N-pyrazolyl-1,2,4-triazolo[1,5-c]pyrimidine-2-sulfonamide herbicides

摘要

N-(3-, 4-, and 5-)-pyrazolyl-1,2,4-triazoloÄ1,5-cÜpyrimidine-2-sulfonamide compounds of formula (I), substituted on the pyrimidine ring with an alkoxy group and on the pyrazine ring, such as N-(4-bromo-1-methylpyrazol-3-yl)-7-chloro-5-methoxy-1,2,4-triazoloÄ1,5 -cÜpyrimidine-2- sulfonamide, were prepared from alkoxy substituted 1,2,4-triazoloÄ1,5-cÜ pyrimidine-2-sulfonyl halides by condensation with substituted (3-, 4-, and 5-aminopyrazoles in the presence of a pyridine base and a catalytic amount of dimethyl sulfoxide. The compounds were found to possess general and, in some cases, selective pre- and postemergence herbicidal activity.