反应详情

In 500 ml of carbon tetrachloride, 48.0 g of the (2S,5S)-2-tert-butyl-5-methyl-1,3-dioxolan-4-one obtained in Step 1 was dissolved. To the resulting solution, 54.0 g of N-bromosuccinimide and 1.0 ml of benzoyl peroxide were added, and the solution was refluxed for 2 hours. After the reaction solution was left to have cooled, insolubles were separated by filtration and the filtrate was successively washed with an aqueous 10% sodium thiosulfate solution, a saturated aqueous sodium hydrogencarbonate solution and a saturated brine. From the filtrate thus washed, the carbon tetrachloride was evaporated under reduced pressure, and the resulting residue was recrystallized from hexane to obtain 70.5 g of (2S,5S)-5-bromo-2-tert-butyl-5-methyl-1,3-dioxolan-4-one.

1. temperaturethe solution was refluxed for 2 hours
2. waitAfter the reaction solution was left
3. temperatureto have cooled
4. custominsolubles were separated by filtration
5. washthe filtrate was successively washed with an aqueous 10% sodium thiosulfate solution
6. washFrom the filtrate thus washed
7. customthe carbon tetrachloride was evaporated under reduced pressure
8. customthe resulting residue was recrystallized from hexane