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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 68| Part 4| April 2012| Page o1020
doi:10.1107/S1600536812009749

(6Z)-4-Bromo-6-{[(2-hy­dr­oxy­eth­yl)amino]­methyl­­idene}cyclo­hexa-2,4-dien-1-one

Shaaban K. Mohamed,a Mehmet Akkurt,b* Antar A. Abd Elhamid,a Kuldip Singhc and Herman Potgieterd

aChemistry and Environmental Science Division, School of Science, Manchester Metropolitan University, England, bDepartment of Physics, Faculty of Sciences, Erciyes University, 38039 Kayseri, Turkey, cDepartment of Chemistry, University of Leicester, Leicester, England, and dSchool of Research, Enterprise & Innovation, Manchester Metropolitan University, England
*Correspondence e-mail: akkurt@erciyes.edu.tr

(Received 2 March 2012; accepted 5 March 2012; online 10 March 2012)

The title mol­ecule, C9H10BrNO2, excluding methyl­ene H atoms and the C—OH group, is essentially planar, with a maximum deviation of 0.037 (2) Å for the N atom. The N—C—C—O torsion angle is −63.1 (3)°. The mol­ecular structure is stabilized by a weak intra­molecular N—H⋯O(carbonyl) hydrogen bond, forming an S(6) motif. In the crystal, mol­ecules are linked by O—H⋯O and C—H⋯O hydrogen bonds, forming a three-dimensional network.

Related literature

For background to amino­alcohol derivatives and their bioactivity, see: Thomas et al. (1990[Thomas, G. J. (1990). Recent Progress in the Chemical Synthesis of Antibiotics, edited by G. Lukacs & M. Ohno, p. 468. Berlin: Springer Verlag.]); Rubinstein & Svendsen (1994[Rubinstein, H. & Svendsen, J. S. (1994). Acta Chem. Scand. 48, 439-444.]); Erdemir (2012[Erdemir, S. (2012). J. Mol. Struct. 1007, 235-241.]). For the synthesis of a similar structure, see: Chakravarthy & Chand (2011[Chakravarthy, R. D. & Chand, D. (2011). J. Chem. Sci. 123, 187-199.]). For reference bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]). For hydrogen-bond motifs, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N. L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]); Etter et al. (1990[Etter, M. C., MacDonald, J. C. & Bernstein, J. (1990). Acta Cryst. B46, 256-262.]).

[Scheme 1]

Experimental

Crystal data

  • C9H10BrNO2

  • Mr = 244.08

  • Monoclinic, P 21 /n

  • a = 4.4534 (17) Å

  • b = 11.523 (4) Å

  • c = 18.212 (7) Å

  • β = 95.703 (7)°

  • V = 930.0 (6) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 4.39 mm−1

  • T = 150 K

  • 0.25 × 0.15 × 0.05 mm
Data collection

  • Bruker APEX 2000 CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.407, Tmax = 0.811

  • 7386 measured reflections

  • 1930 independent reflections

  • 1442 reflections with I > 2σ(I)

  • Rint = 0.078
Refinement

  • R[F2 > 2σ(F2)] = 0.041

  • wR(F2) = 0.092

  • S = 0.96

  • 1930 reflections

  • 119 parameters

  • H-atom parameters constrained

  • Δρmax = 0.50 e Å−3

  • Δρmin = −0.81 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
N1—H1⋯O1 0.86 1.91 2.581 (3) 134
O2—H2A⋯O1i 0.82 1.86 2.672 (4) 173
C9—H9B⋯O1ii 0.97 2.54 3.341 (4) 140
Symmetry codes: (i) [-x+{\script{3\over 2}}, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]; (ii) [-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2005[Bruker (2005). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2005[Bruker (2005). APEX2 and SAINT. Bruker 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: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]) and PLATON.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536812009749/wn2469sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812009749/wn2469Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812009749/wn2469Isup3.cml

checkCIF report


Comment top

The amino alcohol functionality is present in many classes of compounds having chemotherapeutic activity (Erdemir, 2012; Rubinstein & Svendsen, 1994; Thomas et al., 1990). In addition, phenolic compounds containing the aminoalcohol grouping in ortho positions act as excellent bidentate ligands for the formation of several metal complexes (Chakravarthy & Chand, 2011).

As an extension of our work on the reactivity of primary aminoalcohols in three-component reactions, the title compound has been isolated as a secondary product from the one-pot reaction of (2E)-3-(4-methylphenyl)-1-phenylprop-2-en-1-one (chalcone), 5-bromo-2-hydroxybenzaldehyde and aminoethanol under mild conditions.

