Maleic Anhydride → 2,5-Dioxo-2,5-dihydrofuran-3-sulfonic acid

Participants

Reaction Conditions

Reaction Steps

The reagent was prepared using the sulfonation procedure of U.S. Pat. No. 3,987,043 (cited previously). Liquid sulfur trioxide (100 mole %) was added slowly to the agitated maleic anhydride powder while heating to maintain the temperature at 60° C. After the exothermic reaction was complete, the reaction temperature was raised to 100°-110° C. and the mixture was held for 3 hours. After cooling to room temperature, the viscous dark brown oil crystallized to solid sulfomaleic anhydride.

Provenance & Evidence