Patent GB-832990-A (GB)
Title: New basic ester of phosphorothiolic acid and pesticidal compositions containing it
Inventor: CALDERBANK ALAN
IPC: C07F9/165
Filed: 1956-10-19
Abstract: The invention comprises O,O1-diethyl S-(b -dimethylamino - b  - methyl) propyl phosphorothiolate of the formula <FORM:0832990/IV (b)/1> and acid addition salts thereof.  Specified acid addition salts are the hydrogen oxalate, toluene-p-sulphonate, hydrochloride, phosphate and picrate.  The ester may be obtained by heating a compound of the formula S : P(OET)(OET)Y wherein Y is a halogen atom either with a compound of the formula <FORM:0832990/IV (b)/2> wherein, of R3 and R4, one is hydrogen and the other a methyl radical, in the presence of an acid binding agent, or with a metal derivative of the said compound of the formula <FORM:0832990/IV (b)/3> wherin M is a metal atom and R3 and R4 are as defined above. Suitable acid binding agents are alkali metal carbonates, e.g. sodium carbonate and a suitable metal derivative is an alkali metal, e.g. sodium, derivative.  The reaction may be carried out in an inert diluent e.g. benzene.  The ester may also be obtained by heating a compound of the formula <FORM:0832990/IV (b)/4> wherein Y, R3 and R4 are as defined above either with a compound of the formula O= P(OET)(OET)SH in the presence of an acid binding agent or with a metal derivative of such compound of the formula O : P(OET)(OET) SM wherein M is a metal atom, especially sodium.  The reaction may be carried out in the presence of an inert diluent, e.g. ethanol.  In examples the ester is obtained by (1) heating a mixture of 1-dimethylamino-2-methylpropanol-2, sodium and benzene under reflux until the sodium no longer effervesces, removing residual traces of sodium by filtration, and then adding O,O1 - diethyl - phosphorochloridothionate to the filtrate and heating the mixture under reflux for 4 hours; (2) heating a mixture of 2-dimethylamino - 2 - methyl - propanol - 1, sodium and toluene under reflux until the sodium is dissolved, cooling to 20-25 DEG  C. and then adding dropwise O,O1-diethylphosphorochloridothionate and refluxing the mixture for 2 hours; and (3) by keeping a mixture of basic chloride (prepared by reacting thionyl chloride and 2 - dimethylamino - 2 - methyl propanol-1), sodium O,O1 - diethylphosphorothiolate and ethanol at 18-23 DEG  C. for 18 hours and then heating the mixture under reflux for 6 hours.  In each case the product after separation from the reaction mixture is treated with picric acid in ethanol to form the picrate.  The other specified acid addition salts may be obtained in a similar manner by mixing equimolar amounts of the basic ester and the appropriate acid in a mutual organic solvent with subsequent evaporation of the solvent where necessary.  The products have pesticidal properties (see Group VI).  Specifications 738,839 and 772,731 are referred to.ALSO:A pesticidal composition comprises O,O1-diethyl S - (b  - dimethylamino - b  - methyl) - propyl phosphorothioate of the formula <FORM:0832990/VI/1> and/or acid addition salt thereof (see Group IV (b)) as the active pesticidal ingredient or ingredients.  Specified acid addition salts are the hydrogen oxalate, the toluene-p-sulphonate, the hydrochloride, phosphate and picrate.  The pesticidal composition may contain a carrier and, if desired, an auxiliary agent and/or a plant nutrient. Specified carriers are talc, kieselguhr, bentonite, powdered chalk, water, and non-phytocidal organic solvents.  Specified auxiliary agents are dust binding agents, e.g. spindle oil, glycerol and wool fat, wetting, spreading and dispersing agents, e.g. sodium dinaphthylmethane disulphonate and sodium lauryl sulphate and sticking agents, e.g. glue and resin. Specified plant nutrients are urea and magnesium sulphate. Specifications 738,839 and 772,731 are referred to.