organic compounds
5-Bromo-2-hydroxybenzonitrile
aDepartment of Chemistry, Vassar College, Poughkeepsie, NY 12604, USA
*Correspondence e-mail: jotanski@vassar.edu
The title compound, C7H4BrNO, crystallizes with two molecules in the The two molecules exhibit nearly linear C—C≡N nitrile bond angles of 179.1 (4) and 177.1 (4)°. In the crystal, the molecules are linked into a one-dimensional hydrogen-bonded chain by interactions between the phenol H atom and the nitrile N atom [N⋯O = 2.805 (4) and 2.810 (4) Å].
Related literature
For information on the synthesis of the title compound, see: Anwar & Hansen (2008); Bonnichon et al. (1999); Oberhauser (1997); Tamilselvan et al. (2009). For use as a synthetic reagent, see: Jiang et al. (2011); Tsuhako et al. (2012); Wetzel et al. (2011). For a related see: Beswick et al. (1996).
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: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.
Supporting information
10.1107/S1600536812031716/rk2372sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536812031716/rk2372Isup2.hkl
Supporting information file. DOI: 10.1107/S1600536812031716/rk2372Isup3.cml
Crystalline 5-bromo-2-hydroxybenzonitrile was purchased from Aldrich Chemical Company, USA, and was recrystallized from chloroform.
Hydrogen atoms based on carbon were included in calculated positions and refined using a riding model at C–H = 0.95Å and Uiso(H) = 1.2Ueq(Caryl). Hydrogen atoms based on oxygen were refined semifreely with the help of a distance restraint O–H = 0.84Å, and Uiso(H) = 1.5Ueq(O).
The title compound, 5-bromo-2-hydroxybenzonitrile, may be prepared by a variety of methods, including bromination of o-cyanophenol (Oberhauser, 1997), additon of nitrile to p-bromophenol (Anwar & Hansen, 2008), cobalt(II) catalyzed conversion of 5-bromo-2-hydroxyaldoxime to the nitrile (Tamilselvan et al., 2009), and photochemically from 5-chloro-2-hydroxybenzonitrile in the presence of bromide ions (Bonnichon et al., 1999). The 5-bromo-2-hydroxybenzonitrile is used as a synthetic reagent in the synthesis of biologically active compounds such as potential antiretroviral drugs (Jiang et al., 2011), cancer therapies (Tsuhako et al., 2012), and osteoporosis treatments (Wetzel et al., 2011).
The
contains two uniqe molecules of the title compound (Fig. 1) which are hydrogen bonded into an infinite one-dimensional chain (Fig. 2). The phenoxy group acts as the hydrogen donor and the nitrile group as the acceptor, with O···N distances of 2.805 (4)Å and 2.810 (4)Å, and O–H···N angles of 170 (5)° and 175 (5)°. The metrical parameters are similar to those found in the structure of o-cyanonitrile, which also crystallizes with two molecules in the and exhibts O···N distances of 2.795 (2)Å and 2.798 (2)Å, and O–H···N angles of 173 (2)° and 172 (2)° (Beswick et al., 1996). As in the structure of o-cyanonitrile, the molecules of the title