DE1147798B - Pest repellants - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY kl. 451 9/36

INTERNAT. KL. A ol Π

GERMAN

PATENT OFFICE

EXPLAINING EDITORIAL 1147 798

B 44538 IVa / 451

REGISTRATION DATE: MAY 6, 1957

NOTICE
THE REGISTRATION
AND ISSUE OF
EDITORIAL: APRIL 25, 1963

The invention relates to new pesticides which have a phosphoric acid ester as an active ingredient the general formula

P I

Ι —Alk —O Ο —CH = CCl ₂

contain.

In this formula, Ri denotes an alkyl radical, R denotes hydrogen, halogen, an alkyl, alkoxy, nitro, carboxylic acid ester or nitrile group, η denotes a number from 1 to 5 and Alk denotes a straight or branched alkylene radical having 1 to 6 carbon atoms.

The compounds claimed according to the invention are both insecticidal and acaricidal. In addition to having a good long-term effect, they excel in pesticides

Applicant: CH. Boehringer Sohn, Ingelheim / Rhein

Dr. Karlzeile and Dr. Richard Sehring,

Ingelheim / Rhein, have been named as inventors

also by a very low toxicity to warm-blooded animals compared to similarly built animals Phosphoric acid esters, from.

The following table lists the effectiveness and toxicity of some of the new compounds listed against a known similarly constructed connection.

2. (
( LD ₅₀ concentration Laboratory animals Mortification
in «/ ο 1. CH ₃ OO
P.
CH ₃ O OCH = CCl ₂ t 50 0.05
0.01
0.02 American
Scrape
To fly
Red spider 95
100
30th (known) P.
/ \
: ₂ H4O OCH = CCl ₂ 3 ~ / - Cl 80 0.05
0.01
0.02 American
Scrape
To fly
Red spider 100
100
100 (according to the present invention)

309 577/325

( LD. *, concentration Laboratory animals Mortification 1I ₂ H ₄ O OCH = CCl ₂ in % 3. CH ₃ OO S— <C> —ei
(according to the present invention) \ ^ > 600 0.05 American 100 P. Scrape / \ 0.01 To fly 100 0.02 Red spider 98

The values given in the table for the LD 50 were obtained by oral administration of the Active ingredients determined in white mice.

The long-term acaricidal action of the compounds used according to the invention is based on the following experiment emerge:

Bean plants with one of the two new compounds listed in the table 2 or 3 (0.05% active ingredient concentration) were sprayed with red spiders after 8 days populated. 85 to 90% of the animals died within a short time. The same attempt was made with O ^ -Dimethyl-l ^ -dicarbethoxyethyl dithiophosphate carried out. 10% of the red spiders placed on the plants died.

The following is the result of a comparative experiment reproduced, in which a compound claimed according to the invention with a similar built connection of the German patent 968 486 is compared.

In the comparison experiment, the LT50 (that is the time in which 50% of the test animals were killed are determined on house flying. The acetone solution was used under comparable conditions the active ingredients are applied to filter paper and then, after the acetone has evaporated, the flies on put the paper on.

The following results were obtained:

link

LT50 (minutes)
0.01% 0.05%

O - ^ - chloroethyl-Oj / J-dichlorovinyl-S-ip-chlorophenyl thiophosphate (according to German patent specification 968 486)

O OC ₂ H ₄ Cl χ X /

Xs- ρ

0-CH = CCl ₂

O-methyl-O-ip-chlorophenyl-mercaptoäthylVO-dS ^ -dichlorovinyl-phosphate (according to the present invention) 300

200

13th

0-CH = CCl ₂

The table shows that the compound claimed according to the invention of the compound according to the German patent specification 968 486 is far superior. The rapid onset of action is particularly impressive in the compounds claimed according to the invention.

The compounds of the formula I are prepared in a manner known per se by condensation of phosphites of the general formula
RiO

P —O —R '

-Alk —O

in which R 'denotes a lower alkyl radical and Ri, R, Alk and η have the meaning given above, with chloral.

The phosphites of the formula II used as starting compounds can not be claimed here Way by reacting trialkyl phosphite (in excess) with alcohols of the formula

Alk-OH

III

in which R has the meaning given above, are ^{prepared at 120 °} C. and while passing an inert gas through the reaction mixture at the same time. In this reaction, 1 mol of alkanol is split off. The excess trialkyl phosphite is distilled off and the residue is rectified.

