反应详情

5-Bromo-2-methoxypyridine (15.87 g) was dissolved in dry tetrahydrofuran (50 ml) and the solution cooled with mechanical stirring under nitrogen to -100° (ether/liquid nitrogen). A solution of n-butyl lithium in hexane (53 ml of a 1.6M solution) was added dropwise, maintaining the temperature below -90°; a white precipitate appeared. After 5 minutes, 5-benzyloxy-2-methoxybenzaldehyde (17.04 g) in dry tetrahydrofuran (150 ml) was added dropwise, maintaining the temperature below -95°. After the addition was complete, the mixture was stirred to 5°. The dark solution was quenched with excess saturated ammonium chloride, the organic layer removed, the aqueous extracted with ethyl acetate, then the combined organics dried with anhydrous magnesium sulphate and evaporated. The residue crystallised from ether/petroleum spirit to give 1-(5-benzyloxy-2-methoxyphenyl)-1-(6-methoxy-3-pyridyl)methanol (17.83 g, 72%), m.p. 80°-82°.

1. temperaturethe solution cooled
2. temperaturemaintaining the temperature below -90°
3. temperaturemaintaining the temperature below -95°
4. additionAfter the addition
5. customThe dark solution was quenched with excess saturated ammonium chloride
6. customthe organic layer removed
7. extractionthe aqueous extracted with ethyl acetate
8. dry with materialthe combined organics dried with anhydrous magnesium sulphate
9. customevaporated
10. customThe residue crystallised from ether/petroleum spirit