compound are nearly planar, with a root mean square deviations from the plane of all atoms, excluding the aryl H atoms, of 0.0334Å and 0.2747Å. In each molecule in the the greatest deviation from the plane is the phenolic hydrogen atom, presumably to maximize the hydrogen bonding interaction between neighboring molecules, which make a dihedral angle between them of 12.6 (5)°.For information on the synthesis of the title compound, see: Anwar & Hansen (2008); Bonnichon et al. (1999); Oberhauser (1997); Tamilselvan et al. (2009). For use as a synthetic reagent, see: Jiang et al. (2011); Tsuhako et al. (2012); Wetzel et al. (2011). For a related
see: Beswick et al. (1996).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: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).C7H4BrNO | Z = 4 |
Mr = 198.01 | F(000) = 384 |
Triclinic, P1 | Dx = 1.888 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 3.8422 (3) Å | Cell parameters from 5206 reflections |
b = 8.5166 (7) Å | θ = 2.5–30.5° |
c = 21.6507 (18) Å | µ = 5.82 mm−1 |
α = 97.074 (1)° | T = 125 K |
β = 91.991 (1)° | Needle, colourless |
γ = 97.068 (1)° | 0.20 × 0.07 × 0.03 mm |
V = 696.83 (10) Å3 |
Bruker APEXII CCD diffractometer | 4213 independent reflections |
Radiation source: fine-focus sealed tube | 3254 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.032 |
φ and ω scans | θmax = 30.5°, θmin = 1.9° |
Absorption correction: multi-scan (SADABS; Bruker, 2007) | h = −5→5 |
Tmin = 0.389, Tmax = 0.845 | k = −12→12 |
11040 measured reflections | l = −30→30 |
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)] = 0.043 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.100 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | w = 1/[σ2(Fo2) + (0.050P)2 + 0.6935P] where P = (Fo2 + 2Fc2)/3 |
4213 reflections | (Δ/σ)max = 0.001 |
187 parameters | Δρmax = 1.67 e Å−3 |
2 restraints | Δρmin = −0.57 e Å−3 |
C7H4BrNO | γ = 97.068 (1)° |
Mr = 198.01 | V = 696.83 (10) Å3 |
Triclinic, P1 | Z = 4 |
a = 3.8422 (3) Å | Mo Kα radiation |
b = 8.5166 (7) Å | µ = 5.82 mm−1 |
c = 21.6507 (18) Å | T = 125 K |
α = 97.074 (1)° | 0.20 × 0.07 × 0.03 mm |
β = 91.991 (1)° |
Bruker APEXII CCD diffractometer | 4213 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2007) | 3254 reflections with I > 2σ(I) |
Tmin = 0.389, Tmax = 0.845 | Rint = 0.032 |
11040 measured reflections |
R[F2 > 2σ(F2)] = 0.043 | 2 restraints |
wR(F2) = 0.100 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | Δρmax = 1.67 e Å−3 |
4213 reflections | Δρmin = −0.57 e Å−3 |
187 parameters |
Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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. |
x | y | z | Uiso*/Ueq | ||
Br1 | 0.18318 (9) | 0.28671 (4) | 0.512507 (15) | 0.02561 (10) | |
Br2 | 0.29449 (9) | 0.79771 (4) | 0.004330 (16) | 0.02483 (10) | |
O1 | 0.5299 (7) | 0.0480 (3) | 0.25051 (11) | 0.0272 (5) | |
H1 | 0.477 (12) | 0.107 (5) | 0.2245 (17) | 0.041* | |
