DE1058046B - Process for the preparation of O, O-dialkylthionophosphoric acid-O-dichlorovinyl esters - Google Patents

Description

It is known that by reacting trialkyl phosphites produce O.O-dialkyl-phosphoric acid-O-dichlorovinyl ester with chloral without external heat supply can (see German patent application N 3376 IVb / 12o).

It has now been found that 0,0-dialkylthionophosphoric acid-O-dichlorovinylestcr the formula

Alkyl - Ο— ¹ Q-0 - CH = CCl ₂
Alkyl— Ο— Γ = S

obtained when 0,0-dialkylpliosphongic acid-S-aikylestcr Reacts with chloral at elevated temperature.

The ones used for the method according to the invention easily oxidizable 0,0-dialkylphosphorous acid-S-alkyl ester can be prepared by known methods, e.g. B. by using Alkyhnercaptans with Dialkylphosphorigsäurechloriden implements. (Cf. Arbusow, Nikonorow: Doklady Akad. Nauk S. S. S. R., 62, 75 [1948] = Chcm. Abstracts, Vol. 43 [1949], Col. 1004c.) In a preferred embodiment of the new method, the formed 0,0-dialkylphosphorous acid S-alkyl ester not, rather, the reaction product thus obtained reacts with the chloral.

This reaction is expediently carried out in an inert organic solvent, such as. B. benzene, toluene or chlorobenzene made. Temperatures in the range of 60 to 80 ⁰ C have proven themselves in the implementation of the inventive method particularly.

The new dichlorovinylthionophosphoric acid esters stand out - with moderate toxicity to warm-blooded animals - by good contact insecticidec and above all a systemic effect that the corresponding oxygen-analogous compounds, which in the published documents of the German patent application N 3376 IVb / 12o is not applicable.

example 1

19 g of Ο, Ο-diethylphosphorous acid sjithylester (bp.,: 45 to 46 ° C) are dissolved in 20 ecm BenzoT. To this end, 15 g of chloral are added while introducing nitrogen and continuously stirring at 40 ^{° C.} The temperature rises by itself at 65 ° C. is maintained, the reaction product for 1 hour at 7O ⁰ C and then fractionated it. There are 18 g of OO-diethyl-O-thionophosphorsäurc dichlorvinylesters from Kp ^ receive 87-88 ⁰ C as a clear, water-insoluble oil.

Analysis (for molecular weight 265):

Calculated S 12.6%, P 12.1%, Cl 26.8%;

found S 11.8%, P 12.0%, Cl 27.5%.

In the rat per os, the new compound shows a DL ₉₅ of 25 to 30 mg / kg. The present connection counteracts

Method of manufacture

of Ο, Ο-dialkylthionophosphoric acid

O-dichlorovinyl esters

Applicant:

Paint factories Bayer Aktiengesellschaft, Leverkusen-Bayerwerk

Dr. Gerhard Sdirader, Wuppertal-Cronenberg, has been named as the inventor

Flying 0.0001% 75%,

Mosquito larvae ... 0.0001% 100%,

Aphids 0.01% 100%,

Spider mites 0.01% 100%.

Example 2

32 g of ethyl mercaptan and 42 g of pyridine are dissolved in 400 ecm of benzene while continuously passing in nitrogen. Thereto is added dropwise with stirring 80 g ~ Diäthylphosphorigsäurechlorid (Kp. _12: 39 to 4O ⁰ C) dissolved in 100 cc of benzene. The reaction temperature of 40 ° C is maintained 1 hour and then at 70 ⁰ C 75 g chloral to. It is then heated for ^x \ _t hour at 8O ⁰ C, cooled to room temperature, and are the reaction product in 500 cc of ice water, which were 20 cc of 20% hydrochloric acid added. After shaking, the benzene solution is separated off, dried with sodium sulfate and fractionated. 97 g of O-O-diethyl-thionophosphoric acid-O-dichlorovinyl ester with a boiling point of: 87 ° C. are obtained.

Analysis (for molecular weight 265):

Calculated S 12.6%, P 12.1 ^ X 126.8%;

S found 11.6%, P _IW%%% _GM8,1.

Example 3 4 "** $

46 g of n-butyl mercaptan are dissolved together with 42 g of pyridine in 100 ecm of benzene. While passing nitrogen, then added dropwise at 0 ⁰ C 80 g Diäthylphosphorigsäurechlorid (dissolved in 100 cc of benzene) was added. The reaction product is kept at 10 ^° C. for 1 hour and then 75 g of chloral are added at 40 ^{° C.} The reaction takes place with continued stirring (the internal temperature rises to 65 ^{° C.).} The reaction product is kept at 80 ^° C. for a further hour and then worked as in Example 2

90 »528/422

described on. There are 65 g of OO-diethyl-O-thionophosphorsäure dichlorvinylesters from Kp _x. Obtained 85 to 87 ⁰ C.

Analysis (for molecular weight 265):

Calculated S 12.6 ⁰ Z ₀ , Cl 26.8%;

found S 11.1%, Cl 27.6 ° / ₀ .

Example 4

42 g of isopropyl mercaptan are dissolved together with 42 g of pyridine in 400 ecm of benzene. While constantly passing nitrogen through, 80 g of diethylphosphorous acid chloride (dissolved in 60 ecm of benzene) are added to the reaction product at ^{0 ° C.} It is held at 0 ^° C. for a further 1 hour and then 75 g of chloral are added at 40 ^{° C.} The temperature rises to 75 ^° C. This temperature is maintained for a further V for ₂ hours and then worked up as described in Example 2. 70 g of 0, 0-diethyl-thionophosphoric acid-O-dichlorovinyl ester with a boiling point of: 86 to 87 ° C. are obtained.

Analysis (for molecular weight 265):

Calculates S 12.6 per cent. P12, l ° / _0, C126,8 ° / _0;

found S 11.5%, P 11.3%, Cl 27.9%.

Example 5

14 g of Ethyhnercaptan are dissolved together with 17 g of pyridine in 100 ecm of benzene. For this you give in the stick

hydrogen at - 5 ° C 26 g Dimethylphosphorigsäurechlorid (b.p. _6O: 35 ⁰ C.). Then 16 g of chloral are added dropwise at + 10 ^{° C.} The temperature rises to 52 ⁰ C. It is heated for ¹ hour at _J2 7O ⁰ C and then worked up in the usual manner. There are 16 g of 0,0-Dimetbylthioiiophosphorsäure-O-dichlorvinylesters from Kp _x. Earn 70 ° to 71 ° C.

Analysis (for molecular weight 237):

Calculated S 13.4%, Cl 29.8%, P 12.8%;

found S 15.1%, Cl27.1%, P 11.7%.

Claims (1)

Claim: Process for the preparation of O, 0-dialkylthionophosphoric acid-O-dichlorovinyl esters the formula Alkyl - O - ΎΛ - O - CH = CCl ₂
Alkyl —- Ο— A = ^ S characterized in that Ο, Ο- Dialkylphosphorigsäure- Sjalky lester utasetzt with chloral at elevated temperature. Considered publications:
German Patent No. 845 226;
German patent application N 3376 IVb (published May 15, 1952).