2,4,6-Trifluoro­aniline

Betz, R.; Klüfers, P.

doi:10.1107/S1600536808035083

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 64| Part 11| November 2008| Page o2242

doi:10.1107/S1600536808035083

Open

access

2,4,6-Trifluoroaniline

Richard Betz ^a and Peter Klüfers ^a ^*

^aLudwig-Maximilians Universität, Department Chemie und Biochemie, Butenandtstrasse 5–13 (Haus D), 81377 München, Germany
^*Correspondence e-mail: kluef@cup.uni-muenchen.de

(Received 10 September 2008; accepted 28 October 2008; online 31 October 2008)

The title compound, C₆H₄F₃N, is a fluoro derivative of aniline. The molecule shows non-crystallographic mirror symmetry. Bond lengths are normal. The C—C—C angles show some deviation from the expected ideal values by up to 5°, a finding which is in accordance with a similar structure in the literature. In the crystal structure H⋯F contacts and H⋯N contacts lead to the formation of sheets whose surfaces are made up by the hydrophobic phenyl rings.

Related literature

For the crystal structure of a related compound, see: Gdaniec (2007 ). For graph-set analysis, see: Bernstein et al. (1995 ); Etter et al. (1990 ).

Experimental

Crystal data

C₆H₄F₃N
M_r = 147.10
Orthorhombic, P 2₁ 2₁ 2₁
a = 6.3220 (6) Å
b = 24.792 (2) Å
c = 3.8545 (5) Å
V = 604.14 (11) Å³
Z = 4
Mo Kα radiation
μ = 0.16 mm⁻¹
T = 200 (2) K
0.50 × 0.09 × 0.05 mm

Data collection

Oxford Diffraction KappaCCD diffractometer
Absorption correction: multi-scan (SCALE3 ABSPACK in CrysAlis RED; Oxford Diffraction, 2005 $[Oxford Diffraction (2005). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon,England.]$ )) T_min = 0.921, T_max = 0.992
4517 measured reflections
775 independent reflections
489 reflections with I > 2σ(I)
R_int = 0.034

Refinement

R[F² > 2σ(F²)] = 0.034
wR(F²) = 0.082
S = 0.94
775 reflections
91 parameters
H-atom parameters constrained
Δρ_max = 0.13 e Å⁻³
Δρ_min = −0.16 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H71⋯N1ⁱ	0.90	2.26	3.110 (3)	157
N1—H72⋯F3ⁱⁱ	0.88	2.31	3.086 (2)	147
Symmetry codes: (i) $[-x+{\script{3\over 2}}, -y, z-{\script{1\over 2}}]$ ; (ii) $[-x+{\script{1\over 2}}, -y, z-{\script{1\over 2}}]$ .

Data collection: CrysAlis CCD (Oxford Diffraction, 2005 $[Oxford Diffraction (2005). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon,England.]$ ); cell refinement: CrysAlis RED (Oxford Diffraction, 2005 $[Oxford Diffraction (2005). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon,England.]$ ); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996 ) and Mercury (Macrae et al., 2006 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808035083/rn2051sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808035083/rn2051Isup2.hkl

checkCIF report

Comment top

In a program focused on the synthesis of derivatives of phenylarsonic acid a number of substituted aniline-derivatives were chosen as starting materials. In order to compare the influence of an arsonic group on the geometry of these starting materials, the crystal structure of 2,4,6-trifluoroaniline was elucidated by means of single-crystal X-ray diffraction.

In the molecule (Fig. 1) the C–C–C angles deviate from the expected ideal value of 120° by up to 5°. Angles bigger than the expected value are invariably found at C atoms bonded to fluorine, the smallest angle being present on the C atom bearing the amino group. This finding is in agreement with the situation observed in 2,3,4,5,6-pentafluoroaniline (Gdaniec, 2007).

In the crystal structure hydrogen bonds between fluorine and the amino group are present. If contacts whose ranges fall 0.2Å below the sum of van der Waals radii of the respective atoms are taken into consideration, only one of the F atoms in ortho position to the amino group is participating in these intermolecular interactions. These connect the molecules into sheets parallel to [1 0 1]. The surfaces of these sheets are made up by the aromatic moieties (Fig. 2 and Fig. 3). In terms of graph-set analysis (Etter et al., 1990; Bernstein et al., 1995) the N–H···F pattern should be assigned a C(5) descriptor on the unitary level while the remaining H atom on nitrogen participates in a cooperative chain of hydrogen bonds (N–H···N).

Related literature top

For the crystal structure of a related compound, see: Gdaniec (2007). For graph-set analysis, see: Bernstein et al. (1995); Etter et al. (1990).

Experimental top

The compound was obtained commercially from Fluorochem. Crystals suitable for X-ray diffraction studies were obtained upon cooling the compound to 4 °C in a fridge.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2005); cell refinement: CrysAlis RED (Oxford Diffraction, 2005); data reduction: CrysAlis RED (Oxford Diffraction, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of the title compound, with atom labels and anisotropic displacement ellipsoids (drawn at 50% probability level) for non-H atoms.
	Fig. 2. The packing of the title compound, viewed along [0 0 - 1].
	Fig. 3. Intermolecular interactions in the crystal structure of the title compound, viewed along [0 0 1]. Symmetry operators: i -x + 3/2, -y, z - 1/2; ii -x + 1/2, -y, z - 1/2.

