2,3-Di­bromo-3-phenyl­propanoic acid: a monoclinic polymorph

Howard, T.R.; Mendez-deMello, K.A.; Cardenas, A.J.P.

doi:10.1107/S241431461601885X

organic compounds

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ISSN: 2414-3146

Volume 1| Part 11| November 2016| x161885

https://doi.org/10.1107/S241431461601885X

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2,3-Dibromo-3-phenylpropanoic acid: a monoclinic polymorph

Trent R. Howard,^a Kaleh A. Mendez-deMello ^a and Allan Jay P. Cardenas ^a ^*

^a325 Science Center, Fredonia State University of New York, Fredonia 14063, USA
^*Correspondence e-mail: allan.cardenas@fredonia.edu

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 14 November 2016; accepted 24 November 2016; online 29 November 2016)

Bromination of trans-cinnamic acid resulted in the formation of 2,3-dibromo-3-phenylpropanoic acid, C₉H₈Br₂O₂. Crystallization from ethanol–water (1:1) gave crystals of different shapes. One is in the form of rods, that crystallized as the orthorhombic polymorph (Pnma), and whose structure has been described [Thong et al. (2008 ). Acta Cryst. E64, o1946]. The other are thin plate-like crystals which are the monoclinic polymorph (P2₁/n). The structure of this monoclinic polymorph is similar to that of the orthorhombic polymorph; here the aliphatic C atoms are disordered over three sets of sites (occupancy ratio 0.5:0.25:0.25). In the crystal, molecules are linked by pairs of O—H⋯O hydrogen bonds, forming inversion dimers with an R₂²(8) ring motif. The dimers are linked by weak C—H⋯Br hydrogen bonds, forming chains propagating along the a-axis direction.

Keywords: crystal structure; bromination; hydrogen bonding; inversion dimers.

CCDC reference: 1519137

Structure description

Addition of bromine in glacial acetic acid to trans-cinnamic acid yielded mostly erythro-2,3-dibromo-3-phenylpropanoic acid. Crystallization from ethanol–water (1:1, v:v), gave different-shaped crystals that proved to be two polymorphs of the title compound. The rod-shaped crystalline material was shown to be the orthorhombic polymorph (Pnma), reported on by Thong et al. (2008). The thin plate-like crystals have a monoclinic unit cell (P2₁/n), and herein we report on the crystal structure.

The alipathic carbons, C1 and C2, are split over three positions, and were assigned an occupancy ratio of 0.5:0.25:0.25. The molecular structure of the major component is illustrated in Fig. 1.

Figure 1
A view of the molecular structure of the title monoclinic polymorph, with the atom labelling and 50% probability displacement ellipsoids. Only the major component of the disordered aliphatic C atoms (C1 and C2) is shown.

In the crystal, molecules are linked by pairs of O—H⋯O hydrogen bonds, forming a classical carboxylic acid inversion dimer with an $[R_{2}^{2}]$ (8) ring motif (Table 1 and Fig. 2). Neighboring dimers are linked by weak C—H⋯Br hydrogen bonds, forming chains propagating along the a-axis direction (Table 1 and Fig. 2).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H2O⋯O1ⁱ	0.84	1.81	2.638 (5)	167
C1—H1⋯Br2ⁱⁱ	1.00	2.96	3.845 (6)	148
C2—H2⋯Br1ⁱⁱⁱ	1.00	3.01	3.884 (7)	147
Symmetry codes: (i) -x+1, -y+1, -z+2; (ii) x+1, y, z; (iii) x-1, y, z.

Figure 2
A view along the c axis of the crystal packing of the title monoclinic polymorph. The hydrogen bonds are shown as dashed lines (see Table 1

), and only the major component of the disordered aliphatic C atoms (C1 and C2) is shown.

Synthesis and crystallization

Excess bromine in glacial acetic acid was added to trans-cinnamic acid. The crude product was precipitated by addition of water. The crude product was recrystallized from a 1:1 ethanol–water solution at 277 K. Both colorless rod-like and plate-like crystals of the compound were obtained. The reaction scheme is shown in Fig. 3.

