5-(p-Chlorobenzoyl)-3-hydroxycarbonyl-4-methoxy-1-methylpyrrole-2-acetic acid → [5-(4-Chlorobenzoyl)-4-methoxy-1-methyl-1H-pyrrol-2-yl]acetic acid
Reaction equation
[Cl:1][C:2]1[CH:24]=[CH:23][C:5]([C:6]([C:8]2[N:12]([CH3:13])[C:11]([CH2:14][C:15]([OH:17])=[O:16])=[C:10](C(O)=O)[C:9]=2[O:21][CH3:22])=[O:7])=[CH:4][CH:3]=1>FC(F)(F)C(O)=O>[Cl:1][C:2]1[CH:3]=[CH:4][C:5]([C:6]([C:8]2[N:12]([CH3:13])[C:11]([CH2:14][C:15]([OH:17])=[O:16])=[CH:10][C:9]=2[O:21][CH3:22])=[O:7])=[CH:23][CH:24]=1Participants
3
Procedure
5-(p-Chlorobenzoyl)-3-hydroxycarbonyl-4-methoxy-1-methylpyrrole-2-acetic acid (prepared from Example 1, Step E) is dissolved in 5 ml of trifluoroacetic acid (TFA) and heated to reflux under nitrogen. After about 45 minutes the reaction is substantially complete. It is cooled and concentrated in vacuo. The resultant residue is treated with 10 ml of water, and the precipitate is filtered, and dried to afford 925 mg (81.5%) of 5-(p-chlorobenzoyl)-4-methoxy-1-methylpyrrole-2-acetic acid, m.p. 142°.