反应详情

2.195 g of (±)-6-fluoro-2,3-dihydro-2'-iminospiro-[4H-1-benzopyran-4,5'-thiazolidin]-4'-one were dissolved in 12 ml of methanol and 12 ml of 37% aqueous hydrochloric acid and the solution was boiled overnight. The colorless crystals which separated were removed and washed with water. After drying in vacuo, there was obtained (±)-6-fluoro-2,3-dihydrospiro[4H-1-benzopyran-4,5'-thiazolidine]-2',4'-dione of melting point 147°-149° C. (95% of theory).

1. customThe colorless crystals which separated
2. customwere removed
3. washwashed with water
4. customAfter drying in vacuo