The phosphoric acid esters claimed according to the invention are non-distillable oils. The following connections of the formula I are listed, for example:

O-methyl-O- (p-chlorophenylmercaptoethyl) -O - (/ S, /? - dichlorovinyl) phosphate

56 g (0.2 mol) of Ο, Ο-dimethyl-Op-chlorophenylmercaptoethylphosphite are dissolved in 200 ml of toluene. At 20 ^° C., 29.4 (0.2 mol) chloral are added dropwise. To complete the reaction, the mixture is ^{heated to 50 °} C. for 1 hour. After the solvent has been distilled off, a colorless, non-distillable oil is obtained.

Yield: 72 g = 95.5% of theory.

O-ethyl-O- (p-chlorophenylmercaptoethyl) -O - (/ 8, ^ - dichlorovinyl) phosphate

61.6 g (0.2 mol) of q, O-diethyl-O- (p-chlorophenylmercaptoethyl) phosphite are dissolved in 200 ml of toluene. At 20 ^° C., 29.4 g (0.2 mol) of chloral are added dropwise. To complete the reaction, the mixture is ^{heated to 50 °} C. for 1 hour. After the solvent has been distilled off, a colorless, non-distillable oil is obtained.

Yield: 75.0 g = 96% of theory.

O-methyl-O- (phenylmercaptoethyl) -O - (/ ?, j3-dichlorovinyl) phosphate

49.2 g (0.2 mol) of O, O-dimethyl-O- (phenylmercaptoethyl) phosphite are dissolved in 200 ml of benzene. At 20 ^° C., 29.5 g (0.2 mol) of chloral are added dropwise. To end the reaction, the mixture is then heated ^{to 50 ° C. for 1 hour.} After the benzene has been distilled off, a colorless, non-distillable oil remains.

Yield: 67 g = 97.5% of theory.

O-methyl-O- (p-tolylmercaptoethyl) -O - (/?, / S-dichlorovinyl) phosphate

52 g (0.2 mol) of O, O-dimethyl-O- (p-tolylmercaptoethyl) phosphite are dissolved in 200 ml of ether. At 20 ° C., 29.5 g (0.2 mol) of chloral are added dropwise. To terminate the reaction, the reaction mixture is refluxed for IV2 hours. To Distilling off the ether leaves a colorless, non-distillable oil.

Yield: 68 g = 95% of theory.

The following examples illustrate the invention.

example 1
Grit

2 parts of active ingredient are ground homogeneously with 98 parts of kaolin.

Example 2
suspension

10 parts of active ingredient, 10 parts of naphthalenesulfonic acid Sodium and 80 parts of kaolin are ground homogeneously and before use with 50 to 2001 Water diluted.

Example 3
emulsion

50 parts of active ingredient are in 35 parts of ricinoleic acid butyl ester sulfonate dissolved and mixed with 15 parts of xylene. This solution becomes the desired concentration in the appropriate amount of water emulsified and diluted with 250 to 1000 liters of water before use.

Example 4
Solution (spray)

5 parts of active ingredient are dissolved in 95 parts of petroleum ether.

Example 5
Aerosol

5 parts of active ingredient are in 95 parts of difluorodichloromethane solved.

Claims (2)

PATENT CLAIMS: 1. Pesticides, characterized by the content of a phosphoric acid ester of the general formula R ₁ O _x 0 P I ^ -Alk -O 0 -CH = CCl ₂ in which Ri is an alkyl radical, R is hydrogen, halogen, an alkyl, alkoxy, nitro, carboxylic acid ester or nitrile group, η is a number from 1 to 5 and Alk is a straight or branched alkylene radical having 1 to 6 carbon atoms, as active ingredient. 2. Pesticide according to claim 1, characterized in that it contains as active ingredient a compound which, by condensation of a phosphite of the general formula _Rl0 P - O - R ' —Alk - in which R 'denotes a lower alkyl radical and Ri, R, Alk and η have the meaning given in claim 1, has been obtained in a manner known per se with chloral. Considered publications:
German patent application F 10662 IV b / 12 ο (published on March 15, 1956).