As shown in Fig. 1, excluding methylene H atoms and the C—OH group, the molecule is essentially planar, with a maximum deviation of 0.037 (2) Å for N1. The N1—C8—C9—O2 torsion angle is -63.1 (3)°. The bond lengths (Allen et al., 1987) and angles have normal values.

The molecular structure is stabilized by a weak intramolecular N—H···O hydrogen bond, which generates an S(6) ring motif (Bernstein et al., 1995; Etter et al., 1990). In addition, intermolecular O—H···O and C—H···O hydrogen bonds (Table 1, Fig. 2) contribute to the stability of the crystal structure, linking the molecules into a three-dimensional network.

Related literature top

For background to aminoalcohol derivatives and their bioactivity, see: Thomas et al. (1990); Rubinstein & Svendsen (1994); Erdemir (2012). For the synthesis of a similar structure, see: Chakravarthy & Chand (2011). For reference bond-length data, see: Allen et al. (1987). For hydrogen-bond motifs, see: Bernstein et al. (1995); Etter et al. (1990).

Experimental top

The title compound has been obtained as a secondary product from a multicomponent reaction mixture of (2E)-3-(4-methylphenyl)-1-phenylprop-2-en-1-one (0.01mol), 5-bromo-2-hydroxybezaldehyde (0.01mol) and aminoethanol (0.01mol). The mixture was heated at 353 K in ethanol for 4 h, monitored by TLC until the reaction was completed and then cooled to room temperature. The solvent was evaporated under vacuum and the residual oil was triturated with water to afford a brown precipitate which was filtered off, washed with water and dried in a desiccator. Pale yellow plate crystals for x-ray diffraction were obtained by dissolving the product in ethanol at room temperature and leaving it to evaporate slowly over four days. 43% yield; m.p. 355 K.

Refinement top

H atoms were positioned geometrically and refined using as riding model with Csp2—H = 0.93 Å, C(methylene)—H = 0.97 Å, O—H = 0.82 Å and N—H = 0.86 Å; Uiso(H) = xUeq(C,N,O), where x = 1.5 for hydroxyl H and 1.2 for all other H atoms.

Structure description top

The amino alcohol functionality is present in many classes of compounds having chemotherapeutic activity (Erdemir, 2012; Rubinstein & Svendsen, 1994; Thomas et al., 1990). In addition, phenolic compounds containing the aminoalcohol grouping in ortho positions act as excellent bidentate ligands for the formation of several metal complexes (Chakravarthy & Chand, 2011).

As an extension of our work on the reactivity of primary aminoalcohols in three-component reactions, the title compound has been isolated as a secondary product from the one-pot reaction of (2E)-3-(4-methylphenyl)-1-phenylprop-2-en-1-one (chalcone), 5-bromo-2-hydroxybenzaldehyde and aminoethanol under mild conditions.

As shown in Fig. 1, excluding methylene H atoms and the C—OH group, the molecule is essentially planar, with a maximum deviation of 0.037 (2) Å for N1. The N1—C8—C9—O2 torsion angle is -63.1 (3)°. The bond lengths (Allen et al., 1987) and angles have normal values.

The molecular structure is stabilized by a weak intramolecular N—H···O hydrogen bond, which generates an S(6) ring motif (Bernstein et al., 1995; Etter et al., 1990). In addition, intermolecular O—H···O and C—H···O hydrogen bonds (Table 1, Fig. 2) contribute to the stability of the crystal structure, linking the molecules into a three-dimensional network.

For background to aminoalcohol derivatives and their bioactivity, see: Thomas et al. (1990); Rubinstein & Svendsen (1994); Erdemir (2012). For the synthesis of a similar structure, see: Chakravarthy & Chand (2011). For reference bond-length data, see: Allen et al. (1987). For hydrogen-bond motifs, see: Bernstein et al. (1995); Etter et al. (1990).

