Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270110009820/fg3157sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270110009820/fg3157Isup2.hkl |
CCDC reference: 774921
Ethanolamine and cyclohexene oxide were used as obtained from Merck and Aldrich, respectively. Equimolar quantities of ethanolamine (1 g, 16.4 mmol) and cyclohexene oxide (1.61 g, 16.4 mmol) were added to a round-bottomed flask containing absolute ethanol (10 ml). A CaCl2 drying tube and condenser were fitted to the flask and the mixture was refluxed with stirring at 358 K for 48 h. After completion of the reaction, the solvent was removed under reduced pressure to yield a yellow oil. The oil was dissolved in deionised water (15 ml) and washed with chloroform (30 ml). Upon removal of the solvent under reduced pressure the aqueous layer yielded a light-yellow oil, which was characterized by NMR and FAB-MS to be the product 2-[(2-hydroxyethyl)amino]cyclohexanol, (I). Crystals of (I) formed from the crude oil and the extractant when left unattended for several days (yield 96%). Spectroscopic analysis: 1H NMR (D2O, 300 MHz, δ, p.p.m.): 3.61 (2H, m, CH2), 3.28 (1H, m, CH), 2.66 (2H, m, CH2), 2.31 (1H, m, CH), 1.89 (2H, m, CH2), 1.62 (2H, m, CH2), 1.09 (4H, m, 2 × CH2); 13C NMR (CDCl3, 300 MHz, δ, p.p.m.): 73.42, 63.15, 60.95, 48.30, 34.16, 30.13, 24.73, 24.63; MS, m/z (FAB) 160 (M+, 100%)
H atoms were first located in the difference map and then positioned geometrically. They were allowed to ride on their respective parent atoms, with C—H = 1.00 (CH) or 0.99 Å (CH2), N—H = 0.92 Å and O—H = 0.84 Å, and with Uiso(H) = 1.2Ueq(C). The disordered hydroxyethyl groups were refined over two positions with similarity restraints, of standard uncertainty 0.001 Å, applied to chemically equivalent bond lengths and angles for disordered hydroxyethyl groups C17—C18—O12 and C27—C28—O22. The N11—C17 and N11—C27 bonds were restrained to have similar lengths within an effective standard uncertainty of 0.001 Å. Atom C27 was restrained to approximate isotropic behaviour with a standard uncertainty of 0.003 Å2. A rigid bond restraint with a standard uncertainty of 0.003 Å was applied to atoms C27, C28 and O22 of the minor conformation of the hydroxyethyl group, of site occupancy 0.264 (2), because the components of the displacement parameters along bond directions between atoms C27 and C28 and C28 and O22 were irregular. In addition, similarity restraints were applied to the displacement parameters of the atoms of the minor conformation of the hydroxyethyl group with a standard uncertainty of 0.01 Å2.
Data collection: SMART [APEX2?] (Bruker, 2005); cell refinement: SMART [APEX2?] (Bruker, 2005); data reduction: SAINT [SAINT-Plus?] (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008) and WinGX (Farrugia, 1997); molecular graphics: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).
C8H17NO2 | Z = 4 |
Mr = 159.23 | F(000) = 352 |
