NO167663B - ANTIMICROBIAL COMPOUNDS. - Google Patents

Description

The present invention relates to new substituted 3-phenyl-4-cyano-pyrrole derivatives and mixtures for controlling harmful microorganisms, particularly phytopathogenic fungi.

The compounds according to this invention have the general formula:

where X has the following meaning:

hydrogen or CO-R^, wherein R^ is C^-Cs-alkyl which is unsubstituted or substituted by halogen or C1-C3-

alkoxy; or is C3-C6-alkenyl, C3-C6-alkynyl or C1-C6 alkoxy which is unsubstituted or substituted by halogen or C1-C3-alkoxy or C3-C6-alkenyloxy, C3-C6-cyclo-

alkyl or tetrahydrofur-2-yl.

Depending on the number of carbon atoms indicated, the alkyl itself

or as part of another substituent means for example the following group: methyl, ethyl, propyl, butyl, pentyl,

hexyl etc. and isomers thereof, e.g. isopropyl, isobutyl, tert-butyl, isopentyl etc. Haloalkyl is a mono- to perhalogenated alkyl substituent, e.g. CH2Cl, CHC12, CC13,

CH2Br, CHBr2, CBr3, CH2F, CHF2, CF3, CC12F, CC12-CHC12,

CH2CH2F, CI3, etc. Throughout this description, halogen shall

is understood to mean fluorine, chlorine, bromine or iodine, with fluorine, chlorine or bromine being preferred. C3-C8-alkenyl is an unsaturated, alipha-

tical group containing one or more double-bond indi-

gives, e.g. 1-propenyl, allyl, 1-butenyl, 2-butenyl, 3-

butenyl, CH3CH=CHCH=CH- etc. Alkynyl shall be understood to mean unsaturated aliphatic groups containing a maximum of 6 carbon atoms, e.g. propargyl, 2-butynyl, 3-butynyl, etc.

Under normal conditions, the compounds of formula I

stable oils, resins or essentially crystalline

linseed solids that are distinguished by very valuable microbial properties. They can be used, for example, in agriculture or in related areas preventively or combatively to control phytopathological microorganisms. The compounds of formula I are distinguished by very good fungicidal activity in a wide range of concentrations and their use entails no problems.

The compounds of formula I which are preferred because of their pronounced microbial properties are those which contain as X the following substituents or combinations of these substituents: hydrogen or CO-R^, wherein R^ is C1-C6 alkyl which is unsubstituted or substituted with halogen or C 1 -C 3 alkoxy; or C 3 -C 6 -alkenyl, C 3 -C 6 -alkynyl or C 3 -C 6 -alkyloxy; or is C3-C6-alkenyloxy, C3-C8-cycloalkyl or tetrahydrofuran-2-yl.

Among the compounds of formula I which have combinations of substituents defined in the group above, the compounds in which X has the following meanings are particularly preferred: hydrogen or CO-R^, in which R^ is C1-C4-alkyl which is unsubstituted or substituted by chlorine . or is C3-C4-alkenyloxy, C3-C6-cycloalkyl or tetrahydrofur-2-yl.

Among the compounds of formula I, the following individual substances are preferred, particularly because of their excellent fungicidal properties: 3-(2,2-difluorobenzodioxol-4-yl)-4-cyanopyrrole (compound 1.1), l-acetyl-3-( 2,2-difluorobenzodioxol-4-yl)-4-cyanopyrrole (compound 1.2),

1-methoxyacetyl-3-(2,2-difluorobenzodioxol-4-yl)-4-cyanopyrrole (compound 1,15),

1-methoxycarbonyl-3-(2,2-difluorobenzodioxol-4-yl)-4-

cyanopyrrole (compound 1.24), 1-allyloxycarbonyl-3-(2,2-difluorobenzodioxol-4-yl)-4-cyanopyrrole (compound 1.30), 1-n-propoxyacetyl-3-(2,2-difluorobenzodioxol-4-yl )-4-cyanopyrrole (compound 1.32).

In addition, the first-mentioned compound is particularly important as an intermediate in the synthesis of other fungicidal substances.

The compounds of formula I are prepared

a) in alkaline medium by carrying out a Michael cycloaddition reaction 2,3-(difluoromethylenedioxyl)cinnamonitrile with

formula II with p-toluenesulfonylmethyl isocyanide, with elimination of p-toluenesulfonic acid or a salt thereof, in an organic solvent:

Me is an alkali metal ion or an alkaline earth metal ion, and

b) by then acylating the compound of formula Ia with a compound of formula III, in the presence of an acid acceptor and

optionally a catalyst, in an organic solvent:

R± is as defined above for formula I, or

c) by sulfenylizing the compound of formula Ia with a reactive acid derivative of a sulfenic acid of formula IV

on the nitrogen atom of the pyrrole, in the presence of an acid acceptor, optionally in an organic solvent, R2 is O^-O3, or d) by reacting the compound of formula Ia with an aldehyde of formula V where R3 is hydrogen or C^^-Cg -haloalkyl, to form a hydroxy derivative of formula Ic and to convert said hydroxy derivative into another product of formula I by replacing the OH group with another residue Y, which replacement is carried out by converting a compound of formula Ic either with an acid with formula VI where R 4 is C 1 -C 8 -alkyl, C 1 -C 8 -haloalkyl, C 2 -C 6 -alkenyl, tetrahydrofur-2-yl, tetrahydropyran-2-yl or C 1 -C 8 -alkoxycarbonyl, or preferably with a reactive acid derivative thereof, most preferably with an acid halide, e.g., an acid chloride or acid bromide, or with the acid hydride thereof, to an acyloxy product of formula Id where R3 and R4 are as defined above, or by first replacing the OH group in a compound of formula Ic with a halogen atom, preferably a chlorine or bromine atom on it conventional way to form a compound of formula Ie wherein R 3 is as defined above, and Hal is halogen, and then again to convert said halogenated product by reaction with a salt of formula VII wherein R 4 is as defined above, and M+ is a metal cation , preferably an alkaline earth metal cation, e.g. Mg<++>, Na<+ >or IC*" to a compound of formula Id, or e) either by reacting the compound of formula Ia with a compound of formula VIII where Z is one of the groups

wherein each of R 5 and R 6 is independently hydrogen, C 1 -C 8 alkyl which is unsubstituted or substituted by cyano or C 1 -C 8 alkoxycarbonyl; or is C3-C6-alkenyl, C3-C6-alkynyl, C3-C7-cycloalkyl, or phenyl which is unsubstituted or substituted by halogen, C1-C8-alkyl, C1-C8-halogenoalkyl or C1-C8-alkoxy, with the proviso that only R 5 or R 8 can be hydrogen; each of R 7 and R 8 independently of the other is hydrogen, C 1 -C 8 alkyl or C 1 -C 8 alkoxycarbonyl, or both together form a fused aromatic ring; each of R 9 and R 10 independently of the other is hydrogen, C 1 -C 8 alkyl or C 1 -C 8 alkoxycarbonyl; and X is oxygen, sulphur, y<Z=Q or J^N-Ru, where R^ is hydrogen, C 1 -C 8 alkyl, formyl, C 1 -C 8 alkanoyl or C 1 -C 8 alkoxycarbonyl; and n is 0 or 1;

and formaldehyde, in a protic solvent, in the temperature range from 0°C to 120°C, preferably from 20°C to the reflux temperature, and in the presence of a basic catalyst; or by reacting the compound of formula Ia with a compound of formula VIII and 1,3,5-trioxane or paraformaldehyde, in an aprotic solvent, in the presence of a basic catalyst, and in temperature ranges from 0°C to 120°C, preferably from 20°C to 80°C.

