1058
J. Kim et al.
100 ml) was added to the resulting oil to yield a colourless solution. The
solution was washed with dichloromethane (3×100 ml) and then its pH
was adjusted to 14 with sodium hydroxide. The solution was allowed to
cool. It was then extracted with dichloromethane (2×50 ml). The com-
bined dichloromethane phases were then washed with water (3×50 ml),
dried over anhydrous sodium sulfate, then filtered. The solvent was
removed in a rotary evaporator. The product that remained was recrys-
tallized from acetonitrile to yield colourless needle-like crystals (1.9 g,
47%), m.p. 134.6–134.9°C (Found: C, 77.4; H, 7.4; N, 7.2. C26H30N2O2
requires C, 77.6; H, 7.5; N, 7.0%). Mass spectral (e.i.) parent peak, m/z
402. 1H n.m.r. δ 1.79, 2H, q, NCH2CH2CH2N; 2.46, 2H, t, CH2CH2NH;
2.61, 2H, t, CH2CH2NCH2C6H5; 2.92, 1H, br, NH; 3.38, 2H, s,
ArCH2NH; 3.49, 2H, s, ArCH2NCH2C6H5; 3.68, 2H, s, CH2C6H5; 4.31,
4H, s, OCH2; 6.9–7.3, m, arom. 13C n.m.r. δ 26.5, NCH2CH2CH2N;
47.2, ArCH2NH; 49.1, ArCH2NCH2C6H5; 51.5, CH2CH2NH; 53.5,
CH2CH2NCH2C6H5; 58.4, CH2C6H5; 65.6, OCH2; 110.0, 119.8, 120.5,
128.4, 131.1, 133.0, 156.9, 157.4, arom., macrocycle; 126.3, 127.7,
128.9, 139.6, arom., benzyl.
lized with four molecules of acetone per unit cell, one-half
of a molecule of solvent (disposed on a crystallographic 2
axis) and one molecule of (11), devoid of crystallographic
symmetry, comprising the asymmetric unit of the structure.
The atomic coordinates are listed in Table 1 and bond
lengths and angles are given in Table 2. In contrast to the X-
ray structure of the corresponding (unsubstituted) 17-mem-
bered ring (10),10 which crystallizes in an unfolded
configuration, the structure of (11) shows a very convoluted
geometry. There is an absence of pseudo-symmetry relating
equivalent ‘halves’of the molecule, while reasonable agree-
ment between bond lengths for chemically equivalent bonds
in each ‘half’ is evident. As is well documented for other
structures containing –OCH2CH2O– strings,11 the C–C bond
between the ether oxygens in (11), at 1.486(3) Å, appears
slightly shorter than the average C–C length of 1.524(15) Å
for straight-chain alkane derivatives contained in the
Cambridge Structural Data Base.12 In this context, it is
noted that such shortening has been suggested to be largely
an artefact, with the ‘real’ component of the shortening
being quite minor.13 Other bond lengths in the structure
appear unremarkable.
Macrocycle (3). Benzyl bromide (3.42 g, 0.02 mol) and (1)
(3.12 g, 0.01 mol) were dissolved in acetonitrile (100 ml) containing
sodium carbonate (5.29 g, 0.05 mol). The mixture was heated at the
reflux overnight and then cooled and filtered. The solvent was removed
on a rotary evaporator then dilute hydrochloric acid (0.1 M, 100 ml) was
added to the residue with stirring. Undissolved residue was dissolved in
dichloromethane (50 ml). The acid/aqueous solution was extracted with
dichloromethane (3×100 ml). Both organic fractions were combined
and the resulting solution was washed with aqueous sodium hydroxide
(2×50 ml), dried over anhydrous sodium sulfate, filtered, and the
solvent removed on a rotary evaporator. The product that remained was
recrystallized from acetonitrile to yield colourless crystals (2.2 g, 45%),
m.p. 123.8–124.5°C (Found: C, 80.3; H, 7.6; N, 5.7. C33H36N2O2
requires C, 80.5; H, 7.4; N, 5.7%). Mass spectral parent peak (f.a.b.),
Experimental
1H and 13C n.m.r. spectra were recorded in (D)chloroform solution
on a Varian Unity 400 spectrometer at 400 and 100 MHz, respectively.
The e.i. mass spectra of (2) and (9) and positive-ion f.a.b. mass spectra
of (3), (5), and (11) were determined by using JEOL-DX 300/303 spec-
trometers. The e.s. mass spectrum of (7) was obtained on a Finnigan
LCQ-8 spectrometer. Melting points are uncorrected. The precursor
macrocycles (1), (4), (6), (8) and (10) used in the benzylation reactions
were prepared by literature procedures.1,7,10,14
1
m/z 493 (LH+). H n.m.r. δ 1.72, 2H, q, NCH2CH2CH2N; 2.50, 4H, t,
NCH2CH2; 3.53, 4H, s, ArCH2N; 3.63, 4H, s, CH2C6H5; 4.38, 4H, s,
OCH2; 6.9–7.3, m, arom. 13C n.m.r. δ 23.5, NCH2CH2CH2N; 51.1,
ArCH2N; 51.8, NCH2CH2; 58.0, CH2C6H5; 66.4, OCH2; 110.8, 120.3,
128.0, 128.1, 132.5, 157.2, arom., macrocycle; 126.5, 127.1, 128.8,
140.6, arom., benzyl.
