反应详情

A 2-liter, 3-neck flask equipped with a nitrogen inlet, internal thermometer, mechanical stirrer, and reflux condenser was charged with 5-hydroxy-2,3-dihydrobenzofuran-6-carboxaldehyde (50.00 g; 0.30 moles), benzylbromide (38.6 ml, 0.34 moles), and crushed anhydrous K2CO3 (165.84 g, 1.20 moles). The reaction mixture was refluxed for 16 hours, cooled to room temperature and suction filtered. The filtrate was concentrated in vacuo to afford a yellow solid. The solid was dissolved in methylene chloride (600 ml) and washed sequentially with 0.5N sodium hydroxide solution (3×250 ml) and brine (2×250 ml). The organic phase was dried over MgSO4, suction filtered, and the filtrate concentrated in vacuo to yield a crude solid (85 g). The solid was dissolved in methylene chloride (300 ml)/n-hexane (200 ml), treated with charcoal and suction filtered through a bed of celite. The filtrate was evaporated in vacuo to approximately 300 ml and slowly cooled to 0° C. to produce yellowish flat needles (60 g, 78%).

1. customA 2-liter, 3-neck flask equipped with a nitrogen inlet
2. temperatureinternal thermometer, mechanical stirrer, and reflux condenser
3. temperatureThe reaction mixture was refluxed for 16 hours
4. filtrationsuction filtered
5. concentrationThe filtrate was concentrated in vacuo
6. customto afford a yellow solid
7. washwashed sequentially with 0.5N sodium hydroxide solution (3×250 ml) and brine (2×250 ml)
8. dry with materialThe organic phase was dried over MgSO4, suction
9. filtrationfiltered
10. concentrationthe filtrate concentrated in vacuo
11. customto yield a crude solid (85 g)
12. filtrationfiltered through a bed of celite
13. customThe filtrate was evaporated in vacuo to approximately 300 ml
14. temperatureslowly cooled to 0° C.