反应详情

To a solution of 1,1-dimethylethyl 6-(5-{3-chloro-4-[(1-methylethyl)oxy]phenyl}-1,2,4-oxadiazol-3-yl)-1-[4-(ethyloxy)-4-oxobutyl]-5-methyl-3,4-dihydro-2(1H)-isoquinolinecarboxylate (Preparation 28; 110 mg, 0.184 mmol) in ethanol (3 ml) was added 2M aqueous sodium hydroxide (0.184 ml, 0.368 mmol) and the resulting mixture was stirred at room temperature for 100 min. More 2M aqueous sodium hydroxide (0.1 ml) was added and stirring continued at room temperature for 5.5 h. Most of the solvent was removed, and the residue partitioned between ether and water. Aqueous 2M sodium hydroxide was added to make sure the phase was basic, causing precipitation of the carboxylate. The aqueous layer was acidified with 2N aqueous hydrochloric acid, and extracted twice with ethyl acetate. The ethyl acetate layer was dried over MgSO4 and concentrated in vacuo to give the title compound (95 mg) as a white foam.

1. stirringstirring
2. waitcontinued at room temperature for 5.5 h
3. customMost of the solvent was removed
4. customthe residue partitioned between ether and water
5. additionAqueous 2M sodium hydroxide was added
6. customprecipitation of the carboxylate
7. extractionextracted twice with ethyl acetate
8. dry with materialThe ethyl acetate layer was dried over MgSO4
9. concentrationconcentrated in vacuo