X-Ray Crystallographic Data Collection and Structure Determination
Macrocycle (5). In a similar manner to that described above,
benzyl bromide (3.42 g, 0.02 mol) and (4) (3.26 g, 0.01 mol) gave the
crude product which was recrystallized from acetonitrile to yield
colourless crystals (2.2 g, 43%), m.p. 107.4–107.7°C (Found: C, 80.8;
H, 7.6; N, 5.6. C34H38N2O2 requires C, 80.6; H, 7.6; N, 5.5%). Mass
C41H45N3O2·0.5(CH3)2CO, M 640.84. Orthorhombic, space group
Pbcn, a 28.646(2), b 10.3600(8), c 24.664(2) Å, γ 7319.7(10) Å3.
Dc(Z = 8) 1.163 g cm–3; F(000) 2752. µMo 0.072 mm–1; specimen 0.2 by
0.3 by 0.4 mm. 2θmax 56.74°; Ntot 46061, Nind 9114 (Rint = 0.0964), No
3613; R1 0.0519, wR2 0.1218 for 434 parameters. Largest difference
peak and hole 0.265 and –0.233 e Å–3.
1
spectral parent peak (f.a.b.), m/z 507 (LH+). H n.m.r. δ 1.56, 2H, q,
NCH2CH2CH2N; 2.28, 2H, m, OCH2CH2CH2O; 2.30, 4H, t,
NCH2CH2; 3.51, 4H, s, ArCH2N); 3.55, 4H, s, CH2C6H5; 4.29, 4H, s,
OCH2; 6.9–7.3, m, arom. 13C n.m.r. δ 23.7, NCH2CH2CH2N; 29.1,
OCH2CH2CH2O; 51.7, ArCH2N; 52.0, NCH2CH2; 59.2, C6H5CH2;
64.8, OCH2; 113.0, 120.7, 128.0, 128.8, 131.8, 157.2, arom., macro-
cycle; 126.5, 128.0, 128.9, 140.0, arom., benzyl.
Colourless crystals of (11) suitable for X-ray diffraction were crys-
tallized from acetone solution over 5 days. A suitable crystal was
mounted on a Bruker SMART diffractometer equipped with a graphite-
monchromatized Mo Kα (λ 0.71073 Å) radiation source and a CCD
detector; 45 frames of two-dimensional diffraction images were col-
lected and processed to obtain the cell parameters and orientation
matrix. Data collection was performed at 298(2) K. A total of 1271
frames of two-dimensional diffraction images were collected, each of
which was exposed for 30 s. The structure was solved by direct methods
Macrocycle (7). In a similar manner to that described above,
benzyl bromide (3.42 g, 0.02 mol) and (6) (3.42 g, 0.01 mol) yielded the
product (2.6 g, 50%) as colourless crystals after recrystallization from
acetonitrile, m.p. 98.5–98.8°C (Found; C, 78.0; H, 7.3; N, 5.4.
C34H38N2O3 requires C, 78.1; H, 7.3; N, 5.4%). Mass spectral (e.s.)
parent peak, m/z 523 (LH+). 1H n.m.r. δ 2.69, 4H, s, NCH2CH2; 3.50,
4H, s, ArCH2; 3.64, 4H, s, CH2C6H5; 3.97, 4H, m, OCH2; 4.16, 4H, m,
and refined by full matrix least squares using SHELXTL software;15 the
2
quantity Σw(F2obs–F2
)
was minimized, with w = [σ2(Fobs)2+
calc
(0.0855P)2+P]–1, where P = (F2obs+2F2calc)/3. All non-hydrogen atoms
were refined with anisotropic displacement parameters, whereas the
hydrogen atoms were constrained at estimated positions. Material
deposited comprises hydrogen coordinates, torsion angles and
anisotropic displacement parameters and structure factors.*
OCH2; 6.9–7.3, m, arom. 13C n.m.r.
δ 50.8, ArCH2N; 52.1,
NCH2CH2N; 58.2, CH2C6H5; 68.2, 70.0, OCH2; 111.6, 120.5, 128.0,
131.5, 157.3, arom., macrocycle; 126.5, 127.9, 128.0, 140.2, arom.,
benzyl.
Macrocycle (9). In a similar manner to that described above,
benzyl bromide (3.42 g, 0.02 mol) and (8) (3.56 g, 0.01 mol) yielded the
product (2.4 g, 45%) as colourless crystals after recrystallization from
acetonitrile, m.p. 92.1–92.5°C (Found: C, 78.3; H, 7.4; N, 5.2.
C35H40N2O3 requires C, 78.3; H, 7.5; N, 5.2%). Mass spectral (e.i.)
Ligand Synthesis
Macrocycle (2). Benzyl bromide (1.71 g, 0.01 mol) and (1)
(3.12 g, 0.01 mol) were dissolved in acetonitrile (100 ml) and sodium
carbonate (5.29 g, 0.05 mol) was added. The mixture was heated at the
reflux overnight and then cooled and filtered. The solvent was removed
on a rotary evaporator and then dilute hydrochloric acid (0.1 mol dm–3,
1
parent peak, m/z 536. H n.m.r. δ 1.85, 2H, q, NCH2CH2CH2N; 2.39,
4H, t, CH2N; 3.54, 4H, s, ArCH2; 3.70, 4H, s, CH2C6H5; 4.04, 4H, m,
* Copies are available (until 31 December 2004) from the Australian Journal of Chemistry, P.O. Box 1139, Collingwood, Vic. 3066.
Kim, Jeong
