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 2 L 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 2 L 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