Processes for preparing herbicidal N-(substituted heterocyclicaminocarbonyl)-aromatic sulfonamides.

摘要

The invention provides a process for the preparation of a N-(haloheterocyclic-aminocarbonyl) aromatic sulfonamide of formula (wherein A is an optionally substituted homocyclic or heterocyclic aromatic group; X is H; Cl; Br; C1-C2 alkyl; CF3; CH3O; methoxymethyl or -CH2CH2OCH3; Y is Cl or Br; and Z is CH, N, C-Cl or C-CH3) characterised in that an aromatic sulfonamide A-SO2NH2 (wherein A is as defined above) is contacted with an isocyanate of formula (wherein X, Y and Z are as defined above). The resulting compounds may be further contacted with selected nucleophiles to yield further N-(substituted heterocyclicaminocarbonyl) aromatic sulfonamides.