反应详情

To a solution of 4-formyl-1H-pyrrole-2-carboxylic acid methyl ester (589 mg) in acetone/water (50 mL, 1:1) was added a solution of KMnO4 in acetone/water (70 mL, 1:1) dropwise within one hour. The mixture was stirred for 3 h at RT whereupon it was poured into a solution of NaHSO3 (10% in 1 N HCl, 100 mL). The resulting mixture was extracted with ethyl acetate. The combined organic phases were washed with water and extracted with 2N aqueous K2CO3 solution. The basic aqueous phase was acidified with 2N HCl and extracted with ethyl acetate The combined organic phases were dried (MgSO4) and concentrated in vacuo to provide 1H-pyrrole-2,4-dicarboxylic acid 2-methyl ester (530 mg) which was used directly in the next step.

1. extractionThe resulting mixture was extracted with ethyl acetate
2. washThe combined organic phases were washed with water
3. extractionextracted with 2N aqueous K2CO3 solution
4. extractionextracted with ethyl acetate The combined organic phases
5. dry with materialwere dried (MgSO4)
6. concentrationconcentrated in vacuo