Hydrochloric Acid → HCID 18424343, compound

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Reaction Steps

A solution of 4.13 g. (0.0131 mole) of ethyl 5-benzoyl-3-carboxy-4-methyl-pyrrole-2-acetate in 80 ml. of quinoline in the presence of a trace amount of copper chromite is heated at 180-183° C. for 5 hours. The mixture is poured into dilute hydrochloric acid and extracted three times with ether. The ether extracts are combined and washed successively with dilute hydrochloric acid, sodium bicarbonate solution and brine and then dried over anhydrous magnesium sulfate. The solvent is evaporated in vacuo to give about 4 g. of semisolid ethyl 5-benzoyl-4-methylpyrrole-2-acetate which is used in the following hydrolysis procedure without further purification. The entire semisolid is dissolved in 20 ml. of ethanol and 20 ml. of 1N sodium hydroxide solution is added. The mixture is heated under reflux for 30 minutes. The solvent is then evaporated in vacuo, and the residue dissolved in water and washed with ether. The aqueous solution is acidified with dilute hydrochloric acid and the resulting crystalline solid (1.6 g., 50% yield) is collected by filtration and air-dried. The product, 5-benzoyl-4-methylpyrrole-2-acetic acid is recrystallized three times from acetone-water with charcoaling, m.p. 167-168° C.

Provenance & Evidence