反应详情

温度

-78 °C

0.93 g (7.31 mmol) of oxalyl chloride is dissolved in 50 ml of dichloromethane and cooled to −78° C., and 1.14 g (14.63 mmol) of dimethyl sulfoxide are added slowly. A solution of 1.49 g (4.88 mmol) of the compound from Example 10A (incl. subsequent syntheses), dissolved in 10 ml of dichloromethane, is then added. The reaction mixture is stirred at −78° C. for 1 h. 3.4 ml (24.38 mmol) of triethylamine are then added slowly, and the mixture is warmed to RT over a period of 1 h. 50 ml of ethyl acetate and 30 ml of sodium bicarbonate solution are then added to the mixture. The phases are separated, and the aqueous phase is extracted twice with in each case 20 ml of ethyl acetate. The combined organic phases are dried over magnesium sulfate. The solvent is removed on a rotary evaporator and the residue is purified chromatographically on silica gel 60 (mobile phase: gradient cyclohexane/ethyl acetate 50:1→10:1).

1. additionis then added
2. temperaturethe mixture is warmed to RT over a period of 1 h
3. customThe phases are separated
4. extractionthe aqueous phase is extracted twice with in each case 20 ml of ethyl acetate
5. dry with materialThe combined organic phases are dried over magnesium sulfate
6. customThe solvent is removed on a rotary evaporator
7. customthe residue is purified chromatographically on silica gel 60 (mobile phase: gradient cyclohexane/ethyl acetate 50:1→10:1)