反应详情

In dry dimethylformamide, 0.5 g of 4-bromo-2,3-dihydrobenzo[b]thiepin-5(4H)-one, 0.6 g of silver tosylate and 0.2 g of lithium carbonate are heated under reflux for 12 hours, at the end of which time the reaction mixture is poured in ice-water. The resultant crystals are recovered by filtration and dried. This crude product is purified by thin-layer chromatography on silica gel (solvent system: benzene-n-hexane=1:3). The crude crystals thus obtained are recrystallized from methylene chloride-n-hexane. By the above procedure there is obtained 3-oxo-2,3-dihydro[1]-benzothiophene-2-spirocyclopropane as colorless prisms melting at 70° C.

1. temperatureunder reflux for 12 hours, at the end of which time the reaction mixture
2. filtrationThe resultant crystals are recovered by filtration
3. customdried
4. customThis crude product is purified by thin-layer chromatography on silica gel (solvent system: benzene-n-hexane=1:3)
5. customThe crude crystals thus obtained
6. customare recrystallized from methylene chloride-n-hexane