organic compounds
2,3-Dibromo-3-phenylpropionic acid
aDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
*Correspondence e-mail: seikweng@um.edu.my
In the crystal of the title compound, C9H8Br2O2, inversion dimers linked by two O—H⋯O hydrogen bonds occur. All of the carbon and oxygen atoms are disordered over two sets of sites in a 2:1 ratio.
Related literature
For threo-1,2-diphenyl-2,3-difluoropropionate, see: O'Hagan et al. (2006). For R-methyl 3-bromo-2-chloro-3-phenylpropionate, see: Shaw et al. (1995).
Experimental
Crystal data
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Refinement
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Data collection: APEX2 (Bruker, 2007); cell SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2008).
Supporting information
10.1107/S160053680802919X/tk2304sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S160053680802919X/tk2304Isup2.hkl
The compound was obtained as a side-product from the reaction of cyclopentyldiphenyltin cinnamate (0.3 g, 0.6 mmol) and 4-dimethylaminopyridine hydrobromide perbromide (0.25 g) in a mixture of chloroform and ethanol.
The structure is disordered over two positions with respect of the non-bromide atoms. The Br1 atom is connected to the carbon atom in the 2-position in the major component but is connected to the carbon atom in the 3-position in the minor component. Conversely, the Br2 atom is connected to the carbon atom in the 3-position in the major component but is connected to the carbon atom in the 2-position in the minor component. All distances in the major component were restrained to within 0.01 Å of their equivalents in the minor component. The phenyl rings were restrained into rigid hexagons of 1.39 Å sides. Additionally, the four-atom carboxyl and seven-atom benzyl units were each restrained to be nearly flat. The anisotropic displacement parameters of the primed atoms were restrained to be equal to those of the unprimed atoms; these were also restrained to be nearly isotropic. In the inital stages of the
the occupancy refined to an approximate 2:1 ratio. However, with the inclusion of hydrogen atoms, the was unstable. Ratios that were either slightly smaller or slightly larger than 2:1 did not yield any significant differences in the final residual index. The ratio was then fixed to 2:1 Oxygen and carbon-bound H-atoms were placed in calculated positions (C—H 0.95 to 1.00 Å, O–H 0.84 Å) and were included in the in the riding model approximation, with U(H) set to 1.2 to 1.5Ueq(C,O).Data collection: APEX2 (Bruker, 2007); cell
SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2008).Fig. 1. 70% Probability thermal ellipsoid plot (Barbour, 2001) of C9H8Br2O2. Hydrogen atoms are drawn as spheres of arbitrary radii. For clarity, the minor component is not shown. |
C9H8Br2O2 | F(000) = 1184 |
Mr = 307.97 | Dx = 2.046 Mg m−3 |
