DE2513788C3 - Substituted furan-2-carboxylic acid anilides and processes for their preparation and fungicidal agents containing these compounds - Google Patents

Description

CH ₃

in which R is a hydrogen atom or a methyl group

2. Process for the preparation of the compounds according to claim 1, characterized in that a compound of the general formula II is used in a manner known per se

<^ O) ^ NH — CH-COOCH ₃ (II)

CH ₃

in which R is a hydrogen atom or a methyl group, with the furan (2) carboxylic acid, an acid halide, acid anhydride, or an ester or amide thereof, acylated

3. Fungicidal agent, characterized in that it is a compound according to claim 1 as an active ingredient Contains together with usual carriers and / or application-promoting additives.

40

The invention relates to substituted furan-2-carboxylic acid anilides of the general formula I.

³ CH-COOCH ₃

(i) Pesticides developed resistance to a greater extent to have.

There is therefore an urgent need for microbicides which are compatible with crop plants and destroy their direct parasites.

Such crops are, for example, cereals, corn, rice, vegetables, sugar beets, soy, peanuts, Fruit trees, ornamental plants, but above all vines, hops, cucumber plants (cucumbers, pumpkins, melons), Solanaceae such as potatoes, tobacco and tomatoes, as well as banana, cocoa and natural rubber plants.

It has now been found, surprisingly, that with the compounds of the above general,] Formula I on plants or parts of plants (fruits, flowers, foliage, stems, tubers, roots) of these and related crops, the fungi that occur can be contained or destroyed, whereby Even parts of plants that grow later are spared from such fungi. The active ingredients are against that effective phytopathogenic fungi belonging to the following classes: Asomycetes (e.g. Erysiphaceae); Basidiomycetes, especially rust fungi; Fungi imperfecti; but then especially against those of the class of Phycomycetes belonging to Oomycetes such as Phytophthora, Peronospora, Pseudoperonospora, Pythium or Plasmopara. In addition, the connections work of formula I systemic.

They can also be used as a dressing agent for the treatment of seeds (fruits, tubers, grains) and plant cuttings used to protect against fungal infections and against phytopathogenic fungi that occur in the soil will.

The substituted furan-2-carboxylic acid anilides of the formula I represent microbicidal active ingredients which usual commercial preparations in their field of application and known analog compounds that are based on the in the same area of application, are clearly superior, as from the comparative tests carried out emerges.

The 2,5-dimethyl-furan-3-carboxylic acid anilide known from DT-AS 17 68 686 and its corresponding 2'-Toluidid are such a plant fungicide. The limits of action of this type of compound can be seen from the comparative experiments.

In DT-OS 20 06 471 a large number of furan-3-carbonamides are used as fungicides and insecticides specified. In particular, their effectiveness against rust fungi is emphasized. The structurally closest comparable or connections disclosed as most effective are also used for comparison.

The substituted furan-2-carboxylic acid anilides of the formula I are prepared by in per se known way a compound of the general formula II

55

in which R represents a hydrogen atom or a methyl group, and processes for producing the same Compounds, and also fungicidal agents, which contain these compounds as active ingredients.

Bacterial and fungal diseases in crops are favored by two factors In the case of plant breeding, the aim is primarily to increase yield and improve quality. Often however, part of the plant's natural resistance to parasites is lost. To the Second, experience has shown that bacteria and harmful fungi over the years against the known

CH,
NH-CH- COOCH., (M)

in which R is a hydrogen atom or a methyl group means with the furan (2) carboxylic acid, an acid halide, acid anhydride or an ester or amide the same, acylated.

Furthermore, the compounds of the formula I can also be prepared from an acylanilide in a manner known per se

general formula III

R CH ₃

in which R denotes a hydrogen atom or a methyl group can be produced by this with butyl-lithium or Na hydride is converted into the corresponding alkali salt, which is then mixed with a methyl halopropionate to the compound of formula I is reacted, or the acylanilide III is with an ac-halopropionic acid methyl ester in the presence an alkali carbonate such as K2CO3 as proton acceptor, preferably with the addition of catalytic amounts of alkali iodide, e.g. B. K] implemented

The acid chloride is preferably used as the acid halide or acid bromide is used and the halogen atom in the-halopropionic acid methyl ester is preferably represents a chlorine or bromine atom.

