Maleic Anhydride → Phthalic Acid

Participants

Reaction Steps

84.5 g (0.4 mol) of 4-nitrophthalic acid are hydrogenated in 720 ml of dioxane, in the presence of 4 g of a palladium/charcoal catalyst containing 5% by weight of palladium, at 25° C. 47.02 g (0.48 mol) of maleic anhydride are added to the filtered reaction solution. After a reaction time of 12 hours, the 4-(maleinamidyl)-phthalic acid which has precipitated is filtered off and washed with 50 ml of dioxane. After drying at 80° C./15 mm Hg for 12 hours, 101.6 g (91% of theory) of 4-maleinamidyl)-phthalic acid are obtained.

Provenance & Evidence