Reaction step (a):

Here, the p-tolylsulfonyl group represents a large number of groups that can activate the methylene group of the methyl isocyanide radical for a Michel addition reaction. Other preferred examples of such activating groups are benzenesulfonyl, p-chlorobenzenesulfonyl, lower alkylsulfonyl, such as mesyl.

The cycloaddition is preferably carried out in the presence of a non-nucleophilic base. Suitable bases are alkali metal hydrides, such as sodium hydride, or alkali metal carbonates or alkaline earth metal carbonates such as Na2CC>3, K2CO3, or alkali metal alcoholates such as (CH^^CO-!^ and others. The base is advantageously used in at least an equimolar amount, based on the starting materials.

It is convenient to carry out the cycloaddition reaction in an inert solvent. Examples of preferred anhydrous solvents suitable for cycloaddition are: aromatic and aliphatic hydrocarbons, such as benzene, toluene, xylenes, petroleum ethers, ligroin, cyclohexane ethers and ether compounds such as dialkyl ethers (diethyl ether, diisopropyl ether, tert-butyl methyl ether etc), dimethoxymethane, tetrahydrofuran, anisole ; sulfones such as dimethyl sulfoxide; dimethylformamide and mixture of such solvents. The cycloaddition is usually carried out in the temperature range from -30°C to +120°C, preferably from -30°C to +50°C, or at the boiling point of the solvent or solvent mixture.

When a suitable base is to be chosen, the cycloaddition can also conveniently be carried out in an aqueous medium. Suitable bases in such cases are water-soluble inorganic and organic bases, especially alkali metal hydroxides such as LiOH, NaOH or KOH, and ammonium bases, e.g. tetraalkylammonium hydroxides such as (CH 3 ) 4 NOH. At least an equimolar amount of the base is used, based on the starting materials. When an aqueous base is used, it is advantageous to carry out the reaction in a heterogeneous tb phase system.

Examples of suitable solvents for the organic base which are not miscible with water are: aliphatic and aromatic hydrocarbons, such as pentane, hexane, cyclohexane, petroleum ether, naphtha, benzene, toluene, xylenes etc.; halogenated hydrocarbons such as dichloromethane, chloroform, carbon tetrachloride, ethylene dichloride, 1,2-dichloroethane, tetrachloroethylene, etc.; or aliphatic ethers such as diethyl ether, diisopropyl ether, tert-butyl methyl ether, etc.

The presence of a phase transfer catalyst can be beneficial when the reaction is carried out in this way to increase the reaction rate. Examples of such catalysts are: tetraalkylammonium halides, hydrogen sulphates or hydroxides such as tetrabutylammonium chloride, bromide or iodide; triethylbenzylammonium chloride or bromide; tetrapropylammonium chloride, bromide or iodide etc. Phosphonium salts are also suitable for use as phase transfer catalysts.

The phase transfer-catalyzed cycloaddition can be carried out in the temperature range from 0°C to 80°C, preferably from 10°C to 50°C or at the boiling point of the solvent mixture. The cycloaddition can be carried out in the described embodiment of the process at normal pressure. The reaction time is generally from 1 to 16 hours, and with phase transfer catalysis from 1/2 hour to 10 hours.

Reaction step (b):

The acylation of the compound of formula Ia is carried out under normal conditions well known in the art.

Examples of suitable inert solvents or diluents are: aliphatic and aromatic hydrocarbons, such as benzene, toluene, xylenes, petroleum ether; halogenated hydrocarbons such as chlorobenzene, methylene chloride, ethylene chloride, chloroform, carbon tetrachloride, tetrachloroethylene; ethers and ether compounds, such as dialkyl ethers (diethyl ether, diidopropyl ether, tert-butyl methyl ether, etc.), dioxane, tetrahydrofuran; nitriles such as acetonitrile, propionitrile; ketones such as acetone, diethyl ketone, methyl ethyl ketone; and mixtures of such solvents. Dimethylformamide, tetrahydrofuran and dioxane are preferred.

Examples of suitable acid acceptors are inorganic bases, e.g. oxides, hydroxides, carbonates or bicarbonates of alkali metals or alkaline earth metals, as well as alkali metal hydrides or alkali metal acetates, and also organic bases, e.g. tertiary amines such as trialkylamines, (trimethylamine, triethylamine etc), pyridine or pyridine bases (4-dimethylaminopyridine, 4-pyrrolidylaminopyridine). Preferred acid acceptors are trialkylamines such as trimethylamine or triethylamine.

The reaction temperature varies depending on the reaction conditions. It is usually in the range from -25° to +100°C, preferably from -10° to +75c.

Reaction step (c).

Suitable reactive sulfenic acid derivatives for this sulfenylation reaction are e.g. the lower alkyl esters and preferably the sulfenic acid halides, especially the chlorides and bromides, with the chlorides being particularly preferred. Lower alkyl is to be understood here to mean Ci-Cg-alkyl.

Both organic and inorganic bases can be successfully used in the above-mentioned reaction. Examples of suitable inorganic bases are alkali metal carbonates and alkaline earth metal carbonates such as sodium carbonate, potassium carbonate, calcium carbonate etc. Examples of suitable organic bases are tertiary amines such as trialkylamines (triethylamine, methyldiethylamine), N,N-dimethoxycyclohexylamine, N-methylpiperidine, N, N-dimethylaniline or pyridines. The trialkylamines are preferred. It is advantageous to use the base in a stoichiometric amount or in an excess thereof, e.g. up to 100% excess of the stoichiometric amount based on the pyrrole of formula Ia. The reactive derivative of the sulfenic acid with formula IV is also used in a stoichiometric amount or in excess thereof.

The sulfenylation reaction can be carried out in the presence or absence, preferably in the presence of an inert solvent or mixture of solvents. In principle, the usual organic solvents are suitable for this reaction, provided that they do not contain reactive hydrogen atoms. Examples of suitable solvents are: aliphatic and aromatic hydrocarbons such as benzene, toluene, xylenes, petroleum ethers; halogenated hydrocarbons such as chlorobenzene, methylene chloride, ethylene chloride, chloroform, carbon tetrachloride, tetrachloroethylene; ethers and ethereal compounds such as dialkyl ethers (diethyl ether, diisopropyl ether, tert-butyl methyl ether etc), ethylene glycol di- and monoether and diethylene glycol di- and monoether, which contain 1 to 4 carbon atoms in each of the alkyl groups, e.g. ethylene glycol dimethyl, diethyl and di-n-butyl ether, diethylene glycol diethyl and di-n-butyl ether, ethylene glycol monoethyl ether and diethylene glycol monomethyl ether; furan, dimethoxyethane, dioxane, tetrahydrofuran, anisole; sulfones such as dimethyl sulfoxide; ketones such as acetone, methyl ethyl ketone; esters such as ethyl acetate, propyl acetate, butyl acetate; and mixtures of such solvents. In some cases, the sulfenylation reagent of formula IV can itself be used as a solvent.

