Synthesis of compound 21. Under nitrogen, compound 20
(3.5 g, 6.5 mmol) and 4-hexyloxy benzaldehyde (2.7 g, 13 mmol)
were dissolved in dry THF (50 mL). Potassium t-butoxide (1.6 g,
14 mmol) was dissolved in dry THF separately and added dropwise
to the reaction mixture and stirred overnight at room temperature.
Methanol (100 mL) was added into the reaction mixture and all
the volatiles were removed under reduced pressure. The residue
was dissolved in CH2Cl2 (150 mL) and extracted with water (3
¥ 100 mL). The organic layer was collected, dried over sodium
sulfate and removed under reduced pressure, yielding a yellow
solid. The crude solid was recrystallized from pure hexane (4.5 g,
addition of [Pd(PPh3)4] (0.11 g, 0.10 mmol) and copper iodide
(19 mg, 0.10 mmol). Compound 23 (0.20 g, 0.40 mmol) was
dissolved in triethylamine (20 mL) separately and added dropwise
to the reaction mixture and stirred for 48 h at 85 ◦C. The reaction
mixture was passed through silica, followed by washing with ether
(40 mL). The organic layer was extracted with saturated sodium
bicarbonate solution (4 ¥ 100 mL) followed by extraction with
50% aqueous HCl solution (3 ¥ 50 mL) and finally the aqueous
layer was neutralized with NaOH pellets. This aqueous layer was
extracted with ether (3 ¥ 30 mL). The organic layer was collected,
dried over sodium sulfate and evaporated under reduced pressure.
The residue was dissolved in the minimum amount of pentane and
left to crystallize. The solid precipitate was filtered off as a pale
yellow solid (0.30 g, 86%). 1H NMR (300 MHz, CDCl3): d = 0.90
– 0.96 (b, 6H; 2 ¥ CH3), 1.52 – 1.34 (m, 12H; 6 ¥ CH2), 1.82 (t,
4H; J = 9.0 Hz, 2 ¥ CH2), 2.30 (s, 24H; 8 ¥ N–CH3), 3.47 (s, 8H;
4 ¥ N–CH2), 4.01 (t, 4H; J = 9.0 Hz, 2 ¥ O–CH2), 6.94 (d, 4H;
J = 9.0 Hz, Aromatic), 7.24 (d, 2H; J = 15 Hz, HC CH), 7.32
(s, 2H; Aromatic), 7.58 – 7.49 (m, 10H; Aromatic), 7.88 (s, 2H;
Aromatic). 13C NMR (75 MHz, CDCl3): d = 14.1, 22.6, 25.7, 29.2,
31.6, 45.5, 64.0, 68.1, 87.9, 95.5, 114.8, 122.0, 123.0, 123.5, 128.1,
128.6, 129.9, 130.1, 130.9, 137.3, 139.4, 159.2. HRMS (M+H)+:
calc’d for C62H79O2N4: 911.6203; found, 911.6195.
1
54%). H NMR (300 MHz, CDCl3): d = 0.94 (b, 6H; 2 ¥ CH3),
1.52 – 1.34 (m, 12H; 6 ¥ CH2), 1.82 (q, 4H; J = 6.0 Hz, 2 ¥ CH2),
4.01 (t, 4H; J = 6.0 Hz, 2 ¥ O–CH2), 6.92 (d, 4H; J = 9.0 Hz,
Aromatic), 7.02 (d, 2H; J = 18 Hz, HC CH), 7.24 (d, 2H; J = 18
Hz, HC CH), 7.50 (d, 4H; J = 9.0 Hz, Aromatic), 7.86 (s, 2H,
Aromatic). 13C NMR (75 MHz, CDCl3): d = 14.0, 22.6, 25.7, 29.2,
31.6, 68.1, 114.8, 122.8, 123.5, 128.3, 129.3, 130.0, 131.7, 137.8,
159.5. MALDI: calc’d for C34H40Br2O2: 638.1; found, 637.9.
Synthesis of compound 22. Under nitrogen, compound 21
(2.0 g, 3.1 mmol) was dissolved in toluene (20 mL) followed by
the addition of [Pd(PPh3)4] (0.40 g, 0.4 mmol) and copper iodide
(0.070 mg, 0.4 mmol). Trimethylsilylacetylene (1.2 g, 12 mmol)
was dissolved in triethylamine (30 mL) separately and added
dropwise to the reaction mixture and stirred for 48 h at 85 ◦C.