The reactions can be inert to the reactants in the presence or absence Solvents or diluents are carried out. Aliphatic or aromatic are suitable for this Hydrocarbons such as benzene, toluene, xylenes, petroleum ether; halogenated hydrocarbons such as Chlorobenzene, methylene chloride, ethylene chloride, chloroform; Ether and ethereal compounds such as dialkyl ethers, Dioxane, tetrahydrofuran; Nitriles such as acetonitrile; Ν, Ν-dialyzed amides such as dimethylformamide; Dimethyl sulfoxide, Ketones such as methyl ethyl ketone and mixtures of such solvents with one another.

The reaction temperatures are between 0 ° and 180 ⁰ C, preferably between 20 ° and 120 °. In some cases, the use of acid-binding agents or condensation agents is advantageous. Tertiary amines such as trialkylamines (e.g. triethylamine), pyridine and pyridine bases, or inorganic bases such as the oxides and hydroxides, hydrogen carbonates and carbonates of alkali and alkaline earth metals and sodium acetate are suitable as such. An excess of the respective aniline derivative of the formula II can also serve as an acid-binding agent. It is also possible to work without acid-binding agents, in which case nitrogen may be passed through to drive off the hydrogen halide formed. In other cases it is very advantageous to add dimethylformamide as a reaction catalyst

The starting compounds of the formula II can be prepared by the methods described in the Journal of Organic Chemistry, Vol. 30, p. 4101 [1965], according to Tetrahedron 1967, p. 487 or p. 493.

The compounds of general formula I have an asymmetric propionic ester chain Carbon atom and can be split into the optical antipodes in the usual way. Here owns the enantiomeric D-form the stronger microbicidal effect, so that compounds with the D-configuration are preferred. These D-shapes have a negative angle of rotation in ethanol or acetone.

For the preparation of pure optical D-antipodes fts of the compounds of general formula I is furanoyliert the optical D-configuration of the ester of the formula II in the manner indicated. In addition to the optical isomerism in the case of R = CH3, there is an atropisomerism around the

/
Phenyl-N axis

(111) ⁵ \

due to the steric hindrance of the three residues on the N atom of the trimethylaniline. Provided If no specific synthesis is carried out to isolate pure isomers, compound no. 2 (cf. Example 2) in the preparation as a mixture of 4 isomers. The more favorable fungicidal effect of the enanliomeric D-form (compared to D, L-form or L-form) is retained and is not significantly influenced by atropisomerism

The D-form of the ester of the formula II to be used as starting material has been obtained by that a racemic compound of the formula IV

CH ₃
NH-CH-COOH (IV)

(R = H or CH ₃ )

is reacted in a manner known per se with an N-containing optically active base such as -phenylethylamine to give the corresponding salt and by fractional crystallization of the salt and subsequent release of the acid of the formula IV enriched with the optical D antipode and optionally repetition (also multiple repetitions) the salt formation, crystallization and release of the Λ-anilinopropionic acid of the formula IV first gradually wins the pure D-form, from which then in the usual way, for. B. in the presence of HCl or H ₂ SO ₄ , the ester in question is obtained with methanol.

Instead of fractional crystallization, the enantiomeric D-form of the formula IV can also be passed through Replacement of the hydroxyl group in the naturally occurring L (+) lactic acid for halogen and Further reaction of this product with reversal of configuration with the desired 2,6-dimethylaniline or Win 2,3,6-trimethylaniIin.

CH-COOCH ₃

(Connection no. 1)

N- (1'-methoxycarbonylethyl) -N- (furan- (2 ") - carbonyl) -2,6-dimethylaniline.

To 18.2 g of N- (l'-methoxycarbonyiethyl) -2,6-dimethylaniline in 10 ml of anhydrous toluene and 0.2 ml of dimethylformamide were 12.6 g with stirring Furan-2-carboxylic acid chloride was added dropwise. After the mildly exothermic reaction had subsided the mixture is refluxed for five hours and

the hydrogen chloride formed is completely eliminated by passing nitrogen through it Solvent was distilled in vacuo. The product which passed over at a boiling point of 0.06 166-168 ° C. solidified when standing. X-ray powder diagrams show that the compound is polymorphic. After recrystallization from ethyl acetate / petroleum ether, it is obtained a uniformly crystalline product; F. 85 - 86 ° C.

Yield: 72.7% of theory.

If the starting material used in the above approach is the enantiomeric D configuration of N- (r-methoxycarbonylethyl) -2,6-dimethylaniline of the formula

O> -NH-CH-COOCH ₃

CH ₃
(D) shape

Γ »? = +29.8 ± 0.5 °; C = 1.52% w / v in methanol]

the D-form of N- (l'-methoxycarbonylethyl) -N- (furan- (2 ") - carbonyl) -2,6-dimethylaniline is thus obtained with otherwise the same procedure the formula

from 102 to 103 ° C (α)? = -47.0 ± 0.7 °; C = 1.73% w / v in acetone (compound 1 a)

(Connection no.2)

N- (1'-methoxycarbonyl-ethyl) -N- (furan (2 ") -carbonyl) -2,3,6-trimethylaniline.

