反应详情

To a mixture of 14.5 g of (±)-trans-3-bromo-6-cyano-3,4-dihydro-2,2-dimethyl-4-hydroxy-2H-1-benzopyran, 60 ml of ethylene chloride and 1.6 ml of pyridine was added 5.5 g of (S)-(-)-3-(3,5-dinitrobenzoylthio)-2-methylpropionyl chloride under ice-cooling and was stirred for 1.5 hours under room temperature. The reaction mixture was washed with diluted hydrochloric acid once and 10% aqueous sodium chloride solution twice. The organic layer was separated, dried over magnesium sulfate and concentrated under reduced pressure to give 8.9 g of (±)-trans-3-bromo-6-cyano 3,4-dihydro-2,2-dimethyl-4-[(S)-(-)-3-(3,5-dinitrobenzoylthio)-2-methylpropionyloxy]-2H-1benzopyran as light yellow semicrystals.

1. temperaturecooling
2. washThe reaction mixture was washed with diluted hydrochloric acid once
3. customThe organic layer was separated
4. dry with materialdried over magnesium sulfate
5. concentrationconcentrated under reduced pressure