N-(Triazoloazinyl)arylsulfonamide compounds, such as 2,6-dimethoxy-N-(8-chloro-5-methoxy[1,2,4]triazolo[1,5-c]pyrimidin-2-yl)be nzenesulfonamide, 2-methoxy-4-(trifluoromethyl)-N-(5,8-dimethoxy[1,2,4]triazolo[1,5-c]pyrimi din-2-yl)pyridine-3-sulfonamide, and 2-methoxy-6-methoxycarbonyl-N-(5,8-dimethoxy[1,2,4]triazolo[1,5-a]pyridin- 2-yl)benzenesulfonamide were prepared from appropriately substituted 2-amino[1,2,4]triazolo[1,5-c]pyrimidine and 2-amino[1,2,4]triazolo[1,5-a]pyridine compounds and appropriately substituted benzenesulfonyl chloride and pyridine-3-sulfonyl chloride compounds. The compounds were found to be useful as herbicides.

N-arylsulfilimine compounds, such as S,S-dimethyl-N-(2,6-dichlorophenyl)sulfilimine, were prepared and found to catalyze the reaction of aromatic sulfonyl chloride compounds, such as 2-chlorosulfonyl-7-fluoro-5-ethoxy[1,2,4]triazolo[1,5-c]pyrimidine, with aromatic amine compounds, such as 2,6-dichloroaniline, to form N-arylarylsulfonamide compounds, such as N-(2,6-dichlorophenyl)-7-fluoro-5-ethoxy[1,2,4]triazolo[1,5-c]pyrimidine-2 -sulfonamide. The aryl moiety of the N-arylsulfilimine catalyst and the aryl moiety of the aromatic amine compound were generally chosen to be identical.

N-(5,7-dimethoxy[1,2,4]triazolo[1,5-a]pyrimidin-2-yl) arylsulfonamide compounds were prepared from 2-amino-5,7-dimethoxy[1,2,4]triazolopyrimidine and appropriately substituted benzenesulfonyl chloride and pyridinesulfonyl chloride compounds. The compounds were found to be useful as herbicides.

N-arylsulfilimine compounds, such as S,S-dimethyl-N-(2,6-dichlorophenyl)sulfilimine, were prepared and found to catalyze the reaction of aromatic sulfonyl chloride compounds, such as 2-chlorosulfonyl-7-fluoro-5-ethoxy[1,2,4]triazolo[1,5-c]pyrimidine, with aromatic amine compounds, such as 2,6-dichloroaniline, to form N-arylarylsulfonamide compounds, such as N-(2,6-dichlorophenyl)-7-fluoro-5-ethoxy[1,2,4]triazolo[1,5-c]-pyrimidine- 2-sulfonamide. The aryl moiety of the N-arylsulfilimine catalyst and the aryl moiety of the aromatic amine compound were generally chosen to be identical.

Substituted N-(1-ethyl-4-pyrazolyl)triazoloazinesulfonamide compounds, such as N-(1-ethyl-5-methyl-3-(trifluoromethyl)-4-pyrazoyl)-5-methoxy-7-methyl-[1, 2,4]triazolo[1,5-c]pyrimidine-2-sulfonamide and N-(1-ethyl-5-methyl-3-(trifluoromethyl)-4-pyrazolyl)-5-methoxy-7-methyl[1, 2,4]triazolo[1,5-a]pyridine-2-sulfonamide, were prepared and found to possess selective herbicidal utility. The compounds are especially useful for the preemergence control of grassy weeds in soybeans