PROCESS FOR PRODUCING DIPHENYL-ETHER DERIVATIVES AND HERBICIDES COMPRISING THESE COMPOUNDS AS ACTIVE INGREDIENT

摘要

Phenoxy phthalide derivatives having the general formula II: CHEM wherein R1 represents a hydrogen or halogen atom or an alkyl or haloalkyl group; R2 and R3, which may be the same or different, each independently represents a hydrogen or halogen atom or an alkyl, haloalkyl, nitro or cyano group; each group R4 represents an an identical alkenyl or alkynyl group; and X represents an oxygen or sulphur atom; together with their preparation, and use as herbicides.