O2 | −0.0783 (7) | 0.5153 (3) | 0.23932 (11) | 0.0256 (5) | |
H2 | −0.155 (11) | 0.581 (4) | 0.2658 (16) | 0.038* | |
N1 | 0.6255 (9) | −0.2737 (4) | 0.32638 (14) | 0.0297 (7) | |
N2 | 0.2873 (9) | 0.2144 (4) | 0.15707 (14) | 0.0284 (7) | |
C1 | 0.5484 (9) | −0.1490 (4) | 0.33933 (15) | 0.0219 (6) | |
C2 | 0.4527 (8) | 0.0091 (4) | 0.35481 (15) | 0.0198 (6) | |
C3 | 0.4427 (9) | 0.1083 (4) | 0.30815 (15) | 0.0205 (6) | |
C4 | 0.3500 (9) | 0.2610 (4) | 0.32282 (16) | 0.0243 (7) | |
H4A | 0.3393 | 0.3289 | 0.2913 | 0.029* | |
C5 | 0.2735 (9) | 0.3141 (4) | 0.38330 (16) | 0.0224 (6) | |
H5A | 0.2114 | 0.4185 | 0.3933 | 0.027* | |
C6 | 0.2875 (8) | 0.2141 (4) | 0.42964 (15) | 0.0200 (6) | |
C7 | 0.3737 (8) | 0.0620 (4) | 0.41583 (14) | 0.0192 (6) | |
H7A | 0.3793 | −0.0061 | 0.4473 | 0.023* | |
C8 | 0.2157 (9) | 0.3355 (4) | 0.14778 (15) | 0.0213 (6) | |
C9 | 0.1384 (8) | 0.4920 (4) | 0.13853 (15) | 0.0188 (6) | |
C10 | −0.0049 (8) | 0.5841 (4) | 0.18745 (15) | 0.0196 (6) | |
C11 | −0.0606 (9) | 0.7398 (4) | 0.17991 (15) | 0.0211 (6) | |
H11A | −0.1568 | 0.8038 | 0.2124 | 0.025* | |
C12 | 0.0238 (9) | 0.8011 (4) | 0.12526 (16) | 0.0218 (6) | |
H12A | −0.0129 | 0.9073 | 0.1205 | 0.026* | |
C13 | 0.1624 (8) | 0.7076 (4) | 0.07722 (15) | 0.0190 (6) | |
C14 | 0.2219 (8) | 0.5542 (4) | 0.08324 (15) | 0.0196 (6) | |
H14A | 0.3182 | 0.4913 | 0.0504 | 0.023* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Br1 | 0.02688 (19) | 0.02853 (19) | 0.02188 (17) | 0.00764 (14) | 0.00549 (13) | −0.00014 (13) |
Br2 | 0.02437 (18) | 0.02336 (17) | 0.02838 (18) | 0.00123 (13) | 0.00333 (13) | 0.01102 (13) |
O1 | 0.0410 (15) | 0.0240 (13) | 0.0186 (11) | 0.0098 (11) | 0.0007 (10) | 0.0047 (9) |
O2 | 0.0380 (14) | 0.0226 (12) | 0.0173 (11) | 0.0072 (11) | 0.0050 (10) | 0.0026 (9) |
N1 | 0.0419 (19) | 0.0259 (16) | 0.0231 (15) | 0.0104 (13) | 0.0048 (13) | 0.0035 (12) |
N2 | 0.0417 (18) | 0.0210 (15) | 0.0223 (14) | 0.0063 (13) | −0.0009 (13) | 0.0004 (11) |
C1 | 0.0268 (17) | 0.0235 (17) | 0.0159 (14) | 0.0034 (13) | 0.0015 (12) | 0.0046 (12) |
C2 | 0.0197 (15) | 0.0184 (15) | 0.0215 (15) | 0.0034 (12) | 0.0004 (12) | 0.0024 (12) |
C3 | 0.0193 (15) | 0.0231 (16) | 0.0184 (15) | 0.0016 (12) | −0.0005 (12) | 0.0018 (12) |
C4 | 0.0289 (18) | 0.0220 (16) | 0.0230 (16) | 0.0050 (13) | −0.0003 (13) | 0.0058 (13) |
C5 | 0.0246 (16) | 0.0196 (15) | 0.0235 (16) | 0.0057 (12) | 0.0008 (13) | 0.0025 (12) |
C6 | 0.0177 (15) | 0.0242 (16) | 0.0182 (15) | 0.0036 (12) | 0.0014 (12) | 0.0023 (12) |
C7 | 0.0204 (15) | 0.0205 (15) | 0.0170 (14) | 0.0028 (12) | −0.0005 (12) | 0.0040 (12) |
C8 | 0.0268 (16) | 0.0213 (16) | 0.0154 (14) | 0.0021 (13) | 0.0010 (12) | 0.0017 (12) |
C9 | 0.0207 (15) | 0.0170 (14) | 0.0185 (14) | 0.0031 (12) | −0.0004 (12) | 0.0016 (11) |
C10 | 0.0199 (15) | 0.0179 (15) | 0.0198 (15) | 0.0002 (11) | −0.0021 (12) | 0.0009 (12) |