To increase the reaction rate, a catalyst such as 4-dimethylaminopyridine can be added, if appropriate.

The sulfenylation reaction is usually carried out in the temperature range from -30° to +100°C, preferably from -10° to +20°C. The reaction time is usually from 1/2 hour to 20 hours. However, the addition of a reaction catalyst can reduce the reaction time to less than 1/2 hour.

Reaction step (&).

The reaction of the compound of formula Ia with aldehydes of formula V can be carried out in the presence or absence of an inert solvent or mixture of solvents. Examples of suitable solvents are: aromatic hydrocarbons such as benzene, toluene or xylenes; halogenated hydrocarbons such as chlorobenzene; aliphatic hydrocarbons such as petroleum ether; ether and ethereal compounds such as dialkyl ethers (diethyl ether, diisopropyl ether, tert-butyl methyl ether etc), furan, dimethoxyethane, dioxane, tetrahydrofuran; and dimethylformamide, etc..

The reaction compounds of formula Ia with compounds of formula V are conveniently carried out without a solvent, but using an excess of the aldehyde of formula V. Depending on the nature of the aldehyde, the reaction is carried out in solution or in the melt. The reaction rate can be increased by adding an acidic or basic catalyst. Examples of suitable acid catalysts are non-aqueous hydrogen halides and mineral acids such as HCl, HBr or H2SO4, and also concentrated hydrochloric acid. Examples of suitable basic catalysts that can be used are: trialkylamines (trimethylamine, triethylamine, dimethylethylamine etc), alkali metal carbonates and alkaline earth metal carbonates (such as Na2C03, BaC03. MgC03, K2C03 etc), or alkali metal alcoholates (such as NaOCH3, NaOC2H5, KO(iso-C3H7 ), KO(tert-butyl)). The reaction temperatures are normally in the range from 0° to 200°C, preferably from 0<0> to 160°C, and the reaction time is from 1 to 24 hours, preferably from 1 to 4 hours.

The reaction to replace the free hydroxyl group in the compounds of formula Ic with a group Y is preferably carried out in an inert solvent. Examples of such solvents are: aromatic and aliphatic hydrocarbons such as benzene, toluene, xylenes, petroleum ether, ligroin or cyclohexane, halogenated hydrocarbons such as chlorobenzene, methylene chloride, ethylene chloride, chloroform, carbon tetrachloride or tetrachloroethylene; ethers and ethereal compounds such as diethyl ether, diisopropyl ether, tert-butyl methyl ether, dimethoxyethane, dioxane, tetrahydrofuran or anisole; esters such as ethyl acetate, propyl acetate or butyl acetate; nitriles such as acetonitrile, or compounds such as dimethylsulfoxide, dimethylformamide and mixtures of such solvents.

The importation of group Y is carried out in conventional ways. If Y is chlorine, the reagent used is e.g. phosphorus oxychloride, phosphorus trichloride, phosphorus pentachloride or preferably thionyl chloride. The reaction is usually carried out in the temperature range from 0° to 120°C. If Y is bromine, the preferred reagent is phosphorus tribromide or phosphorus pentabromide and the reaction is carried out in the temperature range 0° to 50°C. If Y is - the 0-C(0)-R4 group, the corresponding acid halide, preferably acid chloride, will usually be used as reagent. In this case, it is appropriate to carry out the reaction in the temperature range from -20° to +50°C, preferably -10° to +30°C, and in the presence of a weak base such as pyridine or triethylamine. To increase the reaction rate, it is also possible to add a 4-dialkylaminopyridine such as 4-dimethyl- or 4-diethylaminopyridine as a catalyst.

The reaction of compounds of formula I with salts of formula VII is usually carried out in the presence of a commonly used inert solvent or mixture of solvents. Examples of such solvents are: aromatic and aliphatic hydrocarbons such as benzene, toluene, xylenes, petroleum ether, ligroin or cyclohexane, ethers and ethereal compounds such as dialkyl ethers, e.g. diethyl ether, diisopropyl ether, tert-butyl methyl ether, dimethoxyethane, dioxane, tetrahydrofuran or anisole; esters such as ethyl acetate, propyl acetate or butyl acetate; nitriles such as acetonitrile; or compounds such as dimethylsulfoxide, dimethylformamide and mixtures of such solvents.

The course of this reaction can be advantageously influenced by the addition of catalytic amounts of a crown ether; e.g. 18-krona-6 or 15-krona-5. The reaction temperature is usually in the range from 0° to 150°C, preferably from 20° to 80°C. The reaction time is from 1 to 24 hours.

In a preferred embodiment, the preparation of compounds of formula Id, especially those in which R 3 is CC 13 or R 3 is H, is achieved starting from compounds of formula la, by carrying out the reaction continuously without isolating the intermediates that are formed. This reaction is conveniently carried out in one of the solvents or diluents mentioned above, most conveniently in e.g. an ethereal compound such as tetrahydrofuran, and in the presence of a weak base such as a trialkylamine (triethylamine) or pyridine. Chloral or paraformaldehyde is used as a reagent. The reaction can be increased by adding a catalyst such as 1,8-diazabicyclo[5.40]undex-7-ene [DBU]. The temperature in this first reaction step is in the range from -20° to +100°C, preferably from 0° to +50°C, and the reaction time is from 1/2 hour to 2 hours. A hydroxy derivative of formula Ic is obtained as an intermediate product. This intermediate product is not isolated, but is reacted with a compound of formula VI in the same reaction solution, in the temperature range from -30° to +30°C, preferably from -10° to 0°C, and in the presence of catalytic amounts of a 4 -dialkylaminopyridine, preferably 4-dimethylaminopyridine. The reaction time for this second step is from 1/2 to 16 hours.

The starting materials of formulas V, VI and VII are generally known or they can be prepared by methods which are known per se.

Reaction step ( e ).

The reaction of the compound of formula Ia with a compound of formula VIII is preferably carried out in a suitable inert solvent. Examples of suitable protic solvents OOOs: Water, alcohols (preferably alkanols such as methanol, ethanol, isopropanol, n-propanol etc), or carboxylic acids (preferably alkanecarboxylic acids such as formic acid, acetic acid, propionic acid etc.)" If the process is carried out in a protic solvent then can e.g. the following reaction catalysts are used: organic bases such as 1,8-diazabicyclo[5.4.0]undec-7-ene, tertiary amines such as trialkylamines (trimethylamine, triethylamine, dimethylethylamine etc), triethylenediamine, piperidine, pyridine, 4-dimethylaminopyridine, 4 -pyrrolidylpyridine etc, or inorganic bases such as the oxides, hydroxides, hydrides, carbonates, bicarbonates and alcoholates of alkali metals or alkaline earth metals (e.g. Na2C03, BaC03, MgC03, K2C03, NaHC03, KHC03, Ca(HC03)2, NaOCH3, NaOC2H5 , KO(iso-C3H7), KO(tert-butyl), NaH, CaO Etc); organic acids such as carboxylic acids (acetic acid, formic acid, propionic acid, etc.), aliphatic and aromatic sulfonic acids such as methanesulfonic acid, ethanesulfonic acid, toluenesulfonic acid, benzenesulfonic acid, etc.; inorganic acids such as mineral acids, e.g. phosphoric acid, sulfuric acid, nitric acid or hydrohalic acid (hydrochloric acid, hydrobromic acid, hydroiodic acid or hydrofluoric acid). It is appropriate to use catalytic amounts of acids or bases in this variant. In general, an excess of amine of formula VIII will be sufficient. In this variant, the formaldehyde is preferably used in the form of its aqueous solution (formalin) or as a trimer (1,3,5-trioxane) or polymer (paraformaldehyde).

