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

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ISSN: 2056-9890

Bis­(2-hy­dr­oxy­eth­yl)ammonium 2-bromo­phenolate

aSchool of Chemistry, Molecular Sciences Institute, University of the Witwatersrand, Private Bag 3, Wits 2050, Johannesburg, South Africa
*Correspondence e-mail: Alvaro.DeSousa@wits.ac.za

(Received 11 July 2012; accepted 27 July 2012; online 1 August 2012)

In the crystal structure of the 1:1 title salt, C4H12NO2+·C6H4BrO, hydrogen-bonding inter­actions originate from the ammonium cation, which adopts a syn conformation. A gauche relationship between the C—O and C—N bonds of the 2-hy­droxy­ethyl fragments also facilitates O—H⋯O inter­actions of bis­(2-hy­droxy­eth­yl)ammonium cation chains to phenolate O atoms. The resulting double-ion chains along [100] are further linked by N—H⋯O inter­actions, forming chains parallel to [110].

Related literature

For structures of related 2-haloethyl­ammonium salts and properties of these salts, see: Cody (1981[Cody, V. (1981). Acta Cryst. B37, 1685-1689.]); Cody & Strong (1980[Cody, V. & Strong, P. D. (1980). Acta Cryst. B36, 1723-1726.]); Prout et al. (1988[Prout, K., Fail, J., Jones, R. M., Warner, R. E. & Emmett, J. C. (1988). J. Chem. Soc. Perkin Trans. 2, pp. 265-284.]); Castellari & Ottani (1995[Castellari, C. & Ottani, S. (1995). Acta Cryst. C51, 2612-2615.]); de Sousa et al. (2010a[Sousa, A. S. de, Hlam, Z., Fernandes, M. A. & Marques, H. M. (2010a). Acta Cryst. C66, o229-o232.],b[Sousa, A. S. de, Hlam, Z., Fernandes, M. A. & Marques, H. M. (2010b). Acta Cryst. C66, o553-o556.]); Larsen et al. (2005[Larsen, F. K., Muryn, C. A., Overgaard, J., Timco, G. A. & Winpenny, R. E. P. (2005). Acta Cryst. E61, m1525-m1527.]); Mootz et al. (1989[Mootz, D., Brodalla, D. & Wiebcke, M. (1989). Acta Cryst. C45, 754-757.]). For graph-set 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.]).

[Scheme 1]

Experimental

Crystal data
  • C4H12NO2+·C6H4BrO

  • Mr = 278.15

  • Monoclinic, P 21

  • a = 8.0592 (1) Å

  • b = 7.6653 (1) Å

  • c = 9.7659 (2) Å

  • β = 107.250 (1)°

  • V = 576.16 (2) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 3.56 mm−1

  • T = 173 K

  • 0.48 × 0.21 × 0.20 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • Absorption correction: gaussian (XPREP; Bruker, 2005[Bruker (2005). APEX2, SAINT-NT and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.280, Tmax = 0.537

  • 11689 measured reflections

  • 2784 independent reflections

  • 2638 reflections with I > 2σ(I)

  • Rint = 0.033

Refinement
  • R[F2 > 2σ(F2)] = 0.018

  • wR(F2) = 0.042

  • S = 1.05

  • 2784 reflections

  • 149 parameters

  • 1 restraint

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

  • Δρmax = 0.17 e Å−3

  • Δρmin = −0.28 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 1290 Friedel pairs

  • Flack parameter: −0.012 (5)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O2—H2⋯O1 0.83 (2) 1.83 (2) 2.6393 (16) 165 (2)
O3—H3⋯O2i 0.84 1.87 2.7010 (18) 171
N1—H1A⋯O1ii 0.969 (18) 1.789 (19) 2.738 (2) 165.7 (16)
N1—H1B⋯O1 0.93 (2) 1.91 (2) 2.8259 (19) 169 (2)
Symmetry codes: (i) x-1, y, z; (ii) [-x+1, y+{\script{1\over 2}}, -z+1].

