Patent GB-1020807-A (GB)
Title: Thionothiol-phosphoric and -phosphonic acid esters and process for the production thereof
IPC: C07F9/60
Filed: 1964-08-07
Abstract: The invention comprises thionothiol phosphoric and phosphonic acid esters of the formula <FORM:1020807/C2/1> wherein R is an alkyl radical containing up to four carbon atoms, R1 is an alkyl or alkoxy radical containing up to four carbon atoms, R2 and R3 are hydrogen atoms or together stand for a fused benzene ring, R1 is a hydrogen atom or is a methyl radical if R2 and R3 stand for a fused benzene ring.  They may be produced by reacting an ester of the formula <FORM:1020807/C2/2> in which R, R1 and X have the same meanings as above and Hal is a halogen atom with a 2-mercapto-pyridine or quinoline of the formula <FORM:1020807/C2/3> in which R1, R2 and R3 have the same meanings as above or with the use of the mercapto compound in the form of a salt, preferably an alkali metal salt.  The reaction is preferably carried out in the presence of an inert organic solvent or diluent and, where the free mercapto compound is used in the presence of an acid-binding agent.  Preferred solvents are aliphatic alcohols and ketones, such as methanol, ethanol, acetone, methyl ethyl ketone, methyl isopropyl and methyl isobutyl ketone and dimethyl formamide while alkali metal alcoholates and carbonates e.g. sodium methylate sodium ethylate and potassium carbonate are satisfactory acid-binding agents.  Suitable reaction temperatures are between 20 DEG  C. and 80 DEG  C.  Catalytic amounts of alkali metal iodide may also be used. The thionothiol phosphoric and phosphonic acid esters may be used as the active ingredient in pesticidal compositions (see Division A5).ALSO:Thionsthiol phosphoric and phosphonic acid esters of the formula:  <FORM:1020807/A5-A6/1> wherein R is an alkyl radical containing up to four carbon atoms, R1 is an alkyl or alkoxy radical containing up to four carbon atoms.  R2 and R3 are hydrogen atoms or together stand for a fused benzene ring, and R1 is a hydrogen atom or is a methyl radical when R2 and R3 stand for a fused benzene ring atom (see Division C2) are used either alone or in combination with a solid or liquid diluent or carrier as pesticides.  They may also be used in combination with each other or with known insecticides and/or fertilisers. Examples of solid carriers are talc, chalk, bentonite and clay and as liquid carriers water, if necessary with commercial emulsifiers, alcohols, especially methanol or ethanol, ketones, especially acetone and methyl ethyl ketone, and liquid hydrocarbons may be used.  An example describes the use of varying concentrations of O,O-diethyl-thionothiol-phosphoric acid-s-[pyridyl-(2)-mercepto-methyl] ester and ethylthionothiol-phosphonic acid-o-ethyl-s-[pyridyl-(2)-mercapto-methyl]ester against aphids and spider miles on heavily invested beanplants, caterpillars on white cabbage, flies on drip wet filter papers and oat aphids on oat plants.  The aqueous dilutions of the active compounds are prepared by mixing them with dimethyl formamide as solvent, a benzyl hydroxy diphenyl polyglycol ether as emulsifier and finally diluting the premixture with water.  Application of the compositions may be by spraying or by watering the soild without wetting the leaves of the plants.