A suspension of 51.5 g (0.382 mol) 2,3,6-trimethylaniline, 35.3 g NaHCO ₃ and 126 ml (1.15 mol) methyl 2-bromopropionate is stirred for 6 hours at a bath temperature of 130 °, then cooled , filtered from the salt and distilled: 67.3 g of methyl oc- (2,3,6-trimethylanilino) propionate (bp. 9 144 ° - 146 ° C).

A suspension of 33.5 g (0.152 mol) of methyl (2,3,6-trimethylanilino) propionate and 18 g (0.17 mol) of soda in 200 ml of absolute benzene is added dropwise with 16.7 ml (0, 17 mol) of furan-2-carboxylic acid chloride at 60 -70 ⁰ C and the mixture then kept still for 4 h. at this temperature. After cooling, filtering and concentrating the filtrate, the residue is recrystallized from isopropyl ether. One receives in 86% yield N- (I '-methoxycarbonyl-ethylJ-N-Jfuran-

(2 ") - carbonyl) -2,3,6-trimethylaniline with a temperature of 98-102 ° C.

Example 3

N- (1'-methoxycarbonyl-ethyl) -N- (furan (2 ") -carbonyI) -2,6-dimethylaniline.

ίο It is made from 2.4 g (0.055 mol) of 55% sodium hydride oil dispersion and 25 ml of tetrahydrofuran prepare a suspension. This is added dropwise at room temperature 10.75 g (0.05 mol) of furan-2-carboxylic acid-2 ', 6'-dimethylanilide dissolved in 125 ml of tetrahydrofuran, F.

125 -128 ° C, which is obtained by reacting 2,6-dimethylaniline with z. B. 2-furanoyl chloride has won The reaction mixture is then 30 min. At normal Temperature and stirred for a further 30 min. At 45 ° C. After cooling, 9.2 g (0.055 Mol) 2-bromopropionate, dissolved in 10 ml of tetrahydrofuran, is added dropwise. Then, for 1 hour Stirred at normal temperature and refluxed for 24 hours. After cooling, it is filtered and the filtrate concentrated on a rotary evaporator The remaining as residue N- (I '-Methoxycarbo-

nyl-ethyl) -N- (furan- (2 ") - carbonyl) -2,6-dimethylaniline
is recrystallized from ether / petroleum ether; Melting point 82-84 ° C. Yield: 62% of theory.

The compounds of the formula I can be used to broaden their spectrum of activity with others suitable pesticidal or plant growth-promoting active ingredients are used.

The compounds of the formula I can be used alone or together with suitable carriers and / or other aggregates can be used. Suitable carriers and aggregates can be solid or liquid and correspond to the substances commonly used in formulation technology, such as B. natural or regenerated mineral substances, solvents, dispersants, wetting agents, adhesives, thickeners, binders or fertilizers.

The content of active ingredient in commercial products is between 0.1 and 90%.

Suitable administration forms (the weight percentages in brackets representing advantageous amounts of the active ingredient) are, for example:
solid forms of processing such as dust and grit (up to 10%); Granules, coated granules, impregnation granules and homogeneous granules (1 to 80%);

and liquid work-up forms, for example

a) Active substance concentrates dispersible in water:
Wettable powders and pastes (25-90% in the commercial pack, 0.01 to 15% in the ready-to-use solution);

Emulsion and solution concentrates (10 to 50%; 0.01 to 15% in ready-to-use solution);

b) solutions (0.1 to 20%);

Some of these application forms and their formulation are described below;

Dust

The following substances are used to produce a) 5% and b) 2% dust:

a) 5 parts 5 parts connection no. 2
95 parts of talc;

b) 2 parts connection no. 1

1 part of highly dispersed silica,
97 parts of talc;

The compounds in question are mixed and ground with the carriers and can be used in this form can be dusted for application.

granules

The following substances are used to produce 5% granules:

5 parts of compound no. 1, 0.25 part of epichlorohydrin,

0.25 parts of cetyl polyglycol ether, 3.50 parts of polyethylene glycol,
91 parts of kaolin (grain size 0.3-0.8 mm).

The compound in question is mixed with epichlorohydrin and dissolved with 6 parts of acetone, then is Polyethylene glycol and cetyl polyglycol ether added. The solution obtained is sprayed onto kaolin, and then the acetone is evaporated in vacuo. Such microgranules are advantageous used to control soil fungi.

