Reacción #657278

Ecuación de reacción

4-benzyloxy-8-methoxy-1-methyl-3-(2,4,6-trimethyl-phenyl)-1,8-diaza-spiro[4.5]dec-3-en-2-one

→

4-hydroxy-8-methoxy-1-methyl-3-(2,4,6-trimethyl-phenyl)-1,8-diaza-spiro[4.5]dec-3-en-2-one

Disolventes

methanol

water

Condiciones de reacción

Tratamiento posterior

1. 1
   Filtraciónthe reaction mixture was filtered
2. 2
   Concentraciónconcentrated
3. 3
   workup.ADDITIONThe residue was diluted with ethyl acetate
4. 4
   Extracciónextracted with saturated aqueous sodium carbonate under ice cooling
5. 5
   Temperaturawith cooling to pH 5-6 with an aqueous HCl solution
6. 6
   Extracciónthoroughly extracted with ethyl acetate
7. 7
   LavadoThe combined organic layers were washed with brine
8. 8
   Secadodried over sodium sulfate
9. 9
   Concentraciónconcentrated

Procedimiento

To a solution of 4-benzyloxy-8-methoxy-1-methyl-3-(2,4,6-trimethyl-phenyl)-1,8-diaza-spiro[4.5]dec-3-en-2-one (22.6 g, 53.7 mmol) in methanol (226 ml) and water (22.6 ml) in a Parr shaker type hydrogenator was added 5% Pd/C (22.6 g). After hydrogenation under 4 bars H2 at 36° C. for 22 hours, the reaction mixture was filtered and concentrated. The residue was diluted with ethyl acetate and extracted with saturated aqueous sodium carbonate under ice cooling. The organic layer was discarded, the aqueous alkaline phase acidified with cooling to pH 5-6 with an aqueous HCl solution and thoroughly extracted with ethyl acetate. The combined organic layers were washed with brine, dried over sodium sulfate and concentrated. Yield: 13.0 g of 4-hydroxy-8-methoxy-1-methyl-3-(2,4,6-trimethyl-phenyl)-1,8-diaza-spiro[4.5]dec-3-en-2-one (title compound P2.2) as a solid, mp 239-241° C.

Fuente