[CH3:1][N:2]1[C:6]([CH3:7])=[C:5](C(O)=O)[C:4]([C:11]2[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=2)=[C:3]1C(O)=O.NCCO>O>[CH3:1][N:2]1[CH:3]=[C:4]([C:11]2[CH:12]=[CH:13][CH:14]=[CH:15][CH:16]=2)[CH:5]=[C:6]1[CH3:7]A suspension of 1,5-dimethyl-3-phenyl-pyrrole-2,4-dicarboxylic acid (60 g, 0.23 mol) and 2-aminoethanol (300 mL) was heated to 175° C. under a nitrogen atmosphere for 30 min. The mixture was allowed to cool to room temperature, diluted with water (100 mL) and extracted with ethyl acetate (2×100 mL). The combined organic layers were washed successively with water (3×100 mL) and brine (2×100 mL), dried over anhydrous sodium sulfate and concentrated in vacuo at a temperature below 40° C. to afford the crude product. Flash column chromatography over neutral alumina using 5% ethyl acetate in petroleum ether as eluent afforded 1,2-dimethyl-4-phenyl-pyrrole (30.5 g, 78%) as a white solid.
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