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Can. J. Chem. Vol. 76, 1998
temperature, it was acidified with 1 M HCl (10 mL) and ex-
tracted with CH2Cl2 (100 mL × 2). The combined extracts
were washed with water (50 mL × 2), dried (Na2SO4), and
condensed under reduced pressure to give a yellow oil. The
yellow precipitate was obtained by adding Et2O (5 mL),
which was recrystallized from methanol to give partial-cone-
2 (184 mg, 21%). The ethereal filtrate was condensed in
vacuo to leave a residue, which was chromatographed on sil-
ica gel with methanol as an eluent to give cone-2 (88 mg,
10%).
was obtained by adding Et2O (10 mL), which was
recrystallized from methanol to give partial-cone-2 (552 mg,
62%). The ethereal filtrate was condensed in vacuo to leave
a residue, which was chromatographed on silica gel with
methanol as an eluent to give cone-2 (70 mg, 8%).
Benzylation of 1 with benzyl bromide in the presence
of Cs2CO3
A mixture of 1 (100 mg, 0.174 mmol) and Cs2CO3
(567 mg, 1.74 mmol) in acetone (10 mL) was heated at re-
flux for 1 h. Then benzyl bromide (0.21 mL, 1.74 mmol)
was added and the mixture heated at reflux for 17 h. After
cooling the reaction mixture to room temperature, it was fil-
tered. The filtrate was concentrated, and the residue was ex-
tracted with CH2Cl2 (2 × 100 mL) and washed with water
(2 × 50 mL), dried (Na2SO4), and condensed under reduced
pressure. The residue was washed with methanol to give the
crude partial-cone-3 (139 mg, 95%) as a colorless solid.
Recrystallization from methanol/CHCl3 (3:1) gave partial-
cone-7,15,23-tri-tert-butyl-25,26,27-tris(benzyloxy)-2,3,10,11,
18,19-hexahomo-3,11,19-trioxacalix[3]arene (partial-cone-3)
as colorless prisms (MeOH/CHCl3 (3:1)); mp 180–185°C;
1H NMR (CDCl3): 0.93 (s, 18 H), 1.20 (s, 9 H,), 3.40 (s, 2
H, OCH2Ph), 4.07 (d, 2 H, J 12.7), 4.15 (d, 2 H, J 12.2,
OCH2Ph), 4.19 (d, 2 H, J 12.2, OCH2Ph), 4.27 (d, 2 H, J
9.3), 4.28 (d, 2 H, J 12.7), 4.46 (d, 2 H, J 12.7), 4.53 (d, 2
H, J 12.7), 4.54 (d, 2 H, J 9.3), 6.72–6.78 (m, 2 H), 7.01–
7.14 (m, 17 H), 7.29 (s, 2 H); MS, m/z: M+ 846. Anal. calcd.
for C57H66O6: C 80.82, H 7.85; found: C 80.53, H 7.73.
Partial-cone-7,15,23-tri-tert-butyl-25,26,27-tris[(2-
pyridylmethyl)oxy]-2,3,10,11,18,19-hexahomo-3,11,19-
trioxacalix[3]arene (partial-cone-2)
Colorless prisms [MeOH/CHCl3 (3:1)]; mp 172–173°C;
1H NMR (CDCl3): 0.99 (18 H, s), 1.14 (9 H, s), 4.12 (2 H, s,
OCH2Py), 4.14 (2 H, d, J 11.2), 4.22 (d, 2 H, J 12.2), 4.27
(d, 2 H, J 10.7), 4.53 (d, 2 H, J 10.7), 4.65 (d, 2 H, J 12.7,
OCH2Py), 4.74 (d, 2 H, J 12.7, OCH2Py), 4.83 (d, 2 H, J
12.2), 4.97 (d, 2 H, J 11.2), 6.45 (d, 1 H, J 7.8, H3′), 6.96
(m, 2 H, H5), 7.00 (d, 2 H, J 7.8, H3), 7.06 (m, 1 H, H5′),
7.17 (d, 2 H, J 2.4), 7.24 (d, 2 H, J 2.4), 7.34 (ddd, 2 H, J
2.0, 7.3, 7.8, H4), 7.37 (s, 2 H), 7.56 (ddd, 1 H, J 2.0, 7.3,
7.8, H4′), 8.31 (d, 1 H, J 4.9, H6′), 7.34 (d, 2 H, J 4.9, H6);
MS, m/z: M+ 850. Anal. calcd. for C54H63N3O6: C 76.3, H
7.47, N 4.94; found: C 75.95, H 7.28, N 4.86.
