反应详情

温度

0 °C

20 g (0.37 mol) sodium methoxide are suspended in 50 mL dimethylformamide, a suspension of 21 g (0.1 mol) N-(7-oxo-4,5,6,7-tetrahydro-benzothiazol-2-yl)-acetamide in 100 mL dimethylformamide is added dropwise. The mixture is stirred for 15 minutes, then cooled to 0° C. A mixture of 29.9 mL (0.37 mol) ethyl formate and 60 mL benzene is added dropwise and the reaction mixture is diluted with another 100 mL benzene. A precipitate gradually settles out and stirring is continued at 0° C. for 3.5 hours. The suspension is hydrolysed with 370 mL 1 molar hydrochloric acid, the solid precipitated is suction filtered. The two phases of the mother liquor are separated, the aqueous phase is extracted with dichloromethane. The resulting organic phase is dried and evaporated to dryness. The solid and the residue from the extraction are recrystallised from acetonitrile. Yield: 20 g

1. additionis added dropwise
2. additionis added dropwise
3. stirringstirring
4. waitis continued at 0° C. for 3.5 hours
5. customthe solid precipitated
6. filtrationfiltered
7. customThe two phases of the mother liquor are separated
8. extractionthe aqueous phase is extracted with dichloromethane
9. customThe resulting organic phase is dried
10. customevaporated to dryness
11. extractionThe solid and the residue from the extraction
12. customare recrystallised from acetonitrile