DE1793502B2 - 2-methyl-5,6-dihydropyran-3-carboxylic acid anilides and crop protection agents containing these compounds - Google Patents

Description

Il

CH ₃

(D

CH,

(I)

represents, which are each in the meta, ortho or para position of the benzene nucleus, correspond.

The invention also relates to crop protection agents containing the compounds of the general Formula I.

It is known that compounds of a similar constitution as 2 _r 3-dihydro-5-carboxanilido-6-methyl-1,4-oxathiin (II) and 2,3-dihydro-5-carboxanilido-6-methyll, 4-oxathiin- 4-dioxide (III) have fungicidal activity (cf. US Pat. No. 3,249,499 and Belgian Pat. No. 6,79,984, pages 19 and 29).

wherein R represents a methyl group or a methoxy group, each of which is meta-, ortho- or para position of the benzene nucleus, correspond.

2. Plant protection agents, characterized by a content of 2-methyl-5,6-dihydropyran-3-carboxylic acid anilides of the general formula I according to claim I in addition to customary inert carriers.

The subject of patent 16 68 899 is 2-methyl-S.b-dihydropyranO-carboxylic acid anilide the formula

and pesticides, characterized by a Content of 2-methyl-5,6-dihydropyran-.3-carboxylic acid anilide in addition to the usual inert carriers.

The invention relates to a modification of the compound of patent! 6 68 899, which is characterized is that the 2-methyl-5,6-dihydropyran-3-carboxylic acid anilide is substituted by a radical R in the manner. that the 2-methyl-5,6-dihydropyran-3-carboxylic acid anilides of the general formula I.

, i
C.

(ID

: h ₃

(ΙΠ)

wherein K is a methyl group or a methoxy group The known compound (II) has a good action against types of aviation fire, but only weak systemic Effect against rust diseases. The known compound (III) has good systemic and pickling effects against rust diseases, but proves to be inadequate in the fight against flying scorch diseases.

The compounds of the formula I according to the invention are the known compound (II) with regard to the systeinic effect and the pickling effect, the known compound (III) with regard to the effect Airborne fire fighting is surprisingly superior, as shown in Tables I to III of the experiments emerges. The 2-methyl-5,6-dihydropyran-3-carboxylic acid anilides of the general formula I are thereby produced that either 2-methyl-5,6-dihydropyran-3-carboxylic acid is produced in a manner known per se with a chlorinating agent to give 2-methyl-5,6-dihydropyran-3-carboxylic acid chloride and this with an appropriately substituted aniline in the presence of an inorganic or tertiary Omani base converts, or that 2-methyl-5,6-dihydropyran-3-carbric acid with an appropriately substituted phenyl isocyanate reacts at an elevated temperature.

Phosphorus trichloride is preferably used as the chlorinating agent; phosphorus pentachloride, thionyl chloride and phosphorus oxychloride are also suitable. The chlorination is carried out at temperatures between -20 ⁰ C and + 100 ⁰ C; preferred is a temperature range between 0 ⁰ C and 30 ° C.

The chlorination is expediently carried out in an inert solvent such as carbon tetrachloride, carbon form, Methylene chloride, ethylene chloride, toluene or benzene carried out.

The reaction of the acid chloride with the aniline in question substituted in the benzene nucleus is described in Carried out in the presence of an inorganic or tertiary organic base. As inorganic bases caustic soda and potassium hydroxide are primarily used. As tertiary organic bases can

Triethylamine, dimethylaniline or pyridine and their Homologues are used. An excess of the substituted aromatic amine can also be used.

The reaction of the 2-methyl-5,6-dihydropyran-3-carboxylic acid with the corresponding phenyl isocyanate at temperatures between 8O ⁰ C and 180 ° C, preferably between 140 ⁰ C and 170 ⁰ C. After the reaction it is expedient that To free the reaction product from excess phenyl isocyanate by washing with an inert solvent such as carbon tetrachloride or gasoline.

