[CH3:1][C:2]1[O:6][CH:5]=[C:4]([C:7]([O:9]CC)=[O:8])[CH:3]=1.[OH-].[K+].Cl>O>[CH3:1][C:2]1[O:6][CH:5]=[C:4]([C:7]([OH:9])=[O:8])[CH:3]=1A mixture of 31.7 g (206 mmol) of ethyl 5-methylfuran-3-carboxylate, 40 ml of 45% strength potassium hydroxide and 100 ml of water was refluxed for 4 h, then cooled to 10° C. and acidified to pH 1 with 15% strength hydrochloric acid. The resulting mixture was left at this temperature for 2 h, and the precipitate was filtered off and dried to constant weight at 45-50° C., resulting in 23.7 g (188 mmol, 91%) of 5-methylfuran-3-carboxylic acid.
Wird geladen…