反应详情

温度

105 °C

20.2 g (0.1 mole) of compound (47), 1.5 g (0.05 mole) paraformaldehyde and 4.07 g (0.05 mole) dimethylamine hydrochloride were dissolved in 40 ml acetic acid and heated in a bath at 105° C. for 20 minutes with stirring. The acetic acid was subsequently distilled off under vacuum, and the residue was dissolved in 100 ml water and extracted with ether. The aqueous phase was adjusted to a pH of 11 with aqueous sodium hydroxide solution and the Mannich base was extracted with dichloromethane. After drying and removal of the solvent by distillation, 17.5 g of the base of compound (47) were obtained, and were taken up in 2-butanone. 17.2 g of compound (48) were obtained in a yield of 58% theoretical by the subsequent addition of trimethylchlorosilane/water.

1. distillationThe acetic acid was subsequently distilled off under vacuum
2. dissolutionthe residue was dissolved in 100 ml water
3. extractionextracted with ether
4. extractionthe Mannich base was extracted with dichloromethane
5. customAfter drying
6. customremoval of the solvent
7. distillationby distillation, 17.5 g of the base of compound (47)
8. customwere obtained