反应详情

A suspension of 13.60 g (46.36 mmol) of 1,1-dimethylethyl 4-{[(methylsulphonyl)oxy]methyl}piperidine-1-carboxylate, prepared in step 2.1., 9.37 g (92.72 mmol) of 1,3-oxazolidine-2,4-dione and 16.02 g (139.08 mmol) of 1,1,3,3-tetramethylguanidine in a mixture of 180 ml of tetrahydrofuran and 30 ml of dimethylformamide is heated at reflux for 24 hours. It is allowed to return to ambient temperature and is concentrated under reduced pressure. The residue is taken up in dichloromethane and water and the aqueous phase is separated off and extracted twice with dichloromethane. The combined organic phases are washed with saturated aqueous sodium chloride solution and dried over sodium sulphate. Following evaporation of the solvent, the residue obtained is purified by chromatography on silica gel, eluting with a 98/2 then 95/5 mixture of dichloromethane and methanol.

1. customprepared in step 2.1
2. temperatureis heated
3. temperatureat reflux for 24 hours
4. customto return to ambient temperature
5. concentrationis concentrated under reduced pressure
6. customwater and the aqueous phase is separated off
7. extractionextracted twice with dichloromethane
8. washThe combined organic phases are washed with saturated aqueous sodium chloride solution
9. dry with materialdried over sodium sulphate
10. customevaporation of the solvent
11. customthe residue obtained
12. customis purified by chromatography on silica gel
13. washeluting with a 98/2
14. addition95/5 mixture of dichloromethane and methanol