3,3,3-Trifluoro-2-hydr-oxy-2-(trifluoro-meth-yl)propionic acid.

In the title perfluorinated hy-droxy-isobutyric acid derivative, C4H2F6O3, the mol-ecule shows approximately Cs symmetry. The carb-oxy group is nearly coplanar with the C-OH moiety and the O=C-C-O(H) torsion angle is 5.5 (2)°. An intra-molecular O-H⋯O hydrogen bond occurs. In the crystal, O-H⋯O hydrogen bonds connect the mol-ecules into supra-molecular chains along the a-axis direction.

Related literature

For the crystal structure of 2-hy­droxy-2-(trifluoro­meth­yl)proprionic acid, see: Soloshonok et al. (2007 ▶). For background to chelate ligands, see: Gade (1998 ▶). For graph-set analysis of hydrogen bonds, see: Etter et al. (1990 ▶); Bernstein et al. (1995 ▶).

Experimental

Crystal data

C4H2F6O3

M = 212.06

Orthorhombic,

a = 5.9949 (2) Å

b = 6.4007 (2) Å

c = 18.5642 (6) Å

V = 712.34 (4) Å3

Z = 4

Mo Kα radiation

μ = 0.26 mm−1

T = 200 K

0.53 × 0.53 × 0.34 mm

Data collection

Bruker APEXII CCD diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2008 ▶) T min = 0.908, T max = 1.000

3824 measured reflections

1052 independent reflections

1024 reflections with I > 2σ(I)

R int = 0.010

Refinement

R[F 2 > 2σ(F 2)] = 0.029

wR(F 2) = 0.076

S = 1.05

1052 reflections

120 parameters

H-atom parameters constrained

Δρmax = 0.31 e Å−3

Δρmin = −0.18 e Å−3

Data collection: APEX2 (Bruker, 2010 ▶); cell refinement: SAINT (Bruker, 2010 ▶); data reduction: SAINT; 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, 2012 ▶) and Mercury (Macrae et al., 2008 ▶); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009 ▶).

Click here for additional data file.

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536813003103/tk5193sup1.cif

Click here for additional data file.

Supplementary material file. DOI: 10.1107/S1600536813003103/tk5193Isup2.cdx

Click here for additional data file.

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536813003103/tk5193Isup3.hkl

Click here for additional data file.

Supplementary material file. DOI: 10.1107/S1600536813003103/tk5193Isup4.cml

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

C4H2F6O3	F(000) = 416
Mr = 212.06	Dx = 1.977 Mg m−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 2971 reflections
a = 5.9949 (2) Å	θ = 4.4–28.3°
b = 6.4007 (2) Å	µ = 0.26 mm−1
c = 18.5642 (6) Å	T = 200 K
V = 712.34 (4) Å3	Block, colourless
Z = 4	0.53 × 0.53 × 0.34 mm

Bruker APEXII CCD diffractometer	1052 independent reflections
Radiation source: fine-focus sealed tube	1024 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.010
φ and ω scans	θmax = 28.3°, θmin = 3.4°
Absorption correction: multi-scan (SADABS; Bruker, 2008)	h = −5→8
Tmin = 0.908, Tmax = 1.000	k = −6→8
3824 measured reflections	l = −22→24

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)] = 0.029	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.076	H-atom parameters constrained
S = 1.05	w = 1/[σ2(Fo2) + (0.0385P)2 + 0.2376P] where P = (Fo2 + 2Fc2)/3
1052 reflections	(Δ/σ)max < 0.001
120 parameters	Δρmax = 0.31 e Å−3
0 restraints	Δρmin = −0.18 e Å−3

Refinement. Due to the absence of a strong anomalous scatterer, the Flack parameter is meaningless. Thus, Friedel opposites (636 pairs) have been merged and the item was removed from the CIF.

	x	y	z	Uiso*/Ueq
F11	0.7286 (3)	0.2280 (3)	0.20540 (9)	0.0635 (5)
F12	0.6570 (2)	−0.0851 (3)	0.23660 (7)	0.0670 (5)
F13	0.99402 (19)	0.0068 (3)	0.21779 (6)	0.0464 (3)
F21	0.7614 (3)	−0.2907 (3)	0.02996 (9)	0.0702 (5)
F22	0.6292 (3)	−0.3692 (2)	0.13324 (12)	0.0747 (6)
F23	0.9814 (2)	−0.3310 (2)	0.11960 (9)	0.0527 (4)
O1	0.37188 (19)	−0.0103 (3)	0.11897 (8)	0.0403 (4)
H1	0.2541	0.0380	0.1010	0.060*
O2	0.5456 (2)	0.1808 (2)	0.03438 (8)	0.0372 (3)
O3	0.94390 (19)	0.0739 (2)	0.08055 (7)	0.0338 (3)
H3	0.8967	0.1464	0.0461	0.051*
C1	0.5428 (3)	0.0629 (3)	0.08432 (9)	0.0260 (3)
C2	0.7654 (3)	−0.0219 (3)	0.11475 (8)	0.0223 (3)
C3	0.7855 (3)	0.0308 (4)	0.19560 (10)	0.0340 (4)
C4	0.7833 (4)	−0.2590 (3)	0.10055 (12)	0.0382 (4)

