IL42564A - O-(substituted alkoxy)phenyl carbamates ther preparation and pesticidal compositions containing them - Google Patents

Description

onaan ,o*tnn ο»©οκ:ηρ »aa(n»ma OpiKp t -O Hovel 0-( substituted alkoxy)phenyl carbamates, their preparation and pestioid l oompocitions containing them BADISCHE .miLI - & SODA-FABBIK AKTIENGBSBLLSCHAPT 0. 40740 f The present invention relates to new and valuable carbamates; pesticides containing these compounds as active ingredients; and a process for controlling pests with these compounds.; It is known to use 1-naphthyl-N-methylcarbamate and o-iso- j propoxyphenyl-N-methylcarbamate as insecticides. However, their > action is poor.

We have now found that carbamates of the formula 1 2 where R denotes hydrogen or methyl, R denotes hydrogen or lover alkyl (such as methyl or ethyl), R denotes: C^-C^ alkyl; alkyl of a maximum of 3 carbon atoms substituted by halogen, preferably chlorine, bromine and iodine; alkyl of a maximum of 3 carbon atoms substituted by methoxy or ethoxy 4 and R denotes methyl, ethyl, isopropyl, chloroethyl or acetyl, have excellent acaricidal and insecticidal properties and are also suitable for combatting ectoparasites and endoparasites in animals.

They have a very good action not only on biting and sucking insects but also on mites and ticks. Phytotoxicity is low. he action sets in rapidly and lasts for a long tins. Fbrthis reason the compounds of the - la- O.Z. 29,241 M invention may be successfully used in the plant protectic™ sector for combatting injurious sucking and biting insects and Diptera, and for combatting Acarina in the plant protection and veterinary sectors. Of special importance in this--connection is the excellent action of the compounds on strains of mites which are resistant to phosphoric esters.

The main members of the group of sucking insects are aphids such as the green peach aphid (M zus persicae) and the bean aphid (Doralis fabae); scales, such as Aspidiotus hederea, Lecanium hesperidum, Pseudococcus maritimus; Thysanoptera, such as Hercinothrips femoralis and bugs, such as Piesma quadrata and the bed bug (Cimex lectularius) .

The main members of the group of biting insects are caterpillars, such as Plutella maculipennis and Lymantria dispar; beetles, such as the granary weevil (Sitophilus granarius), Colorado potato beetle ' (Leptinotarsa Decembineata) , and also types living in the soil, e.g., wireworms (Agriotes sp. ) and cockchafer (Melolontha melolontha); bugs, such as the croton bug (Blattela germanica); Orthoptera, such as the house-cricket (Gryllus domesticus); termites, such as Reticulitermes; and Hymenoptera, such as ants.

The Diptera include in particular the flies, e.g. fruit fly (Drosophila melanogaster); Mediterranean fruit fly (Cera-titis capitata); housefly (Musca domestica); gnats such as the yellow fever mosquito (Aedes aegypti) and Culex pipilus; bluebottles, such as Lucilia sericata; and blowflies (Chrysomya chloropyga) .

Of the mites, the following are of particular importance: Tetranychidae, such as the red spider mite (Tetranychus urticae) and Paratetranychus pilosus; gall' mites, such as β the currant mite (Eriophyes ribis) and Tarsonemidae , such as Tarsonemus pallidus; ticks, e.g. Boophilus microplus, and itch mites.

Application of the compounds is by conventional methods, e.g. spraying, atomizing, fuming, broadcasting, etc.

Phenyl carbamates of a structure similar to those of the present invention, in which the phenyl ring is substituted with a group R - X - (GH„) - 0 - 2 n where R is C^-C^ alkyl or C^-C^ halo-substituted alkyl, n is 1 or 2 and X is oxygen or sulphur, are known s from Israel Patent Specification No. 26025.

These compounds have insecticidal and acaricidal activity.

It has surprisingly been found that the compounds of the present invention have a much better activity against flies and cockroaches than the most closely related known compounds bearing the above-mentioned substituent.

The new carbamates may be prepared for instance by reacting where R , R^ and R have the above meanings, with methyl iso-cyanate, N-methylcarbamyl chloride or N,N-dimethylcarbamyl chloride. The phenol may also be converted into the new carbamates via the chloroformate by reaction with methylamine or dimethylamine . Phenols of the formula II may be prepared in accordance with conventional methods for the synthesis of acetals or ketals, for instance pyrocatechol may be reacted in a molar ratio of 1:1 with a suitably substituted oL-halo ether or vinyl ether; trans-acetalization may sometimes be useful, in which case the alcohol component of the acetal or ketal used should contain a low number of carbon stoms, expediently 1 to 4 in order for it to be easily removed by distillation from the reaction vessel; the equilibrium is shifted in the direction of the desired products of the formula II.

