GB807610A - Bis-phosphoroamidothioates - Google Patents

Abstract

The invention comprises a phosphoroamidothioate having the formula <FORM:0807610/IV (b)/1> in which R is an alkyl radical containing 1 to 4 carbon atoms, X is haloaryl and n is 2 or 3. They may be obtained by reacting an O-haloaryl O-alkyl phosphorochloridothioate having the formula <FORM:0807610/IV (b)/2> with ethylene diamine or propylene diamine to replace one of the amino hydrogen atoms in each amino group of the diamine with phosphoryl groups. The reaction takes place smoothly in the temperature range of from - 10 DEG to 50 DEG C. and is carried out in an inert organic solvent such as benzene, toluene, methylene chloride or acetone and in the presence of a neutralizing agent for the by-product hydrogen chloride, e.g. an alkali metal hydroxide or an appropriate alkali metal salt, e.g. sodium carbonate, or by using an excess of the diamine. Examples are given for the production of phosphoroamidothioates in which R is methyl, CnH2n is ethylene, and X is 2,4,5-trichlorophenyl, 4-chlorophenyl, 2,4 - dichlorophenyl, and 2 - bromo - 4 - tertiarybutylphenyl respectively and in which R is ethyl, X is 2,4,5-trichlorophenyl and CnH2n is propylene (-CH2-CH(CH3)-). Other products which may be obtained are O,O1-bis-(4-bromophenyl) O,O1 - ditertiary-butyl N,N1 - ethylenebisphosphoroamidothioate, O,O1 - bis-(3,4 - dichlorophenyl) O,O1 - diethyl N,N1 - propylene bisphosphoroamidothioate, O,O1 - bis - (2 - bromo - 4 - chlorophenyl) O,O1 - dimethyl N,N1-ethylenebisphosphoroamidothioate, O,O1-bis - (4 - tertiary - butyl - 2 - chlorophenyl) O,O1 - dimethyl N,N1 - trimethylenebisphosphoroamidothioate, O,O1 - bis - (4 - methyl - 2 - chlorophenyl) O,O1 - diisopropyl N,N1 - ethylenebisphoroamidothioate, O,O1 - bis - (2,4,5 - tribromophenyl) O,O1 - diethyl N,N1 - propylenebisphosphoroamidothioate, and O,O1 - bis - (2,3,4,5 - tetrachlorophenyl) O,O1 - ditertiary-butyl N,N1 - trimethylenebisphosphoroamidothioate. The products are stated to be useful as pesticides (see Group VI). The O-haloaryl O-alkyl phosphorochloridothioates used as starting materials may be obtained by reacting from 2 to 3 molecular proportions of the corresponding alkanol with one molecular proportion of an O-haloaryl phosphorodichloridothioate at a temperature at which hydrogen chloride is formed as a product of reaction while continuously withdrawing hydrogen chloride in the gaseous state from the reaction mixture as formed, said temperature being at least 15 DEG C. below the boiling-point at 760 millimetres pressure of the alkanol used.ALSO:A pesticidal composition comprises a bisphosphoroamidothioate having the formula <FORM:0807610/VI/1> in which R is an alkyl radical containing 1 to 4 carbon atoms, X is haloaryl and n is 2 or 3 (see Group IV (b)) dispersed on a finely-divided solid carrier, or dispersed in oil or water or in a water emulsion. A suitable composition for use in controlling root-knot nematodes comprises an aqueous solution containing 10 parts by weight of O,O1-bis - (2,4,5 - trichlorophenyl) - O,O1 - dimethyl N,N1 - ethylenebisphosphoroamidothioate per million parts of ultimate mixture. Several other bis-phosphoroamidothioates are specified including O,O1 - bis - (2 - bromo (or chloro) - 4 - tertiary - butylphenyl) - O,O1 - dimethyl - N,N1 - ethylene - bisphosphoramidothioate and O,O1-bis - (2 - bromo - 4 - chlorophenyl) - O,O1 - dimethyl - N,N1 - ethylene - bisphosphoroamidothioate.