Suitable aprotic solvents are e.g. aliphatic or aromatic hydrocarbons such as benzene, toluene, xylenes, petroleum ether, naphtha or cyclohexane; ethers and ethereal compounds such as diethyl ether, diisopropyl ether, tert-butyl methyl ether, dimethoxyethane, tetrahydrofuran, dioxane or anisole; esters such as ethyl acetate, propyl acetate or butyl acetate, or compounds such as dimethylformamide, dimethylsulfoxide or mixtures of such solvents. In this reaction step, it is preferred to use formaldehyde.

The sulfenic acids of formula IV and the amines of formula VIII are known or they can be prepared according to methods known per se.

The cinnamonitrile of formula II as starting material for the compound of formula Ia is prepared from 2,3-(difluoromethylenedioxy)aniline of formula IX which is converted to the diazonium salt of formula XX in a conventional manner that is well known in the art: The diazonium salt of formula X is then allowed to react with the acrylonitrile with formula XI in the presence of Cu(I) chloride in an aqueous reaction medium containing a dialkyl ketone as solvent, to form the adduct of formula XII

The HC1 is then eliminated by reacting the compound of formula XII with an acid acceptor in an inert organic solvent to form 2,3-(difluoromethylenedioxyl)cinnamonitrile of formula II, which product is a mixture of the cis and trans isomers which can be separated by krornatography in the usual way:

The reaction of the diazonium salt of formula X with acrylonitrile of formula XI is a modification of the normal Sandmeyer method under the conditions of the Meerwein reaction of aromatic diazonium compounds with cx-,P-unsaturated carbonyl compounds, whereby the substitution of the diazonium group by halogen is withheld to advantage for the addition reaction (q.v. E. Maller, Angewandte Chemie 61, pp. 178-183, 1949).

In the practical implementation of the reaction, the reactants (diazonium salt and acrylonitrile) are used in a ratio in the range 1:1 to 1:8, preferably in a range from 1:2. The reaction temperature is in the range of 20° to 50°C, preferably from 25° to 35°C. The reaction time is from 1/2 hour to 10 hours, preferably from 1 to 3 hours. It is preferred to use ethyl methyl ketone which dissolves in the aqueous reaction medium.

Inert solvents for the reaction to eliminate HCl from the compound of formula XII are e.g. aliphatic and aromatic hydrocarbons such as benzene, toluene, xylenes, petroleum ether; halogenated hydrocarbons such as chlorobenzene, methylene chloride, ethylene chloride, chloroform, carbon tetrachloride, tetrachloroethylene; ether and ethereal compounds such as dialkyl ethers (diethyl ether, diisopropyl ether, tert-butyl methyl ether etc), dioxane, tetrahydrofuran; nitriles such as acetonitrile, propionitrile, N,N-dialkylated amides such as dimethylformamide; dimethyl sulfoxide; ketones such as acetone, diethyl ketone, methyl ethyl ketone and mixtures of such solvents. Suitable acid acceptors are weakly nucleophilic organic bases, preferably trialkylamines. The elimination reaction is carried out in the temperature range from room temperature to the reflux temperature of the solvent used, preferably in the range from 30° to 60°C. The reaction time is from 1 to 24 hours, preferably from 3 to 12 hours.

The compound of formula II is a valuable intermediate in the production of fungicides and, as a new compound, it forms part of the present invention.

Some 3-phenyl-4-cyanopyrrole derivatives are known as fungicides. Such compounds are described e.g. in Tetrahedron Letters 52, pp. 5537-5340 (1972) and in German Offenlegungs-schrift 29 27480. However, the effectiveness of the known derivatives has not always been proven to a completely satisfactory degree.

Surprisingly, it has now been found that the compounds of formula I according to this invention have a very advantageous spectrum of pesticidal activity against harmful microorganisms, in particular against phytopathogenic fungi and bacteria for practical use. The compounds of formula I have very advantageous curative, systemic and especially preventive properties and can be used to protect a number of cultivated plants. With the compounds of formula I it is possible to inhibit or destroy the pests that appear in plants or in parts of plants (fruits, flowers, leaves, stems, root-tubers, roots) in various crops of useful plants, while at the same time the parts of the plants that grow later are also protected against attack by phytopathogenic microorganisms.

The compounds of formula I are effective against e.g. phytopathogenic fungi belonging to the following classes: Ascomylcetes, e.g. Erysiphe, Schlerotinia, Fusarium, Monilinia, Helminthosporium; Basidiomycetes, e.g. Puccinia, Tilletia, Rhizoctonia; as well as Oomycetes belonging to the class of Phycomyces, e.g. Phytophthora. As plant protection agents, the compounds of formula I can be used with particular success against important harmful fungi of the Fungi imperfecti family, e.g. against Cercospora, Pyricularia and especially against Botrytis, Botrytis spp. (B. cinerea, B. allii) and gray mold on wine, strawberries, apples, onions and other varieties of fruit and vegetables which are a source of considerable economic damage . Compound 1.1 in table 1 in particular has a broad spectrum of activity. It exhibits excellent fungicidal activity not only against Pyhricularia, Botrytis and Rhizoctonia, but is also suitable for fortunately controlling Erysiphe and Venturia species. Furthermore, the compounds of formula I have a systemic effect. In addition, the compounds of formula I can be successfully used to protect perishable goods of vegetable or animal origin. They control molds such as Penicillium, Aspergillus, Rhlizopus, Fusarium, Helminthosporium, Nigrospora and Alternaria, as well as bacteria such as butyric acid bacteria and yeasts such as Candida. Furthermore, these compounds have excellent activity against fungi that occur in seeds or the soil.

As plant protection agents, the compounds of formula I have a very advantageous spectrum of activity for practical use in agriculture to protect cultivated plants without damaging said plants by harmful side effects.

The compounds of formula I can also be used as "dressing" agents to protect seeds (fruit, tubers, grains) and plant cuttings against fungal infections and against phytopathogenic fungi that occur in the soil. The compounds of formula I are particularly very effective grain dressings for controlling fungal organisms such as Fusarium, Helminthosporium and Tilletia species.

