Herbicidal alkane carboxylic acid derivatives

The invention concerns novel compounds of the formula I I wherein: A, B, D, E, J1, J2, U and V are chosen from hydrogen, halogen, nitro, cyano, thiocyano, amino, substituted amino, alkyl, substituted alkyl, alkenyl, cycloalkyl, alkoxy, substituted alkoxy, alkylthio, alkylsulfinyl, substituted alkylsulfinyl, alkylsulfonyl, substituted alkylsulfonyl, sulfamoyl, substituted sulfamoyl, sulfo, carboxy, alkoxycarbonyl, carbamoyl, substituted carbamoyl and optionally substituted phenyl, phenoxy and phenylthio; R1 is chosen from hydrogen, alkyl, substituted alkyl, alkenyl, alkanoyl and alkoxycarbonyl; R2 is chosen from hydrogen, alkyl, substituted alkyl and alkenyl; or R1 and R2 together form an alkylidene group; W is chosen from cyano, thiocarbamoyl, the group -CH2Z wherein Z is chosen from halogen, hydroxy, mercapto, alkoxy, haloalkoxy, alkylthio and optionally substituted amino, and the group which may be a carboxylic acid group or a derivative thereof such as an acid salt, acid ester, acid amide, acid sulfonamide or acid oxime ester; X is chosen from oxygen and sulfur; Y is chosen from oxygen sulfur and optionally substituted imino; phi is chosen from oxygen and RAn wherein R is alkyl or benzyl and An is an anion; k is 0 or 1; and n is 0, 1 or 2. The compounds are herbicides and in further embodiments the invention provides herbicidal compositions containing as active ingredient a compound of formula I and a process for severely damaging or killing unwanted plants by applying to the plants or to the growth medium of the plants an effective amount of a compound of formula I.