2,4,6-Trichloro­aniline

The cell parameters of the title compound, C₆H₄Cl₃N, have already been determined [Schlemper & Konnert (1967). Acta Cryst. 22, 918; Andrianov et al. (1971). Zh. Strukt. Khim. 12, 736–737], but no coordinates were available. There are two mol­ecules in the asymmetric unit. The mol­ecules are linked through N—H...N and N—H...Cl hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.022
• wR factor = 0.052
• Data-to-parameter ratio = 12.9

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT152_ALERT_1_C Supplied and Calc Volume s.u. Inconsistent .....          ?
PLAT480_ALERT_4_C Long H...A H-Bond Reported H2B    ..  CL6     ..       2.85 Ang.
PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd.  #          1
              C6 H4 Cl3 N
PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd.  #          2
              C6 H4 Cl3 N

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           26.37
           From the CIF: _reflns_number_total               2640
           Count of symmetry unique reflns         1737
           Completeness (_total/calc)            151.99%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured       903
           Fraction of Friedel pairs measured     0.520
           Are heavy atom types Z>Si present        yes
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          1

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

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 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
   4 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

---

S1. Comment

In the present work, the structure of trichloroaniline has been determined at 100 K, as part of our study of the effect of ring and side chain substitutions on the solid state structures of chemically and biologically important compounds (Gowda et al., 2000; Gowda et al., 2004; Gowda et al., 2006; Gowda, Foro, Fuess, 2007; Gowda, Paulus, Svoboda & Fuess, 2007). The cell pararameters of the title compound have already been determined (Schlemper & Konnert, 1967; Andrianov et al., 1971). There are two molecules in the asymmetric unit. The molecules are linked through N—H···N and N—H···Cl hydrogen bonds (Table 1 & Fig. 2).

Related literature

For related literature, see: Andrianov et al. (1971); Gowda et al. (2000, 2004, 2006); Gowda, Foro & Fuess (2007); Gowda, Paulus, Svoboda & Fuess (2007); Schlemper & Konnert (1967).

S2. Experimental

Single crystals of the title compound were obtained from a slow evaporation of an ethanolic solution of the analytical grade commercial sample.

S3. Refinement

The H atoms were located in difference map and their positions refined, with U_iso(H) = 1.2 U_eq (parent atom).

Computing details

Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell refinement: CrysAlis RED (Oxford Diffraction, 2006); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003) and ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97.

Figures

	Fig. 1. Molecular structure of the title compound showing the atom labelling scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are represented as small spheres of arbitrary radii.
	Fig. 2. The crystal packing of the title compound showing the hydrogen bonds as dashed lines.

2,4,6-Trichloroaniline

Crystal data

C6H4Cl3N	F(000) = 392
Mr = 196.45	Dx = 1.778 Mg m^−3
Monoclinic, P21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2yb	Cell parameters from 2998 reflections
a = 13.1933 (9) Å	θ = 2.8–26.5°
b = 3.7913 (3) Å	µ = 1.16 mm^−1
c = 15.774 (1) Å	T = 100 K
β = 111.546 (8)°	Needle, colourless
V = 733.88 (9) Å^3	0.40 × 0.06 × 0.04 mm
Z = 4

Data collection

Oxford Diffraction Xcalibur single-crystal X-ray diffractometer with a Sapphire CCD detector	2640 independent reflections
Radiation source: Enhance (Mo) X-ray Source	2394 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.020
Detector resolution: 8.4012 pixels mm^-1	θmax = 26.4°, θmin = 2.5°
Rotation method data acquisition using ω and φ scans	h = −16→16
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006)	k = −3→4
Tmin = 0.654, Tmax = 0.955	l = −19→19
6014 measured reflections

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.022	Only H-atom coordinates refined
wR(F^2) = 0.052	w = 1/[σ^2(Fo^2) + (0.0308P)^2 + 0.0195P] where P = (Fo^2 + 2Fc^2)/3
S = 1.06	(Δ/σ)max = 0.001
2640 reflections	Δρmax = 0.31 e Å^−3
205 parameters	Δρmin = −0.20 e Å^−3
1 restraint	Absolute structure: Flack (1983), 909 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.05 (6)