C11 | 0.0235 (16) | 0.0183 (15) | 0.0201 (15) | 0.0026 (12) | −0.0008 (12) | −0.0021 (12) |
C12 | 0.0218 (16) | 0.0170 (15) | 0.0260 (16) | 0.0023 (12) | −0.0043 (13) | 0.0025 (12) |
C13 | 0.0175 (14) | 0.0184 (15) | 0.0209 (15) | −0.0009 (11) | 0.0002 (12) | 0.0051 (12) |
C14 | 0.0167 (14) | 0.0196 (15) | 0.0214 (15) | 0.0005 (11) | 0.0003 (12) | 0.0004 (12) |
Br1—C6 | 1.897 (3) | C5—C6 | 1.397 (4) |
Br2—C13 | 1.896 (3) | C5—H5A | 0.9500 |
O1—C3 | 1.359 (4) | C6—C7 | 1.376 (4) |
O1—H1 | 0.834 (19) | C7—H7A | 0.9500 |
O2—C10 | 1.352 (4) | C8—C9 | 1.436 (4) |
O2—H2 | 0.836 (19) | C9—C14 | 1.399 (4) |
N1—C1 | 1.142 (4) | C9—C10 | 1.408 (4) |
N2—C8 | 1.139 (4) | C10—C11 | 1.396 (4) |
C1—C2 | 1.442 (4) | C11—C12 | 1.384 (5) |
C2—C3 | 1.397 (4) | C11—H11A | 0.9500 |
C2—C7 | 1.398 (4) | C12—C13 | 1.392 (5) |
C3—C4 | 1.393 (5) | C12—H12A | 0.9500 |
C4—C5 | 1.385 (5) | C13—C14 | 1.375 (4) |
C4—H4A | 0.9500 | C14—H14A | 0.9500 |
C3—O1—H1 | 110 (3) | C2—C7—H7A | 120.4 |
C10—O2—H2 | 110 (3) | N2—C8—C9 | 177.1 (4) |
N1—C1—C2 | 179.1 (4) | C14—C9—C10 | 120.9 (3) |
C3—C2—C7 | 120.8 (3) | C14—C9—C8 | 120.4 (3) |
C3—C2—C1 | 119.0 (3) | C10—C9—C8 | 118.6 (3) |
C7—C2—C1 | 120.2 (3) | O2—C10—C11 | 124.1 (3) |
O1—C3—C4 | 124.0 (3) | O2—C10—C9 | 117.3 (3) |
O1—C3—C2 | 116.7 (3) | C11—C10—C9 | 118.7 (3) |
C4—C3—C2 | 119.3 (3) | C12—C11—C10 | 120.2 (3) |
C5—C4—C3 | 120.1 (3) | C12—C11—H11A | 119.9 |
C5—C4—H4A | 119.9 | C10—C11—H11A | 119.9 |
C3—C4—H4A | 119.9 | C11—C12—C13 | 120.2 (3) |
C4—C5—C6 | 120.0 (3) | C11—C12—H12A | 119.9 |
C4—C5—H5A | 120.0 | C13—C12—H12A | 119.9 |
C6—C5—H5A | 120.0 | C14—C13—C12 | 121.0 (3) |
C7—C6—C5 | 120.7 (3) | C14—C13—Br2 | 119.6 (2) |
C7—C6—Br1 | 119.2 (2) | C12—C13—Br2 | 119.3 (2) |
C5—C6—Br1 | 120.1 (2) | C13—C14—C9 | 118.9 (3) |
C6—C7—C2 | 119.1 (3) | C13—C14—H14A | 120.5 |
C6—C7—H7A | 120.4 | C9—C14—H14A | 120.5 |
C7—C2—C3—O1 | 178.8 (3) | C14—C9—C10—O2 | −180.0 (3) |
C1—C2—C3—O1 | −0.8 (5) | C8—C9—C10—O2 | −3.4 (4) |
C7—C2—C3—C4 | −0.5 (5) | C14—C9—C10—C11 | −0.4 (5) |
C1—C2—C3—C4 | 179.9 (3) | C8—C9—C10—C11 | 176.2 (3) |
O1—C3—C4—C5 | −178.4 (3) | O2—C10—C11—C12 | 179.7 (3) |
C2—C3—C4—C5 | 0.9 (5) | C9—C10—C11—C12 | 0.1 (5) |
C3—C4—C5—C6 | −0.3 (5) | C10—C11—C12—C13 | 0.5 (5) |
C4—C5—C6—C7 | −0.6 (5) | C11—C12—C13—C14 | −0.8 (5) |
C4—C5—C6—Br1 | 179.9 (3) | C11—C12—C13—Br2 | −177.3 (2) |
C5—C6—C7—C2 | 1.0 (5) | C12—C13—C14—C9 | 0.5 (5) |
Br1—C6—C7—C2 | −179.6 (2) | Br2—C13—C14—C9 | 177.0 (2) |
C3—C2—C7—C6 | −0.4 (5) | C10—C9—C14—C13 | 0.1 (5) |
C1—C2—C7—C6 | 179.2 (3) | C8—C9—C14—C13 | −176.4 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···N2 | 0.83 (2) | 1.98 (2) | 2.805 (4) | 170 (5) |
O2—H2···N1i | 0.84 (2) | 1.98 (2) | 2.810 (4) | 175 (5) |
Symmetry code: (i) x−1, y+1, z. |
Experimental details
Crystal data | |
Chemical formula | C7H4BrNO |
Mr | 198.01 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 125 |
a, b, c (Å) | 3.8422 (3), 8.5166 (7), 21.6507 (18) |
