Hydrochloric Acid → Phthalic Acid

Participants

Reaction Conditions

Reaction Steps

A 2 L, round-bottomed, 3-necked flask was charged with 830 g of 50% aqueous potassium hydroxide solution, and 333 g of 2-chlorobenzylphthalimide. The reaction mixture was then heated under reflux (pot temperature 125-128° C.) for 21 hours with stirring. It was then cooled in iced-water and allowed to settle in a separating funnel. The lower aqueous layer was drained, diluted with 2 L of water and acidified with 676 g of concentrated hydrochloric acid (with cooling). This caused the formation of a white precipitate, which was collected by filtration and dried in a vacuum oven overnight to yield 199.9 g of phthalic acid (98%). The organic layer was essentially pure (99.9% by GC) 2-chlorobenzylamine (163.4 g, 1.15 mol, 93.5%).

Provenance & Evidence