DE2118470A1 - S-phenyl-s-alkyl-o-alkyl-dithiophosphoric acid esters - prepd by reaction of s-phenyl-o-alkyl-thiophosphoric acid chloride with mercap - Google Patents

Abstract

Cpds. of general formula (I) Cl-CH2-CRNO2-CH2-O-POSR'SR" where R and R' = alkyl (max. 6C) R" = phenyl opt. mono- or poly-substd. with halogen or alkyl (max 4C); are prepd. by reacting a cpd. (II) Cl-CH2-CRNO2-O-POSR" Cl with a cpd. (III) R'SH in the form of salts or in the presence of acid-binding agents. Reaction is pref. at 20-60 degrees C using excess (III). (I) have strong fungitoxic activity without phytotoxicity for cultures and with low mammalian toxicity. They may be used as plant-protection agents against parasitic moulds attacking plants above- and below the soil level. They are esp. active against Piricularia oryzae showing not only protective but also curative and systemic effects. They may also be used as seed disinfectants or as soil treatment agents against phytopathogenous fungi. (I) have also insecticidal action.

Description

S-Phenyl-S-alkyl-O-alkyl-dithiophosphoric acid ester, process for their Manufacture and their use as fungicides The present invention relates to new S-phenyl-S-alkyl-O-alkyl-dithiophosphoric acid ester, which has a fungicidal effect have, and a process for their preparation.

It has already become known that O, O-dialkyl-S-phenylthiolophosphoric acid ester, such as the O, O-diethyl-S-j nitrophenyl7-thiolophosphoric acid ester, fungicidal properties (val, U.S. Patent 2,690,450). However, the effect is at low levels Application rates unsatisfactory.

It has now been found that the new S-phenyl-S-alkyl-O-alkyl-dithiophosphoric acid esters of the formula in which R and R 'stand for alkyl with up to 6 carbon atoms and R "stands for phenyl, which can optionally be substituted one or more times by halogen or alkyl with up to 4 carbon atoms, are characterized by a strong fungicidal activity.

It has also been found that the new S-phenyl-S-alkyl-O-alkyl-dithiophosphoric acid esters of the constitution (I) are obtained if S-phenyl-O-alkyl-thiophosphoric acid ester chlorides of the formula in which R and R ″ have the meaning given above, with mercaptans of the formula R'SH (III) in which R 'has the meaning given above, in the form of their salts or in the presence of acid binders.

Surprisingly, the 5-phenyl-S-alkyl-O-alkyl-dithiophosphoric acid esters according to the invention show a higher fungicidal effect than previously known compounds. That's how it is in comparison Fungicidal superior to 0,0-diethyl-S-ZE-nitrophenyl7-thiolophosphoric acid ester To emphasize the effect against soil-dwelling, seed-borne and sprout-parasitic fungi. The substances according to the invention are particularly useful in combating rice diseases proven. The ore in appropriate substances thus represent a real one Enrichment of technology.

If O- / 2-nitro-2-methyl-3-chloro-propyl7-S-phenyl thiophosphoric acid ester chloride and methyl mercaptan are used as starting materials, the course of the reaction can be represented by the following equation: , 2 "S t acid-binding iiO2 CtL-C112-C 'CH20P \ + CHs H zuCl-CHrC-CH2-0- CH3 C1-HC1 C YCH3 3 The starting materials to be used are clearly defined by the formulas (II) and (III). R preferably represents methyl and ethyl, R 'represents straight or branched alkyl having 1 to 4 carbon atoms and R "preferably represents phenyl, which can optionally be substituted by chlorine, methyl and / or ethyl.

The O-alkyl-S-phenyl-thiophosphoric acid ester chlorides of the formula (II) required as starting materials can be prepared as follows: Starting from nitroalkanes, formaldehyde leads to dihydroxy compounds which close a ring with phosphorus trichloride, to 2-chloro-5-nitro- 5-alkyl-I, 3,2-phosphorinanes, which then react with arylsulenic acid chlorides to form the S-phenyl-O-alkyl-thiophosphoric acid ester chlorides of constitution (II): As examples of the S-phenyl-0-alkyl-thiophosphoric acid ester chlorides to be reacted according to the process, the following may be mentioned in detail: S-phenyl-, S-Z2-chlorophenyl7-, salts chlorophenyl7-, S- [2-methylphenyl] -, S-thylphenyl7-, S- [4-methylphenyl] -, S- [4-ethylphenyl] -, S-Z3-methylphenyl7-, S- [3-ethylphenyl] -O- [2'-nitro-2'-methyl-3'-chloro propyl] thiolophosphoric acid ester chloride.