α, β, γ (°) | 97.074 (1), 91.991 (1), 97.068 (1) |
V (Å3) | 696.83 (10) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 5.82 |
Crystal size (mm) | 0.20 × 0.07 × 0.03 |
Data collection | |
Diffractometer | Bruker APEXII CCD |
Absorption correction | Multi-scan (SADABS; Bruker, 2007) |
Tmin, Tmax | 0.389, 0.845 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 11040, 4213, 3254 |
Rint | 0.032 |
(sin θ/λ)max (Å−1) | 0.714 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.043, 0.100, 1.03 |
No. of reflections | 4213 |
No. of parameters | 187 |
No. of restraints | 2 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 1.67, −0.57 |
Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···N2 | 0.834 (19) | 1.98 (2) | 2.805 (4) | 170 (5) |
O2—H2···N1i | 0.836 (19) | 1.98 (2) | 2.810 (4) | 175 (5) |
Symmetry code: (i) x−1, y+1, z. |
Acknowledgements
This work was supported by Vassar College. X-ray facilities were provided by the US National Science Foundation (grant No. 0521237 to JMT).
References
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This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.
The title compound, 5-bromo-2-hydroxybenzonitrile, may be prepared by a variety of methods, including bromination of o-cyanophenol (Oberhauser, 1997), additon of nitrile to p-bromophenol (Anwar & Hansen, 2008), cobalt(II) catalyzed conversion of 5-bromo-2-hydroxyaldoxime to the nitrile (Tamilselvan et al., 2009), and photochemically from 5-chloro-2-hydroxybenzonitrile in the presence of bromide ions (Bonnichon et al., 1999). The 5-bromo-2-hydroxybenzonitrile is used as a synthetic reagent in the synthesis of biologically active compounds such as potential antiretroviral drugs (Jiang et al., 2011), cancer therapies (Tsuhako et al., 2012), and osteoporosis treatments (Wetzel et al., 2011).
The asymmetric unit contains two uniqe molecules of the title compound (Fig. 1) which are hydrogen bonded into an infinite one-dimensional chain (Fig. 2). The phenoxy group acts as the hydrogen donor and the nitrile group as the acceptor, with O···N distances of 2.805 (4)Å and 2.810 (4)Å, and O–H···N angles of 170 (5)° and 175 (5)°. The metrical parameters are similar to those found in the structure of o-cyanonitrile, which also crystallizes with two molecules in the asymmetric unit, and exhibts O···N distances of 2.795 (2)Å and 2.798 (2)Å, and O–H···N angles of 173 (2)° and 172 (2)° (Beswick et al., 1996). As in the structure of o-cyanonitrile, the molecules of the title compound are nearly planar, with a root mean square deviations from the plane of all atoms, excluding the aryl H atoms, of 0.0334Å and 0.2747Å. In each molecule in the asymmetric unit, the greatest deviation from the plane is the phenolic hydrogen atom, presumably to maximize the hydrogen bonding interaction between neighboring molecules, which make a dihedral angle between them of 12.6 (5)°.