反应详情

A mixture of methyl 3-benzyloxy-5-(methylsulfonyl)-2-thiophenecarboxylate (16.7 g, 51.2 mmol), 50 ml 2N NaOH and 50 ml of tetrahydrofuran is heated at reflux temperatures for 1 hour, cooled to room temperature and concentrated in vacuo to an aqueous residue. The residue is diluted with water, acidified to pH 1-2 with 6N HCl and filtered. The filtercake is washed with water and dried to give the title product as a white solid, 14.55 g (91% yield). A small sample was recrystallized from aqueous ethanol to give white needles, mp 188-189° C., identified by 1HNMR, 13CNMR, IR and mass spectral analyses.

1. temperatureis heated
2. temperatureat reflux temperatures for 1 hour
3. concentrationconcentrated in vacuo to an aqueous residue
4. additionThe residue is diluted with water
5. filtrationfiltered
6. washThe filtercake is washed with water
7. customdried