As examples of the mercaptans to be converted according to the process Formula (III) may be mentioned in detail: methyl, ethyl, h-propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl and tert-butyl mercaptan. The connections and their production are well known.

The manufacturing process is preferred with the use of more suitable ones Solvent or diluent carried out. As such, practically all inert ones come organic solvents in question. These include above all aliphatic and aromatic, optionally chlorinated hydrocarbons, such as benzene, toluene, gasoline, methylene chloride, Chloroform, Carbon tetrachloride, chlorobenzene, ethers such as diethyl and dibutyl ethers, dioxane, also ketones, for example acetone, methyl ethyl, methyl isopropyl and methyl isobutyl ketone, also nitriles, such as aceto- and propionitrile.

All customary acid binders can be used as acid acceptors Find. Alkali carbonates and alcoholates, such as sodium and potassium carbonate, methylate or ethylate, also aliphatic, aromatic or heterocyclic amines, for example triethylamine, trimethylamine, dimethylaniline, Dimethylbenzylamine and pyridine.

The reaction temperature can vary within a relatively wide range will. In general, one works between 0 and 1200C, preferably at 20 to 600C.

The reaction is generally carried out under normal pressure.

The mercaptan component is used to carry out the process mostly in excess. The reaction is preferred in the presence of one of the above named solvent, as well as in the presence of ekies acid acceptor at the specified Temperatures made after several hours of stirring - optionally with heating - The reaction mixture is worked up as usual.

The substances according to the invention usually fall in the form of colorless to weakly yellow colored oils that cannot be distilled without decomposition, but through prolonged heating under reduced pressure to moderately elevated temperatures from the The last volatile components are freed and cleaned in this way. To their characterization mainly the refractive index is used.

The active ingredients according to the invention are highly fungitoxic Effect on. They damage crops in the areas necessary for combating fungi Concentrations do not and have a low toxicity to warm blooded animals. For these reasons they are suitable for use as pesticides for combating fungi. Fungitoxic agents in crop protection are used to control Archimycetes, Phycomycetes, Ascomycetes, Basidiomycetes and Fungi imperfecti.

The active ingredients according to the invention have a very broad spectrum of activity and can be used against parasitic fungi that affect parts of plants above ground infested or attacking the plants from the BQden as well as seed-borne pathogens.

The active ingredients according to the invention have proven themselves especially in combating Proven from rice diseases. So they showed an excellent effect against the fungi Piricularia oryzae.

Surprisingly, the active ingredients not only show a protective Effect, but also a curative and systemic effect.

They are also highly effective and of particular practical importance the - active ingredients when used as seed dressings or soil treatment agents phytopathogenic fungi are used that adhere to the seeds or occur in the soil and on cultivated plants seedling diseases, root rot, tracheomycoses, stem, Cause stem, leaf, flower, fruit or seed diseases, such as Tilletia caries, Helminthosporium gramineum, Fusarium nivale, Fusarium culmorum, Rhizoctonia solani, Phialophora cinerescens, Verticillium alboatrum, Fusarium dianthi, Fusarium cubense, Fusarium oxysporum, Fusarium solani, Sclerotinia sclerotiorum, Thielaviopsis basicola and Phytophthora cactorum.

The active ingredients according to the invention have also proven to be effective, for example against Cochliobolus myiabeanus, Mycosphaerella musicola, Cercospora personata, Botrytis cinerea and Alternaria species.

Depending on their intended use, the new active ingredients can be converted into the usual ones Formulations such as solutions, emulsions, suspensions, powders, Pastes and granulates. These are prepared in a known manner, for example by mixing the active ingredients with extenders, i.e. liquid solvents and / or solid Carriers, optionally with the use of surface-active agents, that is Emulsifying and / or dispersing agents, e.g. in the case of using water as an extender, optionally organic solvents as auxiliary solvents can be used. The main liquid solvents that can be used are: Aromatics (e.g.

