Hydrochloric Acid → 4-Chlorophthalic anhydride

Participants

Reaction Conditions

Reaction Steps

A 3-necked 50 mL flask was equipped with a pressure equalizing addition funnel, a thermocouple well with thermocouple, a water cooled condensor and a magnetic stir bar. The flask was charged with 13.2 g (0.10 mol) of a 90/10 GC area % mixture of monochloromaleic anhydride and dichloromaleic anhydride and 100 mg of phenothiazine and 0.5 g of activated carbon. The contents of the flask were heated to 80 to 130° C. and 8.8 g (0.1 mol) of chloroprene was added over 15 to 30 minutes. HCl gas was observed evolving from the reactor. After 6 hours at 130° C. the contents of the flask were sparged with oxygen for 2 hours between 130° and 150° C., filtered hot, and multiple distilled into two fractions resulting in the isolation of 13.2 g (80% of theoretical) of 4-chlorophthalic anhydride.

Provenance & Evidence