DE1063155B - Process for the preparation of thiophosphoric acid esters - Google Patents

Description

It has been found that insecticidally active thiophosphoric acid esters can be obtained by that either optionally substituted diphenylmethylcarbinols with 0,0-dialkylthionophosphoric acid monochlorides in the presence of acid binders, expediently tertiary amines and preferably at elevated levels Temperatures are brought to reaction or that optionally substituted Diphenylmnethylchloride with Salts of Ο, Ο-dialkylthionothiol or dialkylthiol phosphoric acids be reacted in the presence of suitable solvents.

For the preparation of the thiono compounds, it is also possible to use Ο, Ο-dialkylphosphoric acid monochlorides to implement with diphenylmethylcarbinols in the presence of acid binders and by subsequent Reaction with sulfur to convert the phosphorous acid triesters into the corresponding thionophosphoric acid esters.

The reaction is preferably carried out at room temperature or at a slightly elevated temperature. so

The new thiophosphoric acid esters obtainable by both processes stand out in addition to good general contact insecticidal properties in particular Point out that they work very well against mosquitoes.

The compounds according to the invention are used in the manner customary for phosphoric acid esters and manner, d. H. preferably in combination with suitable inert extenders or diluents. So are for Dusts especially talc, bentonite, kieselguhr, chalk or similar are well suited. If necessary, can by adding an emulsifier, such dusts can also be converted into a form that can be emulsified in water. For the Use as liquid »sprays«, water is particularly suitable as a diluent, after through previous use Mixture with a solubilizing agent, e.g. B. dimethylformamide or acetone, and after adding one commercially available emulsifier, the compounds according to the invention have been brought into an emulsifiable form are. Other suitable liquid diluents are 4 <> but also low molecular weight alcohols and Hydrocarbons.

German Patent 949 231 already discloses compounds analogous to those of the invention Kind known. These connections contain 5 in place of * of two phenyl radicals only one phenyl radical. The known S-4-chlorobenzyl ester, 0,0-diethylthiolphosphoric acid, was compared (I) with the O.O-diethylthionothiolphosphoric acid S - ^^ - dichlorobenzhydryl ester obtainable according to the invention (II) with regard to the insecticidal 5 »effectiveness against flies, aphids and spider mites. The better properties of the compounds obtainable according to the invention are evident from the following Table shows:

Method of manufacture
of thiophosphoric acid esters

Applicant:

Paint factories Bayer Aktiengesellschaft,
Leverkusen-Bayerwerk

Dr. Hanshelmut Schlör, Wuppertal bans,
and Dr. Dr. hc Gerhard Schrader,

Wuppertal-Cronenberg,
have been named as inventors

I II

Flying 0.1% 100% 100%

0.01% 0% 100%

0.001% 0 / .60%

Aphids 0.1% 80% 100%

Spider mites 0.01% 100% 100%

0.001% 0% 50%

The following examples provide an overview of the claimed processes:

example 1

, _v S

/ 'V II OC ₁ Hb.

CHO-P '

"OC ₂ H ₆

46 g (0.25 mol) of diphenylmethylcarbinol (benzhydrol) (m.p. 67 ° C) and 20 g (0.25 mol) of pyridine are in Dissolved 100 ecm of chloroform. 48 g (0.25 mol) of Ο, Ο-diethylthionophosphoric acid monochloride are added at 30 ° C. with stirring added. The reaction product is kept at 60 ° C. for a further 1 to 2 hours and then cooled to room temperature and pour the reaction product into ice water to which 10 ecm of dilute hydrochloric acid were added. Man separates the chloroform-containing phase from the aqueous phase Solution two more times with 5 ecm of water, Dries over sodium sulphate and wdtfili | brt in vacuo the solvent off. The K% k £ & MfJ & becomes the removal volatile constituents no longer briefly under a pressure of 1 mm of mercury at a bath temperature kept at 60 ° C. One gets in this way

909 607/420

Claims (1)

