Herbicidal sulfonylureas, the preparation and use thereof

Abstract From the Canadian patent

Substituted sulfonylureas of the general formula I, , where R1 is hydrogen, C1-C3-alkyl C3-C6-alkenyl or C3-C6-alkynyl;, R2 is C1-C4-alkyl; R3 is hydrogen or halogen and A is halogen or a, radical, where B is oxygen or an alkylimino group R4 is hydrogen, C1-C6-alkyl which can carry up to three of the following: halogen, C1-C4-alkoxy, C1-C4-alkylthio C1-C4-halo-alkoxy, C1-C4-alkoxy-C1-C2-alkoxy C3-C7-cycloalkyl and/or, phenyl; C5-C7-cycloalkyl which can carry up to three C1-C4-alkyls; C3-C6-alkenyl or C3-C6-alkynyl and R5 is hydrogen, C1-C6-alkyl, or together with R4 is a C4-C6-alkylene chain in which one methylene can be replaced by oxygen or C1-C4-alkylimino, processes for their …