Orthorhombic, Pbca | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ac 2ab | Cell parameters from 8127 reflections |
a = 7.0278 (1) Å | θ = 2.2–28.2° |
b = 9.7105 (1) Å | µ = 8.07 mm−1 |
c = 29.2970 (4) Å | T = 100 K |
V = 1999.33 (4) Å3 | Block, colorless |
Z = 8 | 0.28 × 0.22 × 0.14 mm |
Bruker SMART APEX diffractometer | 2303 independent reflections |
Radiation source: fine-focus sealed tube | 2056 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.027 |
ω scans | θmax = 27.5°, θmin = 2.8° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −9→9 |
Tmin = 0.211, Tmax = 0.398 | k = −12→12 |
17420 measured reflections | l = −37→38 |
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)] = 0.025 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.066 | H-atom parameters constrained |
S = 1.06 | w = 1/[σ2(Fo2) + (0.0337P)2 + 3.2334P] where P = (Fo2 + 2Fc2)/3 |
2303 reflections | (Δ/σ)max = 0.001 |
127 parameters | Δρmax = 0.61 e Å−3 |
83 restraints | Δρmin = −0.62 e Å−3 |
C9H8Br2O2 | V = 1999.33 (4) Å3 |
Mr = 307.97 | Z = 8 |
Orthorhombic, Pbca | Mo Kα radiation |
a = 7.0278 (1) Å | µ = 8.07 mm−1 |
b = 9.7105 (1) Å | T = 100 K |
c = 29.2970 (4) Å | 0.28 × 0.22 × 0.14 mm |
Bruker SMART APEX diffractometer | 2303 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 2056 reflections with I > 2σ(I) |
Tmin = 0.211, Tmax = 0.398 | Rint = 0.027 |
17420 measured reflections |
R[F2 > 2σ(F2)] = 0.025 | 83 restraints |
wR(F2) = 0.066 | H-atom parameters constrained |
S = 1.06 | Δρmax = 0.61 e Å−3 |
2303 reflections | Δρmin = −0.62 e Å−3 |
127 parameters |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
Br1 | 0.48392 (4) | 0.31033 (3) | 0.364350 (9) | 0.02208 (9) | |
Br2 | −0.06355 (4) | 0.45596 (3) | 0.436758 (9) | 0.03094 (10) | |
O1 | 0.4216 (6) | 0.3279 (4) | 0.48256 (13) | 0.0308 (10) | 0.67 |
H1O | 0.4765 | 0.3569 | 0.5061 | 0.046* | 0.67 |
O2 | 0.4214 (10) | 0.5338 (5) | 0.4476 (3) | 0.0209 (10) | 0.67 |
C1 | 0.3847 (4) | 0.4118 (4) | 0.44922 (12) | 0.0189 (8) | 0.67 |
C2 | 0.2859 (5) | 0.3388 (4) | 0.40959 (12) | 0.0176 (7) | 0.67 |
H2 | 0.2344 | 0.2480 | 0.4200 | 0.021* | 0.67 |
C3 | 0.1313 (5) | 0.4223 (4) | 0.38839 (12) | 0.0183 (7) | 0.67 |
H3 | 0.1859 | 0.5130 | 0.3790 | 0.022* | 0.67 |
C4 | 0.0358 (4) | 0.3575 (5) | 0.34721 (14) | 0.0133 (8) | 0.67 |
C5 | −0.0307 (8) | 0.2228 (5) | 0.3486 (3) | 0.0186 (11) | 0.67 |
H5 | −0.0167 | 0.1697 | 0.3756 | 0.022* | 0.67 |
C6 | −0.1176 (9) | 0.1657 (9) | 0.3104 (4) | 0.0224 (6) | 0.67 |
H6 | −0.1631 | 0.0736 | 0.3114 | 0.027* | 0.67 |
C7 | −0.1381 (9) | 0.2433 (15) | 0.2709 (3) | 0.0181 (8) | 0.67 |
H7 | −0.1976 | 0.2043 | 0.2448 | 0.022* | 0.67 |
C8 | −0.0716 (13) | 0.3781 (14) | 0.26947 (16) | 0.0206 (7) | 0.67 |
H8 | −0.0856 | 0.4311 | 0.2424 | 0.025* | 0.67 |
C9 | 0.0154 (11) | 0.4352 (8) | 0.3076 (2) | 0.0183 (9) | 0.67 |
H9 | 0.0608 | 0.5273 | 0.3067 | 0.022* | 0.67 |
O1' | 0.3463 (14) | 0.3474 (10) | 0.4912 (3) | 0.0308 (10) | 0.33 |
