反应详情

Pyrrolidine (2.4 mL) was added to a solution of 2'-hydroxy-5'-fluoroacetophenone (15.1 g) and 3-phenylpropanal (13.2 mL) in toluene (30 mL), and the mixture heated under reflux in a Dean-Stark apparatus for 3 hours, cooled, diluted with ethyl acetate and washed with aqueous 1N HCl, aqueous 1N NaOH, H2O, brine, dried (Na2SO4), filtered and evaporated, and the residue purified by column chromatography (6:1 hexane/diethyl ether, SiO2) to yield 2,3-dihydro-6-fluoro-2-(2-phenylethyl)-4H-1-benzopyran-4-one (18 gm, Rf=0.3 4:1 hexane/diethyl ether).

1. temperaturethe mixture heated
2. temperatureunder reflux in a Dean-Stark apparatus for 3 hours
3. temperaturecooled
4. washwashed with aqueous 1N HCl, aqueous 1N NaOH, H2O, brine
5. dry with materialdried (Na2SO4)
6. filtrationfiltered
7. customevaporated
8. customthe residue purified by column chromatography (6:1 hexane/diethyl ether, SiO2)