反应详情

A solution of the benzylidenerhodanine of Example 7 in 18 ml. of 15% NaOH is refluxed for 0.75 hour and poured into dilute HCl, whereupon a yellow solid forms. The solid is collected and recrystallized from ethanol to give 7-methoxy-1-oxo-1H-2-benzothiopyran-3-carboxylic acid as pale yellow needles, m.p. 291°-292°.

1. customThe solid is collected
2. customrecrystallized from ethanol