The 2-methyl-5,6-dihydropyran-3-carboxylic acid anilides according to the invention are used as active ingredients in pesticides in addition to the usual inert carriers usable, especially as fungicides. They are particularly effective against rust and smut fungi on cereals, z. B. against wheat yellow rust and wheat brown rust, air fire, stone fire and soil fungi, such as Rhizoctonia. As a fungicide, it can be used both in crop protection and in stored product protection. μ

The compounds according to the invention can be used in customary mixtures with solid or liquid inert carriers, with adhesives, wetting agents, dispersing agents and Grinding aids can be used as wettable powders, emulsions, suspensions, dusts or granulates. You:> 5 can be mixed with other pesticides, with which they are compatible mixtures form.

Mineral substances such as aluminum silicates, clays, kaolin, chalks, kieselkreidci, talc, kieselguhr or hydrated silica, or preparations of these mineral substances with special additives, e.g. B. Chalk greased with sodium stearate. As Trägersto ^rf e for liquid preparations may contain all the usual and geeigne-; i5 th solvent, for example toluene, xylene, diacetone alcohol, cyclohexanone, isophorone, gasoline, paraffin oils, dioxane, dimethylformamide, dimethyl sulfoxide, ethyl acetate, butyl acetate, tetrahydrofuran, chlorobenzene are used.

Glue-like cellulose products or polyvinyl alcohols can be used as adhesives.

As wetting agents, all suitable emulsifiers such as oxyethylated alkylphenols, salts of aryl or Alkylarylsulfonic acids, salts of methyltaurine, salts of phenylkogasinsulfonic acids or soaps are used will.

Cell pitch (salts of lignosulphonic acid), salts of naphthalenesulphonic acid can be used as dispersants and, under certain circumstances, hydrated silicas or even kieselguhr can be used.

Suitable inorganic or organic salts such as sodium sulfate, ammonium sulfate, Sodium carbonate, sodium bicarbonate, sodium thiosulfate, sodium stearate or sodium acetate are used will.

example

(rO

0.1 mol of 2-methyl-5,6-dihydropyran-3-carboxylic acid is suspended in 25 ml of ethylene chloride, 0.05 mol of phosphorus trichloride is added and the mixture is left to stand for 1.5 hours at room temperature with exclusion of moisture. After separating off the phosphorous acid. 1.5, which forms the lower liquid layer in the reaction mixture, the solvent is distilled off under reduced pressure. The crude acid chloride obtained is added ^{dropwise at 0 °} C. to a solution of 0.1 mol of the corresponding aromatic amine substituted in the benzene ring in 0.12 mol of pyridine and 100 ml of benzene. After standing for one hour at room temperature, the reaction mixture is poured into water, the organic Phase washed with dilute hydrochloric acid and water and the solvent was distilled off.

In this way the following connections were made:

a) Using m-toluidine 2-methyl-5,6-

dihydropyran-3-carboxylic acid (m-methylanilide), yield 78% of theory (based on the Carboxylic acid); Melting point 96.5-97.5 ° C.

b) Using o-toluidine, 2-methyl-5,6-diydropyran-3-carboxylic acid (o-methylanilide), yield 75% of theory; Melting point 128 to 128.5 ⁰ C.

c) Using p-toluidine 2-methyl-5, o-dihydropyran-3-carboxylic acid (p-methylanilide), yield 80% of theory; Melting point i25-i26 ^? C.

d) Using m-anisidine 2-methyl-5,6-

dihydropyran-3-carboxylic acid-m-methoxyaniIide, yield 73% of theory; Melting point 104-105 ⁰ C.

e) Using o-anisidine 2-methyl-5,6-dihydropyran-3-carbo (i-acid- (o-methoxyanilide), Yield 78% of theory; Melting point 131-132 ° C.

f) Using p-anisidine-2-methyl-5,6-

dihydropyran-3-carboxylic acid (p-methoxyanilide), yield 79% of theory; Melting point 155-156 ° C.

