HERBICIDALLY ACTIVE BICYCLIC 1,3-DIONE COMPOUNDS

Disclosed are 3-phenyl-bicyclo[3.2.1]octane-2,4-dione and 3-phenyl-bicyclo[3.2.2]nonane-2,4-dione derivatives as represented by the general formula (I), wherein; R1 is methyl, ethyl, n-propyl, isopropyl, cyclopropyl, halomethyl, haloethyl, halogen, vinyl, ethynyl, methoxy, ethoxy, halomethoxy or haloethoxy; at least one of R2 and R3 is optionally substituted phenyl or optionally substituted heteroaryl; R4 is hydrogen, methyl, ethyl, n-propyl, iso-propyl, halomethyl, haloethyl, halogen, vinyl, ethynyl, methoxy, ethoxy, halomethoxy or haloethoxy; X is optionally substituted alkylene; Y is optionally substituted alkylene or optionally substituted alkenylene; and wherein the remaining substituents are as defined herein. Further disclosed is a herbicidal composition which comprises a compound as defined above; formulation adjuvants; and which optionally further comprises an additional herbicide; for controlling grasses and weeds in crops of useful plants such as cereals, cotton, soybeans, sugar beet, sugar cane, plantation crops, rape, maize or rice.