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Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890

3-Bromo­anilinium picrate

aCollege of Chemical Engineering and Technology, Wuhan University of Science and Technology, Wuhan 430081, People's Republic of China, and bSchool of Medicine, Wuhan University of Science and Technology, Wuhan 430081, People's Republic of China
*Correspondence e-mail: yanwatercn@wust.edu.cn

(Received 5 November 2009; accepted 14 November 2009; online 25 November 2009)

In the title compound, C6H7BrN+·C6H2N3O7, the O atoms of two of the nitro groups are disordered over two sites, the ratios of the refined occupancies being 0.72 (6):0.28 (6) and 0.74 (5):0.26 (5). In the crystal structure, the anions and cations are linked via inter­molecular N—H⋯O hydrogen bonds into chains along [100]. Further stabilization is provided by weak inter­molecular C—H⋯O hydrogen bonds.

Related literature

For background information on the crystallization of ammonium salts with picrate derivatives, see: Harrison et al. (2007[Harrison, W. T. A., Ashok, M. A., Yathirajan, H. S. & Narayana Achar, B. (2007). Acta Cryst. E63, o3277.]); Pascard et al. (1982[Pascard, C., Riche, C., Cesario, M., Kotzyba-Hibert, F. & Lehn, J. M. (1982). Chem. Commun. pp. 557-558.]); Pearson et al. (2007[Pearson, W. H., Kropf, J. E., Choy, A. L., Lee, I. Y. & Kampf, J. W. (2007). J. Org. Chem. 72, 4135-4148.]); Wang et al. (2003[Wang, Q. R., Li, Z., Yang, H. Y., Li, F., Ding, Z. B. & Tao, F. G. (2003). Synthesis, pp. 1231-1235.]).

[Scheme 1]

Experimental

Crystal data
  • C6H7BrN+·C6H2N3O7

  • Mr = 401.14

  • Triclinic, [P \overline 1]

  • a = 4.3515 (3) Å

  • b = 12.0757 (8) Å

  • c = 14.0592 (9) Å

  • α = 87.783 (1)°

  • β = 85.945 (1)°

  • γ = 80.533 (1)°

  • V = 726.61 (8) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 2.88 mm−1

  • T = 298 K

  • 0.16 × 0.12 × 0.10 mm

Data collection
  • Bruker SMART APEX CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.646, Tmax = 0.762

  • 4689 measured reflections

  • 2818 independent reflections

  • 2225 reflections with I > 2σ(I)

  • Rint = 0.090

Refinement
  • R[F2 > 2σ(F2)] = 0.047

  • wR(F2) = 0.123

  • S = 0.96

  • 2818 reflections

  • 264 parameters

  • 15 restraints

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.69 e Å−3

  • Δρmin = −0.59 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1C⋯O7i 0.859 (10) 2.50 (3) 2.966 (12) 115 (3)
N1—H1C⋯O1i 0.859 (10) 1.934 (14) 2.775 (4) 166 (3)
N1—H1A⋯O1 0.856 (10) 1.958 (17) 2.766 (4) 157 (3)
N1—H1B⋯O6ii 0.862 (10) 2.28 (2) 3.047 (12) 148 (3)
C11—H11⋯O5iii 0.93 2.45 3.296 (4) 152
C4—H4⋯O3iv 0.93 2.57 3.273 (7) 133
Symmetry codes: (i) x-1, y, z; (ii) -x+2, -y+2, -z; (iii) -x+3, -y+1, -z; (iv) -x, -y+2, -z+1.

Data collection: SMART (Bruker, 2001[Bruker (2001). SMART and SAINT-Plus. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT-Plus (Bruker, 2001[Bruker (2001). SMART and SAINT-Plus. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: PLATON.

Supporting information


Comment top

The interaction of picric acid and amines has been widely studied and salt formation takes place readily with very low activation energy. Ammonium salts are easy to crystallize and purify when picrate derivatives are present (Pascard et al.,1982;Wang et al.,2003; Pearson et al., 2007; Harrison et al., 2007). Herein, we report the crystal structure of the title compound.