Triclinic, P1 | Dx = 1.198 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 9.4334 (2) Å | Cell parameters from 5097 reflections |
b = 10.0280 (3) Å | θ = 2.2–28.3° |
c = 10.4651 (3) Å | µ = 0.09 mm−1 |
α = 112.954 (1)° | T = 173 K |
β = 92.429 (1)° | Plate, colourless |
γ = 102.055 (1)° | 0.48 × 0.40 × 0.15 mm |
V = 883.02 (4) Å3 |
Bruker SMART [APEXII?] CCD area-detector diffractometer | 3495 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.046 |
Graphite monochromator | θmax = 28.0°, θmin = 2.1° |
ϕ and ω scans | h = −12→12 |
20934 measured reflections | k = −13→13 |
4253 independent reflections | l = −13→13 |
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)] = 0.037 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.103 | H-atom parameters constrained |
S = 1.03 | w = 1/[σ2(Fo2) + (0.0496P)2 + 0.2058P] where P = (Fo2 + 2Fc2)/3 |
4253 reflections | (Δ/σ)max < 0.001 |
232 parameters | Δρmax = 0.33 e Å−3 |
31 restraints | Δρmin = −0.19 e Å−3 |
C8H17NO2 | γ = 102.055 (1)° |
Mr = 159.23 | V = 883.02 (4) Å3 |
Triclinic, P1 | Z = 4 |
a = 9.4334 (2) Å | Mo Kα radiation |
b = 10.0280 (3) Å | µ = 0.09 mm−1 |
c = 10.4651 (3) Å | T = 173 K |
α = 112.954 (1)° | 0.48 × 0.40 × 0.15 mm |
β = 92.429 (1)° |
Bruker SMART [APEXII?] CCD area-detector diffractometer | 3495 reflections with I > 2σ(I) |
20934 measured reflections | Rint = 0.046 |
4253 independent reflections |
R[F2 > 2σ(F2)] = 0.037 | 31 restraints |
wR(F2) = 0.103 | H-atom parameters constrained |
S = 1.03 | Δρmax = 0.33 e Å−3 |
4253 reflections | Δρmin = −0.19 e Å−3 |
232 parameters |
Experimental. Intensity data were collected on a Bruker APEXII CCD area-detector diffractometer with graphite monochromated Mo Kα radiation (50 kV, 30 mA) using the APEX2 (Bruker, 2005a) data collection software. The collection method involved ω scans of width 0.5° and 512 × 512 bit data frames. Data reduction was carried out using the program SAINT-Plus (Bruker, 2005). The crystal structure was solved by direct methods using SHELXTL (Sheldrick, 2008). Non-H atoms were first refined isotropically, followed by anisotropic refinement by full-matrix least-squares calculations based on F2 using SHELXTL. |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 | Occ. (<1) | |
C1 | 0.39086 (10) | 0.34950 (11) | 0.15841 (10) | 0.0200 (2) | |
H1A | 0.4014 | 0.4098 | 0.2617 | 0.024* | |
C2 | 0.28564 (11) | 0.19757 (11) | 0.12241 (10) | 0.0219 (2) | |
H2A | 0.2781 | 0.1362 | 0.0196 | 0.026* | |
C3 | 0.13388 (11) | 0.21742 (13) | 0.15719 (12) | 0.0277 (2) | |
H3A | 0.0660 | 0.1183 | 0.1310 | 0.033* | |
H3B | 0.1390 | 0.2749 | 0.2593 | 0.033* | |
C4 | 0.07589 (12) | 0.29927 (14) | 0.07892 (12) | 0.0301 (3) | |
H4A | −0.0210 | 0.3139 | 0.1054 | 0.036* | |
H4B | 0.0632 | 0.2378 | −0.0232 | 0.036* | |
C5 | 0.18021 (12) | 0.45048 (13) | 0.11260 (12) | 0.0295 (2) | |
H5A | 0.1838 | 0.5161 | 0.2126 | 0.035* | |
H5B | 0.1433 | 0.4981 | 0.0555 | 0.035* | |
C6 | 0.33419 (12) | 0.43401 (12) | 0.08271 (11) | 0.0249 (2) | |
