PROCESS FOR THE PREPARATION OF 3-(SUBSTITUTED PHENYL)-5-ALKYLIDENE-1,3-OXAZOLIDINE-2,4-DIONE DERIVATIVES

摘要

The present invention provides an industrial process for efficiently preparing a 3-(substituted phenyl)-5-isopropylidene-1,3-oxazolidine-2,4-dione derivative having a potent herbicidal activity without using phosgene or the like. The present invention relates to a process for preparing a 3-(substituted phenyl)-5-alkylidene-1,3-oxazolidine-2,4-dione derivative represented by general formula (III), which comprises reaction of an N-(substituted phenyl)carbamate represented by general formula (I) with a 2-hydroxy-3-alkenoate represented by general formula (II) or with a 3-alkoxy-2-hydroxyalkanoate represented by general formula (IV): <CHEM> (wherein Ar is a substituted phenyl group, R<1> is an alkyl group having a carbon number of from 1 to 6, R<2> and R<3> are independently hydrogen atoms or alkyl groups having carbon numbers of from 1 to 12, and R<4> and R<5> are independently alkyl groups having carbon numbers of from 1 to 6).