In the title compound, the proton has been transferred from the phenolic hydroxylic group to the amine group, resulting in an 1:1 organic salt (Fig.1). In the crystal structure, the molecular components are linked together by intermolecular N—H···O hydrogen bonds forming a one-dimensional chain running parallel to [100]. Adjacent chains are further linked by two weak intermolecular C—H···O hydrogen bonds (see Fig. 2).

Related literature top

For background information on the crystallization of ammonium salts with picrate derivatives, see: Harrison et al. (2007); Pascard et al. (1982); Pearson et al. (2007); Wang et al. (2003).

Experimental top

Picric acid (0.6873 g, 3 mmol) and 3-Bromoaniline (0.5161 g, 3 mmol) were mixed in 10 ml ethanol. The mixture was kept at room temperature for ten days. Yellow block-shaped crystals suitable for the single-crystal X-ray diffraction were collected from the bottom of the vessel.

Refinement top

In the picrate anion two of the nitro groups oxygen atoms are disordered over two positions with refined occupancies 0.72 (6):0.28 (6) and 0.74 (5):0.26 (5) for O2/O3:O2'/O3' and O6/O7:O6'/O7', respectively.

The carbon-bound hydrogen atoms were placed in ideal positions with C—H=0.93Å and Uiso(H) = 1.2Ueq(C). H1A, H1B and H1C atoms were located in a difference map and refined with the restraint of N—H = 0.86 (1)Å and Uiso(H) = 1.2Ueq(N).