Further, carbamates of the formula III l5 N - 3a - O.Z. 29,2 1 where R has the above meanings, may be reacted to the ne A carbamates with d--halo ethers of the formula IV R2 hal-C-R^ 1 0-R where R 2, "5 and R4 have the above meanings and hal denotes chloro or bromo, with the aid of suitable bases (e.g. alkali metal hydroxides, tertiary amines) in indifferent solvents (e.g. tetrahydrofuran, dioxane, benzene, toluene, xylene, di-ethylene glycol dimethyl ether). The JL-halo ethers required for this route are prepared by conventional methods.

Carbamates of the formula III may, by acid catalysis, also be reacted to the new carbamates with acetals or ketals of the formula V R^ where R , R and R have the above meanings, by partial trans-acetalization or trans-ketalization, one alcohol of the for- 4 mula R OH being distilled off. 4 The number of carbon atoms in the alcohols R OH should be advantageously such that the alcohols may be easily removed from the reaction mixture by distillation, thus shifting the reaction equilibrium in the desired direction.

Appropriately substituted vinyl ethers are also suitable for the production of the new carbamates; carbamates of the formula III are reacted in conventional manner by acid catalysis with the vinyl ethers which in turn have been prepared by known - 4 - O.Z. 29,241 methods. The route selected depends on the availability o"the alkylating agent. The examples below demonstrate the various production methods.

EXAMPLE 1 a) Over a period of 1 hour and at 20° to 30°C, 129 parts (by weight) of 1 , 2-dichloroethyl methyl ether is dripped into a solution of 1 10 parts of pyrocatechol and 101 parts of triethylamine in 500 parts of tetrahydrofuran. The mixture is then stirred for approx. 6 hours. The amine hydrochloride is subsequently filtered off, the solvent distilled off, and the resi-due purified with chloroform/water. After the chloroform has been removed by distillation there is obtained 196 parts of o- ( dl-methoxy-6-chloro)-ethoxyphenol; : I.5215 .

At about 25°C, a few drops of triethylamine and subsequently 6.3 parts of methyl isocyanate are added to a solution of 25 parts of tetrahydrofuran in 20. 2 parts of o- (^L-methoxy-fi-chloro)-ethoxyphenol . The end product is formed in a weakly exothermic reaction. After stirring for 2 hours at 50°C the volatiles are distilled off at 0° to 50°C under a water jet vacuum. After recrystallization from ether there is obtained 20.5 parts of o- (ck-methoxy-fi-chloro )-ethoxyphehyl-N-methylcarbamate as colorless crystals; m.p. : 70°C. b) A mixture of 8.3 parts of pyrocatechol mono-N-methylcarba-mate, - 1 parts of triethylamine and 7. 1 parts of 1 , 2-dichloroethyl methyl ether in 7 parts of toluene is heated for about 5 hours at 100° to 1 10°C. After the volatiles have been distilled off in vacuo the residue is taken up in chloroform, filtered and washed with 0.5$ (by weight) aqueous sodium bicarbonate - 5 - O.Z. 29,241 solution. The residue remaining after the chloroform has ien distilled off may be recrystallized from a mixture of ether and ligroin. Yield: 9 · 7 parts of o-(e|w-methoxy-S-chloro)-ethoxy-phenyl-N-methylcarbamate ; m.p.: 69° to 71°c « EXAMPLE 2 From 10.8 parts of pyrocatechol-N, N-dimethylcarbamate (m.p. 1 19° to 121°C), 6. 1 parts of triethylamine and 8.4 parts of 1, 2-dichloroethyl methyl ether in 75 parts of toluene there is obtained, after a reaction period of about 5 hours and in a manner similar to that described in Example 1 , 13- 7 parts of o-(<^, -methoxy-fi~chloro)-ethoxyphenyl-N, N-dimethylcarbamate as a pale, yellowish oil; : 1 .5170.

EXAMPLE J At room temperature, about 0. 5 part of boron trifluoride etherate is added to a solution of 8. 3 parts of pyrocatechol mono-N-methylcarbamate and 5 · 9 parts of 2-chloroethyl vinyl ether in 25 parts of tetrahydrofuran. The mixture is then stirred for 1 hour at room temperature and for about j5 hours at the boiling temperature. After the volatiles have been distilled off there is obtained 12.4 parts of o- (JL - 2-chloroethoxy) - 25 ethoxyphenyl-N-methyl carbamate as an oil; n ^ : 1 .521 1 .