H6A | 0.3329 | 0.3801 | −0.0194 | 0.030* | |
H6B | 0.4011 | 0.5343 | 0.1131 | 0.030* | |
C7 | 0.27026 (12) | −0.03677 (12) | 0.15081 (13) | 0.0318 (3) | |
H7A | 0.2536 | −0.0838 | 0.0471 | 0.038* | |
H7B | 0.1736 | −0.0447 | 0.1845 | 0.038* | |
C8 | 0.35789 (14) | −0.11912 (13) | 0.20404 (13) | 0.0347 (3) | |
H8A | 0.3786 | −0.0686 | 0.3075 | 0.042* | |
H8B | 0.2989 | −0.2221 | 0.1788 | 0.042* | |
N1 | 0.34610 (10) | 0.12143 (10) | 0.19865 (9) | 0.0238 (2) | |
H3 | 0.4434 | 0.1285 | 0.1883 | 0.029* | |
O1 | 0.53151 (8) | 0.33006 (8) | 0.12066 (8) | 0.02352 (17) | |
H1 | 0.5906 | 0.3568 | 0.1935 | 0.035* | |
O2 | 0.49166 (9) | −0.12558 (10) | 0.14837 (9) | 0.0385 (2) | |
H2 | 0.4752 | −0.1892 | 0.0650 | 0.058* | |
C11 | 0.32669 (11) | 0.30623 (11) | 0.58756 (10) | 0.0200 (2) | |
H11A | 0.3878 | 0.3497 | 0.6814 | 0.024* | |
C12 | 0.21699 (10) | 0.40040 (11) | 0.59533 (10) | 0.0185 (2) | |
H12A | 0.1521 | 0.3562 | 0.5035 | 0.022* | |
C13 | 0.12302 (11) | 0.39830 (11) | 0.70980 (11) | 0.0227 (2) | |
H13A | 0.0511 | 0.4585 | 0.7138 | 0.027* | |
H13B | 0.1860 | 0.4440 | 0.8016 | 0.027* | |
C14 | 0.04220 (12) | 0.23922 (12) | 0.68246 (12) | 0.0263 (2) | |
H14A | −0.0144 | 0.2408 | 0.7603 | 0.032* | |
H14B | −0.0276 | 0.1967 | 0.5950 | 0.032* | |
C15 | 0.14871 (12) | 0.14127 (12) | 0.66941 (12) | 0.0270 (2) | |
H15A | 0.0932 | 0.0370 | 0.6436 | 0.032* | |
H15B | 0.2096 | 0.1758 | 0.7610 | 0.032* | |
C16 | 0.24777 (12) | 0.14630 (11) | 0.55875 (12) | 0.0263 (2) | |
H16A | 0.3208 | 0.0881 | 0.5580 | 0.032* | |
H16B | 0.1882 | 0.0995 | 0.4652 | 0.032* | |
N11 | 0.29472 (9) | 0.55411 (9) | 0.62213 (9) | 0.01932 (18) | |
H13 | 0.3728 | 0.5518 | 0.5722 | 0.023* | |
O11 | 0.42248 (8) | 0.31328 (8) | 0.48741 (8) | 0.02631 (18) | |
H11 | 0.3815 | 0.2520 | 0.4069 | 0.039* | |
C17 | 0.1977 (2) | 0.63305 (17) | 0.5819 (2) | 0.0227 (5) | 0.736 (2) |
H17A | 0.1068 | 0.6233 | 0.6250 | 0.027* | 0.736 (2) |
H17B | 0.1707 | 0.5871 | 0.4789 | 0.027* | 0.736 (2) |
C18 | 0.2728 (7) | 0.7966 (2) | 0.6294 (2) | 0.0268 (7) | 0.736 (2) |
H8C | 0.3696 | 0.8062 | 0.5963 | 0.032* | 0.736 (2) |
H8D | 0.2135 | 0.8439 | 0.5877 | 0.032* | 0.736 (2) |
O12 | 0.29099 (14) | 0.87110 (12) | 0.77732 (11) | 0.0360 (3) | 0.736 (2) |
H12 | 0.3499 | 0.9551 | 0.8028 | 0.054* | 0.736 (2) |
C27 | 0.1984 (5) | 0.6517 (6) | 0.6199 (6) | 0.0188 (13) | 0.264 (2) |
H27A | 0.1557 | 0.6820 | 0.7087 | 0.023* | 0.264 (2) |
H27B | 0.1168 | 0.5934 | 0.5426 | 0.023* | 0.264 (2) |
C28 | 0.273 (2) | 0.7909 (5) | 0.6017 (10) | 0.0309 (16) | 0.264 (2) |
H28A | 0.2036 | 0.8554 | 0.6128 | 0.037* | 0.264 (2) |
H28B | 0.3579 | 0.8474 | 0.6756 | 0.037* | 0.264 (2) |
O22 | 0.3202 (4) | 0.7557 (5) | 0.4685 (4) | 0.0497 (12) | 0.264 (2) |
H2D | 0.4005 | 0.7322 | 0.4701 | 0.075* | 0.264 (2) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0180 (4) | 0.0213 (5) | 0.0178 (5) | 0.0038 (4) | 0.0033 (4) | 0.0055 (4) |
C2 | 0.0211 (5) | 0.0222 (5) | 0.0179 (5) | 0.0023 (4) | 0.0022 (4) | 0.0049 (4) |
