Picric acid–2,4,6-trichloro­aniline (1/1)

Wang, W.-Q.

doi:10.1107/S160053681100571X

organic compounds

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Volume 67| Part 4| April 2011| Page o860

doi:10.1107/S160053681100571X

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Picric acid–2,4,6-trichloroaniline (1/1)

Wan-Qiang Wang ^a ^*

^aDepartment of Chemistry and Biology, Xiangfan University, Xiangfan 441053, People's Republic of China
^*Correspondence e-mail: wqwang2008@163.com

(Received 11 February 2011; accepted 16 February 2011; online 12 March 2011)

In the title adduct, C₆H₄Cl₃N·C₆H₃N₃O₇, the two benzene rings are almost coplanar, with a dihedral angle of 1.19 (1)° and an inter-ring centroid–centroid separation of 4.816 (2) Å. The crystal structure is stabilized by intermolecular N—H⋯O_nitro hydrogen bonds, giving a chain structure. In addition, there are phenol–nitro O—H⋯O interactions.

Related literature

The crystal structures of picrate salts and picric acid complexes have been studied to investigate charge-transfer processes, see: Nagata et al. (1995 ); Smith et al. (2004 ). For the crystal structures of picric acid complexes, see: Li (2009 ); Sivaramkumar et al. (2010 ).

Experimental

Crystal data

C₆H₄Cl₃N·C₆H₃N₃O₇
M_r = 425.57
Orthorhombic, P b c a
a = 9.2162 (14) Å
b = 10.0174 (14) Å
c = 35.051 (5) Å
V = 3236.0 (8) Å³
Z = 8
Mo Kα radiation
μ = 0.61 mm⁻¹
T = 298 K
0.16 × 0.12 × 0.10 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1997 ) T_min = 0.908, T_max = 0.941
19589 measured reflections
3186 independent reflections
2287 reflections with I > 2σ(I)
R_int = 0.076

Refinement

R[F² > 2σ(F²)] = 0.058
wR(F²) = 0.120
S = 1.10
3186 reflections
244 parameters
2 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.21 e Å⁻³
Δρ_min = −0.27 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1A⋯O7	0.89 (4)	1.76 (4)	2.546 (4)	145 (4)
N4—H4A⋯O5ⁱ	0.85 (2)	2.39 (2)	3.159 (4)	150 (3)
N4—H4B⋯O6ⁱⁱ	0.84 (2)	2.40 (2)	3.194 (4)	156 (4)
Symmetry codes: (i) $[-x+{\script{3\over 2}}, y-{\script{1\over 2}}, z]$ ; (ii) $[-x+{\script{1\over 2}}, y-{\script{1\over 2}}, z]$ .

Data collection: SMART (Bruker, 2001 ); cell refinement: SAINT (Bruker, 1999 ); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S160053681100571X/zs2097sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053681100571X/zs2097Isup2.hkl

checkCIF report

Comment top

2,4,6-Trinitrophenol (picric acid), was primarily used to manufacture explosives and is also used as an intermediate in dye manufacturing. The crystal structures of a large number of picrate salts and picric acid complexes have been studied to determine the conformational features and to understand charge transfer processes (Li et al., 2009; Nagata et al., 1995; Sivaramkumar et al., 2010, Smith et al., 2004). We herein report the 1:1 cocrystal structure of 2,4,6-trichloroaniline and picric acid C₆H₄Cl₃N . C₆H₃N₃O₇ (I) (Fig. 1). In the title adduct, the two phenyl rings are almost coplanar with a dihedral angle of 1.19 (1)° and an inter-ring centroid separation of 4.816 (2) Å. The crystal structure is stabilized by intermolecular N—H···O_nitro hydrogen bonds giving a one-dimensional chain structure and in addition, intramolecular N—H···Cl and phenol O—H···O(nitro) interactions are observed (Table 1).

Related literature top

The crystal structures of picrate salts and picric acid complexes have been studied to investigate charge-transfer processes, see: Nagata et al. (1995); Smith et al. (2004). For the crystal structures of picric acid complexes, see: Li et al. (2009); Sivaramkumar et al. (2010).