EXAMPLE 4 6 - 7 parts of pyrocatechol mono-N-methylcarbamate in 75 parts of toluene is placed in a flask. 2 drops of concentrated sulfuric acid are then added and 6. 1 parts of 3-methoxypropion-aldehyde dimethyl acetal is dripped in. The contents of the flask are then stirred for about 2 hours at 90° to 100°C, methanol distilling off. - 6 - O.Z. 29, 241 After cooling, 1 to 2 parts of sodium bicarbonate is.Added to the mixture , which is then washed with water. After concentration of the organic phase there is obtained 9 parts of o-( <_L » < -dimethoxy )-n-propoxyphenyl-N-methylcarbamate as a pale yellow oil; n2^ : 1 .5184.

EXAMPLE 5 a) 1 10 parts by weight of pyrocatechol is suspended in 500 parts by weight of toluene. There is then added 1/2 ml of concentrated hydrochloric acid. While stirring and at an internal temperature of 10° to 30°C, 58 parts by weight of methyl vinyl ether is added to the mixture with condensation. The whole is then heated for j50 minutes at 60°C. The mixture is subsequently cooled and made just alkaline by adding 2N NaOH. It is then washed with 50 ml of water and the organic solution is separated and dried over Na^SO^. The solvent is removed and the residue distilled under an oil pump vacuum. There is obtained 120 parts by weight of a colorless oil; b.p. ( 1-2 mm); 72° to 75°C The reaction product is stabilized with 2 drops of pyridine, b) While cooling, 101 parts by weight of triethylamine is added to a suspension of 1 10 parts by weight of pyrocatechol in 1 , 000 parts by weight of toluene. 95 parts by weight of ^l-chloro-ethyl methyl ether is then dripped in while stirring thorougly. The internal temperature is kept at 30° to 0°C by cooling. The mixture is stirred for 3 hours at 50°C and then cooled. The hydrochloride which has formed is suction filtered and the filtrate washed with 100 ml of water. The organic phase is dried over a2S0^ and worked up as described in Example 1 a.

Yield: 112 parts by weight of o- ( 1-me thoxy ) -e thoxyphe: 1.

EXAMPLE 6 Other vinyl ethers or ct-halo ethers are reacted with pyrocatechol employing the method described in Example 1 a and b. Higher vinyl ethers are liquid and are simply dripped into the pyrocatechol suspension. The following table lists the phenol derivatives obtained.

No. R3 R2 R* b.p. Acetalphenol (°C) 6 CH^ H CH, ( 1-2 mm) : 72-75 3 7 CH, H ( 1 mm) : 78-81 3 C2H5 8 CH, H ( 1 mm) : 8 -90 3 3 1 9 H CH, ( 1 *5 mm) : IO5-II3 C2H5 3 10 C2H5 H C2H5 (0. 1 mm) : 83-90 11 n-C,H_ H CH, ( 0. 2 mm) : 95- 108 3 7 3 12 i^H? H CH^ (0.5 mm) : 88-90 3- 1 13 n-C H9 H CH, 3 ( 0.15 mm) : 97-108 14 n-C H9 H C2H5 15 i-C H9 H CH, 3 ( 0.3 mm) : 98-IO5 16 CH, CH^ CH, 3 3 ( 0. 3 mm) : 90- 100 17 CH, CH, 3 C2H5 18 CaH5 CH^ CH^ EXAMPLE 19 o- ( 1-methoxy- ) -ethoxy heny 1 -N-methyl carbamate 12 parts by weight of methyl isocyanate is added in a single portion to a solution of 3^ parts by weight of o- ( 1-methoxy )-ethoxyphenol in 100 parts by weight of toluene. 2 drops of triethylamine are then added. After having been left standing - 8 - O.Z. 29,241 overnight, the mixture is concentrated. 100 parts by weig of a mixture consisting of equal parts of toluene and ligroin is added to the oily residue. Upon cooling 33 parts by weight of colorless crystals precipitate out. After repeated crystallization the crystals melt at 97° to 99°C.

EXAMPLE 20 o- ( 1-ethoxy)-ethoxyphenyl-N-methylcarbamate 33·^ parts by weight of pyrocatechol mono N-methylcarba-mate is suspended in 100 parts by weight of toluene. After the addition of drops of concentrated hydrochloric acid 15 parts by weight of vinylethyl ether is dripped in over a period of 10 minutes. The mixture is then stirred for 1 hour at 80°C and then cooled. It is washed with 50 parts by weight of 3$ NaHCO^ solution and dried over NagSO^. After removal of the solvent a colorless oil remains which is taken up in 100 parts by weight of a mixture consisting of equal parts of toluene and ligroin. 31 parts by weight of carbamate crystallize out in the freezer. After repeated recrystallization the melting point is 62° to 63°C.