2,4,6-Trifluoroaniline top

Crystal data top

C₆H₄F₃N	F(000) = 296
M_r = 147.10	D_x = 1.617 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 1719 reflections
a = 6.3220 (6) Å	θ = 4.1–26.3°
b = 24.792 (2) Å	µ = 0.16 mm⁻¹
c = 3.8545 (5) Å	T = 200 K
V = 604.14 (11) Å³	Rod, colourless
Z = 4	0.50 × 0.09 × 0.05 mm

Data collection top

Oxford Diffraction KappaCCD diffractometer	775 independent reflections
Radiation source: fine-focus sealed tube	489 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.034
ω scans	θ_max = 26.4°, θ_min = 4.1°
Absorption correction: multi-scan (SCALE3 ABSPACK in CrysAlis RED; Oxford Diffraction, 2005))	h = −7→7
T_min = 0.921, T_max = 0.992	k = −30→30
4517 measured reflections	l = −4→3

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)] = 0.034	Hydrogen site location: difference Fourier map
wR(F²) = 0.082	H-atom parameters constrained
S = 0.94	w = 1/[σ²(F_o²) + (0.0505P)²] where P = (F_o² + 2F_c²)/3
775 reflections	(Δ/σ)_max < 0.001
91 parameters	Δρ_max = 0.13 e Å⁻³
0 restraints	Δρ_min = −0.16 e Å⁻³

Crystal data top

C₆H₄F₃N	V = 604.14 (11) Å³
M_r = 147.10	Z = 4
Orthorhombic, P2₁2₁2₁	Mo Kα radiation
a = 6.3220 (6) Å	µ = 0.16 mm⁻¹
b = 24.792 (2) Å	T = 200 K
c = 3.8545 (5) Å	0.50 × 0.09 × 0.05 mm

Data collection top

Oxford Diffraction KappaCCD diffractometer	775 independent reflections
Absorption correction: multi-scan (SCALE3 ABSPACK in CrysAlis RED; Oxford Diffraction, 2005))	489 reflections with I > 2σ(I)
T_min = 0.921, T_max = 0.992	R_int = 0.034
4517 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.034	0 restraints
wR(F²) = 0.082	H-atom parameters constrained
S = 0.94	Δρ_max = 0.13 e Å⁻³
775 reflections	Δρ_min = −0.16 e Å⁻³
91 parameters

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
F1	0.8818 (2)	0.10411 (5)	−0.1028 (5)	0.0618 (5)
F2	0.4694 (2)	0.24248 (5)	0.3783 (5)	0.0712 (6)
F3	0.2254 (2)	0.06360 (6)	0.3828 (5)	0.0715 (6)
N1	0.5886 (3)	0.02701 (7)	0.0726 (7)	0.0564 (7)
H71	0.6769	0.0202	−0.1054	0.068*
H72	0.4647	0.0109	0.0632	0.068*
C1	0.5551 (4)	0.08172 (8)	0.1384 (7)	0.0398 (6)
C2	0.7034 (4)	0.12061 (9)	0.0624 (7)	0.0414 (6)
C3	0.6805 (4)	0.17436 (8)	0.1376 (7)	0.0447 (7)
H3	0.7868	0.2000	0.0811	0.054*
C4	0.4963 (4)	0.18920 (8)	0.2983 (7)	0.0451 (7)
C5	0.3394 (4)	0.15382 (8)	0.3828 (8)	0.0480 (7)
H5	0.2124	0.1652	0.4922	0.058*
C6	0.3757 (4)	0.10062 (9)	0.3004 (7)	0.0444 (7)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
F1	0.0434 (9)	0.0688 (9)	0.0731 (11)	0.0014 (7)	0.0104 (9)	−0.0040 (10)
F2	0.0870 (11)	0.0420 (8)	0.0845 (14)	0.0118 (8)	−0.0120 (14)	−0.0085 (10)
F3	0.0534 (9)	0.0641 (9)	0.0969 (14)	−0.0156 (7)	0.0105 (12)	0.0123 (10)
N1	0.0574 (14)	0.0408 (11)	0.0712 (18)	−0.0029 (10)	−0.0014 (15)	−0.0017 (12)
C1	0.0441 (13)	0.0354 (12)	0.0397 (16)	−0.0004 (10)	−0.0070 (14)	0.0045 (12)
C2	0.0379 (13)	0.0476 (14)	0.0386 (16)	0.0022 (11)	−0.0023 (13)	0.0011 (13)
C3	0.0503 (17)	0.0412 (14)	0.0426 (17)	−0.0103 (11)	−0.0064 (16)	0.0057 (14)
C4	0.0573 (16)	0.0326 (12)	0.0453 (17)	0.0063 (12)	−0.0101 (16)	−0.0018 (12)
C5	0.0445 (16)	0.0496 (14)	0.0499 (17)	0.0094 (12)	0.0004 (16)	0.0009 (16)
C6	0.0408 (13)	0.0473 (14)	0.0453 (19)	−0.0087 (12)	0.0001 (14)	0.0094 (13)