	U11	U22	U33	U12	U13	U23
F11	0.0602 (10)	0.0626 (9)	0.0677 (9)	0.0226 (9)	−0.0209 (8)	−0.0336 (7)
F12	0.0487 (8)	0.1198 (14)	0.0326 (6)	−0.0194 (10)	0.0099 (6)	0.0174 (8)
F13	0.0276 (5)	0.0770 (9)	0.0347 (5)	0.0062 (7)	−0.0112 (4)	0.0026 (7)
F21	0.0736 (10)	0.0738 (10)	0.0632 (8)	0.0260 (10)	−0.0204 (8)	−0.0368 (8)
F22	0.0546 (9)	0.0326 (6)	0.1368 (17)	−0.0094 (7)	0.0194 (11)	0.0087 (9)
F23	0.0412 (7)	0.0433 (7)	0.0735 (9)	0.0204 (6)	−0.0056 (7)	0.0015 (7)
O1	0.0129 (5)	0.0608 (9)	0.0473 (7)	0.0005 (6)	0.0007 (5)	0.0171 (8)
O2	0.0213 (5)	0.0479 (8)	0.0424 (7)	0.0020 (6)	−0.0061 (5)	0.0185 (6)
O3	0.0133 (5)	0.0512 (8)	0.0368 (6)	−0.0008 (6)	0.0012 (5)	0.0206 (6)
C1	0.0142 (7)	0.0332 (8)	0.0305 (7)	0.0003 (7)	−0.0022 (6)	0.0021 (7)
C2	0.0127 (6)	0.0287 (7)	0.0254 (6)	0.0005 (6)	0.0014 (5)	0.0054 (6)
C3	0.0223 (8)	0.0501 (11)	0.0295 (8)	0.0020 (9)	−0.0016 (6)	−0.0007 (8)
C4	0.0301 (9)	0.0329 (9)	0.0517 (11)	0.0049 (8)	−0.0019 (9)	−0.0029 (9)

F11—C3	1.320 (3)	O1—H1	0.8400
F12—C3	1.313 (3)	O2—C1	1.196 (2)
F13—C3	1.325 (2)	O3—C2	1.3870 (19)
F21—C4	1.332 (3)	O3—H3	0.8400
F22—C4	1.312 (3)	C1—C2	1.547 (2)
F23—C4	1.322 (2)	C2—C3	1.543 (2)
O1—C1	1.297 (2)	C2—C4	1.544 (3)
C1—O1—H1	109.5	F12—C3—F13	107.93 (17)
C2—O3—H3	109.5	F11—C3—F13	108.19 (19)
O2—C1—O1	128.59 (16)	F12—C3—C2	113.24 (17)
O2—C1—C2	119.48 (15)	F11—C3—C2	108.83 (17)
O1—C1—C2	111.93 (13)	F13—C3—C2	110.55 (15)
O3—C2—C3	106.75 (14)	F22—C4—F23	108.76 (18)
O3—C2—C4	107.61 (15)	F22—C4—F21	107.7 (2)
C3—C2—C4	112.06 (15)	F23—C4—F21	107.36 (18)
O3—C2—C1	110.08 (12)	F22—C4—C2	113.62 (17)
C3—C2—C1	110.23 (14)	F23—C4—C2	111.08 (17)
C4—C2—C1	110.02 (15)	F21—C4—C2	108.10 (17)
F12—C3—F11	107.96 (19)
O2—C1—C2—O3	5.5 (2)	O3—C2—C3—F13	−44.9 (2)
O1—C1—C2—O3	−174.76 (17)	C4—C2—C3—F13	72.7 (2)
O2—C1—C2—C3	123.00 (19)	C1—C2—C3—F13	−164.42 (16)
O1—C1—C2—C3	−57.3 (2)	O3—C2—C4—F22	176.80 (17)
O2—C1—C2—C4	−112.92 (19)	C3—C2—C4—F22	59.8 (2)
O1—C1—C2—C4	66.81 (19)	C1—C2—C4—F22	−63.3 (2)
O3—C2—C3—F12	−166.13 (17)	O3—C2—C4—F23	53.8 (2)
C4—C2—C3—F12	−48.6 (2)	C3—C2—C4—F23	−63.2 (2)
C1—C2—C3—F12	74.3 (2)	C1—C2—C4—F23	173.74 (15)
O3—C2—C3—F11	73.80 (18)	O3—C2—C4—F21	−63.7 (2)
C4—C2—C3—F11	−168.63 (17)	C3—C2—C4—F21	179.21 (16)
C1—C2—C3—F11	−45.7 (2)	C1—C2—C4—F21	56.2 (2)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···O2	0.84	2.13	2.6274 (17)	118
O1—H1···O3i	0.84	1.91	2.7170 (17)	160
O3—H3···O2ii	0.84	2.06	2.7186 (17)	135

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H3⋯O2	0.84	2.13	2.6274 (17)	118
O1—H1⋯O3i	0.84	1.91	2.7170 (17)	160
O3—H3⋯O2ii	0.84	2.06	2.7186 (17)	135

Symmetry codes: (i) ; (ii) .