Wettable powder

For the preparation of a a) 70 ⁰ / o b) 40% c), and d) 25 ° / o e) a 10% wettable powder The following constituents are used:

15th

19.5 parts Champagne chalk, 28.1 parts Kaolin; 25 parts Connection no. 2, 2.5 parts Isooctylphenoxy-polyoxyethylene-etha nol, 1.7 parts Champagne chalk / Hydroxyäthylcel- lulose mixture (l: 1), 8.3 parts Sodium aluminum silicate, 16.5 parts Kieselguhr, 46 parts Kaolin; 10 parts Compound No. 1 a (D-Form), 3 parts Mixture of the sodium salts of sown saturated fatty alcohol sulfates, 5 parts Naphthalenesulfonic acid / formaldehyde Condensate, 82 parts Kaolin;

a) 70 parts

5 parts
3 parts

b)

c)

10 parts

12 parts

40 parts

5 parts

Part 1

54 pieces
25 parts
4.5 parts
1.9 parts

1.5 parts
19.5 parts

Connection A

(D) -form of N- (1'-methoxycarbonyl-ethyl) -N- [furan- (2 ") carbonyl] -2,6- dimethylaniline (compound no. la), sodium dibutylnaphthylsulfonate, Naphthalenesulfonic Acids-Phenolsulfone-

acid-formaldehyde condensate 3: 2: 1,
Kaolin,

Champagne chalk; Compound No. 2, lignin sulfonic acid sodium salt, Dibutylnaphthalene sulfonic acid sodium salt,

Silica;
Compound No. 1, calcium lignin sulfonate, champagne chalk / hydroxyethyl cellulose mixture (1: 1), sodium dibutyl naphthalene sulfonate, silica,

NH-CO-

35 The compounds in question are intimately mixed with the aggregates in mixers and ground on appropriate mills and rollers. The wettable powder obtained has excellent wettability and suspension properties, which can be diluted with water to form suspensions of any desired concentration and, in particular, can be used for foliar application.

Emulsifiable concentrates

The following substances are used to produce a 25% emulsifiable concentrate:
25 parts connection no. 1,
2.5 parts epoxidized vegetable oil,
10 parts of an alkylarylsulfonate / fatty alcohol poly-

glycol ether mixture,
5 parts of dimethylformamide,
57.5 parts of xylene.

Any desired emulsions can be obtained from such a concentrate by diluting it with water Concentration can be produced, which are particularly suitable for foliar application.

Attempt I.
Action against Phytophthora infestans on tomatoes

The following known compounds were used as comparison substances:

(DT-OS 2006471, pp. 13 and 18)

CH ₃

CH ₃ O

CH ₃

Compound BH ₃ C- <O> -NH-CO -π π

Compound C

(DT-OS 2006471, p. 13)

CH ₃ O

NH - CO

(DT-OS 2006471, p. 13)

CH, O

Connection D

Connection E

A fungal infestation of over 50% marks the relevant active ingredient used (= AS) as for practical purposes ineffective. There is no further differentiation.

a) Curative effect

Tomato plants of the "Red Gnome" variety are grown with a zoospore suspension after three weeks of cultivation of the mushroom sprayed and incubated in a cabin at 18 to 20 ° and saturated humidity. Interruption of humidification after 24 hours. After the plants have dried, they are covered with a Sprayed broth containing the compound to be tested, formulated as a wettable powder, in one of the specified Contains test concentrations. After the spray coating has dried on, the plants are back in the Damp cabin set up for 4 days. Number and size of the typical ones that occur after this time Leaf spots are the yardstick for assessing the effectiveness of the substances tested. Infected but untreated control plants are used as a reference value.

Checked
connection

Test

concentration
(% AS)

Fungal attack

A.
B.
C.
D.
E.

0.06
0.02
0.06
0.02

0.06
0.02
0.06
0.02
0.06
0.02
0.06
0.02
0.06
0.02

5-10
5-10
5-10
5-20

20-40
over 50
20-40
20-40
over 50
over 50
over 50
over 50
over 50
over 50

b) Preventive-systemic effect

The compound to be tested formulated as a wettable powder is potted in the form of a spray mixture on the top soil layer of 3-week-olds Tomato plants of the variety »Roter Gnom« given so that a concentration of 0.006% in the root area or 0.002% of the active ingredient (based on the soil volume) is present. Care is taken that the The spray liquid does not come into contact with the above-ground parts of the plant. After 48 hours the treated plants infected with a sporangia suspension of the fungus Assessment of the fungal attack takes place after incubation of the infected plants for 5 days at 20 ° and saturated humidity

(DT-OS 1768 686, example 1)

(DT-OS 2006471, p. 19, fourth connection)

speed. The number and size of the leaf spots that occurred at this point in time serve as a measure of the Effect of the tested substances in comparison to infected but untreated control plants.

