 (3)	0.074*
H4A	0.681 (3)	0.476 (2)	0.299 (3)	0.107*
H4B	0.713 (3)	0.595 (2)	0.249 (3)	0.107*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
F16	0.0711 (13)	0.0830 (14)	0.0560 (11)	−0.0196 (11)	−0.0327 (10)	−0.0008 (10)
F13	0.0819 (14)	0.0688 (13)	0.0578 (11)	−0.0236 (11)	−0.0350 (10)	0.0176 (10)
F14	0.0769 (14)	0.0623 (13)	0.0693 (13)	−0.0277 (11)	−0.0150 (11)	0.0155 (10)
O8	0.0711 (16)	0.0587 (15)	0.0679 (15)	−0.0207 (12)	−0.0400 (13)	0.0094 (12)
F15	0.0702 (14)	0.0751 (14)	0.0891 (15)	−0.0329 (11)	−0.0289 (11)	−0.0035 (12)
O5	0.0732 (16)	0.0615 (15)	0.0586 (14)	−0.0300 (13)	−0.0300 (12)	0.0119 (12)
C22	0.0460 (17)	0.0459 (17)	0.0392 (15)	−0.0039 (14)	−0.0091 (13)	−0.0018 (13)
N3	0.0614 (18)	0.0679 (19)	0.0467 (15)	−0.0201 (15)	−0.0227 (13)	0.0121 (14)
C32	0.0527 (19)	0.0426 (17)	0.0533 (18)	−0.0106 (15)	−0.0077 (15)	0.0028 (15)
C33	0.0510 (18)	0.0487 (18)	0.0421 (16)	−0.0080 (15)	−0.0120 (14)	−0.0019 (14)
C34	0.0477 (17)	0.0444 (17)	0.0414 (15)	−0.0077 (14)	−0.0125 (13)	0.0001 (13)
C37	0.0526 (18)	0.0442 (17)	0.0402 (16)	−0.0077 (14)	−0.0163 (13)	0.0046 (13)
C42	0.0504 (18)	0.0532 (19)	0.0455 (16)	−0.0057 (15)	−0.0171 (14)	−0.0023 (15)
C51	0.0479 (18)	0.055 (2)	0.0574 (19)	−0.0131 (15)	−0.0134 (15)	−0.0069 (16)
F8	0.0722 (13)	0.0644 (13)	0.0647 (12)	−0.0157 (10)	−0.0253 (10)	0.0096 (10)
O9	0.0639 (15)	0.0617 (15)	0.0664 (15)	−0.0199 (12)	−0.0318 (12)	0.0028 (12)
O7	0.0704 (16)	0.0519 (14)	0.0726 (15)	−0.0180 (12)	−0.0341 (13)	0.0049 (12)
F5	0.0981 (18)	0.0973 (18)	0.0898 (16)	−0.0335 (14)	−0.0588 (14)	0.0020 (14)
F6	0.0734 (14)	0.0865 (16)	0.0894 (15)	−0.0374 (12)	−0.0187 (12)	−0.0206 (13)
F7	0.0925 (17)	0.0697 (14)	0.0882 (16)	−0.0367 (13)	−0.0184 (13)	0.0091 (12)
C28	0.0464 (17)	0.0485 (18)	0.0459 (17)	−0.0093 (14)	−0.0086 (14)	−0.0083 (14)
C35	0.059 (2)	0.054 (2)	0.0506 (18)	−0.0128 (16)	−0.0177 (15)	−0.0036 (15)
C40	0.062 (2)	0.052 (2)	0.060 (2)	−0.0190 (17)	−0.0034 (17)	−0.0053 (16)
C44	0.064 (2)	0.068 (2)	0.056 (2)	−0.0163 (19)	−0.0233 (17)	−0.0101 (18)
C47	0.0461 (17)	0.0507 (19)	0.0457 (16)	−0.0047 (14)	−0.0126 (13)	−0.0069 (15)
C49	0.0493 (18)	0.056 (2)	0.0443 (16)	−0.0094 (15)	−0.0093 (14)	−0.0033 (15)
N2	0.108 (3)	0.072 (2)	0.084 (2)	−0.037 (2)	−0.061 (2)	0.0190 (19)