H1'O | 0.4202 | 0.3715 | 0.5122 | 0.046* | 0.33 |
O2' | 0.380 (2) | 0.5445 (11) | 0.4542 (7) | 0.0209 (10) | 0.33 |
C1' | 0.3118 (9) | 0.4305 (9) | 0.4576 (2) | 0.0189 (8) | 0.33 |
C2' | 0.1737 (9) | 0.3684 (7) | 0.4228 (2) | 0.0176 (7) | 0.33 |
H2' | 0.1633 | 0.2666 | 0.4274 | 0.021* | 0.33 |
C3' | 0.2239 (9) | 0.3993 (8) | 0.3748 (2) | 0.0183 (7) | 0.33 |
H3' | 0.2355 | 0.5012 | 0.3709 | 0.022* | 0.33 |
C4' | 0.0862 (9) | 0.3432 (12) | 0.3394 (3) | 0.0133 (8) | 0.33 |
C5' | 0.0090 (19) | 0.2117 (12) | 0.3425 (6) | 0.0186 (11) | 0.33 |
H5' | 0.0421 | 0.1536 | 0.3674 | 0.022* | 0.33 |
C6' | −0.1164 (19) | 0.165 (2) | 0.3092 (8) | 0.0224 (6) | 0.33 |
H6' | −0.1692 | 0.0754 | 0.3113 | 0.027* | 0.33 |
C7' | −0.1648 (18) | 0.250 (3) | 0.2729 (6) | 0.0181 (8) | 0.33 |
H7' | −0.2505 | 0.2185 | 0.2501 | 0.022* | 0.33 |
C8' | −0.088 (3) | 0.382 (3) | 0.2698 (4) | 0.0206 (7) | 0.33 |
H8' | −0.1207 | 0.4398 | 0.2449 | 0.025* | 0.33 |
C9' | 0.038 (2) | 0.4282 (17) | 0.3031 (5) | 0.0183 (9) | 0.33 |
H9' | 0.0906 | 0.5181 | 0.3010 | 0.022* | 0.33 |
U11 | U22 | U33 | U12 | U13 | U23 | |
Br1 | 0.02081 (14) | 0.02271 (15) | 0.02272 (15) | −0.00251 (10) | −0.00187 (10) | −0.00479 (10) |
Br2 | 0.03118 (17) | 0.04015 (19) | 0.02150 (15) | 0.00134 (13) | 0.00331 (11) | −0.00921 (12) |
O1 | 0.055 (3) | 0.0188 (16) | 0.0182 (18) | −0.0063 (19) | −0.0143 (18) | 0.0006 (13) |
O2 | 0.034 (3) | 0.0169 (12) | 0.012 (3) | 0.0006 (16) | −0.0033 (18) | −0.0032 (12) |
C1 | 0.023 (2) | 0.0199 (18) | 0.0139 (17) | −0.0030 (19) | −0.0010 (16) | −0.0003 (14) |
C2 | 0.0211 (17) | 0.0149 (15) | 0.0166 (16) | −0.0017 (14) | 0.0007 (13) | −0.0010 (12) |
C3 | 0.021 (2) | 0.0159 (16) | 0.0175 (17) | −0.0033 (15) | 0.0002 (14) | −0.0028 (13) |
C4 | 0.007 (2) | 0.0153 (17) | 0.017 (2) | 0.0062 (19) | 0.0015 (16) | −0.0077 (14) |
C5 | 0.016 (3) | 0.0174 (16) | 0.023 (3) | 0.0023 (17) | −0.002 (2) | −0.0009 (15) |
C6 | 0.0180 (12) | 0.0183 (13) | 0.0310 (15) | −0.0018 (10) | −0.0052 (11) | −0.0067 (11) |
C7 | 0.009 (2) | 0.0239 (19) | 0.0215 (14) | 0.006 (2) | −0.0035 (16) | −0.0106 (11) |
C8 | 0.0169 (19) | 0.0259 (15) | 0.0190 (12) | 0.0082 (15) | 0.0007 (11) | −0.0025 (10) |
C9 | 0.017 (2) | 0.0167 (14) | 0.0211 (18) | 0.0027 (13) | 0.0015 (14) | −0.0037 (14) |
O1' | 0.055 (3) | 0.0188 (16) | 0.0182 (18) | −0.0063 (19) | −0.0143 (18) | 0.0006 (13) |
O2' | 0.034 (3) | 0.0169 (12) | 0.012 (3) | 0.0006 (16) | −0.0033 (18) | −0.0032 (12) |
C1' | 0.023 (2) | 0.0199 (18) | 0.0139 (17) | −0.0030 (19) | −0.0010 (16) | −0.0003 (14) |
C2' | 0.0211 (17) | 0.0149 (15) | 0.0166 (16) | −0.0017 (14) | 0.0007 (13) | −0.0010 (12) |
C3' | 0.021 (2) | 0.0159 (16) | 0.0175 (17) | −0.0033 (15) | 0.0002 (14) | −0.0028 (13) |
C4' | 0.007 (2) | 0.0153 (17) | 0.017 (2) | 0.0062 (19) | 0.0015 (16) | −0.0077 (14) |
C5' | 0.016 (3) | 0.0174 (16) | 0.023 (3) | 0.0023 (17) | −0.002 (2) | −0.0009 (15) |