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure, showing displacement ellipsoids drawn at the 50% probability level. Hydrogen atoms are shown as spheres of arbitrary radius.
[Figure 2] Fig. 2. View of the packing down the a axis. Dashed lines indicate hydrogen bonds. H atoms not involved in hydrogen bonding have been omitted for clarity.
(6Z)-4-Bromo-6-{[(2-hydroxyethyl)amino]methylidene}cyclohexa- 2,4-dien-1-one top
Crystal data top
C9H10BrNO2F(000) = 488
Mr = 244.08Dx = 1.743 Mg m−3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 972 reflections
a = 4.4534 (17) Åθ = 3.5–28.3°
b = 11.523 (4) ŵ = 4.39 mm−1
c = 18.212 (7) ÅT = 150 K
β = 95.703 (7)°Plate, pale yellow
V = 930.0 (6) Å30.25 × 0.15 × 0.05 mm
Z = 4
Data collection top
Bruker APEX 2000 CCD area-detector
diffractometer		1930 independent reflections
Radiation source: fine-focus sealed tube1442 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.078
phi and ω scansθmax = 26.5°, θmin = 2.1°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		h = −5→5
Tmin = 0.407, Tmax = 0.811k = −14→14
7386 measured reflectionsl = −22→22
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)] = 0.041Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.092H-atom parameters constrained
S = 0.96 w = 1/[σ2(Fo2) + (0.0441P)2]
where P = (Fo2 + 2Fc2)/3
1930 reflections(Δ/σ)max = 0.001
119 parametersΔρmax = 0.50 e Å−3
0 restraintsΔρmin = −0.81 e Å−3
Crystal data top
C9H10BrNO2V = 930.0 (6) Å3
Mr = 244.08Z = 4
Monoclinic, P21/nMo Kα radiation
a = 4.4534 (17) ŵ = 4.39 mm−1
b = 11.523 (4) ÅT = 150 K
c = 18.212 (7) Å0.25 × 0.15 × 0.05 mm
β = 95.703 (7)°
Data collection top
Bruker APEX 2000 CCD area-detector
diffractometer		1930 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		1442 reflections with I > 2σ(I)
Tmin = 0.407, Tmax = 0.811Rint = 0.078
7386 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0410 restraints
wR(F2) = 0.092H-atom parameters constrained
S = 0.96Δρmax = 0.50 e Å−3
1930 reflectionsΔρmin = −0.81 e Å−3
119 parameters
Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

