Substituted pyridylsalicylaldehyde or -salicylic acid derivatives, their preparation and their use as herbicides

摘要

Substituted pyridylsalicylaldehyde and -salicylic acid derivatives of the formula I <IMAGE> I where R is a formyl group, a CO2H group or a radical which can be hydrolyzed to CO2H and the other substituents have the following meanings: R2 is halogen, alkyl, haloalkyl, alkoxy, haloalkoxy or alkylthio; X is nitrogen or CR13, R13 being hydrogen or halogen or together with R3 forming a 3- to 4-membered alkylene or alkenylene chain in which at least one methylene group is replaced by oxygen; R3 is halogen, alkyl, haloalkyl, alkoxy, haloalkoxy or alkylthio, or R3 is linked with R13 as indicated above to give a 5- or 6-membered ring; Y is oxygen or sulfur; Py is a substituted pyridine ring, are described.