organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890
Volume 71| Part 7| July 2015| Pages o523-o524

Crystal structure of 3-bromo-2-hy­dr­oxy­benzo­nitrile

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aDepartment of Chemistry, Vassar College, Poughkeepsie, NY 12604, USA, and bX-Ray Diffraction Facility, MIT Department of Chemistry, 77 Massachusetts Avenue, Building 2, Room 325, Cambridge, MA, 02139-4307, USA
*Correspondence e-mail: jotanski@vassar.edu

Edited by S. V. Lindeman, Marquette University, USA (Received 18 June 2015; accepted 22 June 2015; online 27 June 2015)

The crystal structure of the title compound, C7H4BrNO, has been determined, revealing a partial mol­ecular packing disorder such that a 180° rotation of the mol­ecule about the phenol C—O bond results in disorder of the bromine and nitrile groups. The disorder has been parameterized as a disorder of only the bromine and nitrile substituents on a unique phenol ring. An intra­molecular O—H⋯Br contact occurs. In the crystal, O—H⋯Br/O—H⋯Nnitrile hydrogen bonding is present between the disordered bromine and nitrile substituents and the phenol group, forming a spiral chain about a twofold screw axis extending parallel to the b-axis direction. Within this spiral chain, the mol­ecules also inter­act, forming offset face-to-face π-stacking inter­actions with plane-to-centroid distance of 3.487 (1) Å.

1. Related literature

For syntheses of the title compound, see: Anwar & Hansen (2008[Anwar, H. & Hansen, T. (2008). Tetrahedron Lett. 49, 4443-4445.]); Nakai et al. (2014[Nakai, Y., Moriyama, K. & Togo, H. (2014). Eur. J. Org. Chem. pp. 6077-6083.]); Whiting et al. (2015[Whiting, E., Lanning, M. E., Scheenstra, J. A. & Fletcher, S. (2015). J. Org. Chem. 80, 1229-1234.]). For its use as a synthetic reagent, see: Li & Chua (2011[Li, L. & Chua, W. K. S. (2011). Tetrahedron Lett. 52, 1574-1577.]); Mulzer & Coates (2011[Mulzer, M. & Coates, G. W. (2011). Org. Lett. 13, 1426-1428.]). For related crystal structures, see: Beswick et al. (1996[Beswick, C., Kubicki, M. & Codding, P. W. (1996). Acta Cryst. C52, 3171-3173.]); Oh & Tanski (2012[Oh, S. & Tanski, J. M. (2012). Acta Cryst. E68, o2617.]). For information on π-stacking, see: Hunter & Sanders (1990[Hunter, C. A. & Sanders, J. K. M. (1990). J. Am. Chem. Soc. 112, 5525-5534.]); Lueckheide et al. (2013[Lueckheide, M., Rothman, N., Ko, B. & Tanski, J. M. (2013). Polyhedron, 58, 79-84.]). For information on the refinement of disordered crystal structures, see: Müller (2009[Müller, P. (2009). Crystallogr. Rev. 15, 57-83.]); Thorn et al. (2012[Thorn, A., Dittrich, B. & Sheldrick, G. M. (2012). Acta Cryst. A68, 448-451.]).

[Scheme 1]

2. Experimental

2.1. Crystal data

  • C7H4BrNO

  • Mr = 198.02

  • Monoclinic, P 21 /c

  • a = 13.0171 (7) Å

  • b = 3.8488 (2) Å

  • c = 13.5989 (7) Å

  • β = 96.062 (1)°

  • V = 677.50 (6) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 5.98 mm−1

  • T = 125 K

  • 0.22 × 0.10 × 0.04 mm

2.2. Data collection

  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2013[Bruker (2013). SAINT, SADABS and APEX2. Bruxer AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.57, Tmax = 0.80

  • 9903 measured reflections

  • 1977 independent reflections

  • 1776 reflections with I > 2σ(I)