Xylene, benzene), chlorinated aromatics (e.g. chlorobenzenes), paraffins (e.g. petroleum fractions), alcohols (e.g. methanol, butanol), strongly polar solvents such as dimethylformamide and dimethyl sulfoxide and water; as solid carriers: natural rock flour (e.g. kaolins, clays, talc, chalk) and synthetic Rock flour (e.g. highly dispersed silica, silicates); as emulsifier: non-ionic and anionic emulsifiers such as polyoxyethylene fatty acid esters, polyoxyethylene fatty alcohol ethers, (e.g. Alkylaryl polyglycol ethers, alkyl sulfonates and aryl sulfonates); as a dispersant: e.g. lignin, sulphite waste liquors and methyl cellulose.

The active compounds according to the invention can be mixed in the formulations with other known active ingredients.

The formulations generally contain between 0.1 and 95 percent by weight Active ingredient, preferably between 0.5 and 90%.

The active ingredients can be used as such, in the form of their formulations or in the use forms prepared therefrom, such as ready-to-use solutions, emulsifiable Concentrates, emulsions, suspensions, wettable powders, pastes, soluble powders, dusts and granules can be used. It is used in the usual way, e.g. by spraying, atomizing, atomizing, dusting, scattering, smoking, gasifying, Pouring, pickling or encrusting.

The active ingredient concentrations in the ready-to-use preparations can be varied in larger areas.

In general they are between 0.0001 and 10%, preferably between 0.01 and 1%.

In the treatment of seeds, amounts of active ingredient of 0.1 to 10 g per kg of seed, preferably 0.5 to 5 g, are required. For soil treatment Active ingredient quantities of 1 - 500 g per cubic meter of soil, preferably 10 - 200 g, are required.

The active ingredients can also be used with good success in the ultra-low-volume process (ULV) should be used where possible, formulations up to 95 ° f0 or even to bring out the 100% active ingredient alone. The compounds also have a insecticidal effect0 The excellent fungitoxic effectiveness of the products of the process, as well as their unexpected superiority compared to known ones Active ingredients with the same direction of action go from the following application examples emerge: Example A: Piricularia and Pellicularia test solvents: 1.9 parts by weight of dimethylformamide dispersant: 0.1 part by weight of alkyl aryl polyglycol ether Water: 98 parts by weight. Mix the one for the desired concentration of active ingredient amount of active substance required in the spray liquid with the.

given amount of solvent and dispersant and diluted the concentrate with the specified amount of water.

The spray liquid is sprayed 2 X 30 for about 2 to 4 weeks old rice plants to dripping wet. The plants remain until they dry in a greenhouse at temperatures of 22 to 24OC and a relative humidity of about 70%. Then one part of the plants is coated with an aqueous suspension from 100,000 to 200,000 spores / ml of Piricularia oryzae inoculated and in one Room set up at 24 to 260C and 100, relative humidity.

The other part of the plants is grown on malt agar with one Culture of Pellicularia sasakii infected and at 28 to 300C and 100% relative Humidity set up.

5 to 8 days after the inoculation, the infestation is all at the time the inoculation with Piricularia oryzae leaves as a percentage of the untreated, but also determined inoculated control plants. For those with Pellicularia sasakii infected plants, the infestation will occur on the leaf sheaths after the same time also determined in relation to the untreated but infected control.

0% means no infestation, 100% means that the infestation precisely is as high as in the control plants.

Active ingredients, active ingredient concentrations and results are based on the following Table.

Table Piricularia test (a) and Pellicularia test (b) Infestation in 56 of the infestation of the untreated control in the case of an active ingredient Active ingredient concentration (in 56) of away 0.05 0.025 0.05 0.025 0 (C2H50) 2-b'-S - N02 pr. 0 75 cur. 100 (known) N02 ° C1-CH2-C-CH2-0-P / \ J pr. 0 0 25 CH3 \ S-C2H5 for. 0 25 N, 02 O pr. 0 0 0 27 Cl-CH2-C-CH2-0-P \ O pr. 0 0 0 27 L1 L pr O 0 N'02 / 0 (L - pr. 0 0 6H SCH3 cur. 50 3 N02 ° oS- O pr. rL tr - pr. 0 0 CH3 \ 3H7 cur. 25th N02 O Cl-CH2-C-CH2-0-P w pr. o 0 CH3 SC2H5 cur. 75 C, H3 / S- t pr. 0 8 C1-CH2IC-CH2-O-cur. 75 Production examples: Example 1: 102 g (0.27 mol) of S- [2'-chlorophenyl] -O- [2-nitro-2-methyl-3-chloropropyl7-thiophosphoric acid ester chloride and 19 g (0.4 mol) of methyl mercaptan in 500 ml of benzene are mixed with 33 g (0.33 mol) of triethylamine are added at 20 to 25 ° C. The mixture is then stirred for 2 hours at 50 to 60 ° C., washed once with 1 liter soda solution and twice with 1 liter of water. The reaction solution is dried and the solvent is distilled off. 86.7 g of the desired S-ethyl-S- / Z'-chlorophenyl7-0- / Z-nitro-2-methyl-3-chloropropyl7-dithiophosphoric acid ester with a refractive index nD = 1.5643 are obtained. The yield is 79 56 of theory.

