反应详情

4.8 g 5-Hydroxymethyl-2-(4-methoxy-phenyl)-oxazole-4-carboxylic acid ethyl ester were dissolved in 75 ml dichloromethane. 1.9 ml 3,4-dihydro-2H-pyran and 870 mg pyridinium p-toluenesulfonate were added and the reaction mixture stirred at room temperature over night. The solvent was removed in vacuo and the residue purified by flash chromatography on silica gel (eluting with n-heptane:ethyl acetate=3:1=>1:1) to obtain 5.3 g 2-(4-methoxy-phenyl)-5-(tetrahydro-pyran-2-yloxymethyl)-oxazole-4-carboxylic acid ethyl ester.

1. customThe solvent was removed in vacuo
2. customthe residue purified by flash chromatography on silica gel (eluting with n-heptane:ethyl acetate=3:1=>1:1)