NO753923L - - Google Patents

Description

The invention relates to new 2,3-dihalo-alkanoyl-[_thio/-urethanes and their use as fungicides.

It is already generally known that zinc-ethylene-1,2-bis-dithiocarbamidate and N-trichloromethylthio-tetra-hydrophthalimide are used as fungicides against phytopathogenic fungi. As commercial products, the compounds mentioned have gained worldwide expansion in plant protection and can be described as standard preparations (details of the compounds can be found in "Chemie der Pflanzenschutz- und Schådlingsbekåmpf-ungsmittel", volume 2, pages 65 and 108, published by R. Wegler, Springer -Verlag Berlin/Heidelberg/New York (1970)). However, the effect of the indicated compounds is not always satisfactory, especially at lower amounts used.

It has now been found that the new 2,3-dihalo-alkanoyl-1_thio/-urethanes of formula

in which

R and R' mean hydrogen or alkyl,

R" means aryl, benzyl or alkyl, these being

residues may be substituted,

Hal means chlorine or bromine and

X means oxygen or sulphur

has strong fungicidal properties.

The 2,3-dihalo-alkanoyl-1-thio/-urethanes of formula I are obtained when the 2,3-dihalo-alkanoyl isocyanate of formula in which R, R' and Hal have the above meaning is reacted with a compound of formula

in which

R" and X have the above meaning.

Surprisingly, the 2,3-dihaloalkanoyl-/_thio/- urethanes according to the invention show a considerably higher fungicidal effect than the above-mentioned known commercial products. The substances according to the invention are thus an enrichment of the technique.

If 2,3-dibromo-propionyl isocyanate and phenol are used as starting materials, the course of the reaction can be reproduced by the following formula:

The 2,3-dihalo-alkanoyl-isocyanates required for the production of 2,3-dihalo-alkanoyl-1-thio7-urethanes of formula I are generally defined by the general formula II.

In this formula, R and R' consist, preferably, of hydrogen or alkyl with up to 5 carbon atoms and Hal, by definition, means chlorine or bromine.

The compound of formula II is not yet known.

They can be prepared, preferably in inert solvents, e.g. halohydrocarbons, mixes corresponding alkene-carboxylic acid amides, such as e.g. acrylic acid amide, preferably in the temperature range -10 and +30°C with chlorine or bromine and reacting the formed adduct, optionally without its intermediate isolation, with oxalyl chloride, carrying out the latter reaction, preferably between +50 and 100°C. Thereby, the desired starting products with formula II are formed during the splitting off of halogen hydrogen and carbon monoxide (compare to this also the information in the preparation examples). As examples of the compounds of formula II, the following should be mentioned: 2,3-dibromo-propion isocyanate, 2,3-dichloro-propion isocyanate, 2,3-dibromo-2-methyl-propion isocyanate, 2,3-dichloro-2- methyl propion isocyanate, 2,3-dibromo-butyryl isocyanate, 2,3-dichlorobutyryl isocyanate, 2,3-dichloro-2-methyl-butyryl isocyanate, 2-, 3-dibromo-n-pentanoyl isocyanate, 2,3 -dichloro-n-octanoisocyanate.

In the case of the further compounds of formula III required as starting products, these are alcohols,

phenols and naphthols and on their corresponding sulfur analog compounds. The compounds are generally defined by formula III. In this formula, R" preferably means aromatic residues with up to 10 carbon atoms, as examples the phenyl and naphthyl residues should be mentioned. As possible substituents for aryl, it is preferable to mention: Alkyl and alkoxy with in-

to 8 carbon atoms, such as e.g. methyl, tertiary butyl and methoxy; phenyl (i.e. R" as a whole means the radical biphenylyl); the phenoxy radical; halogen, such as, for example, fluorine, chlorine or bromine, the methylmercapto- and methylsulfonyl group; further substituents are preferably nitro-, methoxycarbonyl-, ethoxycarbonyl- and phenoxycarbonyl- the group, the aldehyde group, the acetyl and benzoyl group, then the acetylamino group, furthermore the haloalkyl group with up to 2 carbon and up to 5 halogen atoms is mentioned, as an example the trifluoromethyl group should be mentioned. In addition, R" can also mean benzoyl and' for alkyl and haloalkyl with preferably up to 4 carbon atoms. X preferably means oxygen.