C56	0.055 (2)	0.066 (2)	0.060 (2)	−0.0208 (17)	−0.0073 (16)	−0.0166 (18)
F4	0.1041 (17)	0.0657 (13)	0.0480 (11)	−0.0320 (12)	−0.0316 (11)	0.0086 (9)
O11	0.0755 (16)	0.0548 (14)	0.0449 (12)	−0.0271 (12)	−0.0167 (11)	0.0045 (10)
O4	0.0715 (16)	0.0568 (14)	0.0564 (13)	−0.0259 (12)	−0.0274 (12)	0.0074 (11)
F3	0.0953 (16)	0.0776 (14)	0.0655 (13)	−0.0313 (12)	−0.0364 (12)	−0.0099 (11)
F2	0.0936 (17)	0.0807 (15)	0.0808 (15)	−0.0517 (13)	−0.0238 (12)	0.0036 (12)
F1	0.0971 (17)	0.0848 (16)	0.0630 (13)	−0.0440 (13)	−0.0275 (12)	0.0279 (12)
N1	0.069 (2)	0.077 (2)	0.0442 (15)	−0.0264 (16)	−0.0210 (14)	0.0075 (15)
C29	0.059 (2)	0.058 (2)	0.0457 (17)	−0.0195 (17)	−0.0085 (15)	0.0060 (15)
C31	0.0484 (17)	0.0452 (17)	0.0376 (15)	−0.0105 (14)	−0.0079 (13)	−0.0051 (13)
C36	0.0507 (18)	0.0489 (18)	0.0426 (16)	−0.0084 (15)	−0.0100 (13)	−0.0043 (14)
C39	0.063 (2)	0.060 (2)	0.0478 (18)	−0.0139 (17)	−0.0203 (15)	−0.0117 (16)
C41	0.061 (2)	0.053 (2)	0.059 (2)	−0.0229 (17)	−0.0120 (16)	−0.0037 (16)
C43	0.061 (2)	0.0457 (17)	0.0366 (15)	−0.0092 (15)	−0.0140 (14)	−0.0014 (13)
C46	0.0519 (18)	0.0437 (17)	0.0436 (16)	−0.0070 (14)	−0.0087 (14)	−0.0043 (14)
F12	0.0690 (13)	0.0618 (13)	0.0836 (14)	−0.0162 (10)	−0.0357 (11)	0.0138 (11)
F11	0.0623 (13)	0.0722 (14)	0.1048 (17)	−0.0188 (11)	−0.0332 (12)	−0.0095 (13)
O10	0.0822 (18)	0.0604 (15)	0.0701 (16)	−0.0318 (13)	−0.0379 (14)	0.0190 (13)
O1	0.0750 (16)	0.0601 (15)	0.0614 (14)	−0.0257 (13)	−0.0317 (13)	0.0084 (12)
C26	0.0489 (17)	0.0449 (17)	0.0435 (16)	−0.0083 (14)	−0.0119 (13)	−0.0044 (14)
F10	0.0967 (18)	0.0647 (14)	0.1022 (17)	−0.0426 (13)	−0.0251 (14)	−0.0014 (13)
F9	0.155 (3)	0.0682 (15)	0.1023 (19)	−0.0487 (17)	−0.0663 (18)	0.0320 (14)
C38	0.0496 (18)	0.0476 (18)	0.0487 (17)	−0.0077 (15)	−0.0109 (14)	−0.0010 (14)
N4	0.129 (3)	0.061 (2)	0.105 (3)	−0.040 (2)	−0.079 (3)	0.028 (2)
C48	0.0472 (19)	0.059 (2)	0.062 (2)	−0.0116 (16)	−0.0123 (15)	−0.0159 (17)
C50	0.0506 (18)	0.0513 (19)	0.0488 (17)	−0.0112 (15)	−0.0113 (14)	−0.0038 (15)
C53	0.070 (2)	0.056 (2)	0.0538 (19)	−0.0184 (18)	−0.0208 (17)	−0.0015 (16)
C54	0.094 (3)	0.049 (2)	0.058 (2)	−0.023 (2)	−0.0221 (19)	0.0061 (17)
C55	0.068 (2)	0.051 (2)	0.064 (2)	−0.0235 (17)	−0.0069 (18)	−0.0102 (17)

