DE2546271A1 - Fungicides contg. substd. cyano-acetanilide derivs. - esp. as seed dressings against Helminthosporium gramineum of barley - Google Patents

Abstract

New fungicidal agents contain a cpd. of formula (I) in combination with usual formulation adjuvants. In formula (I), R1 is Cl, Br, I, CF3, -O-CCl=CHCl, -O-CR2-CHHal2 (Hal=Cl and/or F), -O-CCl=CCl2, NO2, COC6H5, CONHC6H5, NHCOCH3, or CH3; R2 is H, Cl, Br or CF3; and R3 is H or Cl. Pref., 1 of R1, R2, and R3 is Cl, Br or CF3, the remainder being H. (I) show interesting fungicidal activity, e.g. against Erysiphe graminis, Plasmopara viticola, Phytophthora infestans and Puccinia triticina. They can be used in usual formulations such as wettable powders, emulsion concentrates, dispersions or ULV concentrates. However, (I) are partic. useful as seed dressings, esp. for barley, due to their good activity against Helminthosporium gramineum. Specific (I) include 2-cyano-3',5'-bis(trifluoromethyl)-acetanilide.

Description

Fungicides

Cyanoacetic anilides substituted on the phenyl ring are larger Number described in GB-PS 930,808 as anti-tuberculous agents.

It is also known that several compounds of this type cause the Hill reaction although inhibit, but to such an extent that they cannot be used as herbicides g A. Baruffini, p. Borgna and G. Pagani, Pharmaco, Ed. Sci. 22 (1) 769 (19677.

Furthermore, cyanoacetic anilides are in DT-OS 1.900.947 as Described precursors for growth regulators and / or herbicides.

It has now surprisingly been found that representatives of this class of substances have an interesting fungicidal effect.

The invention therefore relates to fungicidal agents which are characterized by a content of a compound of the general formula in which R1 is Cl, Br, I, CF3, -O-CCl = CClH, -O-CF2-CHal2H, -OCCl = CCl2, NO2, COC6H5, CONHC6H5, NHCOCH3, CH3 with Hal = Cl and / or F; R² is H, Cl, Br or CF3; and R³ denotes H or Cl, in addition to customary formulation auxiliaries.

Those compounds are preferred in which at least one of the R1, R2 or R3 is chlorine, bromine or CF3 and the others are hydrogen.

Some of the compounds of the formula I are known, and some are not can be produced by known methods.

Such manufacturing processes are described, for example, in GB-PS 930,808; the most common method is the implementation of cyanoacetic ester + substituted aniline according to the following equation According to Comptes rendus 121, 189 (1895), such compounds can be prepared according to the following reaction scheme: Ar = subst. Phenyl The following table lists a number of known and new compounds in this group.

Tabel No. R1 R2 R3 m.p. (° C) 1 4-Cl HH 207 2 4-Br HH 198-200 3 4-NO2 HH 198-202 4 4-CO-C6H5 HH 193-195 5 3-Cl HH 137- 139 6 3-Br HH 144 7 3-JHH 146-148 8 3-CF3 HH 137-139 9 3-NO2 HH 161-162 10 3-OCF2CF2H HH 137-138 11 3-OCF2CFClH HH 122-124 12 3-OCCl = CHCl HH 164-166 13 3-CO-NH-C6H5 HH 231-233 14 2-Cl HH 121 15 2-CH3 3-Cl H 176 16 2-CH3 5-Cl H 188-189 17 2-Cl 5- CF3 H 144-145 18 2-Br 5-Br H 202-204 19 3-Cl 4-Cl H 169-170 20 3-Cl 5-Cl H 159-161 21 4-NHCOCH3 3-Cl 5-Cl 205- 206 22 3-CF3 5-CF3 H 137 23 3-Cl 4-Cl 5-Cl 203-205 24 3-OCF2CCl2H HH 123-125 For example, Fig. B. the compound 22 a good fungicidal action against Erysiphe graminis and other powdery mildew species, Plasmopara viticola, Phytophthora infestans and Puccinia triticina.

The compounds according to the invention can be in the usual forms Formulate as wettable powder, emulsion concentrate, dispersion and ULV concentrate and apply to the green plant.

However, the compounds according to the invention are particularly useful as seed dressings usable.

In this application form, * have compounds of the formula I in which at least one of the radicals R¹, R² or R³ is Cl, Br or CF3 and the others are hydrogen mean an excellent effect against Helminthosporium gramineum (streak disease the barley). *) in particular those subject of the invention are therefore also seed dressings, in particular for barley, which by a content of compounds of the formula I, in which the radicals R1, R2 and R3 have the meaning given above, in addition to the usual Formulation aids are marked.

To broaden the spectrum of activity, in particular to record from Ustilago nuda, next to Helminthosporlum gramineum the most important economically Harmful fungus of barley, it is expedient to combine the claimed compounds with a Ustilago-active component to be used together as a seed dressing agent.

