反应详情

A mixture of benzyl 3-(1-methylcyclohexylcarbonylamino)-4-oxovalerate (1.2 g), toluene (20 ml) and phosphorus oxychloride (2.0 ml) was refluxed with stirring for 4 hours. The solvent was distilled off and aqueous sodium hydrogen carbonate was added. The mixture was extracted with ethyl ether and the ethyl ether layer was washed with water and dried over anhydrous magnesium sulfate. The solvent was then distilled off and the residue was purified by chromatography on silica gel (13 g) [eluent: hexaneacetone (9:1)] to give benzyl 5-methyl-2-(1-methylcyclohexyl)- 4-oxazoleacetate; yield 1.0 g (87.7%).

1. temperaturewas refluxed
2. distillationThe solvent was distilled off
3. additionaqueous sodium hydrogen carbonate was added
4. extractionThe mixture was extracted with ethyl ether
5. washthe ethyl ether layer was washed with water
6. dry with materialdried over anhydrous magnesium sulfate
7. distillationThe solvent was then distilled off
8. customthe residue was purified by chromatography on silica gel (13 g) [eluent: hexaneacetone (9:1)]