Use of 2-phenoxypyrimidines as herbicides

Abstract

A process of inhibiting the growth of, severely damaging, or killing plants which process comprises applying to the plant or to the growth medium thereof an effective amount of a composition comprising as active ingredient a compound of formula I: ##STR1## wherein A, B and D are independently chosen from the group consisting of hydrogen, halogen, hydroxy, nitro, cyano, thiocyano, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkoxy, optionally substituted alkenyloxy, optionally substituted alkynyloxy, optionally substituted alkylthio, optionally substituted cycloalkyl, optionally substituted amino, optionally substituted phenyl, carboxy, alkoxycarbonyl, optionally substituted carbamoyl, sulfo, alkylsulfonyl and optionally substituted sulfamoyl; R.sup.2, R.sup.3, R.sup.4, R.sup.5 and R.sup.6 are independently chosen from the group consisting of hydrogen, halogen, nitro, cyano, thiocyano, formyl, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted cycloalkyl, optionally substituted alkylcarbonyl, optionally substituted amino, optionally substituted phenyl, optionally substituted carbamoyl, sulfo, alkoxysulfonyl, optionally substituted sulfamoyl and the groups YR.sup.1 and ##STR2## wherein Y is oxygen or sulphur and R.sup.1 is chosen from the group consisting of hydrogen, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted cycloalkyl, optionally substituted acyl, optionally substituted alkoxycarbonyl, optionally substituted phenyl and the cation of an inorganic or organic base; X is oxygen or sulphur; and B, R.sup.3 and R.sup.5 are not all hydrogen; or a geometrical or optical isomer thereof; or a tautomer thereof; or a salt thereof; and a carrier therefor.