Experimental top

2,4,6-Trichloroaniline (0.19 g, 1.0 mmol) and picric acid (0.23 g, 1.0 mmol) were dissolved in MeOH-CH₂Cl₂ (3:1) and the mixture was kept at room temperature for one week. Red crystals suitable for single-crystal X-ray diffraction were obtained.

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 1999); data reduction: SAINT (Bruker, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

Fig. 1. The title compound with the atom-numbering scheme, with displacement ellipsoids drawn at the 30% probability level.

Picric acid–2,4,6-trichloroaniline (1/1) top

Crystal data top

C₆H₄Cl₃N·C₆H₃N₃O₇	F(000) = 1712
M_r = 425.57	D_x = 1.747 Mg m⁻³
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 1781 reflections
a = 9.2162 (14) Å	θ = 2.5–19.2°
b = 10.0174 (14) Å	µ = 0.61 mm⁻¹
c = 35.051 (5) Å	T = 298 K
V = 3236.0 (8) Å³	Block, red
Z = 8	0.16 × 0.12 × 0.10 mm

Data collection top

Bruker SMART CCD area-detector diffractometer	3186 independent reflections
Radiation source: fine-focus sealed tube	2287 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.076
ϕ and ω scans	θ_max = 26.0°, θ_min = 2.3°
Absorption correction: multi-scan (SADABS; Sheldrick, 1997)	h = −11→11
T_min = 0.908, T_max = 0.941	k = −12→10
19589 measured reflections	l = −41→43

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)] = 0.058	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.120	H atoms treated by a mixture of independent and constrained refinement
S = 1.10	w = 1/[σ²(F_o²) + (0.0381P)² + 1.3007P] where P = (F_o² + 2F_c²)/3
3186 reflections	(Δ/σ)_max = 0.001
244 parameters	Δρ_max = 0.21 e Å⁻³
2 restraints	Δρ_min = −0.27 e Å⁻³

Crystal data top

C₆H₄Cl₃N·C₆H₃N₃O₇	V = 3236.0 (8) Å³
M_r = 425.57	Z = 8
Orthorhombic, Pbca	Mo Kα radiation
a = 9.2162 (14) Å	µ = 0.61 mm⁻¹
b = 10.0174 (14) Å	T = 298 K
c = 35.051 (5) Å	0.16 × 0.12 × 0.10 mm

Data collection top

Bruker SMART CCD area-detector diffractometer	3186 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1997)	2287 reflections with I > 2σ(I)
T_min = 0.908, T_max = 0.941	R_int = 0.076
19589 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.058	2 restraints
wR(F²) = 0.120	H atoms treated by a mixture of independent and constrained refinement
S = 1.10	Δρ_max = 0.21 e Å⁻³
3186 reflections	Δρ_min = −0.27 e Å⁻³
244 parameters

