Herbicidal cyclohexane-1,3-dione derivatives

摘要

Compounds of the formula <IMAGE> I wherein: R5 is a bicyclic aryl or nitrogen-containing heteroaryl ring system such as naphthyl, quinolyl, isoquinolyl or tetrahydroisoquinolyl, optionally substituted by a wide variety of groups; R4 and R1 are preferably hydrogen but may be other groups and R2 and R3 are selected from alkyl, haloalkyl, alkenyl, haloalkenyl and alkynyl, show high general grass-killing activity with good selectivity to many broad-leaf crops and in some instances selectivity to small-grain cereals. Processes for the preparation of compounds of formula I, intermediates in the preparation of compounds I and the herbicidal properties of compounds I are described.