反应详情

5.39 g (35.7 mmol) of tert-butyldimethylsilyl chloride and 3.30 g (48.5 mmol) of imidazole are added successively to a solution of 4.60 g (25.5 mmol) of the compound from Example 40A in 120 ml of dry dimethylformamide, and the mixture is stirred at RT for 20 h. 100 ml of saturated sodium bicarbonate solution are then added, and the reaction mixture is extracted with diethyl ether (three times, 100 ml each). The combined organic phases are dried over magnesium sulphate. After removal of the solvent on a rotary evaporator, the crude product is purified chromatographically on silica gel 60 (mobile phase gradient cyclohexane/ethyl acetate 50:1→10:1).

1. extractionthe reaction mixture is extracted with diethyl ether (three times, 100 ml each)
2. dry with materialThe combined organic phases are dried over magnesium sulphate
3. customAfter removal of the solvent
4. customon a rotary evaporator
5. customthe crude product is purified chromatographically on silica gel 60 (mobile phase gradient cyclohexane/ethyl acetate 50:1→10:1)