反应详情

温度

60 °C

The crude product of the compound from Example II is dissolved in 1.5 l of 95% ethanol and warmed to 60° C. A solution of 186 g (1.1 mol) of silver nitrate in 380 ml of water which has been mixed with 750 ml of ethanol is rapidly added dropwise thereto at this temperature. After addition is complete, the mixture is subsequently stirred for one hour and then mixed with 50 ml of saturated sodium chloride solution. After cooling, the silver salts are filtered off and the filtrate is concentrated. The residue is taken up in methylene chloride and purified by filtration through a short silica gel column (eluent: dichloromethane). After concentrating the product fractions, 88 g (81%) of the title compound are obtained.

1. additionis rapidly added dropwise
2. additionAfter addition
3. temperatureAfter cooling
4. filtrationthe silver salts are filtered off
5. concentrationthe filtrate is concentrated
6. filtrationpurified by filtration through a short silica gel column (eluent: dichloromethane)
7. concentrationAfter concentrating the product fractions, 88 g (81%) of the title compound
8. customare obtained