Isoxazole- and isothiazole-5-carboxamide derivatives, their preparation and their use as herbicides

摘要

There are provided isoxazole- and isothiazole-5-carboxamide compounds of formula I wherein X represents an oxygen or sulfur atom; W represents an optionally substituted alkyl, alkenyl, cycloalkyl, diakylamino, aryl, heteroaryl or aralkyl group; Y represents a hydrogen atom, a halogen atom, or an optionally substituted alkyl group; R1 represents a hydrogen atom, an optionally substituted alkyl group, or an optionally substituted acyl group; Z represents an optionally substituted C1-C4alkylene group with the proviso that when R1 is hydrogen and Z is methylene, then the optional substituent does not represent cyano, thiocarbamoyl or thiocarbamoyl-acyl; and R2 represents an optionally substituted aryl or heteroaryl group with the proviso that when X represents a sulfur atom then R2 does not represent a furyl group or a phenyl group optionally substituted with halogen and with the further proviso that when Z represents an unsubstituted methylene group, then R2 does not represent an unsubstituted phenyl group; or the N-oxides thereof; or the optical isomers thereof. There are further provided methods for the control of undesirable monocotyledenous and dicotyledenous plants species in the presence of a crop, such as a cereal crop or leguminous crop. Herbicidal compositions and methods of using same are also provided.