1
The splitting pattern in H NMR shows that the isolated
compound is partial-cone-2.
1
The splitting pattern in H NMR shows that the isolated
Cone-7,15,23-tri-tert-butyl-25,26,27-tris[(2-
pyridylmethyl)oxy]-2,3,10,11,18,19-hexahomo-3,11,19-
trioxacalix[3]arene (cone-2)
compound is partial-cone-3.
Colorless prisms (MeOH/CHCl3 (3:1)); mp 166–168°C;
1H NMR (CDCl3): 1.12 (s, 27 H), 4.63 (d, 6 H, J 13.2,
CH2OCH2, eq), 4.65 (d, 6 H, J 13.2, CH2OCH2, ax), 4.73 (s,
6 H, OCH2Py), 7.05 (s, 6 H, ArH), 7.09 (m, 3 H, H5), 7.33
(ddd, 3 H, J 2.0, 7.3, 7.8, H4), 7.50 (d, 3 H, J 7.8, H3), 8.49
(d, 3 H, J 4.9, H6); MS, m/z: M+ 850. Anal. calcd. for
C54H63N3O6: C 76.3, H 7.47, N 4.94; found: C 76.13, H
7.29, N 4.80.
Preparation of 4-tert-butyl-2,6-dimethyl[(2-
pyridylmethyl)oxy]benzene 4
A mixture of 4-tert-butyl-2,6-dimethylphenol (400 mg,
2.25 mmol) and NaH (580 mg, 14.5 mmol, 60%) in dry THF
(20 mL) was heated at reflux for 1 h under N2. Then a solu-
tion of 2-(chloromethyl)pyridine (14.5 mmol) (prepared by
neutralization of 2-(chloromethyl)pyridine hydrochloride
(2.38 g, 14.5 mmol) in DMF (15 mL) with a solution of
triethylamine (2.02 mL, 14.52 mmol) in THF (25 mL) at
room temperature) was added and the mixture heated at re-
flux for an additional 17 h. After cooling the reaction mix-
ture to room temperature, it was acidified with 1 M HCl
(10 mL) and extracted with CH2Cl2 (100 mL × 2). The com-
bined extracts were washed with water (50 mL × 2), dried
(Na2SO4), and condensed under reduced pressure to give a
yellow oil. The residue was chromatographed on silica gel
with methanol as an eluent to give the title compound 4
(380 mg, 63%) as a colorless oil; 1H NMR (CDCl3): 1.30 (s,
9 H), 2.31 (s, 6 H), 4.95 (s, 2 H), 7.05 (s, 2 H), 7.20 (m, 1
H, H5), 7.74 (m, 2 H, H3 and H4), 8.58 (dd, 1 H, J 0.9, 4.9,
H6); MS, m/z: M+ 269. Anal. calcd. for C18H23NO: C 80.26,
H 8.61, N 5.2; found: C 80.55, H 8.49, N 4.98.
1
The splitting pattern in H NMR shows that the isolated
compound is cone-2.
Alkylation of 1 with 2-(chloromethyl)pyridine in the
presence of Cs2CO3
A mixture of 1 (600 mg, 1.04 mmol) and Cs2CO3 (3.39 g,
10.4 mmol) in dry THF (12 mL) was heated at reflux for 2 h
under N2. Then a solution of 2-(chloromethyl)pyridine
(10.4 mmol) (prepared by neutralization of 2-(chloro-
methyl)pyridine hydrochloride (1.71 g, 10.4 mmol) in DMF
(10 mL) with a solution of triethylamine (1.45 mL,
10.4 mmol) in THF (20 mL) at room temperature) was
added and the mixture heated at reflux for an additional
17 h. After cooling the reaction mixture to room tempera-
ture, it was filtered. The filtrate was concentrated, and the
residue was extracted with CH2Cl2 (2 × 100 mL) and
washed with water (2 × 50 mL), dried (Na2SO4), and con-
densed under reduced pressure. The 1H NMR analyses of the
residue was in accord with its being a mixture of cone-2 and
partial-cone-2 in the ratio of 12:88. The yellow precipitate
Picrate extraction measurements
Alkali metal picrates (2.5 × 10–4 M) were prepared in situ
by dissolving the alkali metal hydroxide in 2.5 × 10–4 M pic-
ric acid; triply distilled water was used for all aqueous solu-
tions. Similarly, silver picrate was prepared in situ by
© 1998 NRC Canada