The following were produced in the same way: At- physical. game property No constitution th yield 2 Cl-CH2-C-CH -0 pw S t n25 CH3 3H7n NO9 0 5 1 S nD25 = 1.5705 92.7 56 1 L -Of: k / 25 => 5705 92.7 CH 3 At- physical. game property No constitution th yield NO, O n2 = t 2H 0 Pz O nD5 = 68.5 68.5.% CH3 5 N, 02 O n25 - 1 5577 83 56 Cl-CH2-C, -CH2-0-PD C2H5 SC2H5 6 N, 0 0 '- nD 1 76 6 Cl-CH2-C-CH2-0-Pz S 5 and 5 = 5630 56 CH3 SC2H5 Pre-products: The pre-products can be manufactured as follows: 60 g of paraformaldehyde and 89 g (1 mol) of nitropropane in 500 ml of ethyl acetate are boiled with 2 ml of potassium hydroxide solution (approx. 30%).

The solvent is distilled off in vacuo and the organic residue is distilled off. 131 g (88 56 of theory) of the desired product with a refractive index nD = 19 4654 remain behind. The liquid slowly crystallizes.

75 g (0.5 mol) of the product obtained in 400 ml of methylene chloride are mixed with 75 g of phosphorus trichloride at 20 to 30 ° C., the mixture is stirred overnight and the solvent is distilled off. The organic phase is distilled and solidified. 104 g (97 56 of theory) of the desired product with a melting point of 50 to 60 ° C. are obtained.

86 g (0.4 mol) of 2-chloro-5-nitro-5-ethyl-1fl3,2-phosphorinane in 300 cc of methylene chloride are mixed with 58 g of phenylsulfenic acid chloride at 15 to 200C offset. The mixture is stirred for a further 2 hours and the solvent is evaporated off in vacuo and the residue is distilled off. The precipitated disulfide is then suctioned off. 105 g (73.56 of theory) of S-phenyl-O- / Z-nitro-2-ethyl-3-chloropropyl7-thiophosphoric acid ester chloride remain behind with the refractive index nD26 = 1.5494.

Claims (6)

Patent claims: J1) S-phenyl-S-alkyl-0-alkyl-dithiophosphoric acid ester of <. formula in which R and R 'stand for alkyl with up to 6 carbon atoms and stands for phenyl, which can optionally be substituted one or more times by halogen or alkyl with up to 4 carbon atoms. 2) Process for the preparation of S-phenyl-S-alkyl-0-alkyldithiophosphoric acid esters, characterized in that S-phenyl-O-alkyl-thiophosphoric acid ester chlorides of the formula in which R and R "have the meaning given in claim 1, with mercaptans of the formula R'SH in which R 'has the meaning given in claim 1, in the form of their salts or in the presence of acid binders. 3) Fungicidal agent, characterized by a content of S-phenyl-S-alkyl-0-alkyl-dithiophosphoric acid esters according to claim 1 4) method for combating fungi, characterized in that that one S-phenyl-S-alkyl-0-alkyl-dithiophosphoric acid ester according to claim 1 on fungi or let their living space act. 5) Use of S-phenyl-S-alkyl-0-alkyl-dithiophosphoric acid esters according to claim 1 for combating fungi. 6) Process for the production of fungicidal agents, characterized in that that S-phenyl-S-alkyl-0-alkyl-dithiophosphoric acid ester according to claim 1 with extenders and / or surfactants mixed together.