According to this, the invention also relates to microbicidal mixtures and the use of the compounds of formula I to control phytopathogenic microorganisms, in particular phytopathogenic fungi, and for the preventive treatment of plants and stored goods of vegetable or animal origin to protect them against attack by such microorganisms. Crops to be protected according to the present invention include e.g. the following types of plants: cereals (wheat, barley, rye, oats, rice, sorghum and related crops), beets (sugar beets and beets), stone fruits, stone fruits and berries (apples, pears, plums, peaches, almonds, cherries, strawberries, raspberries and blackberries), legumes (beans, lentils, peas, soybeans), oil plants (rapeseed, mustard, poppy, olive, sunflower, coconut, common oil plants, cocoa beans, peanuts), cucurbits (cucumber, pumpkin, melons) fiber plants (cotton , flax, hemp, jute), citrus fruits (oranges, lemons, grapefruit, tangerines), vegetables (spinach, lettuce, asparagus, cabbage, carrots, onions, tomatoes, potatoes, peppers), the laurel family (avocados, cinnamon, camphor) or plants such as maize, tobacco, nuts, coffee, sugar cane, tea, wine, hops, bananas and natural rubber plants, as well as ornamental plants (composites).

For storage protection, the compounds of formula I are used in unmodified form or preferably together with additives which are usually used in formulation and are therefore formulated in a known manner for e.g. emulsifiable concentrates, brushable pastes, directly sprayable or dilutable solutions, diluted emulsions, wettable powders, soluble powders, dust, granules and also encapsulations in e.g. polymeric substances. The application methods such as spraying, atomizing, atomizing, spreading, coating or pouring and the formulation of the mixture are chosen according to the intended goals and the present conditions. Suitable application rates are generally in the range from 0.01 to no more than 2 kg of the active ingredient per 100 kg of the substrate to be protected. However, they depend to a very large extent on the nature (surface area, consistency, moisture content of the substrate and the influences from its surroundings.

Within the scope of this invention, stored goods will implicitly mean natural substances of vegetable and/or animal origin and the products obtained therefrom by further processing, e.g. the plants listed above whose natural life cycle has been interrupted and parts thereof (stems, leaves, feet, seeds, fruit, grains) that are freshly harvested or present in further processed form (dried, moistened, ground, crushed, shaken). The following agricultural products can be mentioned as examples without limiting the field of application within the invention: cereals (wheat, barley, rye, wheat, rice, sorghum and related crops); beetroot (carrots, sugar beetroot and beetroot), apple fruit, stone fruit and soft fruit (apples, pears, plums, peaches, almonds, cherries, strawberries, raspberries and blackberries); legumes (beans, lentils, peas, soybeans); oil plants (rapeseed, mustard, poppy, olive, sunflower, coconuts, castor oil plants, cocoa beans, peanuts); cucumber plants (cucumber, pumpkin, melons); fiber plants (cotton, flax, hemp, jute, ramie); citrus fruits; vegetables (spinach, lettuce, asparagus, cabbage, onions, tomatoes, potatoes, peppers); the laurel family (avocados, cinnamon, camphor) corn, tobacco, nuts, coffee, sugar cane, tea, wine, chestnuts, hops, bananas, grass and hay.

Examples of natural products of animal origin of specially dried meat and further processed fish products, such as dry-salted fish, meat extracts, bone meal and fish meal and dry feed for animals.

Stored goods treated with compounds of formula I are given lasting protection against attack by molds and other undesirable microorganisms. The formation of toxic and in some cases carciogenic molds (aflatoxins and ochratoxins) is inhibited, and the goods are preserved from degradation, and their quality is maintained for an extended period of time. The method according to the invention can be used on all forms of dry and moist stored goods which are susceptible to attack by microorganisms such as yeasts, bacteria and especially molds.

A preferred method for applying the active agent comprises spraying or wetting the substrate with a liquid formulation, or mixing the substrate with a solid formulation of the active agent. The invention also relates to the described method for preserving stored goods.

The compounds of formula I are usually applied in the form of mixtures and can be applied to the crop area, the plant or the substrate to be treated, simultaneously or in sequence, with other compounds. These compounds can both be fertilizers or micronutrients or other preparations that affect plant growth. They can also be selective herbicides, insecticides, fungicides, bactericides, nematicides, molluscicides or a mixture of several of these compositions, if desired together with additional carriers, surface-active agents or application-promoting additives usually used in the art.

Suitable carriers and additives can be solid or liquid and correspond to the substances usually used in the formulation technology, e.g. natural or regenerated mineral substances, solvents, dispersants, wetting agents, fixing agents, thickeners, binders or fertilisers. Phospholipids are particularly advantageous additives.

A preferred method for applying a compound of formula I, or an (agro)chemical mixture containing at least one of said compounds, is foliar application. The number of applications and the speed of application depend on the risk of attack by the corresponding pathogens (species of fungi). However, the compound of formula I can also penetrate the plant through the roots via the soil (systemic effect) by impregnating the plant's growth site with a liquid formulation or by applying the compounds in solid form to the soil, e.g. in granular form (soil application). The compounds of formula I can also be applied to seeds

(coating) by impregnating the seeds either with a liquid formulation containing a compound of formula I or

coating them with a fixed formulation. In special cases, further application types are also possible, e.g. selective treatment of the plant stems and buds.

The compounds of formula I are used in unmodified form or, preferably together with additives that are usually used in the art, and are therefore formulated in a known manner into emulsifiable concentrates, coatable pastes, directly sprayable or dilutable solutions, diluted emulsions, wettable powders, soluble powders, dust, granules and also encapsulations in e.g. polymeric substances. As with the nature of the mixtures, the methods of application, such as spraying, atomizing, atomizing, spreading, coating or pouring, are chosen according to the intended objects and the present conditions. Beneficial application rates are usually from 50 g to 5 kg of active ingredient (a.i.) per hectare, preferably from 100 g to 2 kg a.i./ha, most preferably from 200 g to 600 g a.i./ha..

The formulations, i.e. the mixtures, preparations or compositions containing the compound (active ingredient) of formula I and where appropriate a solid or liquid additive is prepared in a known manner, i.e. by homogeneously mixing and/or grinding the active agents with additives, e.g. solvents, solid carriers and, when necessary, surfactants.

Suitable solvents are: aromatic hydrocarbons, preferably fractions containing 8 to 12 carbon atoms, e.g. xylene mixtures or substituted naphthalenes, phthalates such as dibutyl phthalate or dioctyl phthalate, aliphatic hydrocarbons such as cyclohexane or paraffins, alcohols and glycols and their ethers and esters, such as ethanol, ethylene glycol, ethylene glycol monomethyl or monoethyl ether, ketones such as cyclohexanone, strongly polar solvents such as N-methyl-2-pyrrolidone, dimethylsulfoxide or dimethylformamide, as well as vegetable oils or epoxidized vegetable oils such as epoxidized coconut oil, sunflower oil or soybean oil; or water. The solid carriers used for dusts and dispersible powders are usually natural mineral fillers such as calcite, talc, kaolin, montmorillonite or attapulgite. To improve the physical properties, it is also possible to add highly dispersed silicic acid or highly dispersed absorbent polymers. Suitable granular adsorbent carriers are porous types, e.g. pumice, crushed brick, sepiolite or bentonite, and suitable non-absorbent carriers are materials such as calcite or sand. In addition, a large number of pre-granulated materials of an inorganic and organic nature can be used, e.g. especially dolomite or powdered plant residues, e.g. cork powder or sawdust.

Depending on the nature of the compound of formula I to be formulated, suitable surfactants are non-ionic, cationic and/or anionic surfactants having good emulsifying, dispersing and wetting properties. The term "surfactants" shall also be understood as including mixtures of surface-active agents.