C6' | 0.0180 (12) | 0.0183 (13) | 0.0310 (15) | −0.0018 (10) | −0.0052 (11) | −0.0067 (11) |
C7' | 0.009 (2) | 0.0239 (19) | 0.0215 (14) | 0.006 (2) | −0.0035 (16) | −0.0106 (11) |
C8' | 0.0169 (19) | 0.0259 (15) | 0.0190 (12) | 0.0082 (15) | 0.0007 (11) | −0.0025 (10) |
C9' | 0.017 (2) | 0.0167 (14) | 0.0211 (18) | 0.0027 (13) | 0.0015 (14) | −0.0037 (14) |
Br1—C2 | 1.942 (4) | C8—H8 | 0.9500 |
Br1—C3' | 2.044 (6) | C9—H9 | 0.9500 |
Br2—C2' | 1.916 (6) | O1'—C1' | 1.295 (8) |
Br2—C3 | 1.997 (3) | O1'—H1'O | 0.8400 |
O1—C1 | 1.298 (4) | O2'—C1' | 1.212 (8) |
O1—H1O | 0.8400 | C1'—C2' | 1.533 (8) |
O2—C1 | 1.213 (5) | C2'—C3' | 1.480 (7) |
C1—C2 | 1.527 (5) | C2'—H2' | 1.0000 |
C2—C3 | 1.491 (5) | C3'—C4' | 1.518 (7) |
C2—H2 | 1.0000 | C3'—H3' | 1.0000 |
C3—C4 | 1.517 (4) | C4'—C5' | 1.3900 |
C3—H3 | 1.0000 | C4'—C9' | 1.3900 |
C4—C5 | 1.3900 | C5'—C6' | 1.3900 |
C4—C9 | 1.3900 | C5'—H5' | 0.9500 |
C5—C6 | 1.3900 | C6'—C7' | 1.3900 |
C5—H5 | 0.9500 | C6'—H6' | 0.9500 |
C6—C7 | 1.3900 | C7'—C8' | 1.3900 |
C6—H6 | 0.9500 | C7'—H7' | 0.9500 |
C7—C8 | 1.3900 | C8'—C9' | 1.3900 |
C7—H7 | 0.9500 | C8'—H8' | 0.9500 |
C8—C9 | 1.3900 | C9'—H9' | 0.9500 |
C1—O1—H1O | 120.0 | C1'—O1'—H1'O | 120.0 |
O2—C1—O1 | 126.8 (6) | O2'—C1'—O1' | 124.0 (13) |
O2—C1—C2 | 121.4 (6) | O2'—C1'—C2' | 123.8 (13) |
O1—C1—C2 | 111.8 (4) | O1'—C1'—C2' | 112.3 (8) |
C3—C2—C1 | 113.3 (3) | C3'—C2'—C1' | 113.7 (6) |
C3—C2—Br1 | 108.4 (2) | C3'—C2'—Br2 | 108.7 (4) |
C1—C2—Br1 | 105.0 (2) | C1'—C2'—Br2 | 103.5 (4) |
C3—C2—H2 | 110.0 | C3'—C2'—H2' | 110.2 |
C1—C2—H2 | 110.0 | C1'—C2'—H2' | 110.2 |
Br1—C2—H2 | 110.0 | Br2—C2'—H2' | 110.2 |
C2—C3—C4 | 115.4 (3) | C2'—C3'—C4' | 115.0 (6) |
C2—C3—Br2 | 107.0 (2) | C2'—C3'—Br1 | 105.6 (4) |
C4—C3—Br2 | 109.20 (19) | C4'—C3'—Br1 | 108.5 (4) |
C2—C3—H3 | 108.3 | C2'—C3'—H3' | 109.2 |
C4—C3—H3 | 108.3 | C4'—C3'—H3' | 109.2 |
Br2—C3—H3 | 108.3 | Br1—C3'—H3' | 109.2 |
C5—C4—C9 | 120.0 | C5'—C4'—C9' | 120.0 |
C5—C4—C3 | 121.0 (5) | C5'—C4'—C3' | 122.3 (11) |
C9—C4—C3 | 119.0 (5) | C9'—C4'—C3' | 117.7 (11) |
C4—C5—C6 | 120.0 | C4'—C5'—C6' | 120.0 |
C4—C5—H5 | 120.0 | C4'—C5'—H5' | 120.0 |
C6—C5—H5 | 120.0 | C6'—C5'—H5' | 120.0 |
C7—C6—C5 | 120.0 | C7'—C6'—C5' | 120.0 |
C7—C6—H6 | 120.0 | C7'—C6'—H6' | 120.0 |
C5—C6—H6 | 120.0 | C5'—C6'—H6' | 120.0 |
C6—C7—C8 | 120.0 | C6'—C7'—C8' | 120.0 |
C6—C7—H7 | 120.0 | C6'—C7'—H7' | 120.0 |
C8—C7—H7 | 120.0 | C8'—C7'—H7' | 120.0 |
C7—C8—C9 | 120.0 | C7'—C8'—C9' | 120.0 |
C7—C8—H8 | 120.0 | C7'—C8'—H8' | 120.0 |
C9—C8—H8 | 120.0 | C9'—C8'—H8' | 120.0 |
C8—C9—C4 | 120.0 | C8'—C9'—C4' | 120.0 |
C8—C9—H9 | 120.0 | C8'—C9'—H9' | 120.0 |
C4—C9—H9 | 120.0 | C4'—C9'—H9' | 120.0 |
O2—C1—C2—C3 | −40.3 (4) | O2'—C1'—C2'—Br2 | −77.8 (5) |
O1—C1—C2—C3 | 140.0 (3) | O1'—C1'—C2'—Br2 | 102.1 (5) |
O2—C1—C2—Br1 | 77.8 (3) | C3—Br2—C2'—C3' | 0.9 (4) |
O1—C1—C2—Br1 | −101.9 (2) | C3—Br2—C2'—C1' | 122.1 (7) |
C1—C2—C3—C4 | 176.8 (3) | C1'—C2'—C3'—C4' | −178.0 (6) |
