Hydrochloric Acid → 1-methyl-1H-pyrrole-3-carboxylic acid

Participants

Reaction Steps

A mixture of Compound 1 (7.66 g, 50 mmole), which had been obtained in Preparation Example 1, and a 2 N aqueous solution of sodium hydroxide (37.5 ml, 75 mmole) was refluxed for 2 hours. The reaction mixture was cooled to 0° C., to which 6 N hydrochloric acid was added under stirring to acidify the same. Sodium chloride (15 g) was then added, followed by stirring for 1 hour over an ice-acetone bath. Precipitated crystals were collected. Those crystals were washed with chilled water and then dried under reduced pressure, whereby the title compound (5.77 g) was obtained (yield: 92.2%).

Provenance & Evidence