Suitable anionic surfactants can be both water-soluble soaps and water-soluble synthetic surfactant compounds.

Suitable soaps are alkali metal salts, alkaline earth metal salts or unsubstituted or substituted ammonium salts of higher fatty acids (C20-C22), e.g. the sodium or potassium salts of oleic or stearic acid or of natural fatty acid mixtures which can be obtained, e.g. from coconut oil or tallow oil. Fatty acid methyl taurine salts may also be mentioned.

However, so-called synthetic surface-active agents are used more frequently, in particular fatty sulphonates, fatty sulphates, sulphonated benzimidazole derivatives or alkyl sulphonates.

The fat sulfonates or sulfates are usually in the form of alkali metal salts, alkaline earth metal salts or unsubstituted or substituted ammonium salts and contain a C8-C22 alkyl residue and also include the alkyl residue of the acyl groups, e.g. the sodium or calcium salt of lignosulfonic acid, of dodecyl sulfate or of a mixture of fatty alcohol sulfates obtained from natural fatty acids. These compounds also include the salts of sulfuric acid esters and sulphonic acids of fatty alcohol/ethylene oxide adducts. The sulfonated benzimidazole derivatives preferably contain 2 sulfonic acid groups and a fatty acid group containing 8 to 22 carbon atoms. Examples of alkylarylsulfonates are sodium, calcium or triethanolamine salts of dodecylbenzenesulfonic acid, dibutylnaphthalenesulfonic acid or of a naphthalenesulfonic acid/formaldehyde condensation product. Also appropriate are corresponding phosphates, e.g. salts of the phosphoric acid ester of an adduct of p-nonylphenol with 4 to 14 ethylene oxide.

Non-ionic surfactants are preferably polyglycol ether derivatives of aliphatic or cycloaliphatic alcohols, or saturated or unsaturated fatty acids and alkylphenols, and said derivatives contain 3 to 30 glycol ether groups and 8 to 20 carbon atoms in the (aliphatic) hydrocarbon group and 6 to 18 carbon atoms in alkyl -group of the alkylphenols.

Other suitable non-ionic surfactants are water-soluble adducts of polyethylene oxide with polypropylene glycol, ethylene diaminopropylene glycol and alkyl polypropylene glycol containing 1 to 10 carbon atoms in the alkyl chain, which adducts contain 20 to 250 ethylene glycol ether groups and 10 to 100 propylene glycol ether groups. These compounds usually contain 1 to 5 ethylene glycol units per propylene glycol unit.

Representative examples of nonionic surfactants are nonylphenyl polyethoxyethanols, castor oil polyglycol ethers, polypropylene/polyethylene oxide adducts, tributylphenoxypolyethyleneethanol, polyethyleneglycol and octylphenoxypolyethoxyethanol. Fatty acid esters of polyoxyethylene sorbitan, e.g. polyoxyethylene sorbitan trioleate, are also suitable non-ionic surfactants.

Cationic surfactants are preferably quaternary ammonium salts containing, as N-substituent, at least one C8-C22 alkyl group, and as other substituents, unsubstituted or halogenated alkyl, benzyl or hydroxy-lower alkyl groups. The salts are preferably in the form of halides, methyl sulphates or ethyl sulphates, e.g. stearyltrimethylammonium chloride or benzyldi(2-chloroethyl)ethylammonium bromide. In the area of storage protection, the excipients which are acceptable in the nutrient for animals and humans are preferred.

The agrochemical mixtures usually contain 0.1 to 99% by weight, preferably 0.1 to 95% by weight, of a compound of formula I, 99.9 to 1% by weight, preferably 99.8 to 5% by weight, of a solid or liquid additive, and 0 and 25% by weight, preferably 0.1 to 25% by weight of a surfactant.

While commercial products will preferably be formulated as concentrates, the user will usually use diluted formulations. The mixtures may also contain other auxiliary substances, such as stabilizers, anti-foaming substances, viscosity-regulating substances, binders, adhesion agents as well as fertilizers or other active agents to achieve special effects.

Such (agro)chemical mixtures form part of the present invention.

The invention is illustrated by the following examples (percent and parts are by weight).

Production examples

1. 1 Preparation of 2. 3-(difluoromethylenedioxy) cinnamonitrile

a) 50 ml of 32% hydrochloric acid and 6 ml of water are added to a solution of 34.6 g of 4-amino-2,2-difluorobenzodioxole in 71 ml

acetic acid. A solution of 15 g of sodium nitrite in 30 ml of water is added dropwise at 0°C to the resulting mixture. The batch is then stirred for 1 hour at 0°C. The resulting suspension is then fed in portions at 27-30°C into 27 ml of acrylonitrile and 24 ml of ethyl methyl ketone. At the same time, a solution of 0.75 g of Cu(I) chloride in 7.5 ml of 32% hydrochloric acid is added dropwise from a separate dropping funnel. When the dropwise addition is complete, the mixture is stirred for a further 30 minutes at 35°C and then poured onto ice. The mixture is extracted twice with methylene chloride, the organic phases are extracted twice with dilute ice-cold sodium hydroxide solution, dried over sodium sulfate and filtered, and the filtrate is concentrated to a volume of 700 ml.

b) 34.6 ml of triethylamine is added to the aforementioned methylene chloride solution, and the batch is heated under reflux for 12 hours. After cooling, the dark solution is poured into ice water. The phases are separated and the aqueous phase is extracted again with methylene chloride. The organic phases are extracted twice with ice-cold dilute hydrochloric acid and

then they are washed with a half-saturated solution of sodium chloride, dried over sodium sulfate and filtered, and the filtrate is concentrated. By chromatography of the crude mixture of cis and trans isomers (eluent: a 20:1 mixture of petroleum distillate and ethyl acetate), the trans isomer (the main isomer in the mixture) of the aforementioned cinnamonitrile can be obtained in pure form. Yellowish crystals with a melting

point at 53-560C.

NMR (60 MHz, CFCl 3 ) 6.2 ppm (d, J = 17 Hz, 1H);

7.2 ppm (s, 3H); 7.4 ppm (d, J = 17 Hz, 1H).

1.2 Preparation of 3-(2.2-difluorobenzodioxol-4-yl)-4-cvano<p>yrrole

A solution of 38.8 g of the aforementioned cinnamonitrile and 43.4 g of p-toluenesulfonylmethyl isocyanide (tosmic) in 250 ml of tetrahydrofuran and a solution of 29.2 g of potassium tert-butylate in 250 ml of tetrahydrofuran are each added dropwise at -5°C from two dropping funnels to 100 ml of tetrahydrofuran. The mixture is then stirred for 1 hour at 0°C and for a further 2 hours at room temperature. The reaction mixture is then poured into ice water and extracted twice with ethyl acetate. The organic extracts are washed four times with a half-saturated solution of sodium chloride, dried over sodium sulfate, stirred with silica gel, a small amount of activated carbon and diatomaceous earth ("Celite") and filtered, and the filtrate is concentrated. The residue is crystallized from a small amount of methylene chloride at -30oC, giving 16.5 g of beige crystals with a melting point of 197-199°C.

