反应详情

To a solution of glyoxylic acid ethyl ester (50% w/w in toluene) (4 mL, 2 mmol) and Tosmic (3.86 g, 2 mmol) in MeOH (60 mL) was added K2CO3 (5.6 g, 4 mmol) and the mixture was stirred at reflux for 7 h. The solvent was then evaporated and 100 mL of water was added. This solution was saturated with sodium chloride and extracted with diethyl ether. The organic layer was washed with brine, dried (MgSO4) filtered and concentrated to give 1.58 g (60%) of oxazole-5-carboxylic acid methyl ester as white solid. m.p.=35-50° C.

1. temperatureat reflux for 7 h
2. customThe solvent was then evaporated
3. addition100 mL of water was added
4. extractionextracted with diethyl ether
5. washThe organic layer was washed with brine
6. dry with materialdried (MgSO4)
7. filtrationfiltered
8. concentrationconcentrated