Special details top

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 (Å²) top

	x	y	z	U_iso*/U_eq
C1	0.4507 (4)	0.4557 (3)	0.57639 (9)	0.0373 (8)
C2	0.5792 (3)	0.4955 (3)	0.55888 (10)	0.0396 (8)
C3	0.5881 (4)	0.6056 (4)	0.53560 (10)	0.0422 (9)
H3	0.6760	0.6295	0.5245	0.051*
C4	0.4651 (4)	0.6801 (3)	0.52893 (9)	0.0390 (8)
C5	0.3352 (4)	0.6456 (3)	0.54541 (10)	0.0415 (9)
H5	0.2523	0.6960	0.5408	0.050*
C6	0.3293 (3)	0.5361 (3)	0.56874 (9)	0.0375 (8)
C7	0.4085 (3)	0.4501 (3)	0.70238 (9)	0.0325 (7)
C8	0.5325 (3)	0.3724 (3)	0.70914 (9)	0.0343 (8)
C9	0.6640 (3)	0.3992 (3)	0.69253 (9)	0.0360 (8)
H9	0.7437	0.3447	0.6972	0.043*
C10	0.6760 (4)	0.5082 (3)	0.66889 (9)	0.0379 (8)
C11	0.5597 (4)	0.5899 (3)	0.66136 (9)	0.0379 (8)
H11	0.5694	0.6642	0.6456	0.046*
C12	0.4278 (3)	0.5584 (3)	0.67784 (9)	0.0324 (8)
Cl1	0.73498 (10)	0.40282 (11)	0.56753 (3)	0.0607 (3)
Cl2	0.47396 (11)	0.81912 (11)	0.49911 (3)	0.0592 (3)
Cl3	0.16542 (10)	0.49502 (10)	0.59030 (3)	0.0560 (3)
N1	0.5268 (3)	0.2597 (3)	0.73550 (9)	0.0478 (8)
N2	0.8171 (3)	0.5390 (4)	0.65186 (9)	0.0507 (8)
N3	0.3064 (3)	0.6474 (3)	0.66942 (9)	0.0452 (8)
N4	0.4439 (4)	0.3486 (3)	0.60078 (10)	0.0520 (8)
H4A	0.512 (3)	0.290 (3)	0.6009 (11)	0.062*
H4B	0.359 (2)	0.332 (4)	0.6079 (11)	0.062*
O1	0.2826 (3)	0.4170 (2)	0.71812 (7)	0.0494 (7)
H1A	0.218 (5)	0.479 (4)	0.7114 (11)	0.074*
O2	0.4487 (4)	0.2669 (3)	0.76291 (9)	0.0979 (13)
O3	0.6055 (3)	0.1642 (3)	0.72928 (8)	0.0643 (8)
O4	0.9144 (3)	0.4573 (3)	0.65587 (9)	0.0711 (9)
O5	0.8294 (3)	0.6445 (3)	0.63491 (9)	0.0726 (9)
O6	0.3275 (3)	0.7422 (3)	0.64860 (8)	0.0672 (8)
O7	0.1878 (3)	0.6247 (3)	0.68450 (8)	0.0602 (8)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.041 (2)	0.035 (2)	0.0352 (19)	−0.0034 (16)	0.0003 (15)	−0.0064 (15)
C2	0.0318 (19)	0.042 (2)	0.045 (2)	0.0053 (16)	−0.0046 (15)	−0.0061 (17)
C3	0.0369 (19)	0.045 (2)	0.045 (2)	−0.0084 (17)	0.0048 (16)	−0.0036 (17)
C4	0.0398 (19)	0.037 (2)	0.040 (2)	−0.0048 (17)	−0.0010 (15)	0.0042 (16)
C5	0.0319 (18)	0.045 (2)	0.047 (2)	0.0040 (16)	−0.0042 (16)	0.0025 (17)
C6	0.0333 (18)	0.040 (2)	0.0395 (19)	−0.0019 (16)	0.0051 (15)	−0.0023 (16)
C7	0.0329 (18)	0.0345 (19)	0.0299 (17)	−0.0024 (15)	0.0016 (14)	−0.0052 (14)
C8	0.0383 (18)	0.0281 (19)	0.0365 (18)	0.0010 (15)	0.0009 (15)	0.0055 (14)
C9	0.0330 (17)	0.037 (2)	0.0377 (18)	0.0034 (15)	−0.0012 (15)	−0.0017 (15)
C10	0.0355 (19)	0.039 (2)	0.0392 (19)	−0.0075 (16)	0.0032 (15)	−0.0038 (16)
C11	0.044 (2)	0.032 (2)	0.0385 (19)	−0.0068 (16)	−0.0021 (15)	0.0007 (15)
C12	0.0355 (18)	0.0322 (19)	0.0296 (17)	−0.0002 (15)	−0.0040 (14)	−0.0033 (14)
Cl1	0.0420 (5)	0.0648 (7)	0.0754 (7)	0.0154 (5)	−0.0015 (5)	−0.0019 (5)
Cl2	0.0527 (6)	0.0609 (7)	0.0641 (6)	−0.0095 (5)	−0.0010 (5)	0.0236 (5)
Cl3	0.0402 (5)	0.0565 (6)	0.0712 (7)	−0.0038 (5)	0.0176 (5)	0.0094 (5)
N1	0.0449 (18)	0.050 (2)	0.0481 (19)	0.0053 (16)	0.0021 (15)	0.0120 (15)
N2	0.0446 (19)	0.052 (2)	0.056 (2)	−0.0106 (17)	0.0097 (16)	−0.0038 (17)
N3	0.0457 (19)	0.041 (2)	0.0492 (19)	0.0058 (15)	−0.0081 (15)	0.0014 (15)
N4	0.049 (2)	0.045 (2)	0.062 (2)	0.0031 (16)	0.0048 (18)	0.0101 (17)
O1	0.0370 (14)	0.0485 (17)	0.0626 (17)	0.0027 (12)	0.0115 (12)	0.0103 (13)
O2	0.105 (3)	0.114 (3)	0.075 (2)	0.052 (2)	0.051 (2)	0.0556 (19)
O3	0.0714 (19)	0.0479 (18)	0.073 (2)	0.0191 (15)	0.0092 (15)	0.0161 (14)
O4	0.0390 (16)	0.079 (2)	0.095 (2)	0.0047 (16)	0.0162 (15)	0.0066 (18)
O5	0.070 (2)	0.0587 (19)	0.089 (2)	−0.0161 (16)	0.0300 (16)	0.0133 (17)
O6	0.0654 (19)	0.0548 (18)	0.081 (2)	0.0084 (15)	−0.0129 (15)	0.0285 (16)
O7	0.0393 (15)	0.0554 (18)	0.086 (2)	0.0101 (13)	0.0032 (14)	0.0066 (15)