Data collection: APEX2 (Bruker, 2005[Bruker (2005). APEX2, SAINT-NT and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT-NT (Bruker, 2005[Bruker (2005). APEX2, SAINT-NT and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT-NT; 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: 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


Comment top

The molecular structure (Fig. 1) of the 1:1 salt of 2-bromophenol with diethanolamine (DEA) is reported. Our interest in studying DEA is aimed at developing amino alcohols as supramolecules in a crystal engineering strategy, for template self-assembly of these compounds in supramolecular structures. Directional hydrogen-bonding patterns associated with DEA have labeled this compound a potential supramolecule. It is known to aggregate into tubular columns (Mootz et al., 1989); the behaviour is emulated by C— and N—alkylated derivatives (de Sousa et al., 2010a,b). Specific O—H···O interactions of the 2-hydroxyalkyl groups contribute significantly towards tubular aggregation in alkylated derivatives of this compound. These hydrogen bonds also feature prominently in salts of DEA elucidating binding modes of thyroid hormones to transport proteins (Cody, 1981; Cody & Strong, 1980; Prout et al., 1988); the template synthesis of heterometallic wheels (Larsen et al., 2005); and in studies aimed at correlating structural and pharmacological properties of anti-inflammatory drugs (Castellari & Ottani, 1995).

O—H···O hydrogen bonds are highly influential in the molecular structure reported here for the 2-bromophenol (1:1) salt with DEA. The unitary level C(8) chain (Bernstein et al., 1995), described by O3—H3···O2 hydrogen bonds along [100], defines the backbone of the crystal structure (Fig. 2 and Table 1). In these chains syn conformations of the bis(2-hydroxyethyl) ammonium cations enjoy gauche relationships between C—O and C—N bonds, enabling further O—H···O and N—H···O hydrogen bonds of this supramolecular synthon. Hydroxyethyl O atom O2 acts as a weakly bifurcated H-donor, via H2, to phenolate O1 and Br1 atoms (Table 1). The hydrogen bonding array of the double-ion pair is completed by the N1—H1B···O1 interaction involving the ammonium N1 atom acting as a hydrogen donor, via H1B, to the phenolate oxygen atom O1. The combined O2—H2···O1 and N1—H1B···O1 interactions describe a R21(7) ring motif (Fig. 2) at the binary level (Bernstein et al., 1995). Chains of double-ion pairs along [100] are linked by N1—H1A···O1 interactions (Table 1) to form layers parallel to the ab plane (Fig. 3). Within these layers N—H···O interactions define C21(4) and C21(7) motifs along [010] (Fig. 4) when combined with interactions N1—H1B···O1 and O2—H2···O1, respectively.

Related literature top

For structures of related 2-haloethylammonium salts and properties of these salts, see: Cody (1981); Cody & Strong (1980); Prout et al. (1988); Castellari & Ottani (1995); de Sousa et al. (2010a,b); Larsen et al. (2005); Mootz et al. (1989). For graph-set motifs, see: Bernstein et al. (1995).

Experimental top

Diethanolamine (0.501 g, 4.8 mmol) was stirred in 20 ml of dimethylformamide. To this solution, sodium carbonate (0.504 g, 4.75 mmol) and 2-bromophenol (0.823 g, 4.76 mmol) was added with continuous stirring. The reaction mixture was allowed to stir for an additional 24 hours under ambient conditions. The mixture was filtered and the solvent removed under reduced pressure, to yield a clear viscous oil that crystallized upon standing.

Refinement top

Hydrogen atoms were visible in the difference maps, but those bonded to C atoms were positioned geometrically and refined as riding atoms, with C—H = 0.99 Å (CH2) or 0.95 Å (aromatic CH), as well as H3, bonded to O3, with O3—H3 bond length fixed to 0.84 Å. Isotropic displacement parameters for these H atoms were defined as Uiso(H) = 1.2Ueq(parent C atom) and Uiso(H3) = 1.5Ueq(O3). Other H atoms (H1A, H1B and H2), which are involved in hydrogen bonds, were refined freely.