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT-Plus (Bruker, 2001); data reduction: SAINT-Plus (Bruker, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The asymmetric unit with the atom-numbering scheme. The displacement ellipsoids are drawn at the 30% probability level. A hydrogen bond is shown by a dashed line. The minor components of disorder are indicated by primed atom labels.
[Figure 2] Fig. 2. Part of the crystal structure with hydrogen bonds shown as dashed lines.
3-Bromoanilinium picrate top
Crystal data top
C6H7BrN+·C6H2N3O7Z = 2
Mr = 401.14F(000) = 400
Triclinic, P1Dx = 1.833 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 4.3515 (3) ÅCell parameters from 2179 reflections
b = 12.0757 (8) Åθ = 2.3–27.6°
c = 14.0592 (9) ŵ = 2.88 mm1
α = 87.783 (1)°T = 298 K
β = 85.945 (1)°Block, yellow
γ = 80.533 (1)°0.16 × 0.12 × 0.10 mm
V = 726.61 (8) Å3
Data collection top
Bruker SMART APEX CCD
diffractometer
2818 independent reflections
Radiation source: fine focus sealed Siemens Mo tube2225 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.090
0.3° wide ω exposures scansθmax = 26.0°, θmin = 2.2°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 55
Tmin = 0.646, Tmax = 0.762k = 1412
4689 measured reflectionsl = 1716
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.047Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.123H atoms treated by a mixture of independent and constrained refinement
S = 0.96 w = 1/[σ2(Fo2) + (0.0686P)2]
where P = (Fo2 + 2Fc2)/3
2818 reflections(Δ/σ)max < 0.001
264 parametersΔρmax = 0.69 e Å3
15 restraintsΔρmin = 0.59 e Å3
Crystal data top
C6H7BrN+·C6H2N3O7γ = 80.533 (1)°
Mr = 401.14V = 726.61 (8) Å3
Triclinic, P1Z = 2
a = 4.3515 (3) ÅMo Kα radiation
b = 12.0757 (8) ŵ = 2.88 mm1
c = 14.0592 (9) ÅT = 298 K
α = 87.783 (1)°0.16 × 0.12 × 0.10 mm
β = 85.945 (1)°
Data collection top
Bruker SMART APEX CCD
diffractometer
2818 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
2225 reflections with I > 2σ(I)
Tmin = 0.646, Tmax = 0.762Rint = 0.090
4689 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.04715 restraints
wR(F2) = 0.123H atoms treated by a mixture of independent and constrained refinement
S = 0.96Δρmax = 0.69 e Å3
2818 reflectionsΔρmin = 0.59 e Å3
264 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
xyzUiso*/UeqOcc. (<1)
Br10.31978 (9)1.44651 (3)0.38403 (3)0.0620 (2)
C10.2439 (7)1.1358 (3)0.2852 (2)0.0365 (6)
C20.3254 (7)1.2405 (3)0.2916 (2)0.0400 (7)
H20.44881.26940.24320.048*
C30.2197 (7)1.3015 (3)0.3716 (2)0.0418 (7)
C40.0376 (8)1.2589 (3)0.4453 (2)0.0488 (8)
H40.03121.30060.49920.059*
C50.0383 (8)1.1533 (3)0.4364 (2)0.0500 (8)
H50.15931.12360.48510.060*
C60.0623 (8)1.0912 (3)0.3568 (2)0.0451 (7)
H60.00901.02040.35120.054*
C70.9423 (7)0.8220 (3)0.1767 (2)0.0376 (7)
C80.7948 (7)0.7451 (3)0.2374 (2)0.0401 (7)
C90.8229 (8)0.6320 (3)0.2218 (2)0.0432 (7)
H90.72000.58620.26320.052*
C101.0069 (8)0.5873 (3)0.1436 (2)0.0434 (7)
C111.1497 (7)0.6552 (3)0.0790 (2)0.0433 (7)
H111.26600.62530.02530.052*
C121.1162 (7)0.7672 (3)0.0960 (2)0.0398 (7)
N10.3525 (7)1.0693 (2)0.20133 (19)0.0421 (6)
H1A0.520 (5)1.025 (3)0.215 (2)0.051*
H1B0.400 (8)1.110 (3)0.1527 (17)0.051*
H1C0.229 (7)1.025 (2)0.187 (2)0.051*
N20.6000 (7)0.7845 (3)0.32217 (19)0.0484 (7)
N31.0392 (7)0.4679 (3)0.1282 (2)0.0503 (7)
N41.2620 (7)0.8348 (2)0.02367 (18)0.0490 (7)
O10.9193 (5)0.9265 (2)0.18883 (16)0.0489 (6)
O20.623 (5)0.8764 (8)0.3531 (10)0.066 (3)0.72 (6)
O30.419 (6)0.7259 (14)0.3589 (15)0.081 (4)0.72 (6)
O2'0.506 (13)0.8824 (11)0.334 (2)0.074 (8)0.28 (6)
O3'0.555 (13)0.7092 (12)0.3811 (14)0.058 (8)0.28 (6)
O40.8643 (8)0.4144 (2)0.1743 (2)0.0706 (8)
O51.2388 (7)0.4267 (2)0.0683 (2)0.0661 (7)
O61.223 (5)0.8179 (12)0.0605 (4)0.068 (3)0.74 (5)
O71.419 (3)0.9014 (12)0.0496 (6)0.064 (3)0.74 (5)
O6'1.340 (11)0.798 (3)0.0553 (15)0.073 (8)0.26 (5)