Geometric parameters (Å, º) top

C1—N4	1.373 (4)	C9—C10	1.374 (4)
C1—C2	1.392 (5)	C9—H9	0.9300
C1—C6	1.404 (5)	C10—C11	1.375 (5)
C2—C3	1.374 (5)	C10—N2	1.464 (4)
C2—Cl1	1.736 (3)	C11—C12	1.382 (4)
C3—C4	1.377 (5)	C11—H11	0.9300
C3—H3	0.9300	C12—N3	1.461 (4)
C4—C5	1.373 (4)	N1—O2	1.202 (4)
C4—Cl2	1.743 (3)	N1—O3	1.221 (4)
C5—C6	1.370 (4)	N2—O5	1.218 (4)
C5—H5	0.9300	N2—O4	1.222 (4)
C6—Cl3	1.739 (3)	N3—O6	1.213 (4)
C7—O1	1.327 (4)	N3—O7	1.235 (4)
C7—C12	1.396 (4)	N4—H4A	0.854 (18)
C7—C8	1.404 (4)	N4—H4B	0.842 (18)
C8—C9	1.371 (4)	O1—H1A	0.89 (4)
C8—N1	1.460 (4)

N4—C1—C2	122.5 (3)	C8—C9—H9	120.6
N4—C1—C6	122.0 (3)	C10—C9—H9	120.6
C2—C1—C6	115.4 (3)	C9—C10—C11	121.7 (3)
C3—C2—C1	122.8 (3)	C9—C10—N2	119.0 (3)
C3—C2—Cl1	118.9 (3)	C11—C10—N2	119.3 (3)
C1—C2—Cl1	118.3 (3)	C10—C11—C12	118.0 (3)
C2—C3—C4	119.1 (3)	C10—C11—H11	121.0
C2—C3—H3	120.4	C12—C11—H11	121.0
C4—C3—H3	120.4	C11—C12—C7	123.2 (3)
C5—C4—C3	120.7 (3)	C11—C12—N3	116.7 (3)
C5—C4—Cl2	119.6 (3)	C7—C12—N3	120.0 (3)
C3—C4—Cl2	119.8 (3)	O2—N1—O3	123.0 (3)
C6—C5—C4	119.1 (3)	O2—N1—C8	118.8 (3)
C6—C5—H5	120.4	O3—N1—C8	118.1 (3)
C4—C5—H5	120.4	O5—N2—O4	124.7 (3)
C5—C6—C1	122.8 (3)	O5—N2—C10	117.7 (3)
C5—C6—Cl3	118.9 (3)	O4—N2—C10	117.6 (3)
C1—C6—Cl3	118.3 (3)	O6—N3—O7	122.9 (3)
O1—C7—C12	124.2 (3)	O6—N3—C12	118.4 (3)
O1—C7—C8	120.2 (3)	O7—N3—C12	118.6 (3)
C12—C7—C8	115.5 (3)	C1—N4—H4A	120 (3)
C9—C8—C7	122.6 (3)	C1—N4—H4B	112 (3)
C9—C8—N1	116.9 (3)	H4A—N4—H4B	123 (4)
C7—C8—N1	120.4 (3)	C7—O1—H1A	108 (3)
C8—C9—C10	118.9 (3)

