Hydrochloric Acid → HCID 13139571, compound

Participants

Reaction Conditions

Reaction Steps

3-Amino-4-chlorobenzoic acid (34.3g) was added to 5N hydrochloric acid (120 ml) and cooled to 0° C. To the stirred suspension was added a solution of sodium nitrite (14.5 g) in water (35 ml) over 30 min. with the temperature maintained at 0° to 5° C. The yellow diazonium solution, containing some suspended solid was added to a solution of potassium ethyl xanthate (37.5g) in water (60 ml), containing 0.2 g nickel chloride, at 45-50° C. Nitrogen evolution occurred and the yellow solid which precipitated at first decomposed to a red oil which then solidified. When the addition was complete, the mixture was heated to 70° C., cooled, and the red solid filtered off and washed with water. It was then boiled with a solution of potassium hydroxide (60 g) in water (300 ml) for 2 hr., cooled, filtered and acidified with excess hydrochloric acid. Thin-layer chromatography indicated the presence of 2 components in the precipitated creamy solid. Recrystallisation from acetic acid yielded a by-product, m.p. 240°-290° C., and dilution of the recrystallisation liquors gave a solid which was recrystallised from aqueous ethanol yielding mainly 4-chloro-3-mercaptobenzoic acid, m.p. 200°-211° C.

Provenance & Evidence