  • Rint = 0.025

2.3. Refinement

  • R[F2 > 2σ(F2)] = 0.020

  • wR(F2) = 0.049

  • S = 1.08

  • 1977 reflections

  • 110 parameters

  • 102 restraints

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

  • Δρmax = 0.37 e Å−3

  • Δρmin = −0.45 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1⋯N1i 0.81 (2) 2.04 (2) 2.810 (3) 159 (2)
O1—H1⋯Br1A 0.81 (2) 2.82 (2) 3.262 (5) 116 (2)
O1—H1⋯Br1Ai 0.81 (2) 2.62 (2) 3.379 (5) 156 (2)
Symmetry code: (i) [-x+1, y-{\script{1\over 2}}, -z+{\script{3\over 2}}].

Data collection: APEX2 (Bruker, 2013[Bruker (2013). SAINT, SADABS and APEX2. Bruxer AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2013[Bruker (2013). SAINT, SADABS and APEX2. Bruxer AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015[Sheldrick, G. M. (2015). Acta Cryst. C71, 3-8.]); molecular graphics: SHELXTL2014; software used to prepare material for publication: SHELXTL2014, OLEX2 (Dolomanov et al., 2009[Dolomanov, O. V., Bourhis, L. J., Gildea, R. J., Howard, J. A. K. & Puschmann, H. (2009). J. Appl. Cryst. 42, 339-341.]) and Mercury (Macrae et al., 2008[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.]).

Supporting information


Structural commentary top

The title compound, 3-bromo-2-hy­droxy­benzo­nitrile, may be prepared by the addition of a cyano group to o-bromo­phenol (Anwar & Hansen, 2008; Nakai et al. 2014). It has also recently been synthesized by the one-pot conversion of the salicylaldoxime, (E)-3-bromo-2-hy­droxy­benzaldehyde oxime, directly to 3-bromo-2-hy­droxy­benzo­nitrile (Whiting et al., 2015). 3-Bromo-2-hy­droxy­benzo­nitrile is used as a synthetic reagent in the synthesis of 3,4-fused isoquinolin-1(2H)-one analogs (Li & Chua, 2011) and ampakine heterocycles which are a promising as a therapy for neurodegenerative diseases (Mulzer & Coates, 2011). The crystal structure of an isomer of the title compound which differs only in the position of the bromine substituent, 5-bromo-2-hy­droxy­benzo­nitrile, has previously been published (Oh & Tanski, 2012).

3-Bromo-2-hy­droxy­benzo­nitrile, (Fig. 1), crystallizes with a partial molecular packing disorder, where the bromine and nitrile substituents ortho to the phenol group are disordered with one another via a 180° rotation of the molecule about the carbon-oxygen bond of the phenol moiety. The disorder has been modeled as a disorder of only the bromine and nitrile substituents on a unique phenol ring, where the phenolic hydroxyl itself is not disordered, and the model has been refined with the help of similarity and advanced rigid bond restraints (Thorn et al., 2012). Although the accuracy of the observed metrical parameters for the disordered groups is impacted by the refinement of the disorder, the bond lengths are nevertheless comparable to those found in related structures. The nitrile bond lengths C7—N1 and C7A—N1A of 1.161 (4) and 1.14 (2) Å, respectively, are similar to those seen in the related structures 5-bromo-2-hy­droxy­benzo­nitrile, with nitrile CN distance 1.142 (4) Å (Oh & Tanski, 2012), and the unbrominated analog, o-cyano­phenol, with CN distance 1.136 (2) Å (Beswick et al., 1996). The aromatic bromine bond lengths C1—Br1A and C3—Br1 of 1.988 (5) Å and 1.907 (2) Å, respectively, are also similar to those seen in the related structure 5-bromo-2-hy­droxy­benzo­nitrile, with C—Br length 1.897 (3) Å (Oh & Tanski, 2012).