Geometric parameters (Å, º) top

F1—C2	1.358 (3)	C1—C6	1.377 (3)
F2—C4	1.367 (2)	C2—C3	1.371 (3)
F3—C6	1.359 (2)	C3—C4	1.369 (4)
N1—C1	1.396 (3)	C3—H3	0.9500
N1—H71	0.9009	C4—C5	1.364 (3)
N1—H72	0.8798	C5—C6	1.376 (3)
C1—C2	1.377 (3)	C5—H5	0.9500

C1—N1—H71	114.6	C2—C3—H3	121.7
C1—N1—H72	108.3	C5—C4—F2	118.5 (2)
H71—N1—H72	115.8	C5—C4—C3	123.6 (2)
C2—C1—C6	114.8 (2)	F2—C4—C3	117.9 (2)
C2—C1—N1	122.6 (2)	C4—C5—C6	116.1 (2)
C6—C1—N1	122.5 (2)	C4—C5—H5	121.9
F1—C2—C3	118.7 (2)	C6—C5—H5	121.9
F1—C2—C1	117.04 (19)	F3—C6—C5	118.5 (2)
C3—C2—C1	124.3 (2)	F3—C6—C1	116.9 (2)
C4—C3—C2	116.5 (2)	C5—C6—C1	124.6 (2)
C4—C3—H3	121.7

C6—C1—C2—F1	−178.9 (2)	F2—C4—C5—C6	−179.2 (2)
N1—C1—C2—F1	4.2 (4)	C3—C4—C5—C6	0.7 (4)
C6—C1—C2—C3	0.0 (4)	C4—C5—C6—F3	179.2 (3)
N1—C1—C2—C3	−176.9 (3)	C4—C5—C6—C1	−0.8 (4)
F1—C2—C3—C4	178.8 (2)	C2—C1—C6—F3	−179.5 (2)
C1—C2—C3—C4	−0.1 (4)	N1—C1—C6—F3	−2.7 (4)
C2—C3—C4—C5	−0.2 (4)	C2—C1—C6—C5	0.5 (4)
C2—C3—C4—F2	179.6 (2)	N1—C1—C6—C5	177.3 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H71···N1ⁱ	0.90	2.26	3.110 (3)	157
N1—H72···F3ⁱⁱ	0.88	2.31	3.086 (2)	147

Symmetry codes: (i) −x+3/2, −y, z−1/2; (ii) −x+1/2, −y, z−1/2.

Experimental details

Crystal data
Chemical formula	C₆H₄F₃N
M_r	147.10
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	200
a, b, c (Å)	6.3220 (6), 24.792 (2), 3.8545 (5)
V (Å³)	604.14 (11)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.16
Crystal size (mm)	0.50 × 0.09 × 0.05

Data collection
Diffractometer	Oxford Diffraction KappaCCD diffractometer
Absorption correction	Multi-scan (SCALE3 ABSPACK in CrysAlis RED; Oxford Diffraction, 2005))
T_min, T_max	0.921, 0.992
No. of measured, independent and observed [I > 2σ(I)] reflections	4517, 775, 489
R_int	0.034
(sin θ/λ)_max (Å⁻¹)	0.625

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.034, 0.082, 0.94
No. of reflections	775
No. of parameters	91
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.13, −0.16

Computer programs: CrysAlis CCD (Oxford Diffraction, 2005), CrysAlis RED (Oxford Diffraction, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEPIII (Burnett & Johnson, 1996) and Mercury (Macrae et al., 2006).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H71···N1ⁱ	0.90	2.26	3.110 (3)	157.3
N1—H72···F3ⁱⁱ	0.88	2.31	3.086 (2)	146.9

Symmetry codes: (i) −x+3/2, −y, z−1/2; (ii) −x+1/2, −y, z−1/2.

Acknowledgements

The authors thank Dr Peter Mayer for professional support.

References

Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555–1573. CrossRef CAS Web of Science Google Scholar
Burnett, M. N. & Johnson, C. K. (1996). ORTEPIII. Report ORNL-6895. Oak Ridge National Laboratory, Tennessee, USA. Google Scholar
Etter, M. C., MacDonald, J. C. & Bernstein, J. (1990). Acta Cryst. B46, 256–262. CrossRef CAS Web of Science IUCr Journals Google Scholar
Gdaniec, M. (2007). Acta Cryst. E63, o2954. Web of Science CSD CrossRef IUCr Journals Google Scholar
Macrae, C. F., Edgington, P. R., McCabe, P., Pidcock, E., Shields, G. P., Taylor, R., Towler, M. & van de Streek, J. (2006). J. Appl. Cryst. 39, 453–457. Web of Science CrossRef CAS IUCr Journals Google Scholar
Oxford Diffraction (2005). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon,England. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar