Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270112037195/dt3014sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270112037195/dt3014Isup2.hkl | |
Chemical Markup Language (CML) file https://doi.org/10.1107/S0108270112037195/dt3014Isup3.cml |
CCDC reference: 906571
For related literature, see: Arunan et al. (2011); Bernstein et al. (1995); Carrillo et al. (2012); Clay et al. (1979); Custelcean et al. (2002); Gunnlaugsson, Brougham, Fanning, Nieuwenhuyzen, O'Brien & Viguier (2004); Gunnlaugsson, Leonard, Mulready & Nieuwenhuyzen (2004); Howard et al. (1998); Iitaka et al. (1974); Kemp & Vellacio (1980); Khasnis et al. (1992); Niu et al. (2002, 2004); Pal et al. (2003); Rousselin et al. (2010); Sousa et al. (1991, 1997, 2010a, 2010b); Tzeng et al. (2006); Warden et al. (2004); Widlicka et al. (2002); Wood et al. (2009).
Chemicals were used as obtained from suppliers: cyclen from Strem Chemicals, and cyclohexene oxide, ethanol and ethyl acetate from Aldrich. The target compound, (I), was synthesized as reported previously (de Sousa et al., 1997). Cyclen (2.3 g, 13.4 mmol) was dissolved in anhydrous ethanol (100 ml) with continuous stirring. Cyclohexene oxide (1.1 g, 11.2 mmol) was added to the solution, which was then refluxed for 48 h under a CaCl2 drying tube. The solvent was removed under reduced pressure to afford a white amorphous solid. Recrystallization from hot ethyl acetate afforded the monosubstituted product, (I), which was characterized by NMR and ESI–MS (yield 37%). Spectroscopic analysis: 1H NMR (D2O, 300 MHz, δ, p.p.m.): 3.53–3.47 (1H, m, CH), 2.82–2.67 (10H, m, CH2), 2.59–2.49 (6H, m, CH2), 2.38–2.34 (1H, m, CH), 2.01–1.99 (1H, m, CH2), 1.87–1.84 (1H, m, CH2), 1.72–1.66 (2H, m, CH2), 1.28–1.17 (4H, m, CH2); 13C NMR (D2O, 300 MHz, δ, p.p.m.): 70.26, 64.84, 47.27, 45.48, 44.32, 33.77, 24.92, 24.06, 23.35; ESI, m/z: 277 (M + H, 100%), 293 (M + Na, 10%).
H atoms were first located in a 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,N,O). H atoms involved in hydrogen bonding were refined freely.
Data collection: SMART-NT (Bruker, 1998); cell refinement: SMART-NT (Bruker, 1998); data reduction: SAINT-Plus (Bruker, 1999); 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).
C14H30N4O | Dx = 1.182 Mg m−3 |
Mr = 270.42 | Melting point: 418 K |
Orthorhombic, Pbca | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ac 2ab | Cell parameters from 858 reflections |
a = 10.6137 (14) Å | θ = 2.4–21.0° |
b = 8.3339 (10) Å | µ = 0.08 mm−1 |
c = 34.350 (4) Å | T = 173 K |
V = 3038.4 (6) Å3 | Rhombus, white |
Z = 8 | 0.50 × 0.39 × 0.24 mm |
F(000) = 1200 |
Bruker SMART CCD area-detector diffractometer | 1813 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.055 |
Graphite monochromator | θmax = 26.4°, θmin = 1.2° |
ϕ and ω scans | h = −13→8 |
17310 measured reflections | k = −10→10 |
3127 independent reflections | l = −39→42 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.045 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.106 | w = 1/[σ2(Fo2) + (0.0562P)2] where P = (Fo2 + 2Fc2)/3 |
S = 0.87 | (Δ/σ)max = 0.001 |
3127 reflections | Δρmax = 0.26 e Å−3 |
189 parameters | Δρmin = −0.22 e Å−3 |
0 restraints | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc* = kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0509 (19) |
C14H30N4O | V = 3038.4 (6) Å3 |
Mr = 270.42 | Z = 8 |
Orthorhombic, Pbca | Mo Kα radiation |
a = 10.6137 (14) Å | µ = 0.08 mm−1 |
b = 8.3339 (10) Å | T = 173 K |
c = 34.350 (4) Å | 0.50 × 0.39 × 0.24 mm |
Bruker SMART CCD area-detector diffractometer | 1813 reflections with I > 2σ(I) |
17310 measured reflections | Rint = 0.055 |
3127 independent reflections |
R[F2 > 2σ(F2)] = 0.045 | 0 restraints |
wR(F2) = 0.106 | H atoms treated by a mixture of independent and constrained refinement |
S = 0.87 | Δρmax = 0.26 e Å−3 |
3127 reflections | Δρmin = −0.22 e Å−3 |
189 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
C1 | 0.00867 (16) | 0.02721 (19) | 0.67222 (5) | 0.0234 (4) | |
H1 | 0.0172 | 0.1146 | 0.6920 | 0.028* | |
C2 | 0.14020 (16) | −0.0404 (2) | 0.66637 (5) | 0.0246 (4) | |
H2 | 0.1368 | −0.1298 | 0.6470 | 0.030* | |
C3 | 0.19131 (17) | −0.1042 (2) | 0.70498 (5) | 0.0285 (5) | |
H3A | 0.2748 | −0.1538 | 0.7005 | 0.034* | |
H3B | 0.2029 | −0.0134 | 0.7232 | 0.034* | |
C4 | 0.10421 (18) | −0.2274 (2) | 0.72344 (5) | 0.0341 (5) | |
H4A | 0.1007 | −0.3241 | 0.7067 | 0.041* | |
H4B | 0.1384 | −0.2596 | 0.7491 | 0.041* | |
C5 | −0.02698 (19) | −0.1613 (2) | 0.72866 (5) | 0.0357 (5) | |
H5A | −0.0252 | −0.0733 | 0.7480 | 0.043* | |
H5B | −0.0830 | −0.2468 | 0.7387 | 0.043* | |
C6 | −0.07878 (17) | −0.0983 (2) | 0.69027 (5) | 0.0285 (5) | |
H6A | −0.1627 | −0.0499 | 0.6948 | 0.034* | |
H6B | −0.0893 | −0.1888 | 0.6719 | 0.034* | |
C7 | −0.09207 (18) | −0.0073 (2) | 0.60778 (5) | 0.0281 (5) | |
H7A | −0.1793 | −0.0357 | 0.6153 | 0.034* | |
H7B | −0.0415 | −0.1072 | 0.6078 | 0.034* | |
C8 | −0.09285 (18) | 0.0628 (2) | 0.56712 (5) | 0.0316 (5) | |
H8A | −0.1279 | −0.0170 | 0.5487 | 0.038* | |
H8B | −0.1479 | 0.1587 | 0.5666 | 0.038* | |
C9 | 0.03388 (19) | 0.2218 (2) | 0.52238 (5) | 0.0342 (5) | |
H9A | −0.0355 | 0.2999 | 0.5259 | 0.041* | |
H9B | 0.0190 | 0.1636 | 0.4977 | 0.041* | |
C10 | 0.1574 (2) | 0.3106 (2) | 0.51990 (5) | 0.0393 (5) | |
H10A | 0.2252 | 0.2336 | 0.5133 | 0.047* | |
H10B | 0.1526 | 0.3908 | 0.4987 | 0.047* | |
C11 | 0.11367 (19) | 0.5332 (2) | 0.56571 (5) | 0.0354 (5) | |
H11A | 0.0790 | 0.5785 | 0.5413 | 0.043* | |
H11B | 0.1688 | 0.6156 | 0.5776 | 0.043* | |
C12 | 0.00581 (18) | 0.4975 (2) | 0.59335 (5) | 0.0300 (5) | |
H12A | −0.0422 | 0.5971 | 0.5985 | 0.036* | |
H12B | −0.0520 | 0.4189 | 0.5812 | 0.036* | |
C13 | −0.04617 (18) | 0.3868 (2) | 0.65762 (5) | 0.0275 (4) | |
H13A | −0.1046 | 0.4786 | 0.6606 | 0.033* | |
H13B | −0.0074 | 0.3661 | 0.6833 | 0.033* | |
C14 | −0.12261 (17) | 0.2389 (2) | 0.64570 (5) | 0.0268 (4) | |
H14A | −0.1802 | 0.2087 | 0.6671 | 0.032* | |
H14B | −0.1744 | 0.2649 | 0.6226 | 0.032* | |
N1 | −0.03994 (13) | 0.10406 (15) | 0.63674 (4) | 0.0216 (4) | |
N2 | 0.03323 (16) | 0.10749 (19) | 0.55476 (5) | 0.0309 (4) | |
N3 | 0.18955 (17) | 0.3920 (2) | 0.55627 (4) | 0.0349 (4) | |
N4 | 0.05355 (14) | 0.43253 (18) | 0.63025 (4) | 0.0257 (4) | |
O1 | 0.21727 (13) | 0.08585 (14) | 0.65153 (4) | 0.0289 (3) | |
H2N | 0.0699 (16) | 0.154 (2) | 0.5723 (5) | 0.024 (6)* | |
H3N | 0.272 (2) | 0.422 (2) | 0.5536 (6) | 0.054 (7)* | |
H4N | 0.0993 (16) | 0.347 (2) | 0.6241 (5) | 0.028 (5)* | |
H110 | 0.292 (2) | 0.045 (2) | 0.6439 (6) | 0.052 (7)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0232 (10) | 0.0223 (9) | 0.0246 (9) | 0.0002 (8) | 0.0010 (8) | 0.0018 (8) |
C2 | 0.0248 (10) | 0.0220 (9) | 0.0271 (10) | −0.0016 (8) | 0.0026 (8) | 0.0018 (8) |
C3 | 0.0271 (11) | 0.0295 (10) | 0.0288 (10) | 0.0037 (9) | −0.0017 (8) | 0.0039 (9) |
C4 | 0.0390 (13) | 0.0333 (11) | 0.0299 (11) | 0.0048 (10) | 0.0023 (9) | 0.0096 (9) |
C5 | 0.0392 (13) | 0.0337 (11) | 0.0344 (11) | −0.0001 (10) | 0.0091 (9) | 0.0089 (9) |
C6 | 0.0251 (11) | 0.0286 (10) | 0.0318 (10) | −0.0019 (9) | 0.0042 (8) | 0.0058 (9) |
C7 | 0.0298 (11) | 0.0247 (9) | 0.0299 (11) | −0.0052 (9) | −0.0030 (8) | 0.0007 (8) |
C8 | 0.0341 (11) | 0.0306 (10) | 0.0302 (10) | −0.0037 (9) | −0.0069 (9) | −0.0021 (9) |
C9 | 0.0444 (13) | 0.0369 (11) | 0.0213 (10) | 0.0030 (10) | −0.0030 (9) | 0.0019 (9) |
C10 | 0.0448 (13) | 0.0467 (12) | 0.0265 (11) | 0.0028 (11) | 0.0024 (9) | 0.0107 (10) |
C11 | 0.0413 (13) | 0.0316 (11) | 0.0335 (11) | −0.0057 (10) | −0.0066 (9) | 0.0127 (9) |
C12 | 0.0348 (12) | 0.0218 (9) | 0.0333 (11) | 0.0013 (9) | −0.0082 (9) | 0.0054 (8) |
C13 | 0.0307 (11) | 0.0219 (9) | 0.0298 (10) | 0.0033 (9) | 0.0005 (8) | −0.0009 (8) |
C14 | 0.0231 (10) | 0.0264 (10) | 0.0309 (10) | 0.0017 (9) | 0.0007 (8) | 0.0010 (8) |
N1 | 0.0221 (8) | 0.0201 (7) | 0.0227 (8) | 0.0014 (7) | −0.0028 (6) | 0.0006 (6) |
N2 | 0.0377 (10) | 0.0315 (9) | 0.0235 (9) | −0.0014 (8) | −0.0028 (8) | 0.0010 (8) |
N3 | 0.0311 (10) | 0.0407 (10) | 0.0329 (10) | −0.0030 (9) | −0.0023 (8) | 0.0096 (8) |
N4 | 0.0289 (9) | 0.0209 (8) | 0.0272 (9) | 0.0018 (8) | −0.0024 (7) | 0.0033 (7) |
O1 | 0.0233 (8) | 0.0256 (7) | 0.0378 (8) | −0.0005 (6) | 0.0062 (6) | 0.0081 (6) |
C1—N1 | 1.470 (2) | C9—N2 | 1.465 (2) |
C1—C2 | 1.519 (2) | C9—C10 | 1.508 (3) |
C1—C6 | 1.530 (2) | C9—H9A | 0.9900 |
C1—H1 | 1.0000 | C9—H9B | 0.9900 |
C2—O1 | 1.427 (2) | C10—N3 | 1.462 (2) |
C2—C3 | 1.528 (2) | C10—H10A | 0.9900 |
C2—H2 | 1.0000 | C10—H10B | 0.9900 |
C3—C4 | 1.520 (2) | C11—N3 | 1.462 (2) |
C3—H3A | 0.9900 | C11—C12 | 1.517 (3) |
C3—H3B | 0.9900 | C11—H11A | 0.9900 |
C4—C5 | 1.508 (3) | C11—H11B | 0.9900 |
C4—H4A | 0.9900 | C12—N4 | 1.468 (2) |
C4—H4B | 0.9900 | C12—H12A | 0.9900 |
C5—C6 | 1.522 (2) | C12—H12B | 0.9900 |
C5—H5A | 0.9900 | C13—N4 | 1.466 (2) |
C5—H5B | 0.9900 | C13—C14 | 1.531 (2) |
C6—H6A | 0.9900 | C13—H13A | 0.9900 |
C6—H6B | 0.9900 | C13—H13B | 0.9900 |
C7—N1 | 1.469 (2) | C14—N1 | 1.459 (2) |
C7—C8 | 1.514 (2) | C14—H14A | 0.9900 |
C7—H7A | 0.9900 | C14—H14B | 0.9900 |
C7—H7B | 0.9900 | N2—H2N | 0.814 (17) |
C8—N2 | 1.452 (2) | N3—H3N | 0.92 (2) |
C8—H8A | 0.9900 | N4—H4N | 0.886 (18) |
C8—H8B | 0.9900 | O1—H110 | 0.90 (2) |
N1—C1—C2 | 112.00 (13) | N2—C9—H9A | 109.3 |
N1—C1—C6 | 114.89 (14) | C10—C9—H9A | 109.3 |
C2—C1—C6 | 110.95 (13) | N2—C9—H9B | 109.3 |
N1—C1—H1 | 106.1 | C10—C9—H9B | 109.3 |
C2—C1—H1 | 106.1 | H9A—C9—H9B | 108.0 |
C6—C1—H1 | 106.1 | N3—C10—C9 | 112.48 (16) |
O1—C2—C1 | 107.47 (13) | N3—C10—H10A | 109.1 |
O1—C2—C3 | 111.29 (14) | C9—C10—H10A | 109.1 |
C1—C2—C3 | 109.91 (14) | N3—C10—H10B | 109.1 |
O1—C2—H2 | 109.4 | C9—C10—H10B | 109.1 |
C1—C2—H2 | 109.4 | H10A—C10—H10B | 107.8 |
C3—C2—H2 | 109.4 | N3—C11—C12 | 113.35 (15) |
C4—C3—C2 | 112.39 (15) | N3—C11—H11A | 108.9 |
C4—C3—H3A | 109.1 | C12—C11—H11A | 108.9 |
C2—C3—H3A | 109.1 | N3—C11—H11B | 108.9 |
C4—C3—H3B | 109.1 | C12—C11—H11B | 108.9 |
C2—C3—H3B | 109.1 | H11A—C11—H11B | 107.7 |
H3A—C3—H3B | 107.9 | N4—C12—C11 | 110.63 (15) |
C5—C4—C3 | 111.37 (15) | N4—C12—H12A | 109.5 |
C5—C4—H4A | 109.4 | C11—C12—H12A | 109.5 |
C3—C4—H4A | 109.4 | N4—C12—H12B | 109.5 |
C5—C4—H4B | 109.4 | C11—C12—H12B | 109.5 |
C3—C4—H4B | 109.4 | H12A—C12—H12B | 108.1 |
H4A—C4—H4B | 108.0 | N4—C13—C14 | 114.85 (14) |
C4—C5—C6 | 110.88 (15) | N4—C13—H13A | 108.6 |
C4—C5—H5A | 109.5 | C14—C13—H13A | 108.6 |
C6—C5—H5A | 109.5 | N4—C13—H13B | 108.6 |
C4—C5—H5B | 109.5 | C14—C13—H13B | 108.6 |
C6—C5—H5B | 109.5 | H13A—C13—H13B | 107.5 |
H5A—C5—H5B | 108.1 | N1—C14—C13 | 110.97 (14) |
C5—C6—C1 | 111.59 (15) | N1—C14—H14A | 109.4 |
C5—C6—H6A | 109.3 | C13—C14—H14A | 109.4 |
C1—C6—H6A | 109.3 | N1—C14—H14B | 109.4 |
C5—C6—H6B | 109.3 | C13—C14—H14B | 109.4 |
C1—C6—H6B | 109.3 | H14A—C14—H14B | 108.0 |
H6A—C6—H6B | 108.0 | C14—N1—C7 | 113.78 (13) |
N1—C7—C8 | 112.51 (14) | C14—N1—C1 | 111.83 (13) |
N1—C7—H7A | 109.1 | C7—N1—C1 | 114.73 (13) |
C8—C7—H7A | 109.1 | C8—N2—C9 | 113.15 (15) |
N1—C7—H7B | 109.1 | C8—N2—H2N | 110.3 (12) |
C8—C7—H7B | 109.1 | C9—N2—H2N | 104.5 (12) |
H7A—C7—H7B | 107.8 | C10—N3—C11 | 115.78 (16) |
N2—C8—C7 | 111.32 (15) | C10—N3—H3N | 105.3 (13) |
N2—C8—H8A | 109.4 | C11—N3—H3N | 109.2 (13) |
C7—C8—H8A | 109.4 | C13—N4—C12 | 113.59 (14) |
N2—C8—H8B | 109.4 | C13—N4—H4N | 109.9 (11) |
C7—C8—H8B | 109.4 | C12—N4—H4N | 106.3 (11) |
H8A—C8—H8B | 108.0 | C2—O1—H110 | 109.5 (13) |
N2—C9—C10 | 111.47 (16) | ||
N1—C1—C2—O1 | 53.28 (18) | C13—C14—N1—C7 | −150.68 (14) |
C6—C1—C2—O1 | −176.87 (13) | C13—C14—N1—C1 | 77.34 (17) |
N1—C1—C2—C3 | 174.53 (13) | C8—C7—N1—C14 | 72.06 (19) |
C6—C1—C2—C3 | −55.62 (19) | C8—C7—N1—C1 | −157.38 (15) |
O1—C2—C3—C4 | 174.39 (14) | C2—C1—N1—C14 | −147.69 (14) |
C1—C2—C3—C4 | 55.45 (19) | C6—C1—N1—C14 | 84.53 (17) |
C2—C3—C4—C5 | −55.3 (2) | C2—C1—N1—C7 | 80.80 (17) |
C3—C4—C5—C6 | 54.6 (2) | C6—C1—N1—C7 | −47.0 (2) |
C4—C5—C6—C1 | −55.7 (2) | C7—C8—N2—C9 | −160.77 (15) |
N1—C1—C6—C5 | −175.01 (14) | C10—C9—N2—C8 | 159.14 (16) |
C2—C1—C6—C5 | 56.68 (19) | C9—C10—N3—C11 | −71.6 (2) |
N1—C7—C8—N2 | 58.4 (2) | C12—C11—N3—C10 | 96.61 (19) |
N2—C9—C10—N3 | −55.6 (2) | C14—C13—N4—C12 | 69.94 (19) |
N3—C11—C12—N4 | 59.6 (2) | C11—C12—N4—C13 | −176.81 (14) |
N4—C13—C14—N1 | 52.2 (2) |
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H2N···N1 | 0.814 (17) | 2.537 (17) | 2.921 (2) | 110.3 (14) |
N2—H2N···N3 | 0.814 (17) | 2.419 (17) | 2.895 (2) | 118.2 (14) |
N3—H3N···N2i | 0.92 (2) | 2.58 (2) | 3.447 (2) | 158.2 (17) |
N4—H4N···N1 | 0.888 (17) | 2.544 (17) | 2.920 (2) | 106.3 (13) |
N4—H4N···N3 | 0.888 (17) | 2.547 (17) | 2.942 (2) | 107.8 (13) |
O1—H110···N4ii | 0.90 (2) | 1.95 (2) | 2.843 (2) | 172.7 (19) |
Symmetry codes: (i) −x+1/2, y+1/2, z; (ii) −x+1/2, y−1/2, z. |
Experimental details
Crystal data | |
Chemical formula | C14H30N4O |
Mr | 270.42 |
Crystal system, space group | Orthorhombic, Pbca |
Temperature (K) | 173 |
a, b, c (Å) | 10.6137 (14), 8.3339 (10), 34.350 (4) |
V (Å3) | 3038.4 (6) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 0.08 |
Crystal size (mm) | 0.50 × 0.39 × 0.24 |
Data collection | |
Diffractometer | Bruker SMART CCD area-detector diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 17310, 3127, 1813 |
Rint | 0.055 |
(sin θ/λ)max (Å−1) | 0.626 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.045, 0.106, 0.87 |
No. of reflections | 3127 |
No. of parameters | 189 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.26, −0.22 |
Computer programs: SMART-NT (Bruker, 1998), SAINT-Plus (Bruker, 1999), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H2N···N1 | 0.814 (17) | 2.537 (17) | 2.921 (2) | 110.3 (14) |
N2—H2N···N3 | 0.814 (17) | 2.419 (17) | 2.895 (2) | 118.2 (14) |
N3—H3N···N2i | 0.92 (2) | 2.58 (2) | 3.447 (2) | 158.2 (17) |
N4—H4N···N1 | 0.888 (17) | 2.544 (17) | 2.920 (2) | 106.3 (13) |
N4—H4N···N3 | 0.888 (17) | 2.547 (17) | 2.942 (2) | 107.8 (13) |
O1—H110···N4ii | 0.90 (2) | 1.95 (2) | 2.843 (2) | 172.7 (19) |
Symmetry codes: (i) −x+1/2, y+1/2, z; (ii) −x+1/2, y−1/2, z. |
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The controlled design of tubular structures is desirable for the synthesis of self-assembled organic nanotubes. A recent strategy for attaining self-assembled tubular structures exploits noncovalent interactions indigenous to macrocyclic structures (Carrillo et al., 2012). Flat conformations adopted by macrocyclic structures enhance the congruency of donor–acceptor interactions, rendering them particularly useful solid-state synthons for the design of self-assembled nanotubes. We have recently identified 2-[(2-hydroxyethyl)amino]cyclohexanol (CyEA) as a suitable solid-state synthon for the rational design of tubular structures (de Sousa et al., 2010a,b). For this synthon, donor–acceptor complementarity is dependent upon molecular conformation, where O—H···O and N—H···O hydrogen-bonding interactions favour the formation of hydrogen-bonded ring Rda(n) motifs [see Bernstein et al. (1995) for definitions of hydrogen-bonding motifs]. Stereogenic centres inherent in hydroxycyclohexyl pendent groups influence the stereospecificity of these interactions.
Solid-state structures indicate that hydrogen bonding between R,R- and S,S-CyEA enantiomers is best described by alternating dimeric ring motifs in tubular columns incorporating hydrophilic inner cores. Linking of CyEA synthons via N-alkylation segments the inner core, which is an undesirable effect of bridging alkyl chains. We propose that the formation of parallel hydrogen-bonded ring motifs, akin to the introduction of parallel macrocyclic rings (Carrillo et al., 2012), remedies the discontinuity of the hydrophilic inner core. The solid-state structure of cyclen (Pal et al., 2003) shows that macrocyclic N atoms occupy the vertices of a square in a [3.3.3.3] conformation with symmetrically related (λλλλ)/(δδδδ) helicities. Helicity in cyclen-based compounds is highly variable and in solution concerted ring inversion, λλλλ → δδδδ (Howard et al., 1998), interconverts diastereomers of cyclen-based lanthanide complexes. Cyclen ring helicities are dependent upon: (i) the steric demand of the N-alkyl substituents (Tzeng et al., 2006; Gunnlaugsson, Leonard et al., 2004; Gunnlaugsson, Brougham et al., 2004); (ii) the bridging of the macrocyclic framework (Niu et al., 2002, 2004); (iii) C-alkylation of the macrocyclic backbone (Widlicka et al., 2002); and (iv) protonation of macrocyclic amine N atoms (Warden et al., 2004).
Solid-state data also show that changes in the cyclen helicity accompany the encapsulation of metal ions by cyclen-based ligands (Custelcean et al., 2002; Gunnlaugsson, Brougham et al., 2004; Niu et al., 2004; Iitaka et al., 1974; Gunnlaugsson, Leonard et al., 2004). In this study, we report the solid-state structure of the title compound, (I), cycyclen, which may be viewed as a derivative of CyEA in which the ethanolamine fragment is replaced by the tetraaza macrocycle 1,4,7,10-tetraazacyclododecane (cyclen).
The pendent hydroxycyclohexyl group of (I) adopts an endo orientation relative to the macrocyclic cavity (Fig. 1). The N1—C1—C2—O1 torsion angle of 53.28 (18)° deviates from the minimum-strain value for a cyclohexyl bridge (de Sousa et al., 1991; Kemp & Vellacio, 1980), accommodating a distorted macrocyclic [3.3.3.3] square conformation. A similar deviation in the hydroxycyclohexyl torsion angle has previously been noted for the anti CyEA conformer (de Sousa et al., 2010a), in which the hydroxycyclohexyl O atoms act as hydrogen-bond donors in tubular structures, promoted by O—H···O hydrogen bonds.
A stereospecific intermolecular O—H···N interaction, in which hydroxyalkyl atom O1 acts as a hydrogen-bond donor via atom H110 to macrocyclic amine atom N4ii (see Table 1 for details and symmetry codes), occurs only between molecules of (I) of opposite chirality (Fig. 2). Hydroxycyclohexyl atom O1 of an S,S molecule at (x, y, z), acts as a hydrogen-bond donor to amine atom N4ii at (-x + 1/2, y - 1/2, z) of an R,R molecule, defining a unitary level C8 motif. A cyclen distorted [3.3.3.3] square conformation is observed in the structure of cycyclen, with (λδλλ) ring helicity and an N2—C9—C10—N3 torsion angle of -55.6 (2)°. The average N—C—C—N torsion angle (56.44°) deviates substantially from the cyclen value (62.27°; Pal et al., 2003) and resembles that of the Cu complexes [Cu(R,R-cycyclen)]2+ (51.13°; de Sousa et al., 1997) and [Cu(cyclen)NO3]+ (52.92°; Clay et al., 1979), both exhibiting (λλλλ) cyclen helicity in the solid state.
Weak bifurcated N2—H2N···N1, N2—H2N···N3, N4—H4N···N1 and N4—H4N···N3 (see Table 1 and Fig. 1) intramolecular interactions within the macrocyclic cavity, as indicated by their N—H···N angles (Arunan et al., 2011; Wood et al., 2009), are unlikely to impose macrocyclic helicity or conformation. Although uncommon, intermolecular N—H···N hydrogen-bonding interactions between cyclen N atoms have been observed for (λλδδ) (Khasnis et al., 1992) and (δδλλ) (Rousselin et al., 2010) helicities. The (λδλλ) cyclen ring helicity of cycyclen includes a stereospecific N3—H3N···N2 interaction, whicg occurs only between molecules of opposite chirality (Fig. 2). Amine atom N3 of the S,S molecule at (x, y, z), a hydrogen-bond acceptor in the intramolecular macrocyclic N2—H2N···N3 interaction, additionally acts as a hydrogen-bond donor to atom N2i of the R,R molecule at (-x + 1/2, y + 1/2, z), describing a unitary level C5 motif.
O1—H110···N4 and N2—H2N···N3 interactions link cycyclen enantiomers in a head-to-tail manner, defining C22(19)R22(13) motifs at the binary level. The stereospecificity of these hydrogen bonds is propogated by a b-glide plane, perpendicular to (100), to form a helical channel along [010] (Fig. 3). The molecular conformations of the hydrogen-bonded hydroxycyclohexyl and macrocyclic ethylenediamine backbones in cycyclen with R22(13) motifs resemble the conformations of the R22(16) motifs in enantiomeric syn CyEA dimers (de Sousa et al., 2010a). However, the molecular plane separation of the R22(13) motifs is 8.26 Å in the cycyclen structure, compared with 11.32 Å for the dimeric syn CyEA counterparts.
In conclusion, fusing a macrocycle to a hydroxycyclohexyl amino alcohol group permits controlled tailoring of hydrogen-bond interactions. Covalent linking of the reinforced amino alcohol group to an aza macrocycle is achieved at the expense of a potential amine H-atom donor. The hydrogen-bonding array is nevertheless enriched by hydrogen-bonding interactions between the macrocyclic heteroatoms. In (I), an infrequent N—H···N interaction between macrocyclic N atoms completes the formation of a helical structure bearing a continuous hydrophilic inner core. This encouraging result merits further investigation of macrocyclic amino alcohols as suitable building blocks for the noncovalent synthesis of organic nanotubes (Carrillo et al., 2012).