The molecules of the title compound pack together in the solid state with inter­molecular O—H···Br/O—H···Nnitrile hydrogen bonding (Fig. 2, Table 2). The hydrogen bonding is disordered with respect to the disordered bromine and nitrile substituents, not with respect to the phenol hydroxyl, which is found to have only one orientation. This hydrogen bonding forms a one-dimensional spiral chain extending parallel to the crystallographic b-axis, about the two-fold screw axis in P21/c with direction [0,1,0] at 1/2, y, 1/4. Within the chains, the molecules also inter­act via an offset face-to-face π-stacking inter­action. This π-stacking is characterized by a centroid-to-centroid distance of 3.8488 (2) Å, a plane-to-centroid distance of 3.487 (1) Å, and a ring offset or ring-slippage distance of 1.630 (2) Å (Hunter & Saunders, 1990; Lueckheide et al., 2013).

Synthesis and crystallization top

3-Bromo-2-hy­droxy­benzo­nitrile (97%) was purchased from Aldrich Chemical Company, USA, and was recrystallized from acetone.

Refinement top

The structure was refined against F2 using all data with SHELXL2014 (Sheldrick, 2015), employing established refinement strategies (Müller, 2009). All non-hydrogen atoms were refined anisotropically. Hydrogen atoms on carbon were included in calculated positions and refined using a riding model at C–H = 0.95 Å and Uiso(H) = 1.2 × Ueq(C) of the aryl C-atoms. Coordinates for the hydrogen atom on oxygen were taken from the difference Fourier synthesis and the hydrogen atom was subsequently refined semi-freely with the help of an O—H distance restraint (target value 0.84 (2) Å) while constraining its Uiso to 1.5 times the Ueq of the oxygen atom. The extinction parameter refined to zero and was removed from the refinement. The structure exhibits a partial molecular disorder. The disorder was successfully modeled and refined with the help of similarity restraints on 1,2- and 1,3-distances and displacement parameters as well as advanced rigid-bond restraints (Thorn et al., 2012) for anisotropic displacement parameters, and inter­atomic distance restraints.

Related literature top

For syntheses of the title compound, see: Anwar & Hansen (2008); Nakai et al. (2014); Whiting et al. (2015). For its use as a synthetic reagent, see: Li & Chua (2011); Mulzer & Coates (2011). For related crystal structures, see: Beswick et al. (1996); Oh & Tanski (2012). For information on π-stacking, see: Hunter & Sanders (1990); Lueckheide et al. (2013). For information on the refinement of disordered crystal structures, see: Müller (2009); Thorn et al. (2012).

Computing details top

Data collection: APEX2 (Bruker, 2013); cell refinement: SAINT (Bruker, 2013); data reduction: SAINT (Bruker, 2013); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: SHELXTL2014 (Sheldrick, 2008); software used to prepare material for publication: SHELXTL2014 (Sheldrick, 2008), OLEX2 (Dolomanov et al., 2009) and Mercury (Macrae et al., 2008).