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
C1	−0.17763 (17)	0.1364 (8)	−0.48017 (15)	0.0136 (5)
C2	−0.15064 (17)	0.1814 (7)	−0.38618 (15)	0.0136 (5)
C3	−0.21934 (19)	0.0893 (7)	−0.34146 (16)	0.0161 (5)
H3	−0.1964 (19)	0.127 (8)	−0.2782 (16)	0.019*
C4	−0.32004 (18)	−0.0566 (7)	−0.39203 (16)	0.0145 (5)
C5	−0.35067 (17)	−0.1116 (8)	−0.48459 (15)	0.0139 (5)
H5	−0.4162 (19)	−0.201 (7)	−0.5161 (16)	0.017*
C6	−0.27979 (18)	−0.0155 (7)	−0.52667 (14)	0.0145 (5)
C7	0.18568 (16)	−0.1233 (8)	−0.04221 (14)	0.0123 (5)
C8	0.26254 (17)	−0.2849 (7)	−0.07128 (14)	0.0137 (5)
C9	0.36317 (17)	−0.4004 (8)	−0.01229 (14)	0.0130 (5)
H9	0.4118 (18)	−0.505 (7)	−0.0361 (15)	0.016*
C10	0.38899 (16)	−0.3535 (7)	0.08034 (14)	0.0129 (5)
C11	0.31648 (17)	−0.1988 (7)	0.11387 (15)	0.0124 (5)
H11	0.3328 (18)	−0.175 (7)	0.1782 (16)	0.015*
C12	0.21624 (17)	−0.0889 (7)	0.05230 (15)	0.0127 (5)
N1	−0.10582 (16)	0.2177 (6)	−0.52298 (15)	0.0183 (5)
H1A	−0.058 (2)	0.357 (9)	−0.4968 (17)	0.022*
H1B	−0.138 (2)	0.262 (7)	−0.5786 (17)	0.022*
N2	0.08434 (16)	−0.0177 (6)	−0.10248 (14)	0.0167 (5)
H2A	0.077 (2)	0.014 (8)	−0.1578 (18)	0.020*
H2B	0.0519 (19)	0.132 (8)	−0.0836 (16)	0.020*
Cl1	−0.02316 (4)	0.36022 (18)	−0.32306 (4)	0.01969 (14)
Cl2	−0.40873 (4)	−0.17199 (18)	−0.33787 (4)	0.01946 (15)
Cl3	−0.31863 (5)	−0.09196 (19)	−0.64317 (4)	0.02145 (16)
Cl4	0.22936 (4)	−0.34462 (19)	−0.18807 (3)	0.01808 (15)
Cl5	0.51505 (4)	−0.49705 (17)	0.15626 (4)	0.01731 (15)
Cl6	0.12272 (4)	0.09515 (17)	0.09410 (4)	0.01712 (15)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0135 (10)	0.0103 (14)	0.0163 (11)	0.0037 (11)	0.0047 (9)	0.0008 (10)
C2	0.0108 (10)	0.0084 (14)	0.0167 (11)	−0.0006 (11)	−0.0007 (9)	0.0011 (10)
C3	0.0191 (11)	0.0136 (15)	0.0128 (11)	0.0024 (11)	0.0027 (9)	0.0003 (11)
C4	0.0155 (11)	0.0084 (15)	0.0228 (12)	0.0008 (11)	0.0105 (10)	0.0019 (10)
C5	0.0109 (10)	0.0118 (15)	0.0165 (11)	−0.0002 (12)	0.0020 (9)	0.0004 (11)
C6	0.0173 (11)	0.0131 (15)	0.0100 (10)	0.0032 (11)	0.0014 (9)	−0.0015 (10)
C7	0.0127 (10)	0.0080 (13)	0.0165 (11)	−0.0026 (11)	0.0059 (9)	0.0025 (10)
C8	0.0162 (11)	0.0142 (15)	0.0117 (10)	−0.0056 (11)	0.0061 (9)	−0.0018 (10)
C9	0.0132 (10)	0.0106 (14)	0.0178 (11)	−0.0026 (11)	0.0087 (9)	−0.0017 (10)
C10	0.0091 (10)	0.0115 (14)	0.0162 (11)	0.0002 (11)	0.0024 (9)	0.0027 (11)
C11	0.0144 (11)	0.0091 (15)	0.0132 (11)	−0.0030 (10)	0.0047 (9)	−0.0001 (10)
C12	0.0135 (10)	0.0093 (15)	0.0194 (11)	−0.0017 (11)	0.0109 (9)	−0.0009 (10)
N1	0.0165 (10)	0.0214 (15)	0.0166 (10)	−0.0027 (10)	0.0056 (9)	−0.0021 (10)
N2	0.0134 (10)	0.0205 (14)	0.0165 (10)	0.0031 (10)	0.0060 (8)	0.0023 (10)
Cl1	0.0148 (3)	0.0204 (4)	0.0189 (3)	−0.0034 (3)	0.0004 (2)	0.0003 (3)
Cl2	0.0201 (3)	0.0214 (4)	0.0196 (3)	−0.0022 (3)	0.0105 (2)	0.0010 (3)
Cl3	0.0260 (3)	0.0255 (4)	0.0116 (3)	−0.0037 (3)	0.0056 (2)	−0.0032 (3)
Cl4	0.0162 (3)	0.0254 (4)	0.0120 (3)	−0.0030 (3)	0.0044 (2)	−0.0027 (3)
Cl5	0.0130 (3)	0.0201 (4)	0.0163 (3)	0.0027 (3)	0.0025 (2)	0.0003 (2)
Cl6	0.0166 (3)	0.0168 (4)	0.0220 (3)	0.0013 (3)	0.0119 (2)	−0.0020 (3)

Geometric parameters (Å, º)