Figure 3
Reaction scheme.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2. The alipathic carbons, C1 and C2, are split over three positions, and were assigned an occupancy ratio of 0.5:0.25:0.25.

Table 2
Experimental details

Crystal data
Chemical formula	C₉H₈Br₂O₂
M_r	307.97
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	106
a, b, c (Å)	5.5382 (2), 28.8640 (13), 6.6112 (3)
β (°)	111.935 (1)
V (Å³)	980.32 (7)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	8.23
Crystal size (mm)	0.48 × 0.35 × 0.09

Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2015 )
T_min, T_max	0.456, 0.746
No. of measured, independent and observed [I > 2σ(I)] reflections	32878, 2452, 2302
R_int	0.040
(sin θ/λ)_max (Å⁻¹)	0.668

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.033, 0.093, 1.07
No. of reflections	2452
No. of parameters	126
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.04, −1.02
Computer programs: APEX2 and SAINT (Bruker, 2015), olex2.solve (Bourhis et al., 2015 ), SHELXL2016 (Sheldrick, 2015 ), Mercury (Macrae et al., 2008 ), OLEX2 (Dolomanov et al., 2009 ) and SHELXL2016 (Sheldrick, 2015).

Structural data

CCDC reference: 1519137

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S241431461601885X/su4098sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S241431461601885X/su4098Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S241431461601885X/su4098Isup3.cml

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2015); cell refinement: SAINT (Bruker, 2015); data reduction: SAINT (Bruker, 2015); program(s) used to solve structure: olex2.solve (Bourhis et al., 2015); program(s) used to refine structure: SHELXL2016 (Sheldrick, 2015); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009) and SHELXL2016 (Sheldrick, 2015).

2,3-Dibromo-3-phenylpropanoic acid top

Crystal data top

C₉H₈Br₂O₂	F(000) = 592
M_r = 307.97	D_x = 2.087 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
a = 5.5382 (2) Å	Cell parameters from 9931 reflections
b = 28.8640 (13) Å	θ = 3.4–28.3°
c = 6.6112 (3) Å	µ = 8.23 mm⁻¹
β = 111.935 (1)°	T = 106 K
V = 980.32 (7) Å³	Plate, colorless
Z = 4	0.48 × 0.35 × 0.09 mm

Data collection top

Bruker APEXII CCD diffractometer	2302 reflections with I > 2σ(I)
φ and ω scans	R_int = 0.040
Absorption correction: multi-scan (SADABS; Bruker, 2015)	θ_max = 28.3°, θ_min = 2.8°
T_min = 0.456, T_max = 0.746	h = −7→6
32878 measured reflections	k = −38→38
2452 independent reflections	l = −8→8

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.033	H-atom parameters constrained
wR(F²) = 0.093	w = 1/[σ²(F_o²) + (0.0498P)² + 3.0256P] where P = (F_o² + 2F_c²)/3
S = 1.07	(Δ/σ)_max = 0.001
2452 reflections	Δρ_max = 1.04 e Å⁻³
126 parameters	Δρ_min = −1.02 e Å⁻³
0 restraints	Extinction correction: SHELXL2016 (Sheldrick, 2015), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0063 (9)

