反应详情

温度

0 °C

7.00 g (25.0 mmol) methyl 4-(3-[1,1-dimethyl-2-hydroxy-ethyl]-ureido)-3-methyl-benzoate are dissolved in 400 ml THF at 0° C. and combined with 6.73 g (60.0 mmol) potassium-tert.-butoxide. After stirring for 15 minutes at 0° C. a solution of 5.72 g (30.0 mmol) p-toluenesulphonic acid in 50 ml THF is added dropwise. After another 10 minutes stirring at 0° C. 300 ml of water are added, the mixture is neutralised with 1-molar hydrochloric acid and the THF is removed i. vac. The residue is extracted with dichloromethane. The combined organic phases are dried over sodium sulphate and evaporated down i. vac. Then the residue is purified by chromatography on silica gel (eluting gradient: dichloromethane/ethanol=100:0->97:3).

1. additionis added dropwise
2. customthe THF is removed i
3. extractionThe residue is extracted with dichloromethane
4. dry with materialThe combined organic phases are dried over sodium sulphate
5. customevaporated down i
6. customThen the residue is purified by chromatography on silica gel (eluting gradient: dichloromethane/ethanol=100:0->97:3)