Those under .the general formula III falling alcohols, thioalcohols, phenols, naphthols and. thiophenols and their derivatives are known. Examples include: Phenol, 4-chloro-phenol, 2-chloro-phenol, 2,4-dichloro-phenol, 2,4,5-trichloro-phenol, 4-bromo-phenol, 2,4,6-tribromo -phenol, 4-fluoro-phenol, 4-iodo-phenol, 4-tert.-butyl-phenol, 2,6-di-ethyl-phenol, 2,6-diisopropyl-phenol, 4-chloro-2-methyl- phenol,•4-nitro-phenol, 2-chloro-^-nitro-phenol, 2-methyl-4-nitro-phenol, 2,4-dinitro-6-methyl-phenol, 4-methylmercapto-3- methyl-phenol , 4-methylsulfonyl-phenol, 2-, 3- and 4-acetylamino-phenol, 3-methyl-4-tert.-butyl-phenol, 2-hydroxy-biphenyl, 4- hydroxy-biphenyl, salicylic acid methyl ester, salicylic acid phenyl- ester, 5-methyl-2-hydroxy-benzoic acid methyl ester, 5-chloro-2-hydroxy-benzoic acid methyl ester, salicylaldehyde, 4-chloro-salicylaldehyde, 2-hydroxy-acetophenone, 4-hydroxy-acetophenone, 4-hydroxy- benzophenone; 1-naphthol, 2-naphthol, 4-acetylamino-1-naphthol, 5-methoxy-1-naphthol, 1-chloro-2-naphthol, 3-hydroxy-diphenylene oxide, thus benzyl alcohol; also methanol, ethanol, 2-chloroethanol, 2-bromoethanol, n-butanol, sec.-butahol.l, isobutanol, tert.-buta-no.l; further the following' thio-compounds: Thiophenol, 2- and k-thiocresol, 4-tert.-butyl-thiophenol, 4-chloro-thiophenol, 4-acetylamino-thiophenol, 2-acetylamino-thiophenol, 4-bromo-thiophenol, 4 -mercapto-bipheny1, 4-nitrb-thiophenol, 2-mercapto-benzoic acid methyl ester, 1-mercapto-naphthalene, 4-acetylamino-l-mercapto-naphthalene, 2-chloro-4-acetylamino-thiophenol, methyl mercaptan, butyl mercaptan, benzyl mercaptan .

As a diluent, it comes for turnover

of the compounds of formula II with the compounds of formula III in terms of organic solvents which are indifferent to acyl isocyanates. This preferably includes hydrocarbons such as e.g. petroleum ether, ligroin and petrol in the boiling range between 40 and 150°C, further benzene, toluene and chlorobenzene, further chlorinated alkanes such as dichloromethane, trichloromethane, carbon tetrachloride or 1,2-dichloroethane, further ethers, such as diethyl. ether, further acetonitrile, dimethylformamide and ketones such as acetone.

The reaction temperatures can be varied within a large range. Generally, one works between -20 and +100°C, preferably between 0 and 30°C.

When carrying out the method according to the invention, preferably 1.0 to 1.1 mol of acyl isocyanate with formula II is used per 1 mol of the hydroxy or mercapto compound according to formula III, however, under- or excesses of up to 20% can be made without significant yield - hallway. Further information on the reaction can be found in the production examples, the work-up takes place in a simple way by separating the reaction products, which crystallize out of this with a suitable choice of solvent and are mostly the analytes. In other cases, it is possible with suitable precautions such as evaporation of the solution and recrystallization of. isolation and purification of the residue is achieved. In all cases must

the absence of moisture and solvents containing hydroxyl groups in the reaction mixture is ensured in order to avoid side reactions with the acylisocyanate reactant.

The active substances according to the invention have a strong fungitoxic effect. Their small warm-blooded toxicity and good tolerance for higher plants enable their use as a plant protection agent against fungal-like diseases.

They do not damage cultivated plants in the concentrations required to combat fungi...' Fungitoxic agents in plant protection are used to combat fungi from the most diverse classes of fungi such as Archimycetes, Phycomycetes, Ascomycetes, basidiomycetes and Fungi imperfecti.

The active substances according to the invention can be used against parasitic fungi on plant parts above ground, tracheomycosis-producing fungi which attack the plants from the soil, seed-transmitted fungi and soil-dwelling fungi. They are particularly effective against Phycomycetes, ascomycetes and basidiomycetes. As important fungi that can be combated with the active substances according to the invention, the following should be mentioned in detail: Phytophthora infestans, Fusicladium dendriticum and Puccinia recondita.