Computing details top

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

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound, showing displacement ellipsoids at the 50% probability level.
[Figure 2] Fig. 2. Chains along [100] defined by intermolecular O—H···O hydrogen bonds. Symmetry codes: (i) x, y, z; (ii) 1+x, y, z; (iii) -1+x, y, z.
[Figure 3] Fig. 3. Layers parallel to (110) formed by hydrogen bonding double-ion chains along [100].
[Figure 4] Fig. 4. Binary C21(4) and C21(7) motifs along [010] described by N—H···O and O—H···O interactions originating at the bis(2-hydroxyethyl)ammonium cation.
bis(2-hydroxyethyl)ammonium 2-bromophenolate top
Crystal data top
C4H12NO2+·C6H4BrOF(000) = 284
Mr = 278.15Dx = 1.603 Mg m3
Monoclinic, P21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ybCell parameters from 8333 reflections
a = 8.0592 (1) Åθ = 2.2–28.2°
b = 7.6653 (1) ŵ = 3.56 mm1
c = 9.7659 (2) ÅT = 173 K
β = 107.250 (1)°Needle, colourless
V = 576.16 (2) Å30.48 × 0.21 × 0.20 mm
Z = 2
Data collection top
Bruker APEXII CCD
diffractometer
2784 independent reflections
Radiation source: fine-focus sealed tube2638 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.033
ϕ and ω scansθmax = 28.0°, θmin = 2.2°
Absorption correction: gaussian
(XPREP; Bruker, 2005)
h = 1010
Tmin = 0.280, Tmax = 0.537k = 1010
11689 measured reflectionsl = 1212
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.018H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.042 w = 1/[σ2(Fo2) + (0.025P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.05(Δ/σ)max = 0.001
2784 reflectionsΔρmax = 0.17 e Å3
149 parametersΔρmin = 0.28 e Å3
1 restraintAbsolute structure: Flack (1983), 1290 Friedel pairs
0 constraintsAbsolute structure parameter: 0.012 (5)
Primary atom site location: structure-invariant direct methods
Crystal data top
C4H12NO2+·C6H4BrOV = 576.16 (2) Å3
Mr = 278.15Z = 2
Monoclinic, P21Mo Kα radiation
a = 8.0592 (1) ŵ = 3.56 mm1
b = 7.6653 (1) ÅT = 173 K
c = 9.7659 (2) Å0.48 × 0.21 × 0.20 mm
β = 107.250 (1)°
Data collection top
Bruker APEXII CCD
diffractometer
2784 independent reflections
Absorption correction: gaussian
(XPREP; Bruker, 2005)
2638 reflections with I > 2σ(I)
Tmin = 0.280, Tmax = 0.537Rint = 0.033
11689 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.018H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.042Δρmax = 0.17 e Å3
S = 1.05Δρmin = 0.28 e Å3
2784 reflectionsAbsolute structure: Flack (1983), 1290 Friedel pairs
149 parametersAbsolute structure parameter: 0.012 (5)
1 restraint
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.4737 (2)0.35547 (19)0.23985 (15)0.0163 (3)
C20.2924 (2)0.3582 (2)0.17355 (16)0.0204 (3)
H2A0.22080.42460.21570.025*
C30.2168 (2)0.2669 (3)0.04897 (18)0.0278 (4)
H3A0.09420.27090.00760.033*
C40.3155 (3)0.1699 (2)0.01670 (18)0.0299 (4)
H40.26190.10800.10280.036*
C50.4937 (3)0.1639 (2)0.04447 (18)0.0263 (4)
H50.56370.09720.00090.032*
C60.56985 (19)0.2557 (3)0.16984 (15)0.0191 (3)
O10.54554 (14)0.44173 (13)0.36173 (11)0.0181 (2)
Br10.815421 (18)0.24105 (3)0.250455 (16)0.02891 (5)
C70.7822 (2)0.7869 (2)0.46980 (18)0.0222 (4)
H7A0.88070.86990.49080.027*
H7B0.76000.75830.56170.027*
C80.6234 (2)0.8745 (2)0.37228 (18)0.0210 (3)
H8A0.62570.99990.39710.025*
H8B0.62660.86540.27200.025*
C90.3024 (2)0.8634 (2)0.26948 (17)0.0235 (4)
H9A0.31740.98970.25570.028*
