Реакция #172396
ord-69c786a9737c47cc97242a66e059c0b4
Уравнение реакции
Реактанты
Реагенты
Условия реакции
Обработка
- 1ТемператураCooling
- 2Другоеis removed
- 3ТемператураThe mixture is then again cooled to 5° C.
- 4workup.ADDITION400 ml of 1N aqueous sodium hydroxide solution are added
- 5workup.ADDITIONAfter the addition
- 6workup.ADDITION81 ml of 30% strength hydrogen peroxide solution are added a little at a time at this temperature
- 7ПромывкаAfter dilution with 500 ml of ethyl acetate, the mixture is washed with 32 ml of 40% strength sodium bisulphite solution
- 8Другоеto destroy the peroxides
- 9ДругоеThe organic phase is separated off
- 10Экстракцияthe aqueous phase is extracted four times with ethyl acetate
- 11ПромывкаThe combined organic phases are washed with saturated sodium chloride solution
- 12Сушкаdried over magnesium sulphate
- 13Фильтрацияafter filtration
- 14Концентрированиеconcentrated to dryness under reduced pressure
- 15ДругоеThe residue is chromatographed on silica gel using a gradient of cyclohexane and ethyl acetate
- 16Концентрированиеconcentrated to dryness under reduced pressure
Методика
23 g (80 mmol) of the compound from Example 29A are dissolved in 80 ml of anhydrous tetrahydrofuran and cooled to 5° C. Over a period of 15 min, 21 g (176 mmol) of 9-borabicyclo[3.3.1]nonane (0.5M solution in tetrahydrofuran) are added. Cooling is removed, and the mixture is stirred at room temperature for another 2 h. The mixture is then again cooled to 5° C., and 400 ml of 1N aqueous sodium hydroxide solution are added. After the addition has ended, 81 ml of 30% strength hydrogen peroxide solution are added a little at a time at this temperature. After dilution with 500 ml of ethyl acetate, the mixture is washed with 32 ml of 40% strength sodium bisulphite solution to destroy the peroxides. The organic phase is separated off, and the aqueous phase is extracted four times with ethyl acetate. The combined organic phases are washed with saturated sodium chloride solution, dried over magnesium sulphate and, after filtration, concentrated to dryness under reduced pressure. The residue is chromatographed on silica gel using a gradient of cyclohexane and ethyl acetate. The product-containing fractions are combined and concentrated to dryness under reduced pressure. This gives 20 g (77% of theory) of the desired product.