Process for the preparation of 3-(substituted phenyl)-5-alkylidene-1,3-oxazolidine-2,4-dione derivatives

摘要

PCT No. PCT/JP96/00430 Sec. 371 Date Dec. 15, 1997 Sec. 102(e) Date Dec. 15, 1997 PCT Filed Feb. 26, 1996 PCT Pub. No. WO96/26930 PCT Pub. Date Sep. 6, 1996The 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): (wherein Ar is a substituted phenyl group, R1 is an alkyl group having a carbon number of from 1 to 6, R2 and R3 are independently hydrogen atoms or alkyl groups having carbon numbers of from 1 to 12, and R4 and R5 are independently alkyl groups having carbon numbers of from 1 to 6).