| 摘要 |
The invention relates to a process for the preparation of 1-alkyl-5-aroyl-1H-pyrrole-2-acetic acid. derivatives of the general formula (I) < IMG > (I) wherein Ar is phenyl optionally substituted with halogen, alkyl having one to 4 carbon atoms or alkoxy having one to 4 carbon atoms; R is alkyl having one to 4 carbon atoms; R1 is hydrogen or alkyl having one to 4 carbon atoms; X is an imino group and R2 is hydrogen or an alkyl group having one to 4 carbon atoms, or X is oxygen and R2 is hydrogen, and acid addition salts (if X=imino) and alkali metal or alkali earth metal salts (if R2=H) thereof, The above compounds are prepared. by reacting a pyrrole derivative of the general formula (II) < IMG > (II) wherein Y stands for a -COOR3 group and. R3 is an alkyl group having one to 4 carbon atoms, with an aromatic nitrile of the general formula Ar-CN wherein Ar is as defined above, in an organic solvent, preferably aromatic hydrocarbon, saturated with dry hydrochloric acid gas and, if desired, hydrolysing a ketimino ester obtained into a corresponding ketimino acid or keto acid or a salt thereof. The process affords the desired products with a good yield, selectively, and, if desired, can be carried out in one pot, without isolating the intermediates. |