The following are suitable as such: a) 5,6-Dihydro-2-methyl-1,4-oxathiine-3-carboxylic acid anilide (US Patent 3,249,499) b) 2,5-dimethyl-furan-3-carboxylic acid anilide (BE patent 734,808) c) 2,5-dimethyl-furan-3-carboxylic acid cyclohexylamide (DT-OS 2.019.535) d) 2-methyl-5,6-dihydro-4H-pyran-carboxylic acid-meta-ethoxy-anilide German patent application P 24 16 431.6) e) (Cj2Q0) -alkanesulfonic acid salts of benzimidazole carbamic acid methyl ester (DT-OS 2.320.529) .f) l-methoxycarbonyl-3-exo-endo-norbornylmethyl-s-hexahydrotriazino-benzimidazole (DT-OS 2.349.911) g) 2- (methoxycarbonylamino) benzimidazole The seed dressings according to the invention can contain the active substance alone or, preferably, in a mixture with one or more of the compounds a) to g) in a total concentration of 10 to 90% by weight, preferably 40 to 80% by weight. The remainder generally consists of one or more of the customary inert materials which, in a manner known per se, are intended to prevent the fungicidal ground material from baking together or to support its gate distribution over the seed. Talc, silica, kieselguhr or kaolin can preferably be used as such inert materials. The agents can be prepared in a manner known per se by grinding the components.

To achieve a sufficient effect, barley seeds are required for 100 kg 100-300 g of active ingredient, preferably 120-200 g, required; larger quantities are possible, but without any particular advantage. The ratio of the components from the formula I. to a) -in the mixture can vary in the range from 1: 2 to 2: 1.

The seeds are treated by intensive mixing of dressing agents and seeds, it can e.g. Dry pickling plants or mixing drums.

The treatment time varies with the intensity of the mixing.

In the usual systems, a period of 3 - 10 minutes is sufficient.

The combined pickling agents according to the invention have excellent properties Effect against both Helminthosporium gramineum and Ustilago nuda Effect that was previously only achievable with dressing agents containing Hg Comparative substances used in biological examples have the following chemical Constitution: A = manganese-ethylene-1,2-bis-dithiocarbamate B = commercial mercury preparation (1.75 $ Hg) (methoxyethyl-Hg-silicate) C = combination preparation of 5,6-dihydro-2-methyl-1,4-oxathiin-3-carboxanilide and methoxyethyl - mercury silicate.

Example I: Winter barley seeds naturally infected with Helminthosporium gramineum with a degree of infestation of 30% was with the compound 22 in concentrations of 200, 150, 100 and 75 g of active ingredient per 100 kg of seed dressed. The sowing took place In mid-November in such a way that 20 g of the dressed seeds are gropened in 2 m2 Parcels were created.

At the beginning of June, after the development of the typical leaf symptoms in the untreated, Helminthosporium infected plots, the evaluation of the Try. In the treated and untreated test members, both the with Helminthosporium gramineum as well as the healthy plants counted, the respective degree of infestation is determined and finally the degree of effectiveness is calculated, which is shown in Table I.

Table 1 Pickling agent efficiency in% with g preparation per according to 100 kg of seeds Example 400 300 250 200 150 Connection 22 100 100 100 - 100 98 Comparison means B - - - 100 - Comparison means C - - 100 - - Comparative means A - 75 - 55 50 untreated infected 0 0 0 0 0 plants The results show that the claimed compound still achieves the efficiency of at least 95% required for mercury-free Helminthosporium seed treatments with 150 g of preparation or 75 g of active ingredient per 100 kg of seed and is therefore suitable as a substitute for mercury preparations.

Example II: Naturally infected with Helminthosporium gramineum Spring barley seeds with an infestation degree of 15 0 were with the claimed Compounds 19 and 8 in concentrations of 200, 150 and 100 g of active ingredient per 100 kg of seed dressed. The seeds were sown in trays, which then placed in a greenhouse. Later both those with Helminthosporium gramineum infested plants as well as the healthy plants are counted, the respective The degree of infestation was determined and finally the degree of effectiveness was calculated (Table II).

Table II Pickling agent efficiency in% with g preparation according to per 100 kg of seeds Example 1 400 300 250 200 Connection 19 50% pickling agent Connection 8 50 added pickling agent 100 100 = 99 Comparative means A - 75 - 55 Comparative means B - - - 100 Comparative means C - - 100 untreated infected 0 0 0 0 plants The results in Table II show the superiority of the mercury-free claimed compounds over the comparative agent A. The claimed compounds achieve the degree of effectiveness of at least 95 required for Hg-free Helminthosporium dressing agents even with 100 g of active ingredient per 100 kg of seed.

Claims (3)

Claims 1 Fungicidal agents, characterized in that they contain a compound of the general formula in which R1 is C1, Br, J, CF3, -O-CCl = CClH, -O-CF2-CHal 2H, -OCCl = CC12, NO2, COC6H5, CONHC6H5, NHCOCH3 CH3 with Hal Cl and / or F; R² is H, Cl, Br or CF3; and R³ is H or Cl, in combination with customary formulation auxiliaries. 2) seed dressing, characterized by a compound content of the formula I in which at least one of the radicals is Cl, Br or CF3 and the others Mean hydrogen. 3) seed dressing according to claim 2, characterized by a Content of a compound of the formula I in which at least one of the radicals C1, Br or is CF3 and the others are hydrogen, in combination with one of or several of the compounds a) to g).