C3 | 0.0206 (5) | 0.0313 (6) | 0.0258 (5) | 0.0020 (4) | 0.0046 (4) | 0.0081 (5) |
C4 | 0.0200 (5) | 0.0375 (6) | 0.0273 (6) | 0.0076 (4) | 0.0015 (4) | 0.0074 (5) |
C5 | 0.0260 (5) | 0.0328 (6) | 0.0296 (6) | 0.0114 (4) | 0.0025 (4) | 0.0109 (5) |
C6 | 0.0238 (5) | 0.0267 (5) | 0.0245 (5) | 0.0061 (4) | 0.0029 (4) | 0.0108 (4) |
C7 | 0.0322 (6) | 0.0208 (5) | 0.0365 (6) | 0.0008 (4) | 0.0089 (5) | 0.0079 (5) |
C8 | 0.0432 (7) | 0.0230 (5) | 0.0389 (7) | 0.0092 (5) | 0.0181 (5) | 0.0118 (5) |
N1 | 0.0245 (4) | 0.0194 (4) | 0.0246 (5) | 0.0025 (3) | 0.0042 (3) | 0.0074 (3) |
O1 | 0.0175 (3) | 0.0282 (4) | 0.0217 (4) | 0.0049 (3) | 0.0027 (3) | 0.0072 (3) |
O2 | 0.0348 (5) | 0.0325 (5) | 0.0343 (5) | 0.0061 (4) | 0.0079 (4) | −0.0004 (4) |
C11 | 0.0200 (5) | 0.0195 (5) | 0.0197 (5) | 0.0058 (4) | 0.0055 (4) | 0.0064 (4) |
C12 | 0.0186 (4) | 0.0178 (4) | 0.0175 (5) | 0.0038 (3) | 0.0022 (4) | 0.0061 (4) |
C13 | 0.0228 (5) | 0.0224 (5) | 0.0240 (5) | 0.0078 (4) | 0.0086 (4) | 0.0090 (4) |
C14 | 0.0234 (5) | 0.0274 (5) | 0.0292 (6) | 0.0043 (4) | 0.0075 (4) | 0.0132 (5) |
C15 | 0.0307 (6) | 0.0213 (5) | 0.0303 (6) | 0.0050 (4) | 0.0083 (4) | 0.0122 (4) |
C16 | 0.0304 (5) | 0.0183 (5) | 0.0289 (6) | 0.0071 (4) | 0.0095 (4) | 0.0073 (4) |
N11 | 0.0184 (4) | 0.0172 (4) | 0.0229 (4) | 0.0050 (3) | 0.0037 (3) | 0.0083 (3) |
O11 | 0.0249 (4) | 0.0248 (4) | 0.0254 (4) | 0.0051 (3) | 0.0113 (3) | 0.0059 (3) |
C17 | 0.0265 (9) | 0.0195 (9) | 0.0187 (12) | 0.0056 (6) | −0.0048 (7) | 0.0049 (8) |
C18 | 0.0282 (13) | 0.0234 (11) | 0.0342 (13) | 0.0096 (9) | 0.0052 (14) | 0.0157 (8) |
O12 | 0.0447 (7) | 0.0240 (6) | 0.0315 (6) | 0.0064 (5) | 0.0058 (5) | 0.0041 (5) |
C27 | 0.020 (2) | 0.0218 (19) | 0.010 (2) | 0.0064 (14) | −0.0062 (14) | 0.0017 (15) |
C28 | 0.031 (4) | 0.032 (3) | 0.038 (3) | 0.011 (3) | 0.003 (3) | 0.022 (3) |
O22 | 0.043 (2) | 0.078 (3) | 0.055 (2) | 0.0238 (19) | 0.0152 (17) | 0.049 (2) |
C1—O1 | 1.4307 (12) | C12—N11 | 1.4716 (12) |
C1—C6 | 1.5194 (14) | C12—C13 | 1.5243 (14) |
C1—C2 | 1.5289 (13) | C12—H12A | 1.0000 |
C1—H1A | 1.0000 | C13—C14 | 1.5249 (14) |
C2—N1 | 1.4708 (13) | C13—H13A | 0.9900 |
C2—C3 | 1.5258 (14) | C13—H13B | 0.9900 |
C2—H2A | 1.0000 | C14—C15 | 1.5206 (16) |
C3—C4 | 1.5224 (16) | C14—H14A | 0.9900 |
C3—H3A | 0.9900 | C14—H14B | 0.9900 |
C3—H3B | 0.9900 | C15—C16 | 1.5279 (15) |
C4—C5 | 1.5239 (16) | C15—H15A | 0.9900 |
C4—H4A | 0.9900 | C15—H15B | 0.9900 |
C4—H4B | 0.9900 | C16—H16A | 0.9900 |
C5—C6 | 1.5276 (15) | C16—H16B | 0.9900 |
C5—H5A | 0.9900 | N11—C17 | 1.4733 (15) |
C5—H5B | 0.9900 | N11—C27 | 1.4736 (17) |
C6—H6A | 0.9900 | N11—H13 | 0.9200 |
C6—H6B | 0.9900 | O11—H11 | 0.8400 |
C7—N1 | 1.4681 (13) | C17—C18 | 1.5126 (15) |
C7—C8 | 1.5101 (14) | C17—H17A | 0.9900 |
C7—H7A | 0.9900 | C17—H17B | 0.9900 |
C7—H7B | 0.9900 | C18—O12 | 1.4161 (17) |
C8—O2 | 1.4152 (14) | C18—H8C | 0.9900 |
C8—H8A | 0.9900 | C18—H8D | 0.9900 |
C8—H8B | 0.9900 | O12—H12 | 0.8400 |
