2-substituted 6-phenyl-benzoic acid derivatives, their preparation and their use as herbicides.

摘要

A herbicidally active biphenyl derivative and composition containint it is represented by the formula (I) <CHEM> wherein R<1> is a hydrogen atom or a group represented by the formula <CHEM> (wherein each of R<4> and R<5>, which may be the same or different, is a hydrogen atom, a C1-C6 alkyl group, a C3-C8 cycloalkyl group, or a phenyl group optionally substituted with at least one moiety selected from C1-C6 alkyl groups, halogen atoms and C1-C6 alkoxy groups, or a benzyl group optionally substituted with at least one moiety selected from C1-C6 alkyl groups, halogen atoms and C1-C6 alkoxy groups, or R<4> and R<5> are bonded together at their ends to form a C4-C6 alkylene group optionally substituted with at least one C1-C6 alkyl group; or R<4> and R<5> are bonded together at their ends to form a C4-C6 alkylene group containing one or more hetero atom(s) selected from oxygen, sulfur and nitrogen atoms, optionally substituted with at least one C1-C6 alkyl group), each of R<2> and R<3>, which may be the same or different, is a C1-C6 alkyl group, a C1-C6 alkoxy group, a C1-C6 alkylthio group, a halo C1-C6 alkoxy group or a halogen atom, each of X<1>, X<2> and X<3>, which may be the same or different, is a hydrogen atom, a hydroxyl group, a C1-C6 alkyl group, a halo C1-C6 alkyl group, a C1-C6 alkoxy group, a nitro group, a cyano group or a halogen atom and Y represents an oxygen atom or a sulfur atom; or agriculturally acceptable salt thereof.