O7'1.27 (2)0.935 (3)0.039 (3)0.099 (14)0.26 (5)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.0788 (3)0.0419 (2)0.0677 (3)0.01847 (19)0.0063 (2)0.01619 (18)
C10.0392 (15)0.0353 (16)0.0344 (15)0.0054 (13)0.0003 (12)0.0009 (12)
C20.0447 (16)0.0371 (17)0.0382 (15)0.0100 (14)0.0045 (13)0.0000 (13)
C30.0465 (17)0.0359 (16)0.0429 (16)0.0051 (14)0.0051 (13)0.0030 (13)
C40.059 (2)0.050 (2)0.0356 (16)0.0058 (16)0.0021 (14)0.0039 (14)
C50.062 (2)0.050 (2)0.0379 (17)0.0161 (17)0.0096 (15)0.0034 (15)
C60.0538 (18)0.0408 (18)0.0416 (17)0.0132 (15)0.0024 (14)0.0018 (14)
C70.0412 (15)0.0368 (17)0.0363 (15)0.0098 (13)0.0032 (12)0.0045 (12)
C80.0424 (16)0.0492 (19)0.0296 (14)0.0107 (14)0.0006 (12)0.0048 (13)
C90.0506 (18)0.0424 (18)0.0389 (16)0.0159 (15)0.0021 (13)0.0025 (14)
C100.0568 (19)0.0354 (17)0.0389 (16)0.0107 (15)0.0024 (14)0.0016 (13)
C110.0495 (18)0.0429 (18)0.0375 (16)0.0091 (15)0.0028 (13)0.0048 (14)
C120.0448 (16)0.0412 (18)0.0347 (15)0.0139 (14)0.0033 (12)0.0007 (13)
N10.0517 (16)0.0350 (15)0.0405 (14)0.0121 (12)0.0048 (12)0.0042 (11)
N20.0560 (17)0.0534 (19)0.0354 (14)0.0103 (15)0.0051 (12)0.0044 (14)
N30.0647 (18)0.0412 (16)0.0463 (15)0.0100 (14)0.0090 (14)0.0012 (13)
N40.0648 (18)0.0423 (17)0.0408 (16)0.0171 (14)0.0113 (13)0.0026 (12)
O10.0499 (13)0.0405 (13)0.0580 (14)0.0141 (10)0.0069 (10)0.0112 (11)
O20.092 (7)0.048 (4)0.053 (4)0.007 (3)0.021 (4)0.012 (2)
O30.078 (8)0.106 (5)0.067 (6)0.051 (5)0.035 (6)0.029 (4)
O2'0.079 (18)0.069 (10)0.054 (11)0.028 (8)0.028 (10)0.016 (7)
O3'0.071 (16)0.066 (8)0.043 (7)0.032 (8)0.010 (8)0.012 (5)
O40.099 (2)0.0506 (16)0.0676 (17)0.0332 (16)0.0046 (15)0.0009 (13)
O50.0760 (18)0.0444 (15)0.0747 (17)0.0016 (13)0.0045 (14)0.0115 (13)
O60.106 (8)0.061 (5)0.040 (3)0.029 (5)0.015 (3)0.006 (2)
O70.067 (4)0.071 (5)0.064 (3)0.039 (4)0.003 (3)0.002 (3)
O6'0.097 (18)0.044 (9)0.068 (11)0.001 (11)0.047 (9)0.013 (7)
O7'0.14 (4)0.084 (13)0.085 (14)0.067 (17)0.039 (19)0.019 (12)
Geometric parameters (Å, º) top
Br1—C31.890 (3)C10—C111.383 (4)
C1—C21.376 (4)C10—N31.449 (4)
C1—C61.382 (4)C11—C121.365 (5)
C1—N11.459 (4)C11—H110.9300
C2—C31.377 (4)C12—N41.455 (4)
C2—H20.9300N1—H1A0.856 (10)
C3—C41.394 (4)N1—H1B0.862 (10)
C4—C51.382 (5)N1—H1C0.859 (10)
C4—H40.9300N2—O2'1.200 (10)
C5—C61.377 (5)N2—O31.218 (5)
C5—H50.9300N2—O21.229 (6)
C6—H60.9300N2—O3'1.237 (9)
C7—O11.266 (4)N3—O41.215 (4)
C7—C81.435 (4)N3—O51.223 (4)
C7—C121.439 (4)N4—O6'1.218 (10)
C8—C91.375 (5)N4—O71.220 (6)
C8—N21.461 (4)N4—O61.236 (6)
C9—C101.386 (4)N4—O7'1.240 (10)
C9—H90.9300
C2—C1—C6121.6 (3)C12—C11—H11120.7
C2—C1—N1119.5 (2)C10—C11—H11120.7
C6—C1—N1118.8 (3)C11—C12—C7125.2 (3)
C1—C2—C3118.4 (3)C11—C12—N4115.8 (3)
C1—C2—H2120.8C7—C12—N4118.9 (3)
C3—C2—H2120.8C1—N1—H1A108 (3)
C2—C3—C4121.5 (3)C1—N1—H1B112 (2)
C2—C3—Br1120.4 (2)H1A—N1—H1B107 (3)
C4—C3—Br1118.1 (2)C1—N1—H1C114 (2)
C5—C4—C3118.5 (3)H1A—N1—H1C104 (4)
C5—C4—H4120.8H1B—N1—H1C111 (3)
C3—C4—H4120.8O2'—N2—O3111.6 (16)
C6—C5—C4121.0 (3)O3—N2—O2122.5 (6)
C6—C5—H5119.5O2'—N2—O3'123.8 (14)
C4—C5—H5119.5O2—N2—O3'117.4 (10)
C5—C6—C1119.0 (3)O2'—N2—C8121.9 (12)
C5—C6—H6120.5O3—N2—C8119.0 (4)
C1—C6—H6120.5O2—N2—C8118.5 (5)
O1—C7—C8125.7 (3)O3'—N2—C8114.2 (12)
O1—C7—C12122.5 (3)O4—N3—O5123.5 (3)
C8—C7—C12111.8 (3)O4—N3—C10118.4 (3)
C9—C8—C7124.2 (3)O5—N3—C10118.1 (3)
C9—C8—N2115.3 (3)O6'—N4—O7114.7 (18)
C7—C8—N2120.5 (3)O7—N4—O6124.7 (6)
C8—C9—C10119.1 (3)O6'—N4—O7'119.8 (15)
C8—C9—H9120.5O6—N4—O7'113 (2)
C10—C9—H9120.5O6'—N4—C12120.1 (15)
C11—C10—C9121.1 (3)O7—N4—C12118.3 (4)
C11—C10—N3120.0 (3)O6—N4—C12117.0 (6)
C9—C10—N3118.9 (3)O7'—N4—C12119.6 (11)
C12—C11—C10118.5 (3)C7—O1—H1A123.4 (12)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1C···O7i0.86 (1)2.50 (3)2.966 (12)115 (3)
N1—H1C···O1i0.86 (1)1.93 (1)2.775 (4)166 (3)
N1—H1A···O10.86 (1)1.96 (2)2.766 (4)157 (3)
N1—H1B···O6ii0.86 (1)2.28 (2)3.047 (12)148 (3)
C11—H11···O5iii0.932.453.296 (4)152
C4—H4···O3iv0.932.573.273 (7)133
Symmetry codes: (i) x1, y, z; (ii) x+2, y+2, z; (iii) x+3, y+1, z; (iv) x, y+2, z+1.