Refinement. Refinement on F2 for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The observed criterion of F2 > σ(F2) is used only for calculating -R-factor-obs 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*/Ueq
Br11.18634 (9)0.87511 (3)0.62311 (2)0.0421 (1)
O10.7253 (5)0.62015 (18)0.34691 (14)0.0337 (7)
O20.4433 (6)1.0017 (2)0.24200 (13)0.0405 (8)
N10.3527 (5)0.7886 (2)0.31526 (14)0.0281 (8)
C11.0339 (8)0.7961 (3)0.53566 (17)0.0307 (10)
C21.1550 (7)0.6880 (3)0.51979 (19)0.0328 (11)
C31.0572 (8)0.6302 (3)0.45664 (19)0.0306 (10)
C40.8236 (7)0.6747 (3)0.40514 (19)0.0267 (9)
C50.7034 (7)0.7865 (3)0.42349 (17)0.0263 (10)
C60.8125 (7)0.8450 (3)0.48844 (18)0.0289 (10)
C70.4695 (7)0.8372 (3)0.37491 (18)0.0277 (10)
C80.1263 (7)0.8437 (3)0.26310 (19)0.0326 (11)
C90.2721 (8)0.9117 (3)0.20525 (18)0.0314 (11)
H10.411300.719700.305500.0340*
H21.304200.655200.552700.0390*
H2A0.549101.032600.213200.0610*
H31.145600.559500.446800.0370*
H60.733700.917000.499200.0350*
H70.397000.909700.387000.0330*
H8A0.003100.895400.289600.0390*
H8B−0.004500.784700.239200.0390*
H9A0.401800.861500.179500.0380*
H9B0.118900.944000.169500.0380*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.0616 (3)0.0314 (2)0.0309 (2)−0.0066 (2)−0.0074 (2)0.0005 (2)
O10.0400 (13)0.0243 (12)0.0361 (13)0.0005 (10)0.0008 (10)−0.0076 (11)
O20.0487 (15)0.0422 (15)0.0306 (13)−0.0192 (12)0.0033 (11)−0.0005 (12)
N10.0275 (15)0.0242 (14)0.0326 (15)−0.0018 (11)0.0035 (12)0.0017 (12)
C10.0412 (19)0.0245 (17)0.0261 (17)−0.0088 (15)0.0017 (14)0.0002 (14)
C20.0353 (19)0.0257 (18)0.0366 (19)−0.0015 (15)−0.0010 (15)0.0105 (15)
C30.0368 (18)0.0183 (15)0.0369 (19)−0.0004 (15)0.0045 (14)0.0048 (14)
C40.0269 (16)0.0221 (16)0.0321 (17)−0.0048 (14)0.0080 (13)0.0021 (15)
C50.0285 (17)0.0216 (16)0.0295 (17)−0.0022 (13)0.0067 (13)0.0029 (13)
C60.0352 (18)0.0221 (17)0.0300 (17)−0.0014 (14)0.0068 (14)−0.0014 (13)
C70.0304 (17)0.0227 (16)0.0309 (17)−0.0036 (14)0.0080 (14)0.0012 (14)
C80.0264 (17)0.0322 (19)0.0382 (19)−0.0009 (14)−0.0023 (14)−0.0010 (16)
C90.0357 (19)0.0294 (18)0.0286 (18)−0.0004 (15)0.0008 (14)−0.0013 (14)
Geometric parameters (Å, º) top
Br1—C11.900 (3)C5—C61.406 (5)
O1—C41.272 (4)C5—C71.423 (5)
O2—C91.415 (4)C8—C91.511 (5)
O2—H2A0.8200C2—H20.9300
N1—C81.460 (4)C3—H30.9300
N1—C71.285 (4)C6—H60.9300
N1—H10.8600C7—H70.9300
C1—C21.399 (5)C8—H8A0.9700
C1—C61.364 (5)C8—H8B0.9700
C2—C31.363 (5)C9—H9A0.9700
C3—C41.425 (5)C9—H9B0.9700
C4—C51.447 (5)
C9—O2—H2A109.00C1—C2—H2120.00
C7—N1—C8123.8 (3)C3—C2—H2120.00
C7—N1—H1118.00C2—C3—H3119.00
C8—N1—H1118.00C4—C3—H3119.00
C2—C1—C6120.5 (3)C1—C6—H6120.00
Br1—C1—C2119.1 (2)C5—C6—H6120.00
Br1—C1—C6120.4 (3)N1—C7—H7118.00
C1—C2—C3120.8 (3)C5—C7—H7118.00
C2—C3—C4122.1 (3)N1—C8—H8A109.00
O1—C4—C3122.6 (3)N1—C8—H8B109.00
O1—C4—C5121.9 (3)C9—C8—H8A109.00
C3—C4—C5115.5 (3)C9—C8—H8B109.00
C6—C5—C7119.8 (3)H8A—C8—H8B108.00
C4—C5—C6121.1 (3)O2—C9—H9A110.00
C4—C5—C7119.1 (3)O2—C9—H9B110.00
C1—C6—C5120.0 (3)C8—C9—H9A110.00
N1—C7—C5123.8 (3)C8—C9—H9B110.00
N1—C8—C9111.3 (3)H9A—C9—H9B108.00
O2—C9—C8107.4 (3)
C8—N1—C7—C5−176.0 (3)O1—C4—C5—C6179.3 (3)
C7—N1—C8—C989.7 (4)C3—C4—C5—C7180.0 (3)
Br1—C1—C6—C5179.3 (2)O1—C4—C5—C7−0.3 (5)
C2—C1—C6—C50.3 (5)C3—C4—C5—C6−0.5 (5)
Br1—C1—C2—C3−178.2 (3)C4—C5—C6—C1−0.5 (5)
C6—C1—C2—C30.8 (5)C6—C5—C7—N1−178.5 (3)
C1—C2—C3—C4−1.8 (5)C7—C5—C6—C1179.2 (3)
C2—C3—C4—O1−178.2 (3)C4—C5—C7—N11.1 (5)
C2—C3—C4—C51.6 (5)N1—C8—C9—O2−63.1 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O10.861.912.581 (3)134
O2—H2A···O1i0.821.862.672 (4)173
C9—H9B···O1ii0.972.543.341 (4)140
Symmetry codes: (i) −x+3/2, y+1/2, −z+1/2; (ii) −x+1/2, y+1/2, −z+1/2.

Experimental details

Crystal data
Chemical formulaC9H10BrNO2
Mr244.08
Crystal system, space groupMonoclinic, P21/n
Temperature (K)150
a, b, c (Å)4.4534 (17), 11.523 (4), 18.212 (7)
β (°) 95.703 (7)
V (Å3)930.0 (6)
Z4
Radiation typeMo Kα
µ (mm−1)4.39
Crystal size (mm)0.25 × 0.15 × 0.05
Data collection
DiffractometerBruker APEX 2000 CCD area-detector
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.407, 0.811
No. of measured, independent and
observed [I > 2σ(I)] reflections		7386, 1930, 1442
Rint0.078
(sin θ/λ)max (Å−1)0.628
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.041, 0.092, 0.96
No. of reflections1930
No. of parameters119
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.50, −0.81

Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009), WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O10.861.912.581 (3)134
O2—H2A···O1i0.821.862.672 (4)173
C9—H9B···O1ii0.972.543.341 (4)140
Symmetry codes: (i) −x+3/2, y+1/2, −z+1/2; (ii) −x+1/2, y+1/2, −z+1/2.
 

Acknowledgements

The authors are grateful to the Egyptian Higher Education Authority for their financial support of this research project. Our thanks are also extended to Manchester Metropolitan University for facilitating this study.

References

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ISSN: 2056-9890
Volume 68| Part 4| April 2012| Page o1020
doi:10.1107/S1600536812009749
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