The active substances according to the invention can be transferred in the usual formulations such as solutions, emulsions, suspensions, powders, pastes and granules. These are produced in a known manner, e.g. by mixing the active substance with emollients, i.e. liquid solvents, pressurized liquefied gases and/or solid carriers, possibly using surface-active agents, i.e. emulsifiers and/or dispersants and/or foam-producing agents. In the case of using water as a suspending agent, it can e.g. organic solvent is also used as auxiliary solvent. Liquid solvents are essentially: aromatics such as xylene, toluene, benzene or alkylnaphthalenes, chlorinated aromatics or chlorinated aliphatic hydrocarbons, such as chlorobenzenes, chloroethylenes or methylene chloride, aliphatic hydrocarbons such as cyclohexane or paraffins, e.g. petroleum fractions, alcohols such as butanol or glycol and their ethers and esters, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone or cyclohexanone, strongly polar solvents such as dimethylformamide and dimethyl sulfoxide and water. By liquefied gaseous suspending agents or carriers are meant such liquids which are gaseous at normal temperature and under normal pressure, e.g. aerosol propellants, such as dichlorodifluoromethane or trichlorofluoromethane, as solid carriers: natural stone flour, such as kacDlin, clay soil, talc, chalk, quartz, attapulgite, montmorillonite or diatomaceous earth and synthetic stone flour such as highly dispersed silica, alumina and silicates; as emulsifier

agents: non-ionic and anionic emulsifiers such as polyoxyethylene fatty acid esters, polyoxyethylene fatty alcohol ethers, e.g. alkylaryl polyglycol ethers, alkyl sulphonates, alkyl sulphates or aryl sulphonates, as dispersants: e.g. lignin, sulphite liquor and methyl cellulose.

The active substances according to the invention can be present in the formulation in admixture with other known active substances such as fungicides, insecticides and acaricides.

The formulations usually contain between 0.1

and, 95% by weight active substance, preferably between 0.5 and 90%.

The active substances can be used as such

in the form of their formulations or the applications prepared from them such as ready-to-use solutions, emulsions, suspensions, powders, pastes and granules. The application takes place in the usual way, e.g. by showering, spraying, spraying, spreading and pouring.

The active substances according to the invention are usually sufficiently effective at active substance concentrations between 0.0001 and 0.05%. When using aqueous active substance preparations, the active substance concentrations can fluctuate within larger ranges and are then roughly between 0.0005 and 2.0%. Are the active substances delivered according to special delivery methods, e.g. according to the ULV method (ultra-low volume), the active substance concentrations are higher, e.g. between 20 and 80%.

The active substances according to the invention also show a microbicidal effect.

The application possibilities can be seen from the following six application examples.

Example A.

Mycelial growth test.

Nutrient base used:

20 parts by weight agar-agar

200 parts by weight potato decoction

5 parts by weight ground

15 parts by weight dextrose

5 parts by weight peptone

2 parts by weight disodium hydrogen phosphate

0.3 parts by weight of calcium nitrate.

Ratio between amount of solvent and nutrient base:

2 parts by weight solvent mixture

100 parts by weight. agar nutrient base..

Composition of the solvent mixture:

0.19 parts by weight DMF or acetone

0.01 parts by weight emulsifier alkyl-aryl-polyglycol ether 1.80 parts by weight water

2.00 parts by weight solvent mixture.

The amount of active substance necessary for the desired concentration of active substance in the nutrient medium is mixed with the specified amount of solvent mixture. . Furthermore, control plates are set up without preparation admixture.

When the nutrient base has cooled and solidified, inoculate the plates

with the mushroom types indicated in the table and incubated at approx. 21°C.

The assessment takes place according to the mushroom's growth rate after 4-10 days. During the assessment, the ■ radial mycelial growth on the treated nutrient medium is compared with the growth on the control nutrient medium. The assessment of mushroom growth takes place with the following figures:

1 no fungal growth

up to 3 very strong inhibition of growth

up to 5 moderately strong inhibition of growth

up to 7 slight inhibition of growth

9 ' growth corresponds to untreated controls.

-Active substances, active substance concentrations

and results can be seen from the following table:

Example B. Fusicladium sample (apple)/protective.

Solvent: 4.7 parts by weight of acetone

.Emulsifier: 0.3 parts by weight alkyl-aryl-polyglycol ether Water: 95.0 parts by weight

The amount of active substance required for the desired concentration of active substance in the spray liquid is mixed with the indicated amount of solvent and the concentrate is diluted with the indicated amount of water containing the aforementioned additives.

With the spray liquid, young apple seedlings that are in the fourth to sixth leaf stage are sprayed to droplet moisture. The plants remain for 24 hours at 20°C and a relative humidity of 70% in the greenhouse. They are then inoculated with an aqueous conidial suspension of the apple scab producer (Fusicladium dendriticum) and incubated for 18 hours in a humidity chamber at 18 - 20°C and 100% relative humidity.