ι.s checked
connection

Test

Concentralization
(% AS)

Fungal attack

( ⁰ A)

No. 3 ° D. I 0.006 5-10 0.002 5-10 No. E. 2 0.006 5-10 0.002 5-10 25 A .15 *) 0.006 20-40 *) **) 0.002 20-40 *) B. 0.006 20-40 0.002 over 50 C. 0.006 over 50**) 0.002 over 50*) 0.006 20-40 0.002 over 50 0.006 over 50 0.002 over 50 = slight phytotoxicity = unsustainable phytotoxicity

Experiment II

Action against Plasmopara viticola (Bert, et Curt.)
(Berl. Et DeToni) on vines

a) Residual preventive effect

Vine cuttings of the "Chasselas" variety were grown in the greenhouse. In the 10-leaf stage were 3 plants with a compound to be tested prepared from the compound to be tested, formulated as a wettable powder Sprinkled broth. After the spray coating had dried on, the plants were on the underside of the leaves with the spore suspension of the fungus evenly infected.

The plants were then kept in a humid chamber for 8 days. After that time showed clear symptoms of disease on the control plants. The number and size of the infection sites the treated plants served as an evaluation standard for the effectiveness of the substances tested.

The prior art compounds mentioned in Experiment I were used for comparison.

60 tested
connection

Test

concentration
(% AS)

Fungal attack

number 1
No. 2

0.02 0-5 0.006 0-5 0.02 0-5

11th

(icprüi'tc
connection

Λ
I)
C.
D.
E.

l'rül-

Κοιν duration

(% AS)

0.006

0.02

0.006

0.02

0.006

0.02

0.006

0.02

0.006

0.02

0.006

I'il / belall

0-5

20-40 over 20-40 over over over over over over over

Checked concentration Fungal attack Connection no. 1 0.05% 0-5% 0.02% 0-5% 1 a 0.02% 0-5% 2 0.05% 0-5% 0.02% 0-5%

25th

b)! Curative effect

Vine cuttings of the »Chasselas« variety were grown in the greenhouse and at the 10-leaf stage infected with a spore suspension of Plasmopara viticola on the underside of the leaf. After 24 hours in In the humid cabin, the plants were sprayed with an active ingredient mixture made from a wettable powder connection to be tested had been established. The plants were then kept in for 7 days kept in the humid cabin. After this time, the symptoms of the disease appeared on the control plants. The number and size of the infection sites on the treated plants were used as a benchmark for the effectiveness of the tested substances.

.15

40

Attempt 111

Action against Pythium debaryanum
on Beta vulgaris (sugar beet)

a) Effect after application to the soil

The mushroom is cultivated on sterile oat kernels and added to a soil / sand mixture. The infected one Soil is filled into flower pots and sown with sugar beet seeds. Immediately after sowing the Test preparations formulated as wettable powders poured over the earth as aqueous suspensions (0.002% the connection to be tested, based on the volume of the earth).

The pots are then placed in a greenhouse at 20-24 ° C. for 2-3 weeks. The earth will kept evenly moist by lightly spraying with water. When evaluating the tests, the The emergence of the sugar beet plants and the proportion of healthy and diseased plants are determined.

b) Effect after pickling application

The mushroom is cultivated on sterile oat kernels and added to a mixture of soil and sand. The soil infected in this way is filled into flower pots and sown with sugar beet seeds which have been dressed with the test preparations formulated as dressing powder (0.1% of the compound to be tested, based on the weight of the seeds). The sown pots are placed for 2-3 weeks in a greenhouse at 20-24 ⁰ C. The earth is kept evenly moist by lightly discussing it with water. During the evaluation, the emergence of the sugar beet plants and the proportion of healthy and diseased plants are determined.

Under the conditions of both experiment a) and b) yeast after treatment with one of the Compounds No. 1,1a or 2 over 85% sugar beet plants and had a uniformly healthy one Look. In the case of the untreated control, fewer than 20% of the plants were partially sickly Look on.

Claims (1)

Patent claims: 1. Substituted furan-2-carboxylic acid anilides der general formula I. CH ₃ CH-COOCH ₃ (I), 0