1.3 Preparation of 1-acetyl-3-(2.2-difluorobenzodioxole-4-vl)-4-cyanopyrrole

0.2 g of 4-dimethylaminopyridine and 1.6 ml of triethylamine are added to a solution of 2.5 g of the aforementioned pyrrole in 10 ml of tetrahydrofuran. A solution of 0.85 ml of acetyl chloride in 5 ml of tetrahydrofuran is then slowly added dropwise at -10°C. The reaction mixture is stirred for 16 hours in an ice bath and then filtered, and the filtrate is concentrated. The solid residue is recrystallized from a mixture of toluene and petroleum distillate, and gives crystalline N-(acetyl)-3-[2,2-difluorobenzodioxol-4-yl]-4-cyanopyrrole with a melting point of 133-135°C.

Compounds 1.3 to 1.32 indicated in the table are prepared in an analogous manner.

2. Formulation examples for liquid active agents of formula I (the percentages are listed as % by weight)

Emulsions of any desired concentration can be prepared from such concentrates by dilution with water.

These solutions are suitable for application in the form of microdroplets.

The active agent is dissolved in methylene chloride, the solution is sprayed onto the support and the solvent is then evaporated in vacuo.

Ready-to-use powder obtained by thoroughly mixing the berries with the active agent.

The active agent is thoroughly mixed with the additives and the mixture is ground thoroughly in a suitable mill, giving wettable powders which can be diluted with water to give suspensions of the desired concentration.

Emulsions of any desired concentration can be obtained from this concentrate by dilution with water. Ready-to-use dust is obtained by mixing the active agent with the carrier, and grinding the mixture in a suitable mill.

The active agent is mixed and ground with the additives, and the mixture is then moistened with water. The mixture is extruded and dried in an air stream.

The finely ground active agent is added uniformly in a mixture to kaolin moistened with polyethylene glycol. Non-dusty coated granules are obtained in this way.

2. 10 Suspension concentrate

The finely ground active agent is thoroughly mixed with the additives, giving a suspension concentrate from which suspensions of any desired concentration can be obtained by dilution with water.

3. Biological Examples

Example 3. 1: Effect against Puccinia graminis on wheat

a) Residual pollutant effect

Wheat plants are treated 6 days after sowing with a spray mixture (0.02% active agent) prepared from a wettable powder formulation of the test compound. After 24 hours, the treated plants are infected with a uredospore suspension of the fungus. The infected plants are incubated for 48 hours at 95-100% relative humidity and approx. 20°C and then placed in a greenhouse at approx. 22°C. Evaluation of rust pustule development is done 12 days after infection.

b) Systemic effect

Wheat plants are treated 5 days after sowing with a spray mixture (0.006% active agent, based on the volume of soil) prepared from a wettable powder formulation of the test compound. After 48 hours, the treated plants are infected with a uredospore suspension of the fungus. The plants are then incubated for 48 hours at 95-100% relative humidity and approx. 20°C and then placed in a greenhouse at approx. 22°C. Evaluation of rust pustule development is done 12 days after infection.

Compounds from Table 1 showed a good effect against Puccinia fungi. Puccinia attack was 100% on untreated and infected control plants. Compounds 1.2, 1.15, 1.24, 1.30 and 1.32 and others inhibited the Puccinia attack to 0 to 5%.

Example 32.: Effect against Cercospora arachidicola in peanut plants

Residual protective effect

Peanut plants 15 cm in height are sprayed with a spray mixture (0.006% active agent) prepared from a wettable powder formulation of the test compound, and are infected 48 hours later with a conidia suspension of the fungus. The infected plants are incubated for 72 hours at approx. 21°C and high humidity and then placed in a greenhouse until typical leaf spotting occurs. Evaluation of the fungicidal effect is done 12 days after infection and was based on the number and size of the spots.

Compared to untreated and infected control plants (number and size of spots = 100%), Cercospora attack on peanut plants treated with the compounds of Table 1 was significantly reduced. Thus compounds 1.1, 1.2 and 1.15 inhibited the formation of spots almost completely in the above experiments.

Example 3. 3: Effect against Erysiohe araminis on barley Residual protective effect

Building plants approx. 8 cm in height is sprayed with a spray mixture (0.02% active agent) prepared from a wettable powder formulation of the test compound. The treated plants are pollinated with conidia of the fungus after 3 to 4 hours. The infected barley plants are placed in a greenhouse at approx. 22°C. The fungal attack is evaluated after 10 days. Compounds from Table 1 were very effective against Erysiphe attack on barley.

Example 3. 4: Residual protective effect against Venturia inae qualis on apple shoots

Apple cuttings with 10-20 cm long fresh shoots are sprayed with a spray mixture (0.06% active agent) prepared from a wettable powder formulation of the test compound. The plants are infected 24 hours later with a conidia suspension of the fungus. The plants are then incubated for 5 days at 90-100% relative humidity and placed in a greenhouse for a further 10 days at 20°-24°C. The evaluation of the wart infestation is done 1 to 5 days after infection.

Compounds from Table 1 showed good activity against Venturia on apple shoots. Compounds 1.1, 1.2, 1.15, 1.24, 1.30 and 1.32 reduced attack to less than 10%. Venturia attack on untreated and infected shoots was 100%.

Example 3. 5: Effect against Botrytis cinerea on beans Residual protective effect

Bean plants approx. 10 cm in height is sprayed with a spray mixture (0.02% active agent) prepared from a wettable powder formulation of the test compound. After 48 hours, the treated plants are infected with a conidia suspension of the fungus. The infected plants are incubated for 3 days at 95-100% relative humidity and 21°C and then evaluated for fungus attack. The compounds from Table 1 inhibited the fungus infection very strongly in many cases. At a concentration of 0.02%, compounds 1.1, 1.2, 1.15, 1.24, 1.30 and 1.32 were fully effective (0 to 5% attack). Fungus attack was 100% on untreated and infected bean plants.

Example 3. 6 Effect against Botrytis cinerea on apples

Artificially damaged apples were treated by dripping a spray mixture prepared from a wettable powder formulation of the test compound on the damaged areas. The treated fruit is then inoculated with a spore suspension of Botrytis cinerea and incubated for 1 week at high humidity and approx. 20°C. The evaluation is carried out by counting the number of damaged areas attacked by rot and deriving the fungicidal effect of the test compound from there. Compounds from Table 1 were very effective against Botrytis attack on apples. Compared to untreated controls (100% attack), compounds 1.1, 1.2, 1.15, 1.24, 1.30 or 1.32 and others inhibited the fungus attack almost completely.

Example 3. 7. : Effect against Alternaria solani on tomatoes

After a cultivation period of 3 weeks, tomato plants are sprayed with a spray mixture (0.06% active agent) prepared from a wettable powder formulation of the test compound. After 24 hours, the tomato plants are treated with a conidia suspension of the fungus. Evaluation of fungicidal effect is done on the basis of the fungus attack after the plants have been incubated for 8 days at high humidity and a temperature of 18°-22°C. Compounds from Table 1 reduced Alternaria attack. considerably; thus compounds 1.1, 1.2, 1.15, 1.24, 1.30 or 1.32 inhibited the attack completely (0 to 5%).

