| abstract |
According to the process of the invention, O, O-diethylthiophosphoryl chloride and dimethylformamide or Ν,-dimethylacetamide form an O, O-diethylthionophosphoramine complex of formula (I) wherein R is hydrogen or methyl; the complex, which may be prepared in situ in the reaction mixture, is reacted in an organic aprotic solvent, preferably acetone or xylene, in the presence of an alkali metal carbonate acid binding agent with 2-hydroxyquinoxaline to the final product. When xylene is used as the reaction medium, the O, O-diethyl-2-quinoxalinylphosphorothioate of formula (I) is obtained directly in an xylene solution suitable for pesticide formulation. O S II ^ OC1 Hj K 0 C 2 Hj Figure I Scope of the description: 6 pages (including Figure 3) ch5 _ J? s © I H / OCaHy N = C-0- F. III. Figure EN 203245 A -1- |