EXAMPLE 21 The substances listed below were prepared by the methods of Examples 3 and 4: - 9 - 25 R1 . R3 K2 m. . n p H CH^. H CH, 97-99 H. CH, H 3 C2¾ 62-63 H CH^ H i-C^H7 H C2H5 H 88-90 H H C2H5 C2H5 2- H H CH^ 48-49 H H CH,: 7^-76 57 H H CH, 9 46-47 H n-C H9 H C2H5 H i~C¼H9 H CH, l.5020 H n-C H9 H CH, .5 H CH, CH, CH, 80-82 H -CH, CH, 2H5 H CH, CH^ C2H5 CH^ CH, H CH, .5 Examples of other new carbamates are - 10 - R1 R2 R? R* ¾p°C (n H H CH2C1 2H5 (1:5125) H - H CH2C1 COCH, (1:5119) CH, H CH2C1 C2H5 (1:5205) .3 ■CH,. H CHgBr CH, (1: 510) ? H H CHgBr CH, 70-72 H H CH2I , CH, (1:5465) CH, H CH2I CH^ H H CH2"CH2C1 CH, 65-66 CH^ H CH2-CH2C1 CH^ H H CHCl-CH, CH, · H H CHBrCH, CH^ H H CH2-CH2Br CH, H H CHo0CH, CH^ CH, H CH2-0CH5 CH, H H CH(OCH5)-CH^ CH, .2 H CH, CH2C1 CH, IO6-IO8 j CH^ CH, CH2C1 CH^ H CH^ CH2Br CH, The agents according to the invention may be used as solutions, emulsions, suspensions or dusts. The form of application depends entirely on the purpose for which the agen are being used; in any case it should ensure a fine distribut - 11 - O.Z. 29,2 1 A of the active ingredient.

For the preparation of solutions to be sprayed direct, the solution in water is suitable. However, hydrocarbons havin boiling points higher than 150°C, e.g. tetrahydronaphthalene or alkylated naphthalenes, or organic liquids having boiling points higher than 150°C and having one or more than one functional group, e.g. the keto group, the other group, the ester group or the amide group, this group or these groups being attached as substituen (s) to a hydrocarbon chain or being a component of a heterocyclic ring, may also be used as spray liquids .

Aqueous formulations may be prepared from emulsion concentrates, pastes or wettable powders by adding water. To prepare emulsions the ingredients as such or dissolved in a solvent may be homogenized in water or organic solvents by means of wetting or dispersing agents, e.g., polyethylene oxide adducts. Concentrates which are suitable for dilution with water may be prepared from active ingredient, emulsifying or dispersing agent and possibly solvent.

Dusts or granules may be prepared by mixing or grinding the active ingredients with a solid carrier, e.g., kieselguhr, talc, clay or fertilizers.

EXAMPLE 90 parts by weight of the compound of Example 1 is mixed with 10 parts by weight of N-methyl-dL-pyrrolidone . A mixture is obtained which is suitable for application in the form of very fine drops. - 12 - O.Z. 29,241 EXAMPLE 5 20 parts by weight of the compound of Example 2 is dissolved in a mixture consisting of 80 parts by weight of xylene, 10 parts by weight of the adduct of 8 to 10 moles of ethylene oxide to 1 mole of oleic acid-N-monoethanolamide, parts by weight of the calcium salt of dodecylbenzenesulfonic acid, and parts by weight of the adduct of 40 moles of ethylene oxide to 1 mole of castor oil. By pouring the solution into 100,000 parts by weight of water and uniformly distributing it therein, an aqueous dispersion is obtained containing 0.02$ by weight of the active ingredient.

EXAMPLE 6 20 parts by weight of the compound of Example 3 is dissolved in a mixture consisting of 40 parts by weight of cyclohexanone, 30 parts by weight of isobutanol, 20 parts by weight of the adduct of 7 moles of ethylene oxide to 1 mole of isooctylphenol, and 10 parts by weight of the adduct of 40 moles of ethylene oxide to 1 mole of castor oil. By pouring the solution into 100,000 parts by weight of water and uniformly distributing it therein, an aqueous dispersion is obtained containing 0.02$ by weight of the active ingredient.

EXAMPLE 20 parts by weight of the compound of Example 1 is dissolved in a mixture consisting of 25 parts by weight of cyclohexanol, 65 parts by weight of a mineral oil fraction having a boiling point between 210° and 280°C, and 10 parts by weight of the adduct of 40 moles of ethylene oxide to 1 mole of castor oil. By pouring the solution into 100,000 parts by weight of water and uniformly distributing it therein, an aqueous dispersion O.Z. 29,241 m is obtained containing 0.02 by weight of the active ingredient .