Experimental details

Crystal data
Chemical formulaC6H7BrN+·C6H2N3O7
Mr401.14
Crystal system, space groupTriclinic, P1
Temperature (K)298
a, b, c (Å)4.3515 (3), 12.0757 (8), 14.0592 (9)
α, β, γ (°)87.783 (1), 85.945 (1), 80.533 (1)
V3)726.61 (8)
Z2
Radiation typeMo Kα
µ (mm1)2.88
Crystal size (mm)0.16 × 0.12 × 0.10
Data collection
DiffractometerBruker SMART APEX CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.646, 0.762
No. of measured, independent and
observed [I > 2σ(I)] reflections
4689, 2818, 2225
Rint0.090
(sin θ/λ)max1)0.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.047, 0.123, 0.96
No. of reflections2818
No. of parameters264
No. of restraints15
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.69, 0.59

Computer programs: SMART (Bruker, 2001), SAINT-Plus (Bruker, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1C···O7i0.859 (10)2.50 (3)2.966 (12)115 (3)
N1—H1C···O1i0.859 (10)1.934 (14)2.775 (4)166 (3)
N1—H1A···O10.856 (10)1.958 (17)2.766 (4)157 (3)
N1—H1B···O6ii0.862 (10)2.28 (2)3.047 (12)148 (3)
C11—H11···O5iii0.932.453.296 (4)151.8
C4—H4···O3iv0.932.573.273 (7)133.0
Symmetry codes: (i) x1, y, z; (ii) x+2, y+2, z; (iii) x+3, y+1, z; (iv) x, y+2, z+1.
 

Acknowledgements

We thank Wuhan University of Science and Technology for supporting this study.

References

First citationBruker (2001). SMART and SAINT-Plus. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
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