2,5-Dibromo­terephthalic acid dihydrate

Song, G.-L.; Liu, S.; Liu, H.-J.; Zeng, T.; Zhu, H.-J.

doi:10.1107/S1600536808027268

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 64| Part 9| September 2008| Page o1860

doi:10.1107/S1600536808027268

Open

access

2,5-Dibromoterephthalic acid dihydrate

Guang-Liang Song,^a Shan Liu,^a Hua-Jun Liu,^a Tao Zeng ^a and Hong-Jun Zhu ^a ^*

^aDepartment of Applied Chemistry, College of Science, Nanjing University of Technology, Nanjing 210009, People's Republic of China
^*Correspondence e-mail: zhuhj@njut.edu.cn

(Received 16 May 2008; accepted 24 August 2008; online 30 August 2008)

The asymmetric unit of the title compound, C₈H₄Br₂O₄·2H₂O, contains one half-molecule of 2,5-dibromoterephthalic acid (DBTA) and one water molecule. The DBTA molecule is centrosymmetric. In the crystal structure, intermolecular O—H⋯O hydrogen bonds link the molecules, forming a three-dimensional framework.

Related literature

For general background, see: Yao & Tour (1999 ). For a related structure, see: Singh & Bedi (1957 ).

Experimental

Crystal data

C₈H₄Br₂O₄·2H₂O
M_r = 359.94
Monoclinic, P 2₁ /c
a = 10.670 (2) Å
b = 7.413 (1) Å
c = 7.074 (1) Å
β = 92.74 (3)°
V = 558.89 (15) Å³
Z = 2
Mo Kα radiation
μ = 7.26 mm⁻¹
T = 293 (2) K
0.10 × 0.10 × 0.08 mm

Data collection

Enraf–Nonius CAD-4 diffractometer
Absorption correction: ψ scan (North et al., 1968 ) T_min = 0.530, T_max = 0.594 (expected range = 0.499–0.559)
1003 measured reflections
1003 independent reflections
763 reflections with I > 2σ(I)
3 standard reflections every 200 reflections intensity decay: none

Refinement

R[F² > 2σ(F²)] = 0.048
wR(F²) = 0.117
S = 1.05
1003 reflections
67 parameters
21 restraints
H-atom parameters constrained
Δρ_max = 0.55 e Å⁻³
Δρ_min = −0.70 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
OW—HWA⋯O1ⁱ	0.85	2.11	2.903 (9)	155
OW—HWB⋯O1ⁱⁱ	0.85	2.22	2.944 (9)	142
O2—H2A⋯OW	0.82	1.75	2.566 (8)	177
Symmetry codes: (i) -x, -y, -z+1; (ii) $[-x, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]$ .

Data collection: CAD-4 Software (Enraf–Nonius, 1985 ); cell refinement: CAD-4 Software; data reduction: XCAD4 (Harms & Wocadlo, 1995 ); 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/S1600536808027268/ez2130sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808027268/ez2130Isup2.hkl

checkCIF report

Comment top

2,5-Dibromoterephthalic acid (DBTA) is an important intermediate in the preparation of flame-retardant polymers (Yao et al., 1999). We report herein the crystal structure of the title compound (I).

The asymmetric unit of I (Fig. 1), contains one half of a molecule of 2,5-dibromoterephthalic acid (DBTA), which is related to the other half by a center of symmetry, and one water molecule. Three neighbouring DBTA molecules are linked through one water molecule by intermolecular O—H···O hydrogen bonds, to form a three dimensional framework.

Related literature top

For general background, see: Yao & Tour (1999). For a related structure, see: Singh & Bedi (1957).

Experimental top

The title compound was prepared according to the method described by Singh & Bedi (1957). Crystals of (I) suitable for X-ray analysis were obtained by dissolving DBTA (2.0 g) in water (80 ml) and evaporating slowly at room temperature for about 15 d.

Computing details top

Data collection: CAD-4 Software (Enraf–Nonius, 1985); cell refinement: CAD-4 Software (Enraf–Nonius, 1985); data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXS97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

Fig. 1. The molecular structure of (I), showing the atom labelling scheme. Anisotropic displacement parameters are shown at the 50% probability level.