Geometric parameters (Å, º) top

F16—C42	1.360 (3)	F4—C43	1.345 (3)
F13—C37	1.344 (3)	O11—H11	0.8200
F14—C32	1.346 (4)	O11—C46	1.325 (4)
O8—H8	0.8200	O4—C46	1.227 (4)
O8—C33	1.318 (4)	F3—C39	1.346 (4)
F15—C51	1.341 (4)	F2—C41	1.337 (4)
O5—C33	1.224 (4)	F1—C29	1.341 (4)
C22—N3	1.354 (4)	N1—C36	1.362 (4)
C22—C34	1.412 (4)	N1—H1A	0.859 (17)
C22—C42	1.396 (5)	N1—H1B	0.846 (17)
N3—H3A	0.855 (17)	C29—C36	1.390 (5)
N3—H3B	0.854 (17)	C29—C41	1.364 (5)
C32—C37	1.365 (5)	C31—C36	1.417 (4)
C32—C51	1.381 (5)	C31—C43	1.406 (4)
C33—C34	1.463 (4)	C31—C46	1.454 (4)
C34—C37	1.405 (4)	C39—C41	1.379 (5)
C42—C51	1.361 (5)	C39—C43	1.360 (5)
F8—C49	1.335 (4)	F12—C38	1.341 (4)
O9—H9	0.8200	F11—C48	1.353 (4)
O9—C47	1.320 (4)	O10—H10	0.8200
O7—C47	1.228 (4)	O10—C50	1.314 (4)
F5—C44	1.363 (4)	O1—C50	1.229 (4)
F6—C56	1.337 (4)	C26—C38	1.410 (5)
F7—C40	1.344 (4)	C26—C50	1.460 (4)
C28—C35	1.424 (4)	C26—C53	1.413 (5)
C28—C47	1.462 (4)	F10—C55	1.334 (4)
C28—C49	1.403 (5)	F9—C54	1.353 (4)
C35—C44	1.388 (5)	C38—C48	1.351 (5)
C35—N2	1.347 (5)	N4—C53	1.356 (5)
C40—C49	1.367 (5)	N4—H4A	0.827 (17)
C40—C56	1.385 (5)	N4—H4B	0.869 (17)
C44—C56	1.356 (5)	C48—C55	1.388 (5)
N2—H2A	0.829 (17)	C53—C54	1.393 (5)
N2—H2B	0.851 (17)	C54—C55	1.352 (5)

C33—O8—H8	109.5	C46—O11—H11	109.5
N3—C22—C34	124.9 (3)	C36—N1—H1A	120 (2)
N3—C22—C42	117.6 (3)	C36—N1—H1B	121 (2)
C42—C22—C34	117.4 (3)	H1A—N1—H1B	119 (3)
C22—N3—H3A	118 (2)	F1—C29—C36	118.3 (3)
C22—N3—H3B	119 (2)	F1—C29—C41	119.1 (3)
H3A—N3—H3B	115 (3)	C41—C29—C36	122.6 (3)
F14—C32—C37	121.1 (3)	C36—C31—C46	120.2 (3)
F14—C32—C51	119.9 (3)	C43—C31—C36	116.8 (3)
C37—C32—C51	119.0 (3)	C43—C31—C46	123.0 (3)
O8—C33—C34	116.0 (3)	N1—C36—C29	117.5 (3)
O5—C33—O8	121.8 (3)	N1—C36—C31	124.0 (3)
O5—C33—C34	122.2 (3)	C29—C36—C31	118.5 (3)
C22—C34—C33	119.3 (3)	F3—C39—C41	120.3 (3)
C37—C34—C22	117.9 (3)	F3—C39—C43	120.7 (3)
C37—C34—C33	122.7 (3)	C43—C39—C41	119.0 (3)
F13—C37—C32	116.2 (3)	F2—C41—C29	120.2 (3)
F13—C37—C34	121.0 (3)	F2—C41—C39	120.1 (3)
C32—C37—C34	122.8 (3)	C29—C41—C39	119.7 (3)
F16—C42—C22	117.5 (3)	F4—C43—C31	121.1 (3)
F16—C42—C51	119.2 (3)	F4—C43—C39	115.5 (3)
C51—C42—C22	123.3 (3)	C39—C43—C31	123.4 (3)
F15—C51—C32	119.5 (3)	O11—C46—C31	116.6 (3)
F15—C51—C42	121.0 (3)	O4—C46—O11	121.3 (3)
C42—C51—C32	119.5 (3)	O4—C46—C31	122.0 (3)
C47—O9—H9	109.5	C50—O10—H10	109.5
C35—C28—C47	119.2 (3)	C38—C26—C50	122.7 (3)
C49—C28—C35	118.2 (3)	C38—C26—C53	117.4 (3)
C49—C28—C47	122.6 (3)	C53—C26—C50	119.9 (3)
C44—C35—C28	117.2 (3)	F12—C38—C26	120.4 (3)
N2—C35—C28	124.5 (3)	F12—C38—C48	116.6 (3)
N2—C35—C44	118.3 (3)	C48—C38—C26	123.0 (3)
F7—C40—C49	121.2 (3)	C53—N4—H4A	123 (2)
F7—C40—C56	120.2 (3)	C53—N4—H4B	118 (2)
C49—C40—C56	118.6 (3)	H4A—N4—H4B	118 (3)
F5—C44—C35	118.1 (3)	F11—C48—C55	119.7 (3)
C56—C44—F5	118.6 (3)	C38—C48—F11	121.1 (3)
C56—C44—C35	123.3 (3)	C38—C48—C55	119.2 (3)
O9—C47—C28	116.0 (3)	O10—C50—C26	116.9 (3)
O7—C47—O9	121.3 (3)	O1—C50—O10	121.6 (3)
O7—C47—C28	122.8 (3)	O1—C50—C26	121.5 (3)
F8—C49—C28	121.3 (3)	N4—C53—C26	124.7 (3)
F8—C49—C40	116.1 (3)	N4—C53—C54	117.5 (3)
C40—C49—C28	122.6 (3)	C54—C53—C26	117.8 (3)
C35—N2—H2A	123 (2)	F9—C54—C53	117.9 (3)
C35—N2—H2B	120 (2)	C55—C54—F9	118.9 (3)
H2A—N2—H2B	117 (3)	C55—C54—C53	123.2 (3)
F6—C56—C40	119.2 (3)	F10—C55—C48	119.9 (3)
F6—C56—C44	120.7 (3)	F10—C55—C54	120.7 (3)
C44—C56—C40	120.2 (3)	C54—C55—C48	119.4 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···F1	0.86 (3)	2.31 (3)	2.655 (4)	104 (2)
N1—H1B···O4	0.84 (3)	2.04 (4)	2.637 (4)	128 (3)
N1—H1B···F5ⁱ	0.84 (3)	2.40 (3)	3.154 (4)	150 (3)
N2—H2A···F5	0.83 (3)	2.39 (3)	2.670 (5)	101 (2)
N2—H2A···O10ⁱⁱ	0.83 (3)	2.58 (3)	3.363 (5)	158 (3)
N2—H2B···O7	0.85 (3)	2.03 (4)	2.643 (5)	129 (3)
N3—H3A···F4ⁱⁱⁱ	0.85 (3)	2.39 (3)	2.816 (4)	112 (3)
N3—H3A···F16	0.85 (3)	2.32 (3)	2.652 (4)	104 (2)
N3—H3A···O11ⁱⁱⁱ	0.85 (3)	2.50 (3)	3.337 (4)	167 (3)
N3—H3B···O5	0.85 (3)	2.04 (4)	2.654 (4)	129 (3)
N4—H4A···F9	0.83 (3)	2.36 (3)	2.650 (5)	101 (3)
N4—H4B···O1	0.86 (3)	2.01 (3)	2.648 (4)	130 (3)
N4—H4B···F16^iv	0.86 (3)	2.48 (3)	3.191 (5)	140 (3)
O9—H9···O5^v	0.82	1.84	2.660 (3)	175
O10—H10···O4^vi	0.82	1.86	2.675 (4)	178
O11—H11···O1^vi	0.82	1.82	2.643 (3)	177