N1—H3 | 0.9200 | C27—C28 | 1.5117 (16) |
O1—H1 | 0.8400 | C27—H27A | 0.9900 |
O2—H2 | 0.8400 | C27—H27B | 0.9900 |
C11—O11 | 1.4253 (12) | C28—O22 | 1.4158 (17) |
C11—C16 | 1.5240 (14) | C28—H28A | 0.9900 |
C11—C12 | 1.5247 (13) | C28—H28B | 0.9900 |
C11—H11A | 1.0000 | O22—H2D | 0.8400 |
O1—C1—C6 | 109.13 (8) | N11—C12—C11 | 109.96 (8) |
O1—C1—C2 | 110.00 (8) | C13—C12—C11 | 109.62 (8) |
C6—C1—C2 | 111.32 (8) | N11—C12—H12A | 108.8 |
O1—C1—H1A | 108.8 | C13—C12—H12A | 108.8 |
C6—C1—H1A | 108.8 | C11—C12—H12A | 108.8 |
C2—C1—H1A | 108.8 | C12—C13—C14 | 111.16 (8) |
N1—C2—C3 | 112.09 (9) | C12—C13—H13A | 109.4 |
N1—C2—C1 | 108.79 (8) | C14—C13—H13A | 109.4 |
C3—C2—C1 | 110.17 (8) | C12—C13—H13B | 109.4 |
N1—C2—H2A | 108.6 | C14—C13—H13B | 109.4 |
C3—C2—H2A | 108.6 | H13A—C13—H13B | 108.0 |
C1—C2—H2A | 108.6 | C15—C14—C13 | 111.01 (9) |
C4—C3—C2 | 110.73 (9) | C15—C14—H14A | 109.4 |
C4—C3—H3A | 109.5 | C13—C14—H14A | 109.4 |
C2—C3—H3A | 109.5 | C15—C14—H14B | 109.4 |
C4—C3—H3B | 109.5 | C13—C14—H14B | 109.4 |
C2—C3—H3B | 109.5 | H14A—C14—H14B | 108.0 |
H3A—C3—H3B | 108.1 | C14—C15—C16 | 111.26 (9) |
C3—C4—C5 | 111.12 (9) | C14—C15—H15A | 109.4 |
C3—C4—H4A | 109.4 | C16—C15—H15A | 109.4 |
C5—C4—H4A | 109.4 | C14—C15—H15B | 109.4 |
C3—C4—H4B | 109.4 | C16—C15—H15B | 109.4 |
C5—C4—H4B | 109.4 | H15A—C15—H15B | 108.0 |
H4A—C4—H4B | 108.0 | C11—C16—C15 | 111.40 (8) |
C4—C5—C6 | 111.20 (9) | C11—C16—H16A | 109.3 |
C4—C5—H5A | 109.4 | C15—C16—H16A | 109.3 |
C6—C5—H5A | 109.4 | C11—C16—H16B | 109.3 |
C4—C5—H5B | 109.4 | C15—C16—H16B | 109.3 |
C6—C5—H5B | 109.4 | H16A—C16—H16B | 108.0 |
H5A—C5—H5B | 108.0 | C12—N11—C17 | 111.51 (10) |
C1—C6—C5 | 111.48 (9) | C12—N11—C27 | 114.4 (2) |
C1—C6—H6A | 109.3 | C12—N11—H13 | 109.3 |
C5—C6—H6A | 109.3 | C17—N11—H13 | 109.3 |
C1—C6—H6B | 109.3 | C27—N11—H13 | 118.9 |
C5—C6—H6B | 109.3 | C11—O11—H11 | 109.5 |
H6A—C6—H6B | 108.0 | N11—C17—C18 | 110.7 (3) |
N1—C7—C8 | 111.38 (9) | N11—C17—H17A | 109.5 |
N1—C7—H7A | 109.4 | C18—C17—H17A | 109.5 |
C8—C7—H7A | 109.4 | N11—C17—H17B | 109.5 |
N1—C7—H7B | 109.4 | C18—C17—H17B | 109.5 |
C8—C7—H7B | 109.4 | H17A—C17—H17B | 108.1 |
H7A—C7—H7B | 108.0 | O12—C18—C17 | 110.83 (13) |
O2—C8—C7 | 112.50 (9) | O12—C18—H8C | 109.5 |
O2—C8—H8A | 109.1 | C17—C18—H8C | 109.5 |
C7—C8—H8A | 109.1 | O12—C18—H8D | 109.5 |
O2—C8—H8B | 109.1 | C17—C18—H8D | 109.5 |
C7—C8—H8B | 109.1 | H8C—C18—H8D | 108.1 |
H8A—C8—H8B | 107.8 | N11—C27—C28 | 114.8 (9) |
C7—N1—C2 | 113.46 (8) | N11—C27—H27A | 108.6 |
C7—N1—H3 | 108.9 | C28—C27—H27A | 108.6 |
C2—N1—H3 | 108.9 | N11—C27—H27B | 108.6 |
C1—O1—H1 | 109.5 | C28—C27—H27B | 108.6 |
C8—O2—H2 | 109.5 | H27A—C27—H27B | 107.5 |
O11—C11—C16 | 112.33 (8) | O22—C28—C27 | 111.51 (17) |
O11—C11—C12 | 111.09 (8) | O22—C28—H28A | 109.3 |
C16—C11—C12 | 110.59 (8) | C27—C28—H28A | 109.3 |
O11—C11—H11A | 107.5 | O22—C28—H28B | 109.3 |
C16—C11—H11A | 107.5 | C27—C28—H28B | 109.3 |
C12—C11—H11A | 107.5 | H28A—C28—H28B | 108.0 |