2,5-Dibromoterephthalic acid dihydrate top

Crystal data top

C₈H₄Br₂O₄·2H₂O	F(000) = 348
M_r = 359.94	D_x = 2.139 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
a = 10.670 (2) Å	Cell parameters from 25 reflections
b = 7.413 (1) Å	θ = 10–13°
c = 7.074 (1) Å	µ = 7.26 mm⁻¹
β = 92.74 (3)°	T = 293 K
V = 558.89 (15) Å³	Block, colorless
Z = 2	0.10 × 0.10 × 0.08 mm

Data collection top

Enraf–Nonius CAD-4 diffractometer	763 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.000
Graphite monochromator	θ_max = 25.2°, θ_min = 1.9°
ω/2θ scans	h = −12→12
Absorption correction: ψ scan (North et al., 1968)	k = 0→8
T_min = 0.530, T_max = 0.594	l = 0→8
1003 measured reflections	3 standard reflections every 200 reflections
1003 independent reflections	intensity decay: none

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)] = 0.048	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.117	H-atom parameters constrained
S = 1.05	w = 1/[σ²(F_o²) + (0.06P)² + 1.5P] where P = (F_o² + 2F_c²)/3
1003 reflections	(Δ/σ)_max < 0.001
67 parameters	Δρ_max = 0.55 e Å⁻³
21 restraints	Δρ_min = −0.70 e Å⁻³

Crystal data top

C₈H₄Br₂O₄·2H₂O	V = 558.89 (15) Å³
M_r = 359.94	Z = 2
Monoclinic, P2₁/c	Mo Kα radiation
a = 10.670 (2) Å	µ = 7.26 mm⁻¹
b = 7.413 (1) Å	T = 293 K
c = 7.074 (1) Å	0.10 × 0.10 × 0.08 mm
β = 92.74 (3)°

Data collection top

Enraf–Nonius CAD-4 diffractometer	763 reflections with I > 2σ(I)
Absorption correction: ψ scan (North et al., 1968)	R_int = 0.000
T_min = 0.530, T_max = 0.594	3 standard reflections every 200 reflections
1003 measured reflections	intensity decay: none
1003 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.048	21 restraints
wR(F²) = 0.117	H-atom parameters constrained
S = 1.05	Δρ_max = 0.55 e Å⁻³
1003 reflections	Δρ_min = −0.70 e Å⁻³
67 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
Br	0.31754 (7)	0.35260 (9)	0.52687 (10)	0.0366 (3)
OW	−0.0069 (5)	−0.2828 (11)	0.7105 (11)	0.093 (3)
HWA	−0.0608	−0.2028	0.6780	0.111*
HWB	−0.0299	−0.3786	0.7651	0.111*
O1	0.1532 (5)	0.0220 (6)	0.5124 (8)	0.0495 (14)
O2	0.2259 (5)	−0.2252 (7)	0.6570 (9)	0.0554 (15)
H2A	0.1515	−0.2402	0.6767	0.083*
C1	0.5431 (6)	0.1725 (10)	0.4729 (9)	0.034
H1A	0.5725	0.2885	0.4518	0.040*
C2	0.4182 (6)	0.1457 (8)	0.5085 (9)	0.0276 (13)
C3	0.3736 (6)	−0.0245 (8)	0.5317 (8)	0.0255 (13)
C4	0.2396 (6)	−0.0748 (9)	0.5662 (9)	0.0314 (15)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br	0.0487 (4)	0.0111 (4)	0.0496 (5)	0.0050 (3)	−0.0007 (3)	0.0002 (3)
OW	0.030 (3)	0.111 (6)	0.139 (7)	0.008 (3)	0.013 (3)	0.073 (5)
O1	0.045 (3)	0.016 (3)	0.087 (4)	−0.004 (2)	−0.002 (3)	0.015 (3)
O2	0.051 (3)	0.028 (3)	0.087 (4)	−0.006 (3)	−0.004 (3)	0.029 (3)
C1	0.034	0.034	0.034	0.000	0.002	0.000
C2	0.043 (3)	0.009 (3)	0.030 (3)	0.002 (3)	−0.009 (3)	0.000 (3)
C3	0.038 (3)	0.013 (3)	0.025 (3)	−0.002 (3)	−0.003 (2)	−0.004 (3)
C4	0.035 (3)	0.022 (3)	0.038 (4)	0.003 (3)	0.004 (3)	0.005 (3)

