| 摘要 |
PURPOSE:To prepare the titled compound useful as an intermediate of pharmaceuticals, agricultural chemicals, etc., easily, in high yield, under mild conditions, by reacting a vinylsulfone compound with an isocyanoacetic acid ester. CONSTITUTION:The objective compound of formula III can be prepared by reacting a vinylsulfone of formulaI[R1 is H, alkyl, (substituted) phenyl, or heterocyclic group; R2 is alkyl or aryl]with an isocyanoacetic acid ester of formula II (R3 is alkyl or aralkyl) in an organic solvent in the presence of a base such as NaH or a catalyst such as cuprous oxide, at room temperature or under heating or cooling. The organic solvent is a non-aqueous solvent such as benzene, tetrahydrofuran, etc. When the reaction is carried out in the presence of a base, it is preferable to add dimethylsulfoxide (DMSO) or dimethyl formamide (DMHA) in an amount equivalent to the compound of formula II or to use an anionically stabilized solvent such as DMSO, DMHA, etc. |