N11—C12—C13 | 110.96 (8) | C28—O22—H2D | 109.5 |
O1—C1—C2—N1 | 58.98 (10) | C16—C11—C12—C13 | 58.18 (11) |
C6—C1—C2—N1 | −179.93 (8) | N11—C12—C13—C14 | 179.99 (8) |
O1—C1—C2—C3 | −177.78 (8) | C11—C12—C13—C14 | −58.38 (11) |
C6—C1—C2—C3 | −56.69 (11) | C12—C13—C14—C15 | 56.64 (12) |
N1—C2—C3—C4 | 178.85 (8) | C13—C14—C15—C16 | −54.18 (12) |
C1—C2—C3—C4 | 57.55 (11) | O11—C11—C16—C15 | 178.58 (9) |
C2—C3—C4—C5 | −57.19 (12) | C12—C11—C16—C15 | −56.69 (12) |
C3—C4—C5—C6 | 55.21 (12) | C14—C15—C16—C11 | 54.54 (12) |
O1—C1—C6—C5 | 176.79 (8) | C13—C12—N11—C17 | −78.63 (13) |
C2—C1—C6—C5 | 55.19 (12) | C11—C12—N11—C17 | 159.93 (12) |
C4—C5—C6—C1 | −54.22 (12) | C13—C12—N11—C27 | −63.4 (3) |
N1—C7—C8—O2 | −65.06 (13) | C11—C12—N11—C27 | 175.1 (2) |
C8—C7—N1—C2 | 165.35 (9) | C12—N11—C17—C18 | 171.76 (15) |
C3—C2—N1—C7 | 69.67 (11) | C27—N11—C17—C18 | 67.1 (10) |
C1—C2—N1—C7 | −168.25 (8) | N11—C17—C18—O12 | −68.9 (5) |
O11—C11—C12—N11 | −54.15 (10) | C12—N11—C27—C28 | −161.7 (5) |
C16—C11—C12—N11 | −179.58 (8) | C17—N11—C27—C28 | −80.4 (10) |
O11—C11—C12—C13 | −176.38 (8) | N11—C27—C28—O22 | 65.7 (16) |
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2···O1i | 0.84 | 1.89 | 2.7270 (11) | 172 |
N11—H13···O11ii | 0.92 | 2.37 | 3.1884 (11) | 148 |
O12—H12···O2ii | 0.84 | 1.90 | 2.7299 (14) | 170 |
O11—H11···N1 | 0.84 | 2.03 | 2.8379 (12) | 162 |
O1—H1···N11ii | 0.84 | 1.94 | 2.7701 (11) | 169 |
N1—H3···O12ii | 0.92 | 2.52 | 3.4051 (16) | 163 |
Symmetry codes: (i) −x+1, −y, −z; (ii) −x+1, −y+1, −z+1. |
Experimental details
Crystal data | |
Chemical formula | C8H17NO2 |
Mr | 159.23 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 173 |
a, b, c (Å) | 9.4334 (2), 10.0280 (3), 10.4651 (3) |
α, β, γ (°) | 112.954 (1), 92.429 (1), 102.055 (1) |
V (Å3) | 883.02 (4) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.48 × 0.40 × 0.15 |
Data collection | |
Diffractometer | Bruker SMART [APEXII?] CCD area-detector diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 20934, 4253, 3495 |
Rint | 0.046 |
(sin θ/λ)max (Å−1) | 0.661 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.037, 0.103, 1.03 |
No. of reflections | 4253 |
No. of parameters | 232 |
No. of restraints | 31 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.33, −0.19 |
Computer programs: SMART [APEX2?] (Bruker, 2005), SAINT [SAINT-Plus?] (Bruker, 2005), SHELXL97 (Sheldrick, 2008) and WinGX (Farrugia, 1997), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2···O1i | 0.84 | 1.89 | 2.7270 (11) | 172 |
N11—H13···O11ii | 0.92 | 2.37 | 3.1884 (11) | 148 |
O12—H12···O2ii | 0.84 | 1.90 | 2.7299 (14) | 170 |
O11—H11···N1 | 0.84 | 2.03 | 2.8379 (12) | 162 |
O1—H1···N11ii | 0.84 | 1.94 | 2.7701 (11) | 169 |
N1—H3···O12ii | 0.92 | 2.52 | 3.4051 (16) | 163 |
Symmetry codes: (i) −x+1, −y, −z; (ii) −x+1, −y+1, −z+1. |
