反应详情

A solution of 1.34 g. of 5-benzoyl-7-bromo-1,2-dihydro-3H-pyrrolo[1,2-a]pyrrole-1-carboxylic acid in 50 ml. of isopropanol, cooled in an ice bath is saturated with gaseous hydrogen chloride, maintaining the temperature of the reaction mixture below 50° C. The ice bath is then removed and the reaction mixture is stirred for 1.5 hours at room temperature, and evaporated to dryness under reduced pressure; 10 ml. of benzene is added to the residue and the solution is evaporated under vacuum once again, repeating this process a total of three times to completely remove the excess hydrogen chloride, thus obtaining of isopropyl 5-benzoyl-7-bromo-1,2-dihydro-3H-pyrrolo[1,2-a]pyrrole-1-carboxylate. The product is recrystallized from methanol-ethyl acetate.

1. temperaturemaintaining the temperature of the reaction mixture below 50° C
2. customThe ice bath is then removed
3. customevaporated to dryness under reduced pressure
4. additionof benzene is added to the residue
5. customthe solution is evaporated under vacuum once again
6. customto completely remove the excess hydrogen chloride