Ether (100 mL) was added to the reaction mixture and the organic
layer was extracted with saturated sodium bicarbonate solution
(4 ¥ 150 mL), dried over sodium sulfate and evaporated under
reduced pressure. The residue was dissolved in ether and passed
through silica followed by washing with CHCl3 (2 ¥ 50 mL). The
organic layer was collected and removed under reduced pressure,
Synthesis of compound 25. Under nitrogen, compound 20
(5.70 g, 10.6 mmol) and 4-t-butylbenzaldehyde 24 (3.45 g,
21.3 mmol) were dissolved in dry THF (50 mL). Potassium t-
butoxide (2.62 g, 23.4 mmol) was dissolved in dry THF separately
and added dropwise to the reaction mixture and stirred overnight
at room temperature. Methanol (100 mL) was added into the
reaction mixture and all the volatiles were removed under reduced
pressure. The residue was dissolved into CH2Cl2 (150 mL) and
extracted with water (3 ¥ 100 mL). The organic layer was collected,
dried over sodium sulfate and the solvent removed under reduced
pressure, yielding a light yellow solid (3.5 g, 60%). 1H NMR
(300 MHz, CDCl3): d = 1.38 (s, 18H; 6 ¥ CH3), 7.09 (d, 2H;
J = 16 Hz, HC CH), 7.39 (d, 2H; J = 16 Hz, HC CH), 7.46 (d,
4H; J = 8.4 Hz, Aromatic), 7.54 (d, 4H; J = 8.4 Hz, Aromatic),
7.89 (s, 2H; Aromatic). 13C NMR (75 MHz, CDCl3): d = 31.2,
34.7, 123.0, 125.1, 125.7, 126.7, 130.2, 131.9, 133.9, 137.3, 151.7.
MALDI: calc’d for C30H32Br2: 550.1; found, 550.2.
1
yielding a light yellow solid (1.1 g, 48%). H NMR (300 MHz,
CDCl3): d = 0.34 (s, 18H; 6 ¥ Si–CH3), 0.94 (t, 6H; J = 9.0 Hz, 2
¥ CH3), 1.52 – 1.34 (m, 12H; 6 ¥ CH2), 1.82 (q, 4H; J = 6.0 Hz,
2 ¥ CH2), 4.01 (t, 4H; J = 6.0 Hz, 2 ¥ O–CH2), 6.92 (d, 4H; J =
9.0 Hz, Aromatic), 7.17 (d, 2H; J = 18 Hz, HC CH), 7.4–7.6 (m,
6H; Aromatic and HC CH), 7.79 (s, 2H; Aromatic). 13C NMR
(75 MHz, CDCl3): d = 0.0, 14.1, 22.6, 25.7, 29.2, 31.6, 68.1, 100.7,
103.4, 114.8, 121.9, 123.3, 127.9, 128.4, 129.9, 130.0, 137.6, 159.2.
MALDI: calc’d for C44H58O2Si2: 674.4; found, 674.3.
Synthesis of compound E. Under nitrogen, compound 25 was
dissolved in DMF (20 mL) followed by the addition of [Pd(PPh3)4]
(44 mg, 0.040 mmol) and copper iodide (3.2 mg, 0.010 mmol).
Compound 27 was dissolved in triethylamine (20 mL) separately
and added dropwise to the reaction mixture and stirred for 48 h
at 85 ◦C. Ether (20 mL) was added into the reaction mixture and
washed with saturated sodium bicarbonate solution (4 ¥ 50 mL).
The organic layer was collected, dried over sodium sulfate and
removed under reduced pressure. Ether (20 mL) was added to the
residue and washed with concentrated 25% aq. H2SO4 solution
(v:v) (2 ¥ 25 mL). The aqueous layer was collected and neutralized
by adding NaOH pellets (pH ~ 10). The aqueous layer was
extracted with ether (3 ¥ 20 mL). The organic layer was collected,
dried over sodium sulfate and the solvent removed under reduced
pressure, yielding a pale yellow solid. Finally the compound
was purified over preparative TLC (CH2Cl2/Methanol, 200 : 1).
Synthesis of compound 23. Compound 22 (0.50 g, 0.70 mmol),
was dissolved in THF (30 mL) followed by the addition of
tetrabutylammonium fluoride trihydrate (2.2 g, 7.0 mmol) and
stirred for 2 h at room temperature. Volatiles were removed under
reduced pressure and ether (30 mL) was added into the residue
followed by extraction with saturated bicarbonate solution (4 ¥
50 mL). The organic layer was collected, dried over sodium sulfate
and evaporated under reduced pressure, yielding a yellow solid
(0.35 g, 88%). 1H NMR (300 MHz, CDCl3): d = 0.93 (t, 6H; J =
9.0 Hz, 2 ¥ CH3), 1.52 – 1.34 (m, 12H; 6 ¥ CH2), 1.82 (q, 4H; J =
6.0 Hz, 2 ¥ CH2), 3.47 (s, 2H; C CH), 4.01 (t, 4H; J = 6.0 Hz,
2 ¥ O–CH2), 6.92 (d, 4H; J = 9.0 Hz, Aromatic), 7.15 (d, 2H; J =
15 Hz, HC CH), 7.44 (d, 2H; J = 15 Hz, HC CH), 7.50 (d, 4H;
J = 9 Hz, Aromatic), 7.84 (s, 2H; Aromatic). MALDI: calc’d for
C38H42O2: 530.3; found, 530.4.
1
Synthesis of compound D. Under nitrogen, compound 3
(0.020 g, 10%) H NMR (300 MHz, CDCl3): d = 1.37 (s, 18H;
(0.28 g, 0.80 mmol) was dissolved in DMF (40 mL) followed by
C–CH3), 2.23 (s, 24H; N–CH3), 3.51 (s, 8H; N–CH2), 7.25–7.33
This journal is
The Royal Society of Chemistry 2010
Org. Biomol. Chem., 2010, 8, 5620–5627 | 5623
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