Our investigation of reinforced β-amino alcohols as potential metal chelators has highlighted the need for a detailed understanding of the hydrogen-bonding topology associated with these compounds. The relationship between ligand backbone architecture and complex stability indicates that metal ions of smaller ionic radii are preferred upon grafting of cyclohexyl groups across donor atoms (de Sousa et al., 1991; de Sousa & Hancock, 1995). Short non-bonding hydrogen contacts have been reported to cause the observed dependency on metal ion radius (de Sousa et al., 1997a; Hancock et al., 1996), with complexes of larger metal ions being destabilized by hydrogen–hydrogen repulsions. The conformations of amino alcohol chelates and their respective inter- and intramolecular interactions in the solid state may contribute towards a better understanding of this observation. Solid-state analysis of a cycloalkyl-reinforced amino alcohol in which all donor atoms are linked via cyclohexyl bridges suggests that stronger intramolecular hydrogen bonding within the chelating cavity is accompanied by weakening of H···H repulsions (de Sousa & Fernandes, 2003; de Sousa et al., 1997b). The presence of intramolecular hydrogen bonds (Varadwaj et al., 2009), typically defined by string motifs S(n), is implied as relevant in rationalizing the observed trends in the relative stabilities of amino alcohol metal ion complexes. Recent studies of hydrogen-bonding arrays prevalent in a series of N-alkyldiethanolamine ligands relate intramolecular interactions to the steric constraints imposed by ligand backbone architectures (Churakov et al., 2009). Ligand backbone alterations include C-alkyl substitution of hydroxyethyl pendents and varied substituents on the amine N donor atom.
We report here a solid-state study of a reinforced diethanolamine derivative, (I), comprising a cyclohexyl bridge between the amine N atom and a single hydroxy O donor atom, representing C-alkyl substitution across an hydroxyethyl bridge in diethanolamine. Based on a previous study of N,N'-bis(2-hydroxycyclohexyl)-trans-cyclohexane-1,2-diamine (de Sousa & Fernandes, 2003), a crystal structure of (I) containing enantiomeric layers might be expected. In fact, both syn and anti conformations of (I) (Fig. 1), the latter disordered, occur in the structure, with alternating anti- and syn-enantiomeric double layers. The syn O1—C1—C2—N1 torsion angle of 58.99 (10)° suggests minimal torsional strain for the hydroxycyclohexyl pendent, accommodating a N1—C7—C8—O2 torsion angle of -65.11 (13)° for a gauche orientation of the hydroxyethyl pendent. In the anti conformer, the corresponding O1A—C1A—C2A—N1A torsion angle of -54.21 (10)° deviates from that of minimal strain for a cyclohexyl bridge [Reference?]. In addition, a distorted gauche hydroxyethyl pendent has torsion angle N1A—C7A—C8A—O2A = -68.9 (5)°. The hydroxyethyl groups of the predominantly anti conformers are disordered over two positions (Fig. 1), corresponding to anti and syn conformations [N11—C27—C28—O22 65.6 (16)°], with site occupancies of 0.736 (2) and 0.264 (2), respectively.