C1—N1	1.385 (3)	C7—C12	1.400 (3)
C1—C6	1.400 (3)	C8—C9	1.383 (3)
C1—C2	1.402 (3)	C8—Cl4	1.745 (2)
C2—C3	1.382 (3)	C9—C10	1.385 (3)
C2—Cl1	1.746 (2)	C9—H9	0.94 (2)
C3—C4	1.389 (3)	C10—C11	1.382 (3)
C3—H3	0.94 (2)	C10—Cl5	1.742 (2)
C4—C5	1.380 (3)	C11—C12	1.386 (3)
C4—Cl2	1.739 (2)	C11—H11	0.96 (2)
C5—C6	1.380 (3)	C12—Cl6	1.744 (2)
C5—H5	0.89 (2)	N1—H1A	0.81 (3)
C6—Cl3	1.741 (2)	N1—H1B	0.84 (2)
C7—N2	1.385 (3)	N2—H2A	0.85 (3)
C7—C8	1.398 (3)	N2—H2B	0.83 (3)
N1—C1—C6	122.4 (2)	C9—C8—C7	123.41 (19)
N1—C1—C2	122.3 (2)	C9—C8—Cl4	118.41 (17)
C6—C1—C2	115.2 (2)	C7—C8—Cl4	118.17 (16)
C3—C2—C1	123.3 (2)	C8—C9—C10	118.2 (2)
C3—C2—Cl1	118.81 (17)	C8—C9—H9	119.4 (14)
C1—C2—Cl1	117.87 (18)	C10—C9—H9	122.4 (14)
C2—C3—C4	118.4 (2)	C11—C10—C9	121.4 (2)
C2—C3—H3	119.1 (15)	C11—C10—Cl5	119.34 (16)
C4—C3—H3	122.4 (15)	C9—C10—Cl5	119.23 (17)
C5—C4—C3	121.0 (2)	C10—C11—C12	118.41 (19)
C5—C4—Cl2	119.55 (18)	C10—C11—H11	121.7 (14)
C3—C4—Cl2	119.49 (17)	C12—C11—H11	119.8 (14)
C6—C5—C4	118.8 (2)	C11—C12—C7	123.1 (2)
C6—C5—H5	121.5 (15)	C11—C12—Cl6	118.73 (17)
C4—C5—H5	119.6 (15)	C7—C12—Cl6	118.21 (16)
C5—C6—C1	123.3 (2)	C1—N1—H1A	116.0 (18)
C5—C6—Cl3	118.36 (17)	C1—N1—H1B	112.1 (17)
C1—C6—Cl3	118.35 (17)	H1A—N1—H1B	114 (3)
N2—C7—C8	122.3 (2)	C7—N2—H2A	117.7 (17)
N2—C7—C12	122.1 (2)	C7—N2—H2B	116.6 (17)
C8—C7—C12	115.46 (19)	H2A—N2—H2B	113 (3)
N1—C1—C2—C3	−177.4 (3)	N2—C7—C8—C9	−178.4 (3)
C6—C1—C2—C3	−0.9 (4)	C12—C7—C8—C9	−1.0 (4)
N1—C1—C2—Cl1	2.1 (4)	N2—C7—C8—Cl4	1.5 (4)
C6—C1—C2—Cl1	178.57 (19)	C12—C7—C8—Cl4	178.84 (19)
C1—C2—C3—C4	0.3 (4)	C7—C8—C9—C10	0.0 (4)
Cl1—C2—C3—C4	−179.3 (2)	Cl4—C8—C9—C10	−179.8 (2)
C2—C3—C4—C5	0.6 (4)	C8—C9—C10—C11	0.6 (4)
C2—C3—C4—Cl2	−179.5 (2)	C8—C9—C10—Cl5	179.9 (2)
C3—C4—C5—C6	−0.7 (4)	C9—C10—C11—C12	−0.2 (4)
Cl2—C4—C5—C6	179.4 (2)	Cl5—C10—C11—C12	−179.51 (19)
C4—C5—C6—C1	−0.1 (4)	C10—C11—C12—C7	−0.8 (4)
C4—C5—C6—Cl3	179.1 (2)	C10—C11—C12—Cl6	178.2 (2)
N1—C1—C6—C5	177.3 (3)	N2—C7—C12—C11	178.8 (2)
C2—C1—C6—C5	0.8 (4)	C8—C7—C12—C11	1.4 (4)
N1—C1—C6—Cl3	−1.9 (4)	N2—C7—C12—Cl6	−0.3 (4)
C2—C1—C6—Cl3	−178.4 (2)	C8—C7—C12—Cl6	−177.7 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···N1^i	0.81 (3)	2.48 (3)	3.229 (3)	155 (2)
N1—H1A···Cl1	0.81 (3)	2.61 (3)	2.983 (2)	110 (2)
N1—H1B···Cl3	0.84 (3)	2.60 (3)	2.991 (2)	110 (2)
N2—H2A···Cl1	0.85 (3)	2.78 (3)	3.542 (2)	150 (2)
N2—H2B···Cl6^ii	0.83 (3)	2.85 (3)	3.626 (2)	156 (2)

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