反应详情

With ice-cooling, a solution of 902 mg (7.40 mmol) of 9-borabicyclo[3.3.1]nonane in 14.8 ml tetrahydrofuran is added to 800 mg (2.96 mmol) of the compound from Example 52A. The mixture is stirred at room temperature for 3 h and then cooled to 0° C., and an aqueous solution of 591 mg (14.8 mmol) of sodium hydroxide is added over a period of 15 min. 2.60 ml of a 30% strength hydrogen peroxide solution are added such that the temperature does not exceed 30° C. After the addition has ended, the mixture is stirred at 0° C. for 30 min. With ice-cooling, a solution of 8.73 g (32.6 mol) of sodium bisulphite in 12 ml of water is added to the reaction mixture. The mixture is diluted with 50 ml of ethyl acetate, the organic phase is removed and the aqueous phase is extracted twice with ethyl acetate. The combined organic phases are washed with saturated sodium chloride solution, dried over sodium sulphate and evaporated to dryness under reduced pressure. The residue is purified by chromatography on silica gel (cyclohexane/ethyl acetate 1:2). This gives 765 mg (89% of theory) of the desired product.

1. temperatureWith ice-cooling
2. temperaturecooled to 0° C.
3. customdoes not exceed 30° C
4. additionAfter the addition
5. stirringthe mixture is stirred at 0° C. for 30 min
6. temperatureWith ice-cooling
7. customthe organic phase is removed
8. extractionthe aqueous phase is extracted twice with ethyl acetate
9. washThe combined organic phases are washed with saturated sodium chloride solution
10. dry with materialdried over sodium sulphate
11. customevaporated to dryness under reduced pressure
12. customThe residue is purified by chromatography on silica gel (cyclohexane/ethyl acetate 1:2)