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

Experimental details

Crystal data
Chemical formula	C₇H₃F₄NO₂
M_r	209.10
Crystal system, space group	Triclinic, P1
Temperature (K)	295
a, b, c (Å)	11.0367 (11), 11.3664 (11), 12.5702 (12)
α, β, γ (°)	80.378 (8), 79.764 (8), 82.011 (8)
V (Å³)	1520.2 (3)
Z	8
Radiation type	Cu Kα
µ (mm⁻¹)	1.79
Crystal size (mm)	0.50 × 0.30 × 0.15

Data collection
Diffractometer	Oxford Diffraction Xcalibur Sapphire3 Gemini ultra CCD diffractometer
Absorption correction	Multi-scan (CrysAlis PRO; Oxford Diffraction, 2010)
T_min, T_max	0.392, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	8708, 4791, 3521
R_int	0.031
(sin θ/λ)_max (Å⁻¹)	0.577

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.057, 0.177, 1.05
No. of reflections	4791
No. of parameters	533
No. of restraints	16
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.43, −0.24

Computer programs: CrysAlis PRO (Oxford Diffraction, 2010), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), OLEX2 (Dolomanov et al., 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1B···O4	0.84 (3)	2.04 (4)	2.637 (4)	128 (3)
N1—H1B···F5ⁱ	0.84 (3)	2.40 (3)	3.154 (4)	150 (3)
N2—H2A···O10ⁱⁱ	0.83 (3)	2.58 (3)	3.363 (5)	158 (3)
N2—H2B···O7	0.85 (3)	2.03 (4)	2.643 (5)	129 (3)
N3—H3A···O11ⁱⁱⁱ	0.85 (3)	2.50 (3)	3.337 (4)	167 (3)
N3—H3B···O5	0.85 (3)	2.04 (4)	2.654 (4)	129 (3)
N4—H4B···O1	0.86 (3)	2.01 (3)	2.648 (4)	130 (3)
N4—H4B···F16^iv	0.86 (3)	2.48 (3)	3.191 (5)	140 (3)
O9—H9···O5^v	0.82	1.84	2.660 (3)	175
O10—H10···O4^vi	0.82	1.86	2.675 (4)	178
O11—H11···O1^vi	0.82	1.82	2.643 (3)	177

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

Acknowledgements

This work was supported by grants from the National High Technology Development Project (863 Project; Nos. 2006 A A09Z408 GDSFC 06025194, 2005 A30503001, and 2006Z3E4041) and the National Natural Science Fund (No. 20772048)

References

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