Figures top
[Figure 1] Fig. 1. : A view of the title compound showing the disordered nitrile and bromine substituents, with displacement ellipsoids shown at the 50% probability level.
[Figure 2] Fig. 2. : A view of the intermolecular OH···Br/OH···Nnitrile hydrogen bonding interactions (dashed lines) forming a helical one-dimensional chain, with displacement ellipsoids shown at the 50% probability level. See Table 1 for symmetry code (i). A thin solid line indicates an intramolecular O—H···Br hydrogen bond, and a thick solid line indicates a π-stacking centroid-to-centroid interaction.
3-Bromo-2-hydroxybenzonitrile top
Crystal data top
C7H4BrNOF(000) = 384
Mr = 198.02Dx = 1.941 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
a = 13.0171 (7) ÅCell parameters from 6401 reflections
b = 3.8488 (2) Åθ = 3.0–30.5°
c = 13.5989 (7) ŵ = 5.98 mm1
β = 96.062 (1)°T = 125 K
V = 677.50 (6) Å3Needle, colourless
Z = 40.22 × 0.10 × 0.04 mm
Data collection top
Bruker APEXII CCD
diffractometer
1977 independent reflections
Radiation source: fine-focus sealed tube1776 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.025
Detector resolution: 8.3333 pixels mm-1θmax = 30.0°, θmin = 3.0°
ϕ and ω scansh = 1818
Absorption correction: multi-scan
(SADABS; Bruker, 2013)
k = 55
Tmin = 0.57, Tmax = 0.80l = 1919
9903 measured reflections
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)] = 0.020Hydrogen site location: mixed
wR(F2) = 0.049H atoms treated by a mixture of independent and constrained refinement
S = 1.08 w = 1/[σ2(Fo2) + (0.0241P)2 + 0.2328P]
where P = (Fo2 + 2Fc2)/3
1977 reflections(Δ/σ)max = 0.002
110 parametersΔρmax = 0.37 e Å3
102 restraintsΔρmin = 0.45 e Å3
Crystal data top
C7H4BrNOV = 677.50 (6) Å3
Mr = 198.02Z = 4
Monoclinic, P21/cMo Kα radiation
a = 13.0171 (7) ŵ = 5.98 mm1
b = 3.8488 (2) ÅT = 125 K
c = 13.5989 (7) Å0.22 × 0.10 × 0.04 mm
β = 96.062 (1)°
Data collection top
Bruker APEXII CCD
diffractometer
1977 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2013)
1776 reflections with I > 2σ(I)
Tmin = 0.57, Tmax = 0.80Rint = 0.025
9903 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.020102 restraints
wR(F2) = 0.049H atoms treated by a mixture of independent and constrained refinement
S = 1.08Δρmax = 0.37 e Å3
1977 reflectionsΔρmin = 0.45 e Å3
110 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)
O10.70927 (9)0.4093 (4)0.76425 (9)0.0264 (3)
H10.6483 (13)0.420 (6)0.7450 (18)0.04*
C10.66122 (12)0.6091 (4)0.92251 (12)0.0195 (3)
C70.5648 (2)0.7338 (8)0.8786 (2)0.0225 (6)0.9272 (13)
N10.4862 (2)0.8421 (7)0.84343 (18)0.0281 (5)0.9272 (13)
Br1A0.5216 (4)0.7707 (10)0.8684 (3)0.0332 (13)0.0728 (13)
C20.73013 (11)0.4575 (4)0.86256 (11)0.0185 (3)
C30.82692 (11)0.3564 (4)0.90818 (11)0.0186 (3)
Br10.92397 (2)0.15982 (5)0.82834 (2)0.02008 (6)0.9272 (13)
C7A0.8979 (14)0.192 (6)0.8577 (15)0.02008 (6)0.0728 (13)
N1A0.9658 (13)0.131 (5)0.8138 (13)0.02008 (6)0.0728 (13)
C40.85334 (13)0.3982 (4)1.00854 (12)0.0234 (3)
H40.91940.32591.03760.028*
