| 摘要 |
PURPOSE:To provide a method for producing a maleinamic acid ester from a maleinamic acid and an alcohol simply, in a high yield and with a high selectivity. CONSTITUTION:Maleinamic acid of formula I is reacted with >=5mol equivalent based on the compound of an alcohol of the formula R<1>-OH (R<1> is a 1-8C alkyl or a 3-8C cycloalkyl) in an inert solvent in the presence of a sulfonic acid-based derivative at 10-100 deg.C, preferably 20-70 deg.C to give a maleinamic acid ester of the formula II. An inert solvent forming an azeotropic mixture with the alcohol is used as the inert solvent. The amount of the solvent used is >=0.1mol equivalent, preferably 0.3-13mol equivalent based on maleinamic acid and <=3mol equivalent, preferably 0.05-2mol equivalent based on the alcohol. Sulfuric acid, sulfuric anhydride, an arylsulfonic acid, an alkylsulfonic acid, a mono(dichloro) alkylsulfuric ester or an acidic ion exchange resin is used as the sulfonic acid- based catalyst and the amount of the catalyst used is 0.01-2mol, preferably 0.1-1mol based on the starting raw material. |
