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CHEN GuoHong, et al. Sci China Chem June (2010) Vol.53 No.6
silica gel column chromatography (EtOAc/petroleum ether
= 1/1) to yield the corresponding compound 7b.
1.78 (br, 1H), 2.20–2.27 (m, 1H), 2.35 (s, 3H), 2.67–2.82
(dd, 2H), 3.85–3.88 (m, 1H), 5.15–5.19 (m, 2H), 5.83–5.93
(m, 1H), 7.12–7.24 (m, 4H).
White solid; yield: 90%; mp 190–193 °C, []D20 = +58.2
(c 0.55, CHCl3) (Lit. [26]: mp 185–187 °C, yield 91%, []D29
1-(4-(Chloromethyl)phenyl)pent-4-en-2-ol (Table 2, entry 3)
1
= +60.4 (c 0.55, CHCl3)); H NMR (400 MHz, CDCl3):
1
White solid; yield 67%; H NMR (400 MHz, CDCl3):
1.74–1.79 (m, 1H), 2.04–2.09 (m, 1H), 2.27–2.30 (m, 1H),
2.51–2.54 (m, 1H), 2.84–2.89 (m, 1H), 3.20–3.24 (m, 1H),
3.57–3.60 (d, J = 7.2 Hz, 1H), 3.67–3.70 (d, J=7.2 Hz, 1H),
4.47–4.52 (m, 1H), 7.16–7.36 (m, 11H), 7.57–7.60 (m, 2H),
7.86–7.89 (m, 2H), 11.96 (br. s, 1H).
2.18–2.38 (m, 2H), 2.71–2.84 (m, 2H), 3.85–3.91 (m, 1H),
4.58 (s, 2H), 5.15–5.19 (m, 2H), 5.81–5.91 (m, 1H),
7.22–7.24 (d, 2H), 7.33–7.35 (d, 2H).
1-(4-Bromophenyl)pent-4-en-2-ol (Table 2, entry 4)
1
White solid; yield 53%; H NMR (400 MHz, CDCl3):
8-Hydroxyquinoline 1-oxide 7c
2.16–2.37 (m, 2H), 2.65–2.79 (m, 2H), 3.83–3.87 (m, 1H),
5.14–5.18 (m, 2H), 5.78–5.89 (m, 1H), 7.09–7.11 (d, 2H),
7.42–7.44 (d, 2H).
8-hydroxyquinoline 1-oxide 7c was prepared according to
the previous report [27]. Hydrogen peroxide (4 mL, 30% in
water) was added dropwise to a solution of commercially
available 8-hydroxyquinoline (1.5 g, 10.35 mmol) in acetic
acid (20 mL), and the solution was refluxed for 40 min.
After completion of the reaction, as indicated by TLC, the
mixture was allowed to warm slowly to room temperature
and aqueous Na2SO3 was added. The resulting contents
were extracted with dichloromethane (3 × 30 mL). The
combined organic layers were washed with saturated Na-
HCO3 aqueous solution, brine and dried over anhydrous
MgSO4. The solvent was evaporated at reduced pressure to
yield a solid, which was purified by silica gel column
chromatography (EtOAc/petroleum ether = 1/3) to yield the
corresponding compound 7c.
1-(4-Chlorophenyl)pent-4-en-2-ol (Table 2, entry 5)
1
Colorless oil; yield 29%; H NMR (400 MHz, CDCl3):
2.16–2.36 (m, 2H), 2.67–2.81 (m, 2H), 3.83–3.85 (m, 1H),
5.14–5.18(m, 2H), 5.81–5.88(m, 1H), 7.15–7.17 (d, 2H),
7.26–7.29 (d, 2H).
2.5 General procedure for ring-opening of epoxides
with allyltin tribromide in the presence of catalyst 7b
To a stirred solution of allyltin tribromide (0.25 mmol, 0.50
equiv) and compound 7b (0.275 mmol, 0.55 equiv) in
CH2Cl2 (3 mL) was added epoxide 1 (0.5 mmol), and the
reaction mixture was stirred at room temperature. After
completion of the reaction, as indicated by TLC, the reac-
tion mixture was quenched with saturated sodium bicarbon-
ate (2 mL) and extracted with chloroform (3 × 5 mL). The
combined extracts were dried over anhydrous sodium sul-
fate, and concentrated in vacuo. The residue was purified by
column chromatography on silica gel (n-hexane/EtOAc, 6:1
as eluent) to yield the corresponding products.
Yellow solid; yield 51%; 1H NMR (400 MHz, CDCl3):
3
4
7.04–7.07 (dd, J = 7.9 Hz, J = 0.9 Hz, 1H), 7.22–7.26 (m,
2H), 7.46–7.50 (t, 3J=8.0 Hz, 1H), 7.77–7.79 (d, 3J=8.4 Hz,
1H), 8.22–8.24 (d, 3J = 6.0 Hz, 1H).
2.4 General procedure for allylation of epoxides with
allyltin tribromide
To a stirred solution of allyltin tribromide (200 mg, 0.5
mmol) and L-proline (0.5 mmol, 1.0 equiv) in THF (3 mL)
was added epoxide 1 (0.6 mmol, 1.2 equiv), and the reaction
mixture was stirred at room temperature. After completion
of the reaction, as indicated by TLC, the reaction mixture
was quenched with saturated sodium bicarbonate (2 mL)
and extracted with chloroform (3 × 5 mL). The combined
extracts were dried over anhydrous sodium sulfate, and
concentrated in vacuo. The residue was purified by column
chromatography on silica gel (n-hexane/EtOAc, 10:1 as
eluent) to yield the desired products.
2-Bromo-2-phenylethanol (Table 4, entry 1)
1
Colorless oil; yield 96%; H NMR (400 MHz, CDCl3):
2.51 (br s, 1H), 3.93–4.09 (dd, 2H), 5.03–5.07 (m, 1H),
7.33–7.43 (m, 5H).
2-Bromo-2-(4-(chloromethyl)phenyl)ethanol (Table 4, entry 2)
1
Colorless oil; yield 80%; H NMR (400 MHz, CDCl3):
2.60 (br s, 1H), 3.95–4.04 (m, 2H), 4.58 (s, 3H), 5.04 (m,
1H), 7.38–7.43 (m, 4H).
2-Bromo-1,2-diphenylethanol (Table 4, entry 3)
1-Phenylpent-4-en-2-ol (Table 2, entry 1)
1
1
Colorless oil; yield 89%; H NMR (400 MHz, CDCl3):
3.09 (br s, 1H), 5.04–5.16 (m, 2H), 7.12–7.24 (m, 10H).
Colorless oil; yield 88%; H NMR (400 MHz, CDCl3):
2.19–2.37 (m, 2H), 2.70–2.85 (m, 2H), 3.86–3.90 (m, 1H),
5.14–5.19 (m, 2H), 5.84–5.91 (m, 1H), 7.22–7.34 (m, 5H).
1-Bromo-3-phenoxypropan-2-ol (Table 4, entry 4)
1
1-p-Tolylpent-4-en-2-ol (Table 2, entry 2)
Colorless oil; yield 96%; H NMR (400 MHz, CDCl3):
2.85–2.87 (m, 1H), 3.61–3.69 (m, 2H), 4.08–4.22 (m, 3H),
1
Colorless oil; yield: 72%; H NMR (400 MHz, CDCl3):