Pairs of syn enantiomers related by the inversion centre at (1/2, 0, 0) generate an R22(16) dimer (Bernstein et al., 1995) via strong O—H···O hydrogen bonds (Table 1, Fig. 2a), while anti enantiomeric pairs related by the inversion centre at (1/2, 1/2, 1/2) generate an R22(10) dimer via N—H···O hydrogen bonds (Table 1, Fig. 2b). Molecular planes, separated by 3.2 Å, of syn molecule pairs reveal significant puckering in the centrosymmetric 16-membered rings, compared with 0.72 Å in the structure of diethanolamine (Mootz et al., 1989).
Puckering of the R22(10) dimers is minimal, as evidenced by the molecular plane separation of 0.91 Å for pairs of anti molecules. The inversion centres of the R22(10) and R22(16) dimers are separated by 5.66 Å. Alternating R22(16) dimers are therefore significantly separated (11.32 Å) compared with their counterparts in the diethanolamine structure (4.46 Å), largely as a consequence of enantiomeric crystallization into separate layers. The tubular stacks observed in the structure of diethanolamine result from R22(16) dimers weakly linked via N—H···O hydrogen bonds.
Hydrogen bonding in (I) links R22(16) and R22(10) dimers, predominantly via O—H···O and O—H···N hydrogen bonds, to generate a tubular column extending in the [011] direction (Table 1, Fig. 3). Hydroxyethyl atom O12 acts as a hydrogen donor via atom H2 to hydroxyethyl atom O2ii (see Table 1 for details and symmetry codes) in an O—H···O interaction between anti and syn molecules of R22(10) and R22(16) dimers centred at (1/2, 1/2, 1/2) and (1/2, 1, 1), respectively. A symmetrically equivalent hydrogen bond involving atoms O12ii and O2 links R22(10) and R22(16) dimers centred at (1/2, 1/2, 1/2) and (1/2, 0, 0), respectively. These O12—H12···O2ii hydrogen bonds are stereospecific, occuring only between molecules of like chirality.
O—H···N hydrogen bonds between centrosymmetric dimers are restricted to the N and O atoms connected via the cyclohexyl bridge (Fig. 3). Stereospecificity originates from the conformation of the O donor atom. O11—H11···N1 hydrogen bonds occur only between syn and anti molecules of opposite chirality where the donor atom, O11, originates from an anti conformer. Hydroxycyclohexyl atom O11 of an anti (R,R) molecule acts as a donor via atom H11 to amine atom N1 of a syn (S,S) molecule (see Fig. 1), linking R22(10) and R22(16) dimers centred at (1/2, 1/2, 1/2) and (1/2, 0, 0), respectively. An equivalent interaction, between atom O11 of an anti (S,S) molecule and atom N1 of a syn (R,R) molecule, both at (1 - x, 1 - y, 1 - z), links R22(10) and R22(16) dimers centred at (1/2, 1/2, 1/2) and (1/2, 1, 1), respectively. O1—H1···N11ii hydrogen bonds occur between syn and anti molecules of like chirality, where donor atom O1 originates from a syn conformer. The R22(16) dimer centred at (1/2, 0, 0) is linked to the R22(10) dimer centred at (1/2, 1/2, 1/2) via atom O1 of a syn (S,S) molecule, hydrogen-bonded to N11ii of an anti (S,S) molecule. The R22(16) dimer centred at (1/2, 1, 1) is linked to the R22(10) dimer centred at (1/2, 1/2, 1/2) through an equivalent interaction between a syn (R,R) and anti (R,R) molecule. The intricate hydrogen-bonding array within the tubular columns is completed by very weak N—H···O interactions (Fig. 3). In the N1—H3···O12ii hydrogen bonds, donor atom N1 of a syn molecule is hydrogen-bonded to hydroxyethyl atom O12ii of an anti molecule with like chirality.
In conclusion, the anti conformation of (I), observed when grafting a cyclohexyl bridge across a hydroxylethyl pendent, facilitates stronger O—H···O hydrogen bonds between centrosymmetric dimers and favours the formation of tubular columns. Grafting of cyclohexyl bridges into the carbon backbone of amino alcohols may prove to be a useful synthetic strategy in designing self-assembled supramolecular structures of β-amino alcohols.