Hydrochloric Acid → 5-Anilino-3,4-dimethoxy-2H-pyrrol-2-one

Participants

Reaction Steps

12 parts by weight of 2-phenyl-4,5-dimethoxypyridazin-3-one were suspended in 150 parts by volume of dimethyl sulfoxide, and 9 parts by weight of a 30% strength solution of sodium methylate in methanol were added dropwise. The mixture was stirred for 20 hours at room temperature, after which it was stirred into 1 liter of ice water and rendered neutral by adding concentrated hydrochloric acid, and the product was filtered off under suction. 11.4 parts by weight of 2,5-dihydro-3,4-dimethoxy-5-phenyliminopyrrol-2-one of melting point 141°-143° C. were obtained (compound No.1).

Provenance & Evidence