EXAMPLE 38 20 parts by weight of the compound of Example 1 is well mixed with 3 parts by weight of the sodium salt of diisobutyl-naphthalene-οί. -sulfonic acid, 17 parts by weight of the sodium salt of a ligninsulfonic acid obtained from a sulfite waste liquor, and 60 parts by weight of powdered silica gel, and triturated in a hammer mill. By uniformly distributing the mixture in 20, 000 parts by weight of water, a spray liquid is obtained containing 0.1$ by weight of the active ingredient.

EXAMPLE 9 3 parts by weight of the compound of Example 2 is intimately mixed with 97 parts by weight of particulate kaolin. A dust is obtained containing 3$ by weight of the active ingredient.

EXAMPLE 40 0 parts by weight of the compound of Example 3, ..is Intimately mixed with a mixture consisting of 92 parts by weight of powdered silica gel and 8 parts by wegit of paraffin oil which has been sprayed onto the surface of this silica gel. A formulation of the active ingredient is obtained having good adherence.

For the following experiments the following active ingredients were used: (according to the invention) O.Z. 29,241 (according to the invention) comparative agent - 15 - O.Z. 29,241 omparative agent EXAMPLE 1 1 mm^ of an acetonic solution of the active ingredients is applied to the ventral abdomen of houseflies (Musca domestica) under slight C02 narcosis.

The Dr-n is calculated from the mortality rate of the flies 50 after 4 hours.

Active ingredient I 10.0 T/fly ineffective II 10.0 T/fly ineffective EXAMPLE 42 Adult oriental cockroaches (Blatta orientalis) are placed in 1 liter glass beakers whose inner surfaces have been treated with acetonic solutions of the active ingredients. The action is determined after 48 hours. ^ O.Z. 29,241 Active ingredient Amount of active Mortality ingredient in mg/beaker I 0. 2 100$ II 0.5 100 1 0. 05 100$ 5 · 0. 02 100$ EXAMPLE 3 Contact action and effect of ingested food on caterpillars of the cabbage moth (Plutella maculipennis ) . Young cabbage leaves are dipped for j5 seconds into aqueous emulsions of the active ingredients. After they have dried they are put into Petri dishes and caterpillars of the cabbage moth are placed on them.

Active ingredient Amount of ingredient Mortality in aqueous emulsion in $ by weight I 0. 1 100$ II 0. 1 ineffective III 0. 1 ineffective 1 0. 05 100$ 6 0. 02 100$ - 17 -

Claims (2)

1. 42564/35 C L A I M S : i 1. A carbamate of the formula -where R denotes hydrogen or methyl, R denotes hydrogen or lover alkyl, denotes Cj-C^ alkyl, lower alkyl of maximum 3 carbon atoms substituted by halogen, methoxy or ethoxy, and R4 denotes methyl, ethyl, isoprop l, chloroethyl or acetyl.

2. The preparation of a carbamate as claimed in claim 1 wherein a phenol of the formula 2 ii where R , R^ and R have the above meanings, is reacted with either a) methyl isocyanate, or b) N-methylcarbamyl chloride or Ν,Ν-dimethylcarbamyl chloride, or c) first phosgene to the chloroformate, and then methylamine or dimethylamine . The preparation of a carbamate as claimed in claim 1 wherein a carbamate of the - 18 - 2564 3- where R has the above meanings, is reacted with either a) an cL-halo ether of the formula b) an acetal or ketal of the formula where R , R^ and R have the above meanings, in the molar k ratio 1:1, the molar amount of R OH being eliminated, or c) a substituted vinyl ether. . o- ( 5. o- (o -me thox )-e thoxyphenyl-N-methylcarbamate . 6. A pesticide comprising a solid or liquid carrier and a carbamate of the formula where R denotes hydrogen or methyl, R denotes hydrogen or lower alkyl, ^ denotes C^-C^ alkyl, lower alkyl of maximum up to 3 carbon atoms substituted by halogen, methoxy or ethoxy, and denotes raethyl, ethyl, isopropyl, chloroethyl or acetyl. 7. A process for combatting pests wherein the pests are treated with a carbamate of the formula 42564/3 where R denotes hydrogen or methyl, R denotes hydrogen or lower alkyl, R denotes G^-C^ alkyl, lower alkyl of maximum 3 carbon atoms substituted by halogen, methoxy or ethoxy, and R denotes methyl, ethyl, isopropyl, chloroethyl or acetyl. - 20 -