Example 3. 8. : Effect against Pyricularia on rice plants Residual protective effect

After a cultivation period of 2 weeks, rice plants are sprayed with a spray mixture (0.02% active agent) prepared from a wettable powder formulation of the test compound. After 48 hours, the treated plants are infected with a conidia suspension of the fungus. Evaluation of the fungus attack is done after incubation for 5 days at 95-100% humidity and 24°C.

Compounds from Table 1 effectively inhibited Pyricularia attack. This reduced e.g. compounds 1.1,1.2,1.15, 1.24, 1.30 and 1.32 attacked to less than 10%.

Example 3. 9.: Effect against Fusarium nivale in rye

Rye seed of the Tetrahell variety which is naturally infected with

Fusarium nivale is treated on a mixer roller with the experimental fungicide at a concentration of 60 ppm active agent (based on the weight of the seeds). The infected and treated rye is sown in the open in October with a seeding machine on pieces of land 3 meters long and in 6 rows. Three replicates are performed with each test compound. Until evaluation is made, the test plants are grown under normal field conditions (preferably in an area with unbroken snow cover during the winter months. To determine the effectiveness of the test compounds, the percentage of plants attacked by Fusarium is determined in the spring directly after the snow has melted.

Compounds from Table 1 showed good activity against Fusarium on rye in this experiment. On the other hand, Fusarium attack on untreated and infected control plants is 100%.

Example 3. 10.: Effect against Helminthosporium <g>ramineum on barley

Seeds of winter barley of the "Cl" variety naturally infected with Helminnthosporium gramineum were treated on a mixer roller with the test fungicide at a concentration of 60 ppm of active agent (based on the weight of the seeds). The infected and treated barley is sown in the open in October with a seeding machine on pieces of soil 2 meters long and in 3 rows. Three replicates are performed with each test compound. Until evaluation is done, the test plants are grown under normal field conditions. To determine the effectiveness of the test compounds, the percentage of stems attacked by Helminthosporium when the axes emerge is determined.

Compounds from table 1 showed good activity against Helminthosporium in this experiment. On the other hand, the Helminthosporium attack on untreated and infected control plants was 100%.

Example 3. 11. : Effect against Tilletia caries in wheat

Seeds of winter wheat of the Probus variety that were artificially infected with fire spores of Tilletia caries (3 g of dry spore material per 1 kg of seed) are treated on a mixer roller with the experimental fungicide at a concentration of 60 ppm active agent (based on the weight of the seeds). The infected and treated wheat is sown in the open in October with a seed drill on plots 2 meters long and in 3 rows. Three replicates are performed with each test compound. To determine the effectiveness of the trial compounds, the percentage of ears attacked by Tilletia at ear maturation is determined.

The compounds from table 1 showed good activity against Tilletia in this experiment. On the other hand, the Tilletia attack on untreated and infected control plants was 100%

Experiment 3. 12. : Biological experiment

In the following, test methods and results for

compound no. 1.1 (non-acylated pyrrole derivative) and no. 1.2 (acylated pyrrole derivative) according to the present invention with regard to their microbicidal activity compared to the structurally closest known compounds A and B (DE-A-29 27 480):

Connection No. 1.1

3-cyano-4-(2,3-difluoromethylenedioxyphenyl)pyrrole Compound A according to DE-A-29 27 480

3-cyano-4-(2,3-dichlorophenyl)-pyrrole

Connection No. 1.2

1-acetyl-3-cyano-4-(2,3-difluoromethylenedioxyphenyl)-pyrrole Compound B according to DE-A-29 27 480

1-Acetyl-3-cyano-4-(2,3-dichlorophenyl)-pyrrole

The compounds were formulated as 25% spray powder (WP 25) and in the form of diluted aqueous preparations with active substance concentrations of 200 ppm, 60 ppm, 20 ppm, 6 ppm and 0.6 ppm were subjected to the following tests. Per active substance concentration, 3 plants were treated.

Each plant was assessed separately, and the mean value of three assessments was calculated.

Grade scale; 1 = 0-5% fungal attack (hardly visible attack)

3 = 5-20% attack

6 = 20-50% attack

9 = over 50% attack (connection inactive)

Experiment I; Effect on Botrytis cinerea in apples

Artificially damaged apples are treated by dripping a spray solution made from a spray powder with the active ingredient on the damaged areas. The treated fruits are then inoculated with a spore suspension of Botrytis cinerea and incubated at high humidity at about 20°C.

During the assessment, the rotten, damaged areas and their size are assessed, and the fungicidal effect of the test substance is derived from this.

Trial II; Effect on Alternaria solani in tomatoes

Tomato plants are sprayed after three weeks of culture with a spray liquid made from a spray powder with the active ingredient. After 24 hours, the tomato plants are infected with a conidia suspension of the fungus.

The evaluation of the fungicidal effect takes place on the basis of the fungal attack after an incubation of the infected plants for 8 days in high humidity at a temperature of 18-22°C.

Trial III; Effect on Rhozoctonia solani (earthworms on rice plants)

Protective local foliar application

12-day-old rice plants are sprayed with a spray liquid made from a formulation with the active ingredient. One day later, the treated plants are infected with a suspension of mycelium and sclerotia of R. solani. After 6 days of incubation at 27°C (the day) or 23°C (at night) and 100% rel. humidity (humidity box) in the climate chamber, the fungal attack on the leaf sheath, leaves and stem is assessed. For the two comparison pairs of compounds, the following result was obtained: Result

It is clear that the active substances according to the present invention exhibit an effect up to 30 times better than the known, structurally closest compounds.

Claims (1)

Compound, characterized by formula I in which X has the following meaning: hydrogen or CO-R^, in which R^ is C^^-Cg-alkyl which is unsubstituted or substituted by halogen or C^-C3-alkoxy: or is C3-C6 -alkenyl, C 3 -C 6 -alkynyl, or C 1 -C 8 -alkoxy which are unsubstituted or substituted by halogen or C 1 -C 3 - alkoxy; or is C3-C8-alkenyloxy, C3-C6-cycloalkyl or tetra-hydrofur-2-yl; 2. Compound of formula According to claim 1, characterized in that it is selected from the group consisting of 3-(2,2-difluorobenzodioxol-4-yl)-4-cyanopyrrole; 1-acetyl-3-(2,2-difluorobenzodioxol-4-yl)-4-cyanopyrrole; 1-methoxyacetyl-3-(2,2-difluorobenzodioxol-4-yl)-4-cyano-pyrrole; 1-methoxycarbonyl-3-(2,2-difluorobenzodioxol-4-yl)-4-cyanopyrrole; 1-allyloxycarbonyl-3-(2,2-difluorobenzodioxol-4-yl)-4-cyanopyrrole; 1-n-propoxyacetyl-3-(2,2-difluorobenzodioxol-4-yl)-4-cyanopyrrole. 3. Compound characterized in that it is 2,3-(difluoromethylenedioxy)cinnamic nitrile. 4. Microbial mixture for the control of microorganisms or to protect living plants from attack by said microorganisms and/or to preserve easily perishable storage goods of vegetable or animal origin, characterized in that the mixture contains as active component at least one compound as defined in claim 1 5. Mixture according to claim 4, characterized in that it contains at least one active compound as defined in claim 2.