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

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

	x	y	z	U_iso*/U_eq	Occ. (<1)
Br1	0.72796 (6)	0.36584 (2)	0.82102 (5)	0.02215 (13)
Br2	−0.02058 (6)	0.43970 (2)	0.37555 (5)	0.02384 (13)
C3	0.2346 (10)	0.34824 (16)	0.4013 (8)	0.0418 (10)
C4	0.0636 (8)	0.31343 (15)	0.4024 (6)	0.0327 (8)
H4	−0.021097	0.314523	0.503558	0.039*
C5	0.0162 (7)	0.27744 (12)	0.2582 (6)	0.0220 (6)
H5	−0.105009	0.254060	0.257170	0.026*
C6	0.1431 (6)	0.27480 (12)	0.1139 (5)	0.0206 (6)
H6	0.110182	0.249474	0.015500	0.025*
C7	0.3178 (7)	0.30891 (13)	0.1124 (6)	0.0231 (7)
H7	0.406474	0.306975	0.014352	0.028*
C8	0.3625 (8)	0.34602 (14)	0.2555 (7)	0.0352 (9)
H8	0.480065	0.369870	0.254135	0.042*
C9	0.4667 (13)	0.4536 (2)	0.7928 (9)	0.0596 (15)
O1	0.3550 (8)	0.44829 (11)	0.9260 (7)	0.0511 (9)
O2	0.5956 (10)	0.48698 (15)	0.7794 (6)	0.0652 (12)
H2O	0.622278	0.504415	0.887335	0.098*
C1	0.4884 (13)	0.4126 (2)	0.6445 (10)	0.0191 (7)	0.5
H1	0.546193	0.424225	0.527342	0.023*	0.5
C2	0.2257 (13)	0.3899 (2)	0.5471 (11)	0.0191 (7)	0.5
H2	0.170807	0.378764	0.666760	0.023*	0.5
C1A	0.339 (3)	0.4271 (5)	0.554 (2)	0.0191 (7)	0.25
H1A	0.450625	0.432294	0.467135	0.023*	0.25
C2A	0.353 (3)	0.3769 (5)	0.622 (2)	0.0191 (7)	0.25
H2A	0.239337	0.372327	0.707530	0.023*	0.25
C1B	0.300 (3)	0.4015 (5)	0.477 (2)	0.0191 (7)	0.25
H1B	0.440311	0.414737	0.433276	0.023*	0.25
C2B	0.379 (3)	0.3982 (5)	0.715 (2)	0.0191 (7)	0.25
H2B	0.246721	0.384549	0.766877	0.023*	0.25

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.02210 (19)	0.0249 (2)	0.01555 (18)	0.00575 (12)	0.00256 (13)	−0.00114 (11)
Br2	0.02141 (19)	0.01770 (19)	0.0258 (2)	0.00415 (11)	0.00120 (14)	−0.00336 (12)
C3	0.058 (3)	0.028 (2)	0.038 (2)	−0.0083 (19)	0.016 (2)	−0.0224 (18)
C4	0.035 (2)	0.040 (2)	0.0247 (17)	0.0049 (17)	0.0140 (15)	−0.0078 (16)
C5	0.0224 (15)	0.0185 (15)	0.0237 (15)	−0.0002 (12)	0.0068 (13)	0.0004 (12)
C6	0.0191 (14)	0.0196 (15)	0.0197 (14)	0.0012 (12)	0.0031 (12)	−0.0065 (12)
C7	0.0206 (15)	0.0261 (17)	0.0221 (15)	0.0001 (13)	0.0073 (13)	−0.0011 (13)
C8	0.035 (2)	0.0235 (18)	0.042 (2)	−0.0112 (16)	0.0081 (17)	−0.0039 (16)
C9	0.084 (4)	0.056 (3)	0.045 (3)	−0.008 (3)	0.031 (3)	−0.031 (3)
O1	0.055 (2)	0.0260 (15)	0.069 (2)	−0.0105 (15)	0.0196 (19)	−0.0064 (16)
O2	0.114 (4)	0.052 (2)	0.044 (2)	−0.013 (2)	0.047 (2)	−0.0139 (17)
C1	0.022 (2)	0.0174 (19)	0.020 (2)	−0.0008 (15)	0.0109 (15)	−0.0023 (14)
C2	0.022 (2)	0.0174 (19)	0.020 (2)	−0.0008 (15)	0.0109 (15)	−0.0023 (14)
C1A	0.022 (2)	0.0174 (19)	0.020 (2)	−0.0008 (15)	0.0109 (15)	−0.0023 (14)
C2A	0.022 (2)	0.0174 (19)	0.020 (2)	−0.0008 (15)	0.0109 (15)	−0.0023 (14)
C1B	0.022 (2)	0.0174 (19)	0.020 (2)	−0.0008 (15)	0.0109 (15)	−0.0023 (14)
C2B	0.022 (2)	0.0174 (19)	0.020 (2)	−0.0008 (15)	0.0109 (15)	−0.0023 (14)

