N-Phenyl-sulphonyl-N'-diazinyl- and triazinyl-urea derivs - selective herbicides e.g. to restrict growth of cover crops and to prevent germination of potatoes

摘要

N-phenylsulphonyl-N'-diazinyl- and triazinyl-urea derivs. and their salts are new. A is 1-6C alkyl or 2-6C alkenyl, both opt. substd. by 1-4C alkoxy, 1-4C alkylthio, 1-4C alkylsulphinyl, 1-4C alkylsulphonyl 1-4C haloalkoxy, 1-4C haloalkylthio, 1-4C haloalkylsulphinyl or 1-4C haloalkylsulphonyl or A is 2-6C haloalkenyl. E is methine or N; X is O, S, sulphinyl or sulphonyl; Z is O or S- m is 1 or 2; R1 is H, halogen, 1-5C alkyl, 2-5C alkenyl, 1-4C haloalkyl, YR5, COOR6, NO2 or CONR7R8; R3 and R4 are each H, 1-4C alkyl, 1-4C alkoxy, 1-4C alkylthio, 1-4C haloalkyl, halogen or up to 4C alkoxyalkyl; R5 and R6 are each 1-5C alkyl, 2-5C alkenyl or 2-6C alkinyl; R7 and R8 are each H, 1-5C alkyl, 2-5C alkenyl or 2-6C alkinyl; Y is O, S, sulphinyl or sulphonyl. The intermediate phenylsulphonamide derivs. of formula (II) are also new. (a) R1, R2, A, M and X are as in (I) or (b) R1 and R2 are as in (I), but M=1, A=H and X is O or S. (I) are stable herbicides and plant growth regulators, which are easy to handle. (I) are highly selective and can be used e.g. in tropical areas to inhibit the growth of cover crops so they do not compete with the crops but without totally killing cover crops so that they still provide protection against soil erosion. (I) are esp. useful as selective herbicides in cereal, cotton, soya, maize and rice crops.