Herbicides

A compound of Formula (I)

• or a salt or N-oxide thereof, wherein,
• X1 is N or CR1;
• R1 is selected from the group consisting of hydrogen, halogen, cyano, C1-C6alkyl, C3-C6cycloalkyl, C2-C6alkenyl, C2-C6alkynyl, C1-C6alkoxy, —C(O)OC1-C6alkyl, —S(O)pC1-C6alkyl, NR6R7, C1-C6haloalkoxy and C1-C6haloalkyl;
• R2 is selected from the group consisting of halogen, cyano, nitro, C1-C6alkyl, C1-C6haloalkyl, C2-C6alkenyl, C2-C6alkynyl, C3-C6cycloalkyl, —C(O)OC1-C6alkyl, —S(O)p(C1-C6alkyl), C1-C6alkoxy and C1-C6haloalkoxy;
• R3 is —C(O)R9;
• R6 and R7 are independently selected from the group consisting of hydrogen and C1-C6alkyl;
• R4 and R9 together with the atoms to which they are joined form a 5-7 membered ring system containing from 1 to 3 heteroatoms, wherein at least one heteroatom is N, and any additional heteroatom is independently selected from S, O and N and wherein when said ring system comprises a ring carbon directly bonded to the nitrogen to which R4 is attached, said ring carbon is optionally substituted by an oxo moiety;
• n is independently 0 or 1;
• and
• p is 0, 1, or 2.