Geometric parameters (Å, º) top

Br—C2	1.880 (6)	C1—C2	1.383 (8)
OW—HWA	0.8500	C1—C3ⁱ	1.413 (9)
OW—HWB	0.8500	C1—H1A	0.9300
O1—C4	1.215 (8)	C2—C3	1.361 (8)
O2—C4	1.299 (8)	C3—C1ⁱ	1.413 (9)
O2—H2A	0.8200	C3—C4	1.508 (9)

HWA—OW—HWB	120.0	C1—C2—Br	117.0 (5)
C4—O2—H2A	109.5	C2—C3—C1ⁱ	119.5 (6)
C2—C1—C3ⁱ	120.4 (6)	C2—C3—C4	126.0 (6)
C2—C1—H1A	119.8	C1ⁱ—C3—C4	114.5 (5)
C3ⁱ—C1—H1A	119.8	O1—C4—O2	124.1 (6)
C3—C2—C1	120.1 (6)	O1—C4—C3	121.0 (6)
C3—C2—Br	122.9 (5)	O2—C4—C3	115.0 (6)

C3ⁱ—C1—C2—C3	−2.7 (10)	Br—C2—C3—C4	2.8 (9)
C3ⁱ—C1—C2—Br	176.2 (5)	C2—C3—C4—O1	26.1 (10)
C1—C2—C3—C1ⁱ	2.7 (10)	C1ⁱ—C3—C4—O1	−154.9 (6)
Br—C2—C3—C1ⁱ	−176.2 (5)	C2—C3—C4—O2	−153.4 (7)
C1—C2—C3—C4	−178.3 (6)	C1ⁱ—C3—C4—O2	25.6 (8)

Symmetry code: (i) −x+1, −y, −z+1.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
OW—HWA···O1ⁱⁱ	0.85	2.11	2.903 (9)	155
OW—HWB···O1ⁱⁱⁱ	0.85	2.22	2.944 (9)	142
O2—H2A···OW	0.82	1.75	2.566 (8)	177

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

Experimental details

Crystal data
Chemical formula	C₈H₄Br₂O₄·2H₂O
M_r	359.94
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	10.670 (2), 7.413 (1), 7.074 (1)
β (°)	92.74 (3)
V (Å³)	558.89 (15)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	7.26
Crystal size (mm)	0.10 × 0.10 × 0.08

Data collection
Diffractometer	Enraf–Nonius CAD-4 diffractometer
Absorption correction	ψ scan (North et al., 1968)
T_min, T_max	0.530, 0.594
No. of measured, independent and observed [I > 2σ(I)] reflections	1003, 1003, 763
R_int	0.000
(sin θ/λ)_max (Å⁻¹)	0.599

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.048, 0.117, 1.05
No. of reflections	1003
No. of parameters	67
No. of restraints	21
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.55, −0.70

Computer programs: CAD-4 Software (Enraf–Nonius, 1985), XCAD4 (Harms & Wocadlo, 1995), SHELXS97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Selected geometric parameters (Å, º) top

Br—C2	1.880 (6)	O2—C4	1.299 (8)
O1—C4	1.215 (8)

C3—C2—Br	122.9 (5)	O1—C4—C3	121.0 (6)
C1—C2—Br	117.0 (5)	O2—C4—C3	115.0 (6)
O1—C4—O2	124.1 (6)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
OW—HWA···O1ⁱ	0.8500	2.1100	2.903 (9)	155.00
OW—HWB···O1ⁱⁱ	0.8500	2.2200	2.944 (9)	142.00
O2—H2A···OW	0.8200	1.7500	2.566 (8)	177.00

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

Acknowledgements

The authors thank the Center of Testing and Analysis, Nanjing University, for support.

References

Enraf–Nonius (1985). CAD-4 Software. Enraf–Nonius, Delft, The Netherlands. Google Scholar
Harms, K. & Wocadlo, S. (1995). XCAD4. University of Marburg, Germany. Google Scholar
North, A. C. T., Phillips, D. C. & Mathews, F. S. (1968). Acta Cryst. A24, 351–359. CrossRef IUCr Journals Web of Science Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Singh, T. & Bedi, S. N. (1957). J. Indian Chem. Soc. 34, 321–323. CAS Google Scholar
Yao, Y. X. & Tour, J. M. (1999). Macromolecules, 32, 2455–2461. Web of Science CrossRef CAS Google Scholar