The plants then return to the greenhouse for 14 days. 15 days after inoculation, the attack on the seedlings is determined. The formed assessment values are converted into % attack. 0% means no attack, 100% means that the plants are completely infected.

Active substances, active substance concentrations and results appear in the following table:

Example C. Phytophthora test (tomatoes)/protective.

The amount of active substance required for the desired concentration of active substance in the spray liquid is mixed with the indicated amount of solvent and the concentrate is diluted with the indicated amount of water containing the aforementioned additives.

With the spray liquid, young tomato plants with 2 to 4 leaves are sprayed until the moisture level drops to a drop. The plants remain for 24 hours at 20°C and a relative humidity of 70% in the greenhouse. The tomato plants are then inoculated with an aqueous spore suspension of Phytophthora infestans. The plants are brought into a humidity chamber with 100% humidity and a temperature of 18 - 20°C.

After 5 days, the attack on the tomato plants is determined. The assessment values obtained are converted to percentage attack.

0% means no infestation, 100% means the plants are completely infected...

Active substances, active substance concentrations and results appear in the following table.

Example D. Germination treatment sample/grain rust/protective

(leaf-destroying mycosis).

For the preparation of a suitable active substance preparation, 0.25 parts by weight of active substance are taken up in 25 parts by weight of dimethylformamide and 0.06 parts by weight of emulsifier (alkyl-aryl-polyglycol ether) and 975 parts by weight of water are added. The concentrate is diluted with water to the desired final concentration in the spray liquid.

To investigate the protective effect, one-leaf wheat seedlings of the Michigan Amber type are inoculated with a uredospore suspension of Puccinia recondita in 0.1% water agar. After the spore suspension has dried, the wheat plants are sprayed with the active substance preparation, moist with dew, and set aside for incubation for 24 . hours at 20 o C and a 100%„, -i.g humidity in a greenhouse.

After 10 days of residence of the plants at a temperature of 20°C and a humidity of 80 to 90%, the attack on the plants with rust pustules is assessed. The degree of attack is expressed as a percentage of the attack of untreated control plants. Here, 0% means no attack and 100% the same degree of attack as in the untreated controls. The active substance is all the more effective the less the rust attack.

Active substances, active substance concentrations in the spray liquid and degrees of attack are shown in the following table:

Example E. Seed stain test/stripe disease in barley.

(seed-borne mycosis).

To prepare a suitable dry mordant, the active substance is ground with a mixture of equal parts by weight of talc and diatomaceous earth to a finely powdered mixture with the desired active substance concentration.

For pickling, barley seed material that is naturally infected with Drechslera graminea (formerly known as Helminthosporium gramineum) is shaken with the pickling agent in a closed glass bottle. The seed material is placed on moist filter discs in closed Petri dishes in a refrigerator for 10 days at a temperature of 4°C This starts the germination of the barley and possibly also the germination of the fungal spores. The pre-germinated barley is then sown with 2 x 50 grains 2 cm deep in Fruhstorfer unit soil and cultivated in a greenhouse at temperatures around 18°C in seed boxes, which are exposed to 16 hours of light daily Within 3 to 4 weeks, the typical symptoms of stripe disease develop.

After this time, the number of diseased plants is determined as a percentage of the total number of plants grown. The active substance is all the more effective the fewer plants that are sick.

Active substances, active substance concentrations in the mordant, amount of mordant used and number of diseased plants appear in the following table:

Manufacturing examples. Example 1.

51 g (0.2 mol) of 2,3-dibromo-propionyl isocyanate is added dropwise at 10 to 30°C during 15-30 minutes with stirring to a solution of 20 g (0.21 mol) of phenol in 300 ml of benzene ; stirring for 15 minutes, adding approximately the same volume of petroleum ether and suctioning off the precipitated reaction product and washing it with petroleum ether. 60 g (85% of the theoretical) of phenyl-N-(2,3-dibromo-propionyl)-urethane of melting point 172 - 173°C are obtained. Preparation of the precursor: 100 g (1.4 l mol) acrylic acid amide is dissolved in 1200 ml chloroform and at a temperature of 0 - 5°C, 224 g (1.4 l mol) bromine, dissolved in 250 ml, are added dropwise to the solution while stirring chloroform. The resulting suspension is stirred for a further 5 hours at 20°C. Then, with further stirring, 270 g (2.13 mol) of oxalyl chloride are added dropwise and the reaction mixture is then heated to boiling and kept under reflux at boiling temperature until the evolution of gas has ended. The reaction mixture is then fractionally distilled; 220 g (61% of the theoretical) of 2,3-dibromo-propionyl isocyanate of boiling point 73-75°C/2.5 torr are thus obtained.

