O-ALKYL-S-SUBSTITUTED-O-NAPHTHYL-PHOSPHOROTHIOLATES

1322528 Preparing thiophosphate esters having pesticidal properties BAYER AG 20 Oct 1970 [21 Oct 1969] 49741/70 Heading C2P Compounds of the general formula wherein R1 is C 1 -C 4 alkyl, R2 is an alkyl or alkenyl radical of up to 4 carbon atoms, or a group R3OCH 2 CH 2 - in which R3 is C 1 -C 4 alkyl, X is halogen, e.g. Cl, Br, F or I, preferably Cl or Br, and n is 0, 1, 2 or 3, are obtained by either (a) reacting a compound of the formula (R1O)(R2S)P(O)Hal, where Hal is halogen, with a compound: where M is H, a metal or an ammonium, or (b) reacting a compound of the formula with a compound: HalR2; where M and Hal are as defined above. Either process can be carried out in the presence of an inert solvent or diluent. In reaction (a) an acid binder may be present when M is hydrogen. The products have insecticidal, fungicidal, nematocidal, and other biocidal properties and are also useful as herbicides and as plant growth controlling agents. They can be used as active ingredients in conventional pesticidal compositions containing solid, liquid or liquefied gaseous diluents or carriers and which may additionally contain other active compounds or fertilizers. Potassium O - ethyl - O - (1 - naphthyl) - thiophosphate is obtained in an example by reacting the corresponding O-alkyl-O-naphthyl thionophosphoryl chloride with KOH in the presence of water and dioxan first at 40-50‹ C. and then at 60-70‹ C. to complete the reaction.