77 g of the 0,0-diethylthionophosphoric acid benzhydryl ester as a pale yellow, water-insoluble oil. Yield 92 "/ ₀ of the theory. In the rat per os, the new ester shows an average value Toxicity of 25 mg / kg. A 0.01% suspension of the ester still kills mosquitoes completely. 0.1% solutions of the ester are effective kills caterpillars and spider mites. Cl- Cl-, Example 2 CH-O - OC ₅ H, OC ₂ H ₅ OCH, sulfate and removes the solvent in vacuo. In this way, 46 g of Ο, Ο-diethylthiolphosphoric acid S-benzhydryl ester are obtained as a pale yellow, water-insoluble oil. Yield 68 ° / ₀ of theory. The new ester showed a mean toxicity of 500 mg / kg in the rat per os. 0.01 ⁰ / o solutions kill spider mites 100 ⁰ / "strength from. 63 g (0.25 mol) of 4,4'-dichloromethylcarbinol (temperature = 93 to 95 ° C) and 26 g (0.2SMoI) of triethylamine are dissolved in 100 ecm of benzene. Anhydrous nitrogen is passed through the reaction product and 47 g (0.3 mol) of Ο, Ο-diethylphosphorous acid chloride - dissolved in 50 ecm of benzene - are then added at 30 ° C. with stirring. It is held at 30 ° C. for a further hour and then 9.5 g (0.3 mol) of finely powdered sulfur are added. The temperature of the reaction product rises by itself to 50 ° C. The mixture is kept ^{at 70 ° C. for 1} Z ₂ hours and then cooled to room temperature. After working up as described in Example 1, 72 g of the new ester are obtained in the form of a light green, water-soluble oil. Yield 71 ° / ₀ of theory. The OO-diethylthionophosphoric acid ^^ '- dichlorobenzhydryl ester shows a mean toxicity of 100 mg / kg per os in rats. 0.01 '/, strength solutions kill flies and spider mites 100 ° / ₀ strength from. Mosquitoes are also killed with certainty in the same concentration. Example 3 OC ₂ H ₅ Cl
Cl- ^ Example 4 CH- S— P ' a H _K OC ₂ H ₅ 41 g (0.15 mol) of 4,4'-dichlorodiphenylchloromethane with a temperature of 59 to 60 ° C and 35 g (0.17 mol) of 0.0-diethyldithiophosphate ammonium are heated to boiling in 80 ecm of methyl ethyl ketone for 1 hour. It is then cooled to room temperature, poured into plenty of water, the precipitated oil is dissolved in benzene and shaken several times with 50 ecm of water each time. After drying over sodium sulfate, the solvent is distilled off. This gives 50 g of 0,0-Diäthylthionothiolphosphorsäure-S-4,4'-dichlorbenzhydiylesters as white crystals, melting at - 47 to 49 ° C. "yield 79 ° / ₀ of theory. In the rat per os, the new ester shows an average value Toxicity of 1000 mg / kg. 40 g (0.2 mol) of diphenylchloromethane (temperature = 18 to 19 ° C) and 40 g of 0.0-diethyltniolphosphoic acid ammonium are dissolved or suspended in 120 ecm of water and stirred at 25 ° C for 24 hours. Then you separate the oil formed, takes it up in chloroform, washes it twice with 10 ecm of water each time, dries over sodium P.VTENTANS PEUCH: Process for the preparation of thiophosphoric acid esters, characterized in that optionally substituted diphenylmethylcarbinols in the presence of acid binders with 0,0-dialkylthionophosphoric acid monochlorides be reacted or that optionally substituted diphenylmethylcarbinols with 0,0-Dialkylphosphorigsäuremonochloriden in the presence of acid bindersii are reacted and then converted into the corresponding thiono compounds with sulfur or that optionally substituted diphenylmethyl halides with salts of O, 0-dialkylthiol or Ο, Ο-dialkylthionothiolphosphoric acids be made to react. Considered publications:
German Patent Nos. 836 349, 917 668, 5 "935 432, 949 231; German interpretation document No. 1 007 770.