Geometric parameters (Å, º) top

Br1—C1	1.946 (7)	C5—C6	1.382 (5)
Br1—C2B	2.019 (13)	C6—C7	1.383 (5)
Br1—C2A	2.026 (15)	C7—C8	1.389 (5)
Br2—C1A	1.931 (14)	C9—O2	1.222 (7)
Br2—C1B	1.984 (13)	C9—O1	1.261 (7)
Br2—C2	2.015 (7)	C9—C1	1.569 (8)
C3—C4	1.383 (6)	C9—C1A	1.658 (14)
C3—C8	1.394 (7)	C9—C2B	1.695 (14)
C3—C2	1.553 (7)	C1—C2	1.504 (9)
C3—C2A	1.589 (14)	C1A—C2A	1.51 (2)
C3—C1B	1.616 (14)	C1B—C2B	1.469 (18)
C4—C5	1.368 (5)

C4—C3—C8	119.8 (3)	C2—C1—C9	108.0 (5)
C4—C3—C2	112.2 (4)	C2—C1—Br1	106.7 (5)
C8—C3—C2	127.4 (4)	C9—C1—Br1	110.0 (4)
C4—C3—C2A	114.9 (6)	C1—C2—C3	110.7 (5)
C8—C3—C2A	121.1 (6)	C1—C2—Br2	105.8 (4)
C4—C3—C1B	139.9 (6)	C3—C2—Br2	112.0 (4)
C8—C3—C1B	98.3 (6)	C2A—C1A—C9	101.7 (10)
C5—C4—C3	120.1 (4)	C2A—C1A—Br2	106.9 (9)
C4—C5—C6	120.5 (3)	C9—C1A—Br2	118.1 (7)
C5—C6—C7	120.2 (3)	C1A—C2A—C3	105.5 (10)
C6—C7—C8	119.4 (3)	C1A—C2A—Br1	105.7 (9)
C7—C8—C3	119.9 (4)	C3—C2A—Br1	119.1 (8)
O2—C9—O1	126.8 (4)	C2B—C1B—C3	102.3 (10)
O2—C9—C1	111.5 (5)	C2B—C1B—Br2	105.7 (9)
O1—C9—C1	121.2 (5)	C3—C1B—Br2	110.7 (7)
O2—C9—C1A	110.4 (6)	C1B—C2B—C9	101.5 (9)
O1—C9—C1A	117.6 (7)	C1B—C2B—Br1	105.4 (9)
O2—C9—C2B	146.2 (6)	C9—C2B—Br1	101.7 (7)
O1—C9—C2B	86.5 (6)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2O···O1ⁱ	0.84	1.81	2.638 (5)	167
C1—H1···Br2ⁱⁱ	1.00	2.96	3.845 (6)	148
C2—H2···Br1ⁱⁱⁱ	1.00	3.01	3.884 (7)	147

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

Acknowledgements

The authors would like to thank the Chemistry and Biochemistry Department of the Fredonia State University of New York for funding this study and for the purchase of the diffractometer.

References

Bourhis, L. J., Dolomanov, O. V., Gildea, R. J., Howard, J. A. K. & Puschmann, H. (2015). Acta Cryst. A71, 59–75. Web of Science CrossRef IUCr Journals Google Scholar
Bruker (2015). APEX2, SAINT, and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Dolomanov, O. V., Bourhis, L. J., Gildea, R. J., Howard, J. A. K. & Puschmann, H. (2009). J. Appl. Cryst. 42, 339–341. Web of Science CrossRef CAS IUCr Journals Google Scholar
Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466–470. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
Sheldrick, G. M. (2015). Acta Cryst. C71, 3–8. Web of Science CrossRef IUCr Journals Google Scholar
Thong, P. Y., Lo, K. M. & Ng, S. W. (2008). Acta Cryst. E64, o1946. CrossRef IUCr Journals Google Scholar

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