H9B0.29300.80350.17770.028*
C100.1394 (3)0.8345 (3)0.3100 (2)0.0235 (4)
H10A0.14580.89770.39980.028*
H10B0.03790.87860.23340.028*
N10.4570 (2)0.7953 (2)0.38319 (17)0.0168 (3)
O20.83024 (16)0.63195 (16)0.41133 (14)0.0241 (3)
O30.1216 (2)0.65362 (19)0.3294 (2)0.0379 (4)
H30.03410.63570.35750.057*
H1A0.449 (2)0.829 (2)0.4768 (19)0.017 (4)*
H20.752 (3)0.557 (3)0.396 (2)0.038 (6)*
H1B0.473 (3)0.676 (3)0.3791 (19)0.012 (5)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0227 (8)0.0118 (7)0.0152 (7)0.0009 (6)0.0069 (6)0.0028 (5)
C20.0243 (9)0.0182 (7)0.0196 (8)0.0012 (6)0.0077 (6)0.0030 (6)
C30.0265 (8)0.0303 (12)0.0213 (7)0.0000 (8)0.0008 (6)0.0043 (7)
C40.0424 (11)0.0284 (8)0.0144 (8)0.0062 (8)0.0016 (8)0.0026 (7)
C50.0398 (11)0.0213 (8)0.0217 (9)0.0017 (7)0.0150 (8)0.0010 (7)
C60.0211 (6)0.0157 (8)0.0219 (7)0.0016 (8)0.0087 (5)0.0026 (8)
O10.0192 (6)0.0182 (5)0.0170 (5)0.0016 (4)0.0055 (4)0.0027 (4)
Br10.02163 (8)0.02397 (8)0.04356 (10)0.00235 (9)0.01340 (6)0.00094 (11)
C70.0176 (8)0.0238 (10)0.0252 (8)0.0027 (6)0.0063 (6)0.0042 (6)
C80.0210 (8)0.0180 (7)0.0267 (8)0.0036 (6)0.0111 (7)0.0011 (6)
C90.0244 (9)0.0243 (8)0.0191 (8)0.0031 (7)0.0022 (7)0.0042 (6)
C100.0195 (10)0.0225 (9)0.0273 (10)0.0044 (7)0.0050 (8)0.0048 (8)
N10.0162 (7)0.0151 (6)0.0201 (7)0.0009 (4)0.0070 (5)0.0006 (4)
O20.0187 (6)0.0195 (6)0.0356 (7)0.0023 (5)0.0104 (5)0.0033 (5)
O30.0285 (9)0.0231 (8)0.0722 (12)0.0009 (6)0.0306 (8)0.0068 (7)
Geometric parameters (Å, º) top
C1—O11.3344 (18)C7—H7B0.9900
C1—C61.403 (2)C8—N11.505 (2)
C1—C21.411 (2)C8—H8A0.9900
C2—C31.379 (2)C8—H8B0.9900
C2—H2A0.9500C9—C101.496 (3)
C3—C41.378 (3)C9—N11.496 (2)
C3—H3A0.9500C9—H9A0.9900
C4—C51.383 (3)C9—H9B0.9900
C4—H40.9500C10—O31.412 (2)
C5—C61.388 (2)C10—H10A0.9900
C5—H50.9500C10—H10B0.9900
C6—Br11.9041 (15)N1—H1A0.969 (18)
C7—O21.4204 (19)N1—H1B0.93 (2)
C7—C81.508 (2)O2—H20.83 (2)
C7—H7A0.9900O3—H30.8400
O1—C1—C6123.26 (14)N1—C8—H8A109.1
O1—C1—C2121.22 (14)C7—C8—H8A109.1
C6—C1—C2115.53 (14)N1—C8—H8B109.1
C3—C2—C1121.58 (16)C7—C8—H8B109.1
C3—C2—H2A119.2H8A—C8—H8B107.8
C1—C2—H2A119.2C10—C9—N1110.82 (14)
C4—C3—C2121.27 (17)C10—C9—H9A109.5
C4—C3—H3A119.4N1—C9—H9A109.5
C2—C3—H3A119.4C10—C9—H9B109.5
C3—C4—C5119.06 (16)N1—C9—H9B109.5
C3—C4—H4120.5H9A—C9—H9B108.1
C5—C4—H4120.5O3—C10—C9108.25 (17)
C4—C5—C6119.67 (16)O3—C10—H10A110.0
C4—C5—H5120.2C9—C10—H10A110.0
C6—C5—H5120.2O3—C10—H10B110.0
C5—C6—C1122.89 (15)C9—C10—H10B110.0
C5—C6—Br1117.92 (13)H10A—C10—H10B108.4
C1—C6—Br1119.19 (12)C9—N1—C8111.74 (13)
O2—C7—C8113.57 (13)C9—N1—H1A109.6 (10)
O2—C7—H7A108.9C8—N1—H1A105.5 (10)
C8—C7—H7A108.9C9—N1—H1B114.2 (12)
O2—C7—H7B108.9C8—N1—H1B104.8 (14)
C8—C7—H7B108.9H1A—N1—H1B110.6 (16)
H7A—C7—H7B107.7C7—O2—H2111.9 (16)
N1—C8—C7112.52 (13)C10—O3—H3109.5
O1—C1—C2—C3178.80 (15)C2—C1—C6—C50.6 (2)
C6—C1—C2—C30.6 (2)O1—C1—C6—Br10.1 (2)
C1—C2—C3—C40.5 (3)C2—C1—C6—Br1179.51 (11)
C2—C3—C4—C50.3 (3)O2—C7—C8—N182.70 (18)
C3—C4—C5—C60.3 (3)N1—C9—C10—O359.0 (2)
C4—C5—C6—C10.4 (3)C10—C9—N1—C8160.34 (16)
C4—C5—C6—Br1179.38 (13)C7—C8—N1—C9170.68 (14)
O1—C1—C6—C5178.81 (15)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···O10.83 (2)1.83 (2)2.6393 (16)165 (2)
O3—H3···O2i0.841.872.7010 (18)171
N1—H1A···O1ii0.969 (18)1.789 (19)2.738 (2)165.7 (16)
N1—H1B···O10.93 (2)1.91 (2)2.8259 (19)169 (2)
O2—H2···Br10.83 (2)2.92 (2)3.3690 (13)115.6 (18)
Symmetry codes: (i) x1, y, z; (ii) x+1, y+1/2, z+1.