Example 2.

To a solution of 17.0 g (0.1 mol) 2-hydroxy-biphenyl in 200 ml benzine is added dropwise at 10 to 15°C a solution of 17.0 g (0.1 mol) 2,3-dichloro -propionyl isocyanate in 20 ml benzine. Thereby the reaction product crystallizes out. The mixture is stirred for another 1 hour at 20°C, diluted with petroleum ether, filtered and dried. Yield 28.0 g of O-(2-biphenyl)-N-(2,3-dichloro-propionyl)-urethane (8~5% of theory). After recrystallization from toluene-petroleum ether, the compound melts at 125 to 128°C.

Preparation of the preliminary product:

In a solution of 100 g (1.4 l mol) of acrylic acid

amide in 1000 ml of chloroform is introduced while stirring at approx. 0 to 5°C 99 g' (1.40 mol) chlorine. It is then stirred for 3 hours at approx. 20°C and then add, with further stirring, 270 g (2.13 mol) of oxalyl chloride. The solution is then heated under reflux to boiling, until gas evolution has ended. Fractional distillation of the reaction solution yields 172 g (72% of the theoretical) of 2,3-dichloro-propionyl-isocyanate

nat of boiling point 38-4l°C7l,0. dry. Example 3•

A solution of 27.0 g (0.105 mol) 2,3- dibromo-2-methyl-propionyl isocyanate in 20 ml of benzene. The mixture is stirred for a further 12 hours at 20°C, the solution of the reaction product is evaporated in vacuo and the oily residue is brought to crystallization by stirring with petroleum ether. Then suction off, wash with petroleum ether and dry. Yield: 35.0 g of O-(2,4-dichloro-phenyl)-N-(2,3-dibromo-2-methylpropionyl)-urethane of melting point 93 - 97°C (81% of the theoretical). Preparation of the precursor: In a solution of 100 g (1.17 mol) methacrylic acid amide in 1000 ml of chloroform, at a temperature of approx. 0 to 5°C with stirring 189 g (1.2 mol) bromine in 200 ml chloroform. The reaction mixture is stirred for a further 3 hours at approx. 20°C and then 228 g (1.8 mol) of oxalyl chloride are added dropwise. It is then heated under reflux for a long time at boiling temperature, until gas evolution has ended. Fractional distillation of the reaction mixture yields 248 g (65% of the theoretical) 2,3-dibromo-2-methyl-propionyl isocyanate of boiling point 66 to 70°C7 2.5 torr.

Example 4.

26.0 g (0.1 mol) of 2,3-dibromo- propionyl isocyanate, dissolved in 100 ml of white spirit (boiling point 60 to ;80°C). The reaction product crystallizes after a short time. Stirring is continued for another 3 hours at 20°C, the mixture is diluted with 200 ml of petroleum ether ■ (boiling point 40 to 60°C), filter off, clean with petroleum ether and dry. You thus get 29 g of 0-(2-chloro-ethyl)-N-(2,3-dibromo-propionyl)-urethane (86% of the theoretical ).of melting point 129.- 131°C.

Example 3-

To a solution of 20.0 g (0.14 mol) 4-chlorothiophenol in 200 ml dry benzene is added dropwise at 0 to 5°C 36 g (0.14 mol) 2,3-dibromo-propionyl isocyanate, dissolved in 50 ml of benzene. The reaction product begins to crystallize after 2 hours at 20°C. After 4 hours, dilute with the same volume of petroleum ether, filter, wash with petroleum ether and dry. The yield amounts to 39 g of S-(4-chloro-phenyl)-N-(2,3-dibromo-propionyl)-urethane (70% of the theoretical) of melting point 182 - 183°C during decomposition.

Corresponding to the information in the manufacturing examples.

1 to 5, the following compounds with the general formula can be prepared

Claims (3)

1. 2, 3_dihalo-alkanoyl-/_thio/-urethanes with fungicidal properties and formula in which R and R' mean hydrogen or alkyl, R" means aryl, benzyl or alkyl, as these residues may be substituted, Hal means chlorine or bromine and X means oxygen or sulphur. 2. Fungicidal agent, characterized by the content of at least one 2,3-dihalo-alkanoyl-A thio/-urethane according to claim 1. 3. Use of 2,3-dihalo-alkanoyl-/_thio/-urethanes according to claim 1 for combating fungi.