| abstract |
PCT No. PCT/US93/10435 Sec. 371 Date May 9, 1995 Sec. 102(e) Date May 9, 1995 PCT Filed Nov. 5, 1993 PCT Pub. No. WO94/11359 PCT Pub. Date May 26, 1994Processes are described for preparing 2,4-oxazolidinediones having Formula (I) <IMAGE> (I) wherein: R1 is phenyl optionally substituted with 1-2 halogens; or 4-phenoxy, 4-(1-phenethyloxy) or 4-benzyloxy each optionally substituted with R2 on the phenyl ring; and R2 is halogen; methyl; or ethyl. 2-Hydroxycarboxylic acid esters are reacted with a carbonylating agent in the presence of a base to give intermediate triazole or imidazole carboxylates. The carboxylates react with phenyl hydrazine in the presence of an acid to give the compounds of Formula (I). |