C50.78350 (14)0.5460 (5)1.06728 (12)0.0267 (3)
H50.80170.57391.13630.032*
C60.68739 (13)0.6519 (4)1.02446 (12)0.0237 (3)
H60.63940.75321.0640.028*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0175 (5)0.0414 (7)0.0194 (5)0.0021 (5)0.0026 (4)0.0046 (5)
C10.0174 (7)0.0191 (7)0.0216 (7)0.0012 (5)0.0008 (6)0.0021 (6)
C70.0186 (12)0.0255 (11)0.0237 (10)0.0015 (11)0.0044 (11)0.0002 (7)
N10.0217 (12)0.0369 (13)0.0253 (11)0.0038 (9)0.0012 (8)0.0005 (9)
Br1A0.029 (3)0.031 (2)0.040 (2)0.001 (2)0.003 (2)0.0004 (15)
C20.0173 (7)0.0186 (7)0.0190 (7)0.0024 (6)0.0007 (5)0.0016 (6)
C30.0161 (6)0.0173 (7)0.0224 (7)0.0009 (6)0.0012 (5)0.0015 (6)
Br10.01502 (9)0.02106 (9)0.02437 (10)0.00176 (7)0.00305 (6)0.00176 (7)
C7A0.01502 (9)0.02106 (9)0.02437 (10)0.00176 (7)0.00305 (6)0.00176 (7)
N1A0.01502 (9)0.02106 (9)0.02437 (10)0.00176 (7)0.00305 (6)0.00176 (7)
C40.0198 (7)0.0252 (8)0.0241 (8)0.0006 (6)0.0037 (6)0.0047 (6)
C50.0290 (8)0.0325 (9)0.0176 (7)0.0004 (7)0.0023 (6)0.0027 (7)
C60.0236 (8)0.0265 (8)0.0215 (7)0.0004 (6)0.0043 (6)0.0003 (7)
Geometric parameters (Å, º) top
O1—C21.3487 (19)C3—C41.381 (2)
O1—H10.810 (16)C3—Br11.9071 (16)
C1—C21.401 (2)C7A—N1A1.143 (16)
C1—C61.402 (2)C4—C51.393 (2)
C1—C71.416 (3)C4—H40.95
C1—Br1A1.988 (5)C5—C61.384 (2)
C7—N11.161 (4)C5—H50.95
C2—C31.400 (2)C6—H60.95
C3—C7A1.363 (14)
C2—O1—H1113.7 (18)C4—C3—Br1119.86 (12)
C2—C1—C6121.38 (14)C2—C3—Br1118.52 (11)
C2—C1—C7119.29 (17)N1A—C7A—C3164 (3)
C6—C1—C7119.28 (17)C3—C4—C5120.30 (15)
C2—C1—Br1A122.09 (17)C3—C4—H4119.9
C6—C1—Br1A116.52 (16)C5—C4—H4119.9
N1—C7—C1178.7 (4)C6—C5—C4119.63 (15)
O1—C2—C3118.60 (14)C6—C5—H5120.2
O1—C2—C1124.04 (14)C4—C5—H5120.2
C3—C2—C1117.35 (14)C5—C6—C1119.71 (16)
C7A—C3—C4116.1 (9)C5—C6—H6120.1
C7A—C3—C2122.2 (9)C1—C6—H6120.1
C4—C3—C2121.62 (15)
C6—C1—C2—O1179.94 (15)C1—C2—C3—Br1178.46 (11)
C7—C1—C2—O12.6 (3)C4—C3—C7A—N1A88 (8)
Br1A—C1—C2—O10.4 (3)C2—C3—C7A—N1A96 (8)
C6—C1—C2—C31.2 (2)C7A—C3—C4—C5176.5 (12)
C7—C1—C2—C3176.33 (18)C2—C3—C4—C50.4 (2)
Br1A—C1—C2—C3179.33 (18)Br1—C3—C4—C5179.11 (13)
O1—C2—C3—C7A4.1 (13)C3—C4—C5—C60.2 (3)
C1—C2—C3—C7A176.9 (13)C4—C5—C6—C10.1 (3)
O1—C2—C3—C4179.97 (15)C2—C1—C6—C50.6 (2)
C1—C2—C3—C41.1 (2)C7—C1—C6—C5176.89 (19)
O1—C2—C3—Br10.5 (2)Br1A—C1—C6—C5179.86 (18)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···N1i0.81 (2)2.04 (2)2.810 (3)159 (2)
O1—H1···Br1A0.81 (2)2.82 (2)3.262 (5)116 (2)
O1—H1···Br1Ai0.81 (2)2.62 (2)3.379 (5)156 (2)
Symmetry code: (i) x+1, y1/2, z+3/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···N1i0.810 (16)2.038 (18)2.810 (3)159.(2)
O1—H1···Br1A0.810 (16)2.82 (2)3.262 (5)116.(2)
O1—H1···Br1Ai0.810 (16)2.621 (19)3.379 (5)156.(2)
Symmetry code: (i) x+1, y1/2, z+3/2.
 

Acknowledgements

This work was supported by Vassar College. X-ray facilities were provided for by the US·National Science Foundation (grant No. 0521237 to JMT).

References

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Volume 71| Part 7| July 2015| Pages o523-o524
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