Terephthalic Acid → Phthalide

Participants

Reaction Conditions

Reaction Steps

Terephthalic acid was suspended in 25-30% oleum. Trioxane was added and the mixture was heated to 140-150° C. for 4-8 hours. The reaction mixture was cooled and then quenched by cautious addition of water at less than 80° C. The resulting suspension was cooled to about 40° C. and the solid was filtered off. The filter cake was washed with water followed by propan-2-ol before slurrying the solid in propan-2-ol at reflux for 30 minutes. After cooling to 20-25° C. the product was filtered off, washed with propan-2-ol and dried at 60-70° C. under reduced pressure.

Provenance & Evidence