反应详情

59.0 g (0.25 mol) of ethyl 8-methoxy-chroman-2-carboxylate in 525 ml of anhydrous tetrahydrofuran are added dropwise in the course of 1 h, with stirring, at 20° C. to a suspension of 9.5 g (0.25 mol) of lithium aluminium hydride in 525 ml of anhydrous diethyl ether. The batch is stirred overnight and 9.5 ml of water, 9.5 ml of 15% strength sodium hydroxide solution and 28.4 ml of water are then successively added dropwise, with cooling. The organic phase is decanted off and evaporated. The residue is recrystallised twice from dichloromethane/petroleum ether. Yield: 38.0 g (87%) Melting point: 57°-58° C.

1. temperaturewith cooling
2. customThe organic phase is decanted off
3. customevaporated
4. customThe residue is recrystallised twice from dichloromethane/petroleum ether