PREPARATION OF 5-AMINO 1,2,4-TRIAZOLE-3-SULFONAMIDES AND INTERMEDIAT ES

摘要

A process for preparing 5-amino-1,2,4-triazole-3-sulfonamides of formula I, which are intermediates for substituted 1,2,4-triazolo¢1,5-a!-pyrimidine-2-sulfonamide herbicides, in two steps from 5-amino-3-mercapto-1,2,4-triazole by chlorination in a medium containing an aqueous acid to obtain 5-amino-3-chlorosulfonyl-1,2,4-triazole and subsequent condensation of this intermediate with substituted anilines is disclosed. The condensation reaction takes place either in the presence or absence of an acid scavenging base. Novel intermediates are also provided. The process may be represented by the following reaction sequence: (see fig. I) + (see fig. II) (see fig. III)