反应详情

To a suspension of methyl(triphenyl)phosphonium bromide (8.13 g, 22.3 mmol) in THF (44 mL) was added n-butyllithium (1.65 M in n-hexane, 13.5 mL, 22.3 mmol) in a dry ice-acetone bath under argon atmosphere. The mixture was stirred for 60 minutes in an ice bath. To the mixture was added a mixture of 6-bromo-2,2-dimethyl-4H-spiro[chromene-3,3′-oxetan]-4-one (2.21 g, 7.44 mmol) and THF (11 mL) in an ice bath. The mixture was stirred for 1 hour at ambient temperature. The reaction was quenched by adding water in an ice-water bath. The mixture was partitioned between EtOAc-hexane (1:2) and water. The organic layer was washed with brine, dried over MgSO4, filtered, and the filtrate was evaporated. Purification using silica gel column chromatography (EtOAc-hexane, a linear gradient of EtOAc from 0 to 20%) afforded 6-bromo-2,2-dimethyl-4-methylene-4H-spiro[chromene-3,3′-oxetane] (2.02 g).

1. additionTo the mixture was added
2. stirringThe mixture was stirred for 1 hour at ambient temperature
3. customThe reaction was quenched
4. additionby adding water in an ice-water bath
5. customThe mixture was partitioned between EtOAc-hexane (1:2) and water
6. washThe organic layer was washed with brine
7. dry with materialdried over MgSO4
8. filtrationfiltered
9. customthe filtrate was evaporated
10. customPurification