Process for preparing sulfonylureas

The prepn. of a sulphonyl-urea of formula (I) comprises reacting a sulphonyl chloride of formula (II) with a cyanate salt of formula MOCN (III) in the presence of an inert aprotic solvent and a heterocyclic amine base of formula Q (IV) at 0-60 deg.C and a pressure of 1-5 atmospheres for a time sufficient to give an isocyanate complex of formula (V) which is then reacted with an amino-heterocycle of formula (VI) in the presence of an aprotic solvent at 0-50 deg.C and a pressure of 1-5 atmospheres for a time sufficient to yield the sulphonyl-urea of formula (I). R1 = 1-4C alkyl; R2 = 1-2C alkyl or 1-2C haloalkyl; X = CH3 or N(CH3)2; Y = CH3, OCH3 or OCH2CF3; and Z = CH or N; M = Na or K; Q = Q1 or Q2; R3 = H, 1-2 alkyl, Br or Cl; R4 = H, 1-2C alkyl, Br or Cl; R3 and R4 taken together may form an aromatic ring where the structure becomes quinoline or isoquinoline; R5, R6 and R7 = 1-3C alkenyl, phenyl or benzyl; R5 and R6 can be taken together as -CH2CH2-A-CH2CH2- or -CH2CH2CH2CH2-; R5, R6 and R7 can be taken together as a gp. (i); A = O or NR8; and R8 = 1.3C alkyl.