Reacción #593050

Ecuación de reacción

1,3-oxazolidine-2,4-dione

1,1,3,3-tetramethylguanidine

1,1-dimethylethyl 4-{[(methylsulphonyl)oxy]methyl}piperidine-1-carboxylate

→

1,1-dimethylethyl 4-[(2,4-dioxo-1,3-oxazolidin-3-yl)methyl]piperidine-1-carboxylate

Disolventes

tetrahydrofuran

dimethylformamide

Condiciones de reacción

Tratamiento posterior

1. 1
   Otroprepared in step 2.1
2. 2
   Temperaturais heated
3. 3
   Temperaturaat reflux for 24 hours
4. 4
   Otroto return to ambient temperature
5. 5
   Concentraciónis concentrated under reduced pressure
6. 6
   Otrowater and the aqueous phase is separated off
7. 7
   Extracciónextracted twice with dichloromethane
8. 8
   LavadoThe combined organic phases are washed with saturated aqueous sodium chloride solution
9. 9
   Secadodried over sodium sulphate
10. 10
    Otroevaporation of the solvent
11. 11
    Otrothe residue obtained
12. 12
    Otrois purified by chromatography on silica gel
13. 13
    Lavadoeluting with a 98/2
14. 14
    workup.ADDITION95/5 mixture of dichloromethane and methanol

Procedimiento

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.

Fuente