Sulfuric Acid → 4-Chloroquinoline-7-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

Commercially available 4-chloro-7-(trifluoromethyl)-quinoline (8 g, 0.035 mol) was added under ice cooling with 30% fuming sulfuric acid (35 ml) and stirred at 100° C. for 5 hours. After allowing to cool to room temperature, the reactant was poured into ice water and made basic enough with excess concentrated ammonia water, and insoluble materials were filtered off. The filtrate was adjusted by 2N hydrochloric acid to pH 3-4. The resulting jellied precipitate was collected by filtration, washed with ethanol (50 ml) and dried under reduced pressure over phosphorus pentoxide to obtain 5.4 g (74%) of 7-carboxy-4-chloroquinoline.

Provenance & Evidence