Acetic Acid → 2,3-Dichloro-N-methylmaleimide

Participants

Reaction Conditions

Reaction Steps

A 3L-three-necked flask fitted with a magnetic stir bar, digital thermocouple/thermometer, nitrogen purge and solid addition funnel was charged with 450 g (269.5 mol) of dichloromaleic anhydride, 191 g (282.8 mol) of methylamine hydrochloride and 1.6 L of acetic acid. The reaction mixture was then cooled to 10° C., and 160 g NaOMe added from the solid addition funnel over 1 hour while keeping the temperature between 10°-12° C. The reaction mixture was allowed to stir at room temperature for 42 hours (24 hours is sufficient) then heated to 100° C. for 3 hours. HPLC analysis at this time indicated that all the starting material had disappeared. The reaction was cooled to room temperature and 2L water was added. The mixture was then cooled to 3°-10° C. for 1 hour and filtered at 4° C. The solids were then rinsed with 2L of cold deionized water. The pale yellow solid dried in an air oven overnight to afford 360 g (75%) yield of the titled compound.

Provenance & Evidence