DE1770194C - 1,2,5-Thiadiazolyl-phosphoric acid esters and their use as pesticides - Google Patents

Description

wherein X is oxygen or sulfur, R ¹ and R ^{2 are} QC ^ -alkyl and R is hydrogen, chlorine, methyl, r _{5 is} phenyl, cyano, metaoxycarbonyl or dimethylcarbamyl

2. Use of the compounds according to Claim 1 as pesticides.

IO

OH

N
\

(H)

or its alkali salt with a halide of the general formula

R ¹ OX

N,

cN

X OR ¹

II /
ρ

OR ²

wherein X is oxygen or sulfur, R ¹ and R ^{2 are} C ₁ -C ₄ -alkyl and R is hydrogen, chlorine, methyl, phenyl, cyano, methoxycarbonyl or dimethylcarbamyl.

The compounds are pesticidal, in particular insecticidal, and are therefore used as pesticides used. Compounds especially because of their strong insecticidal effectiveness preferred are:

! ^, S-thiadiazol- ^ yl-thionophosphoric acid-

dimethyl ester,
l ^^ thiadiazol- ^ yl-thionophosphoric acid-

diethyl ester,
l ^ S-Thiadiazol ^ yl-thionophosphoric acid-

methyl isopropyl ester and
l ^ S-Thiadiazol- ^ yl-phosphoric acid-diethyl-

ester.

The application takes place in the manner known for pesticides, i. H. in the form of wettable powders, dusts, granules, solutions, emulsifiable concentrates, emulsions and Pastes that are formulated with the usual solid and liquid carrier materials and excipients. In general, wettable powders contain 25, 50 or 75%, granulates 0.5 to 25%, and emulsifiable concentrates 10 to 50% (w / v) and pastes 10 to 60% active ingredients.

It has been shown that C ^ rrfindungsgemäßen compounds compared to known substances used in the same field of application comprise a convenient, low mammalian toxicity. The ii

P - shark

Uli)

The invention relates to 1,2,5-thiadiazolyl-phosphoric acid esters the general formula

R ² O '

manufactured.
The hydroxyl used as starting material

1,2,5-thiadiazoles can according to the optionally modified method of Ross and Smith (Journal of the American Chemical Society, 1964, p. 2861) and Weinstock et al (Tetrahedron Letters 1966, p. 1263).

the invention is explained in more detail in the following examples; the structure of the compound was each determined by elemental analysis as well as NMR and IR analysis.

example 1

Production of l ^^ - thiadiazol- ^ yl-thionophosphoric acid dimethyl ester

S OCH ₃

π ir— Ο —Ρ

OCH ₃

1.4 g of dry powdered potassium carbonate and 1.6 g of dimethylthionophosphoric acid ester chloride were

which is added to a solution of 1.0 g of 4-hydroxy-1,2,5-thiadiazole in 15 cm ^{3 of} dry methyl isobutyl ketone and the mixture is ^{stirred at 90 to 100 °} C. for 2 hours. After cooling, the reaction mixture was filtered and the solvent was removed from the filtrate under reduced pressure. What remained was an oil which was purified on a column with silica gel using petroleum ether (boiling point 40 to 60 ° C.). The title compound was obtained as a yellow oil. Yield: 32%.

C ₄ H ₇ PN ₂ S ₂ O ₃ :

Calculated ... C21.3, H3.1, P 1.3.7%;
found .... C 21.4, H 3.1, P 13.7%.

Example 2

Preparation of 3-phenyl-1,2-thiadiazQl-4-yl-t-monophosphoric acid dimethyl ester

S OCH ₃

I /

1.0 g of 3-phenyl-4-hydroxy-1,2 ^ -thiadiazole was reacted with the equivalent amount of KOH, dissolved in ethanol, to form the potassium salt of hydroxythiadiazole; the solvent vrarde evaporated, the residue taken up in benzene and the solvent evaporated again. The dried potassium salt was then dissolved in 20 cm ^{3 of} methyl isobutyl ketone, and 900 mg of dimethylthionophosphoric acid serchloride were added. The mixture was ^{stirred at 100 °} C. for 4 hours, filtered and the solvent was drawn off from the filtrate. The crude reaction product was purified by silica gel column chromatography using benzene / petroleum ether; the title compound was obtained as a colorless oil. Yield: 70%.

C ₁₀ H _n PN ₂ S ₂ O ₃ :

Calculated ... C 39.8, H 3.6. N 9.3%;
found .... C 40.6, H 3.8, N 9.1%.

Example 3

Production of 1,2,5-thiadiazol-4-ylphosphoric acid diethyl ester

O OC ₂ H ₅
O -P

OC ₂ H ₅

770194

rid of the title compound as a pale yellow oil. Yield: 25%.