N4—C1—C2—C3	−177.4 (3)	C8—C9—C10—C11	−0.4 (5)
C6—C1—C2—C3	−0.1 (5)	C8—C9—C10—N2	178.5 (3)
N4—C1—C2—Cl1	1.6 (5)	C9—C10—C11—C12	−1.0 (5)
C6—C1—C2—Cl1	179.0 (2)	N2—C10—C11—C12	−180.0 (3)
C1—C2—C3—C4	−0.4 (5)	C10—C11—C12—C7	1.7 (5)
Cl1—C2—C3—C4	−179.4 (3)	C10—C11—C12—N3	179.8 (3)
C2—C3—C4—C5	0.4 (5)	O1—C7—C12—C11	−179.0 (3)
C2—C3—C4—Cl2	−179.4 (3)	C8—C7—C12—C11	−0.8 (5)
C3—C4—C5—C6	0.2 (5)	O1—C7—C12—N3	2.9 (5)
Cl2—C4—C5—C6	179.9 (3)	C8—C7—C12—N3	−178.8 (3)
C4—C5—C6—C1	−0.7 (5)	C9—C8—N1—O2	144.8 (4)
C4—C5—C6—Cl3	178.7 (3)	C7—C8—N1—O2	−33.6 (5)
N4—C1—C6—C5	178.0 (3)	C9—C8—N1—O3	−32.8 (5)
C2—C1—C6—C5	0.6 (5)	C7—C8—N1—O3	148.8 (3)
N4—C1—C6—Cl3	−1.4 (5)	C9—C10—N2—O5	−171.2 (3)
C2—C1—C6—Cl3	−178.8 (2)	C11—C10—N2—O5	7.8 (5)
O1—C7—C8—C9	177.6 (3)	C9—C10—N2—O4	8.4 (5)
C12—C7—C8—C9	−0.7 (5)	C11—C10—N2—O4	−172.6 (3)
O1—C7—C8—N1	−4.1 (5)	C11—C12—N3—O6	0.4 (4)
C12—C7—C8—N1	177.6 (3)	C7—C12—N3—O6	178.5 (3)
C7—C8—C9—C10	1.4 (5)	C11—C12—N3—O7	−178.0 (3)
N1—C8—C9—C10	−177.0 (3)	C7—C12—N3—O7	0.2 (5)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1A···O7	0.89 (4)	1.76 (4)	2.546 (4)	145 (4)
N4—H4A···Cl1	0.85 (2)	2.62 (4)	2.975 (3)	106 (3)
N4—H4A···O5ⁱ	0.85 (2)	2.39 (2)	3.159 (4)	150 (3)
N4—H4B···Cl3	0.84 (2)	2.49 (3)	2.979 (3)	118 (3)
N4—H4B···O6ⁱⁱ	0.84 (2)	2.40 (2)	3.194 (4)	156 (4)

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

Experimental details

Crystal data
Chemical formula	C₆H₄Cl₃N·C₆H₃N₃O₇
M_r	425.57
Crystal system, space group	Orthorhombic, Pbca
Temperature (K)	298
a, b, c (Å)	9.2162 (14), 10.0174 (14), 35.051 (5)
V (Å³)	3236.0 (8)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.61
Crystal size (mm)	0.16 × 0.12 × 0.10

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1997)
T_min, T_max	0.908, 0.941
No. of measured, independent and observed [I > 2σ(I)] reflections	19589, 3186, 2287
R_int	0.076
(sin θ/λ)_max (Å⁻¹)	0.617

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.058, 0.120, 1.10
No. of reflections	3186
No. of parameters	244
No. of restraints	2
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.21, −0.27

Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 1999), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1A···O7	0.89 (4)	1.76 (4)	2.546 (4)	145 (4)
N4—H4A···Cl1	0.854 (18)	2.62 (4)	2.975 (3)	106 (3)
N4—H4A···O5ⁱ	0.854 (18)	2.39 (2)	3.159 (4)	150 (3)
N4—H4B···Cl3	0.842 (18)	2.49 (3)	2.979 (3)	118 (3)
N4—H4B···O6ⁱⁱ	0.842 (18)	2.40 (2)	3.194 (4)	156 (4)

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

Acknowledgements

The author is grateful to Xiangfan University for financial support.

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