反应详情

A solution of 50 g of 3,4,5-trimethoxybenzoic acid in 500 ml dry methanol containing 4.8 ml of conc. sulfuric acid was refluxed under anhydrous condition for 18 hr and concentrated to half the volume. The solution was poured into ice water and extracted with methylene chloride. The organic extract was washed with cold 0.5 N sodium hydroxide and water, dried over sodium sulfate, evaporated and crystallized from hexane to give 3,4,5-trimethoxybenzoic acid methyl ester, mp 65°-66° C.

1. concentrationconcentrated to half the volume
2. additionThe solution was poured into ice water
3. extractionextracted with methylene chloride
4. extractionThe organic extract
5. washwas washed with cold 0.5 N sodium hydroxide and water
6. dry with materialdried over sodium sulfate
7. customevaporated
8. customcrystallized from hexane