Experimental details

Crystal data
Chemical formulaC4H12NO2+·C6H4BrO
Mr278.15
Crystal system, space groupMonoclinic, P21
Temperature (K)173
a, b, c (Å)8.0592 (1), 7.6653 (1), 9.7659 (2)
β (°) 107.250 (1)
V3)576.16 (2)
Z2
Radiation typeMo Kα
µ (mm1)3.56
Crystal size (mm)0.48 × 0.21 × 0.20
Data collection
DiffractometerBruker APEXII CCD
diffractometer
Absorption correctionGaussian
(XPREP; Bruker, 2005)
Tmin, Tmax0.280, 0.537
No. of measured, independent and
observed [I > 2σ(I)] reflections
11689, 2784, 2638
Rint0.033
(sin θ/λ)max1)0.660
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.018, 0.042, 1.05
No. of reflections2784
No. of parameters149
No. of restraints1
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.17, 0.28
Absolute structureFlack (1983), 1290 Friedel pairs
Absolute structure parameter0.012 (5)

Computer programs: APEX2 (Bruker, 2005), SAINT-NT (Bruker, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···O10.83 (2)1.83 (2)2.6393 (16)165 (2)
O3—H3···O2i0.841.872.7010 (18)171.0
N1—H1A···O1ii0.969 (18)1.789 (19)2.738 (2)165.7 (16)
N1—H1B···O10.93 (2)1.91 (2)2.8259 (19)169 (2)
Symmetry codes: (i) x1, y, z; (ii) x+1, y+1/2, z+1.
 

Acknowledgements

This work was funded in part by a grant through the Department of Science and Technology/National Research Foundation South Africa Research Chairs initiative to HMM.

References

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