Br1—C2—C3—C4 | 60.7 (4) | Br2—C2'—C3'—C4' | −63.3 (7) |
C1—C2—C3—Br2 | −61.5 (3) | C1'—C2'—C3'—Br1 | 62.4 (6) |
Br1—C2—C3—Br2 | −177.59 (16) | Br2—C2'—C3'—Br1 | 177.1 (3) |
C2—C3—C4—C5 | 49.8 (4) | C2—Br1—C3'—C2' | 0.1 (3) |
Br2—C3—C4—C5 | −70.8 (3) | C2—Br1—C3'—C4' | −123.7 (8) |
C2—C3—C4—C9 | −130.2 (4) | C2'—C3'—C4'—C5' | −42.3 (8) |
Br2—C3—C4—C9 | 109.2 (3) | Br1—C3'—C4'—C5' | 75.6 (6) |
C9—C4—C5—C6 | 0.0 | C2'—C3'—C4'—C9' | 137.7 (8) |
C3—C4—C5—C6 | −179.99 (8) | Br1—C3'—C4'—C9' | −104.3 (6) |
C4—C5—C6—C7 | 0.0 | C9'—C4'—C5'—C6' | 0.0 |
C5—C6—C7—C8 | 0.0 | C3'—C4'—C5'—C6' | −179.96 (9) |
C6—C7—C8—C9 | 0.0 | C4'—C5'—C6'—C7' | 0.0 |
C7—C8—C9—C4 | 0.0 | C5'—C6'—C7'—C8' | 0.0 |
C5—C4—C9—C8 | 0.0 | C6'—C7'—C8'—C9' | 0.0 |
C3—C4—C9—C8 | 179.99 (8) | C7'—C8'—C9'—C4' | 0.0 |
O2'—C1'—C2'—C3' | 40.0 (6) | C5'—C4'—C9'—C8' | 0.0 |
O1'—C1'—C2'—C3' | −140.1 (6) | C3'—C4'—C9'—C8' | 179.96 (8) |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1o···O2i | 0.84 | 1.86 | 2.68 (1) | 165 |
O1′—H1′o···O2i | 0.84 | 1.86 | 2.69 (1) | 166 |
Symmetry code: (i) −x+1, −y+1, −z+1. |
Experimental details
Crystal data | |
Chemical formula | C9H8Br2O2 |
Mr | 307.97 |
Crystal system, space group | Orthorhombic, Pbca |
Temperature (K) | 100 |
a, b, c (Å) | 7.0278 (1), 9.7105 (1), 29.2970 (4) |
V (Å3) | 1999.33 (4) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 8.07 |
Crystal size (mm) | 0.28 × 0.22 × 0.14 |
Data collection | |
Diffractometer | Bruker SMART APEX diffractometer |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.211, 0.398 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 17420, 2303, 2056 |
Rint | 0.027 |
(sin θ/λ)max (Å−1) | 0.650 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.025, 0.066, 1.06 |
No. of reflections | 2303 |
No. of parameters | 127 |
No. of restraints | 83 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.61, −0.62 |
Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001), publCIF (Westrip, 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1o···O2i | 0.84 | 1.86 | 2.68 (1) | 165 |
O1'—H1'o···O2i | 0.84 | 1.86 | 2.69 (1) | 166 |
Symmetry code: (i) −x+1, −y+1, −z+1. |
Acknowledgements
We thank the University of Malaya for funding this study (FR155/2007 A) and also for the purchase of the diffractometer.
References
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The compound (Scheme I, Fig. 1) was obtained as a side-product from the reaction of cyclopentyldiphenyltin cinnamate and 4-dimethylaminopyridine hydrobromide perbromide. Possibly, bromine added across the double bond of the cinnamate group followed by cleavage of the tin–carbon bond. Only few dihalogenproponic acid derivatives have been characterized by X-ray crystallography. These are limited to, for example, threo-methyl 2,3-difluoropropionate (O'Hagan et al., 2006) and R-methyl 3-bromo-2-chloro-3-phenylpropionate (Shaw et al., 1995).