Attempt 1

Wheat plants grown in pots in the greenhouse became the two-leaf stage with the compounds according to the invention listed below in active compound application rates of 400, 200, 100 and 50 mg / 1 spray liquid treated:

(A) = 2-methyl-5,6-dihydropyran-3-carboxylic acid

(m-methylanilide)

(B) = 2-methyl-5,6-dihydropyran-3-carboxylic acid

(o-methy! anilide)

(C) = 2-methyl-5,6-dihydropyran-3-carboxylic acid

(p-methylanilide)

(D) = 2-methyl-5,6-dihydropyran-3-carboxylic acid

(m-methoxyanilide)

(E) - 2-methyl-5,6-dihydropyran-3-carboxylic acid

(o-methoxyanilide)

(F) = 2-methyl-5,6-dihydropyran-J-carboxylic acid

(p-methoxyanilide).

Those known as fungicides were used in the same way and with the same active ingredient application rates Links:

(G) = 2,3-dihydro-5-carboxanilido-6-methyl-

1,4-oxathiin and

(H) = zinc ethylene bis-dithiocarbamate used. as untreated controls were another number of plants with tap water without Treated active ingredients.

5 days after the treatment both became nimble! th leaves cut off at the base of the stem. After ί Weeks the newly overgrown leaves were with

of a spore suspension of Wheat Black Rose strong Table II infected, then placed in the humidity chamber for 12 hours and then in the greenhouse The incidence of the disease was assessed three weeks after the infection.

As can be seen from Table I below, the compounds (A) - (F) according to the invention an excellent systemic effect superior to the known comparative compounds (G) and (H) against wheat rust (The comparison agent (H) showed no systemic effect.)

Table I.

Compound% yellow rust infestation of wheat plants after treatment with g of active ingredient per 100 kg of seeds

200 100 50

Compound% black rust fall from wheat plants after treatment with mg of active ingredient
per liter of spray liquid

400 200 100 50

20th

(A) 0 0 0 5

(B) 0 0 0 3

(C) 0 15 23 35

(D) 0 0 3 10

(E) 0 0 10 15

(F) 0 0 15 25

(G) 10 35 60 100 (H) 100 100 100 100 Untreated 100 100 100 100

30th

Attempt 2

Wheat seeds of the variety "Heine VII" were with the compounds (A) - (F) according to the invention in the Application rates of 200, 100 and 50 g of active ingredient per 100 kg of seed for 10 minutes in a dressing drum pickled in the usual way. For comparison, wheat seeds were compared with the known compound (G) in the same way Treated wisely. 14 days after the treatment, the Saatg-it was sown and the wheat plants after Emergence in the three- to four-leaf stage infected with spores of wheat yellow rust.

4 weeks after infection, the plants were examined for rust attack and the degree of attack was determined.

Table II below shows that the invention Compounds (A) - (F) have a very good systemic effect against wheat yellow rust in the pickling process own. The comparison compound (G), on the other hand, does not show any under the conditions mentioned Effect.

0
0
0
0
0
0
100

Untreated 100

10

15th

15th

23

100

100

15th

31

35

20th

41

48

100

100

Attempt 3

Oat seed gui of the variety »Flämingstreue« became strong with spores of oat brandy (Ustilage avenae) infected. The infected seed was treated with the compounds (A) - (F) according to the invention in application quantities of 1OtD, 50 and 25 g of active ingredient per 100 kg of seed for 10 minutes in a dressing drum in Dressed in the usual way For comparison, seeds were mixed with the known 23-dihydro-5-caιbonanilido-6-methyl-1,4-oxathiin-4-dioxide (III) treated with the same application rates. After 14 days, the seeds were sown. After the panicles were formed, the Plants examined for infestation with oat blight.

From Table III below it can be seen that the compounds (A) - (F) according to the invention have a significantly better action against flying scorch than the comparative agent (III).

Table HI

link % Oat burns after 50 25th Treatment with g active ingredient per 0 0 100 kg of seeds 0 0 100 0 5 (A) 0 0 3 (B) 0 5 15th (C) 0 0 5 (D) 0 12th 35 (E) 0 71 64 (F) 0 (III) 0 Untreated 68

Claims (1)

Patent claims: I. Modification of 2-methyl-5,6-dihydropyran-3-carboxylic acid anilide the formula C-NH- CH ₃ according to patent 16 68 899, characterized in that that the 2-methyl-5,6-dihydropyran-3-carboxylic acid anilide is substituted by a radical R in such a way that the 2-methyl-5,6-dihydropyran-3-carboxylic acid anilides of the general formula I.