Patent GB-808853-A (GB)
Title: Process for preparing amidic esters of di-thiophosphoric acids, and insecticidal compositions including said derivatives
IPC: A01N57/10
Filed: 1956-03-15
Abstract: An amidic ester of dithiophosphoric acid having the general formula: <FORM:0808853/IV (b)/1> wherein R1 is an alkyl group (e.g. methyl, ethyl, n-propyl, isopropyl, n-butyl, or isobutyl) or an aryl group, R2 is a substituted or unsubstituted alkyl or aryl group (e.g. a methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, phenyl, chlorophenyl, or nitrophenyl group), R3 and R4 are the same or different and represent hydrogen or an alkyl group (such as a methyl, ethyl, n-propyl or isopropyl group) is obtained by treating a dithiophosphate of the general formula: <FORM:0808853/IV (b)/2> wherein Y is an alkali metal, an alkaline earth metal, or the ammonium radical and R1 is as defined above with an amide of an halogen substituted alkyl- or aryl-acetic acid of the general formula: <FORM:0808853/IV (b)/3> wherein X is halogen (Cl, Br or I) and R2, R3 and R4 are as defined above, preferably in the presence of a solvent for one or both of the reactants.  Alternatively, the free dithiophosphoric acid ester, i.e. a compound of the above general formula in which Y is H, may be used in conjunction with a basic compound of a metal which is sufficiently basic to neutralize the acid, e.g. Na2CO3, NaHCO3, K2CO3 KHCO3, or NaOH.  In this case the dithiophosphate salt is formed in situ.  Specified solvents which may be used are water, alcohols, ethers, ketones, esters, dioxane, and aromatic hydrocarbons.  Examples are given for the production of compounds of the formula: (1) (C2H5O)2PSSCH(CH3)CONHisoC3H7; (2) <FORM:0808853/IV (b)/4> ; (3) <FORM:0808853/IV (b)/5> ; (4) <FORM:0808853/IV (b)/6> ; (5) (CH3O)2 PSSCH(CH3)CONHisoC3H7; (6) (CH3O)2 PSSCH(CH3)CONHC2H5; (7) (C2H5O)2PSSCH (CH3)CONHC2H5; (8) (C2H5O)2PSSCH(CH3) CONH2; (9) (C2H5O)2PSSCH(C2H5)CONHC2 H5; (10) (isoC3H-O)2PSSCH(C2H5)CONHC2H5 (11) (CH3O)2PSSCH(C6H5)CONHC2H5; and (12) <FORM:0808853/IV (b)/7> The invention includes each of these compounds as new products. The products have pesticidal properties and may be used in pesticidal compositions (see Group VI).ALSO:A pesticidal composition comprises an inert diluent and an amidic dithiophosphate ester or mixture of such amidic dithiophosphate esters having the formula <FORM:0808853/VI/1> wherein R1 is an alkyl group or an aryl group, R2 is a substituted or unsubstituted alkyl or aryl group, and R3 and R4 are the same or different and represent hydrogen or an alkyl group such as methyl, ethyl, n-propyl or isopropyl (see Group IV (b)).  The composition may also include one or more known pesticidal agents such as insecticides and/or fungicides and may also include one or more plant feeding substances and/or fertilizers.  Specified compositions are acetone and benzene solutions of a compound of the formula (C2H5O)2PSSCH(CH3)CONHisoC3H7, and aqueous dispersions of the same compound.  Reference is also made to solutions of the same compound and of a compound of the formula (CH3O)2PSSCH(C6H5)CONHisoC3H7 in dimethylacetamide.  When R1 and R2 are alkyl radicals they may be methyl, ethyl, n-propyl, isopropyl, n-butyl, or isobutyl and R2 may also be phenyl, chlorophenyl, or nitrophenyl.