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

Temperature

10 °C

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.

1. customA 3L-three-necked flask fitted with a magnetic stir bar
2. customdigital thermocouple/thermometer, nitrogen purge
3. additionsolid addition funnel
4. custombetween 10-12° C
5. temperaturethen heated to 100° C. for 3 hours
6. temperatureThe reaction was cooled to room temperature
7. temperatureThe mixture was then cooled to 3-10° C. for 1 hour
8. filtrationfiltered at 4° C
9. washThe solids were then rinsed with 2 L
10. customThe pale yellow solid dried in an air oven overnight

ORD record

ord-649fa3f6f2fe4238a9450b19fa5e0632

Source dataset

uspto-grants-1999_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05919946