Patent GB-861860-A (GB)
Title: Organic dithiophosphoric compounds, their preparation and pesticidal compositions comprising same
IPC: C07F9/165
Filed: 1957-04-24
Abstract: The invention comprises compounds having the general formula <FORM:0861860/IV (b)/1> wherein R is alkyl, aryl, or aralkyl, R1 and R2 represent an -OH, -NH2, -O-alkyl, -O-aryl, or O-aralkyl group, or -OM where M is a monovalent metal, or R1 and R2 taken together represent <FORM:0861860/IV (b)/2> where M1 is a divalent metal, or <FORM:0861860/IV (b)/3> where R3 is a hydrogen atom or an alkyl group, and compounds of the above general formula wherein either one of R1 and R2 is an -OH group and the other one is an -NH2 or -O-alkyl group, each of said alkyl, aryl, and aralkyl groups containing up to ten carbon atoms.  The compounds, other than those in which R1 and R2 are -OH or -OM or R1 and R2 taken together are >OM1, may be obtained by reacting a dithiophosphoric acid diester of the formula (RO)2P(S)SH with an itaconic acid derivative of the formula CH2=C(COR1)(CH2COR2) Suitable reaction temperatures are from 20 DEG to 150 DEG  C. and, if desired, a solvent may be used, e.g. a low-molecular weight aliphatic alcohol, a low-molecular weight ketone, an aliphatic ester, an ether, an aromatic hydrocarbon, a nitro-aromatic hydrocarbon, a halogenated hydrocarbon, or dimethyl formamide.  A condensation catalyst, e.g. a nitrogenous base and a polymerization inhibitor, e.g. hydroquinone, may also be present. Compounds of the above formula in which R1 and R2 are -OH may be obtained by hydrolysing with a dilute acid the corresponding anhydride or diester prepared as above and compounds in which R1 and R2 are -OM or taken together are <FORM:0861860/IV (b)/4> may be obtained by reacting the corresponding anhydride obtained as above with the appropriate metallic base, e.g. sodium bicarbonate.  Also, water-insoluble salts of divalent metals may be obtained by reacting a solution of a salt of a monovalent metal prepared as above with a solution of an appropriate salt of the divalent metal.  Specified salts are the disodium salt and the calcium salt of S-(2,3-dicarboxypropyl)-O,O-diethyl dithiophosphate.  The products have pesticidal properties (see Group VI).ALSO:A pesticidal composition comprises as an active ingredient dispersed in an extending agent a compound of the formula <FORM:0861860/VI/1> wherein R is an alkyl, aryl, or aralkyl group, R1 and R2 represent an -OH, -NH2, -O-alkyl, -O-aryl or O-aralkyl group or -OM, where M is a monovalent metal, or R1 and R2 taken together represent <FORM:0861860/VI/2> where M1 is a divalent metal, or <FORM:0861860/VI/3> where R3 is a hydrogen atom or an alkyl group or a compound of the above formula wherein either one of R1 or R2 is an -OH group and the other one is an -NH2 or -O-alkyl group, each of said alkyl, aryl, or aralkyl group containing up to ten carbon atoms. The extending agent may be solid, semi-solid or liquid and the compositions may be in a form suitable for use as aerosols. Specified extending agents include petroleum jelly, soap, castor oil, olive oil, acetone, cyclohexanone, carbon tetrachloride, ethylene dichloride, tetrachlorethane, hydrogenated naphthalenes, alkylated naphthalenes, solvent naphtha, kerosene, powdered cork, powdered wood and powdered walnut shells.  Surface-active agents may also be present and other pesticides may be present, e.g. DDT, the gamma isomer of benzene hexachloride, 2,2-bis - (p - methoxyphenyl) - 1,1,1 - trichloroethane, salts of mercury, copper, or arsenic, or finely divided sulphur.  Typical active ingredients of the above formula are S-(2,3-dicarbomethoxypropyl) - O,O - di - n - propyl - (n-butyl, -iso-butyl, or -diethyl)-dithiophosphates and S - (2,3 - dicarbo - n - butoxy - propyl)-O,O-di-n-propyl dithiophosphate.