C ₆ H ₁₁ PN ₂ SO ₄ :

Calculated ... C 30.2, H 4.6, P 13.0%; Serunds .... C 30.2, H 4.8, P 13.2%.

Example 4

Production of S-KN-Dimethylcarbamyl-

l ^^ - thiadiazol-4-yl-thionophosphoric acid dimethyl-

ester

0.04 mol of 4-hydroxy-3-cyano-1,2,5-thiadiazole were ^{refluxed for 4 hours with 50 cm 3 of} water and 0.08 mol of KOH. The reaction mixture was acidified, extracted with ether, the ether solution dried and evaporated. The solid residue obtained was ^{refluxed with 34 cm 3 of} thionyl chloride and the excess thionyl chloride was then distilled off under reduced pressure. The residue was dissolved in dry ether and 0.1 mol of anhydrous dimethylamine dissolved in dry ether was added, the temperature being kept between 5 and 10 ° C. The ether layer was evaporated and the residue was purified by chromatography and sublimed on a column with silica gel using chloroform-methanol as the eluent. 4-Hydroxy-SN.N-dimethylcarbamyl-IAS-thiadiazole was obtained.

This hydroxythiadiazole was then phosphorylieit according to Example 2; the title compound was identified as get oil. Yield: 50%.

C ₇ H ₁₂ PN ₃ S ₂ O ₄ :
Calculated ... C 28.3, H 4.1, N 14.1, P 10.4%;

40 found .... C 29.1, H 4.1, N 14.7, P 9.3%. Example 5

According to the procedures given in Examples 1 to 4, further phosphorylated 1,2, 5-thiadiazoles synthesized, which are summarized in the following table.

OR ¹

50

Following the procedure of Example 2, using phosphoric acid diethyl ester chloride instead of dimethylthionophosphoric acid ester

R. R ¹ R ² a) CH ₃ OCO- CH ₃ CH ₃ b) - CN CH ₃ CH ₃ c) Cl CH ₃ CH ₃ d) CH ₃ CH ₃ CH ₃ e) H C ₂ H ₅ C ₂ H ₅ 0 H CH ₃ CH (CH ₃ ), G) H CH ₃ (CH ₂ ) ₃ CH ₃ H) CH ₃ C ₂ H ₅ C ₂ H ₅

S.
S.
S.
S.
S.
S.
S.
O

Molecular formula

C ₆ H ₉ PN ₂ S ₂ O ₅

C ₅ H ₆ PN ₃ S ₂ O ₃

C ₄ H ₆ PN ₂ S ₂ O ₃ Cl

C ₅ H ₉ PN ₂ S ₂ O ₃

C ₆ H ₁₁ PN ₂ S ₂ O ₃ -

C ₆ H ₁₁ PN ₂ S ₂ O ₃

C ₇ H ₁₃ PN ₂ S ₂ O ₃

C ₇ H ₁₃ PN ₂ SO ₄

5 1,770,194 yield
· /. Mp 40-41 ° C connection Hementaianalysc 25th oil a) Calculated...
found C 25.4, H 3.2, P 10.9%;
C 25.7, H 2.9, P 10.8%. 43 Ul b) Calculated...
found C 23.9, H 2.4, N 16.7, P 12 ^ 2%;
C 23.8, H 2.7, N 16.2, P 12.1%. 36 oil c) Calculated...
found C 18.4, H 23, Cl 13.6, N 10.8, P 11.9%;
C 18.6, H 23, Ci 15.2, N 10.7, P 11.9%. 34 oil ^d ) Calculated...
found C 25.0, H 3.7, N 11.7, P 12.9%;
C 27.4, H 3.9, N 11.8, P 123%. 70 Ul e) Calculated...
found C 28.4, H 43, N 11.0, P12%;
C 29.2, H 4.4, N 11.4, P 12.3%. 87 oil i) Calculated...
found C 28.4, H 43, P 12%;
C28 _V T, H 4.3, P 12.4%. 70 oil G) Calculated...
found C 31.3, H 4.9, N 10.4, P 11.5%;
C 32.2, H 5.0, N 10.9, P 12.2%. 84 H) Calculated...
found C 333, H 5.2, NIl ₁ I, P 12.3%:
C 32.6, H 5.1, N 10.2, P 12.4%.

Claims (1)

Patent claims: 1. 1 ^, 5-thiadiazolyl-phosphoric acid ester der general formula X OR ¹ Ο —Ρ N
\ new active ingredients also have a strong vapor phase and translaminar activity. The latter makes them particularly suitable for combating insects in fruit crops, when the infestation occurs on the underside of the leaves, but the protective agent on the The top of the sheet is applied. The compounds according to the invention are produced in a manner known per se by reacting a phenol the general formula OR ²