IL35203A - O-methyl o-(2,2,2-trihaloethyl)o-(2',2'-dihalovinyl)-phosphates,their production and use as pesticides - Google Patents

Description

AGRIPAT. S.A.

The present invention concerns new O-methyl 0-(2,2,2,-trihaloethyl) -(2' ,2' -dihalovinyl) phosphoric acid esters, process for the production thereof as well as pesticidal compositions containing these phosphoric acid esters as active ingredients and method for the con rol of pests using the new active substances or compositions containing them.

The new O-methyl 0- (2 , 2 , 2- rihaloethyl) 0- (2 ', 2 ' -dihalovinyl) phosphoric acid esters correspond to the Formula I: 11 OCH^ .

CX.QUO — P ^1) . ^ 0CH= CY2 In this formula: X represents, fluorine or chlorine ,. and Y represents chlorine or bromine.

The new phosphoric acid esters of Formula I are produced according to the invention by converting trimethyl phosphite or 0 ,0-dimethyl phosphorous acid chloride in the presence of a base with a trihaloethano'l of the Formula II CX3CH2OH (II) into an 0 , 0-dimethyl 0- ( 2 , 2 , 2- trihaloethyl) phosphite and reacting this with chloral or bromal.

According to a modification of the process according to the invention, the phosphoric acid esters of Formula I are produced by reacting rime hy1 phosphite and phosphorus trichloride in the presence of an acid-binding agent with a trihaloethanol of the Formula II and chloral or bromal.

For the process according to the ivrvention, the following bases, for example, can be employed: tertiary amines such as trialkylamin.es, pyridine and pyridine bases, inorganic bases such as hydroxides, carbonates and cyanides of alkali metals. Moreover, alkali metal alkanolates can also be employed; such an alkanolate is also formed during the reaction after the addition of metallic alkali metal to the reaction mixture. Tertiary amines, in particular, as well as the inorganic bases listed may be employed to take up the hydrogen halide formed during the reaction of trimethyl phosphite and phosphorus trichloride with trihaloethanol.

The reactions according to the invention' may be performed in the presence or absence of a solvent or diluent. It is advisable to perform the reaction of trimethyl phosphite and phosphorus trichloride with trihaloethanol in the presence of a solvent which is inert towards the reaction componei^ts ; for this purpose aromatic hydrocarbons such as benzene, toluene, xylenes, and halogenated hydrocarbons such as chloroform, carbontetrachloride and" chlorobenzene have proved suitable. For the process according to the invention, it has been found expedient to employ the trimethyl phosphite in excess, the other reaction components, however, in molar equivalents. If 0,0-dimethyl phosphorous acid chloride is used in place of trimethyl phosphite, the reaction components are employed in equimolar amounts. Whereas by the interchange of ester radicals-- rimethyl; phosphite/ trihaloethanol-- the base can be employed in catalytic amounts; when the chloride is employed, equimolar amounts of the base are necessary. The reaction temperatures for interchange of ester radicals are in the range of 60-150°C, for the reaction of acid chloride/ trihaloethanol in the range of 0 - 50°, preferably 0 - 30°C. The methaitol which forms in the reaction is continuously removed by distillation from the reaction mixture, the hydrochloride base is removed by filtration. The intermediate product, 0,0- dimethyl 0- (2 , 2 , 2- trihaloethy1) phosphite, is then separated by distillation and purified. The reaction of this phosphite with chloral or bromal is performed at temperatures between 20 and 100°C, preferably at 50 to 80°C.

Depending on the reactivity of the individual reaction components, heating or cooling of the reaction mixture is required.

The modification of the process according to the invention is a "one-container" process. The 0,0-dimethyl 0- (trihaloethy1) phosphite resulting as intermediate can be reacted directly without further purification with chloral or bromal. The phosphoric acid esters of Formula I are then separated from the reaction mixture by distillation; they are obtained in high purity and very good yields. Trimethyl phosphite and phosphorus trichloride are employed in the reaction in a ratio of chloride to phosphite of 1:2 to 1:3, preferably 1:2; trihaloethanol, chloral or bromal and acid-binding agent (base) are employed in equimolar amounts relative to the phosphorus compounds; this corresponds to 3 - 4 mol of the individual reactants , preferably 3 mol. The reaction temperatures for. the reaction of phosphite and trihaloethanol are in the range of 0-50°, preferably 0-30°C; for the reaction of the inter- mediate with chloral or bromal they are from 20-100°, preferably 50-80°C.

From the literature a number of asymmetric 0,0-dialkyl 0- (2 , 2-dichlorovin.yl) phosphoric acid esters are known (cf. for example U . S . patents N os . 2,956,073 and 3,116,201; German patent No. 1,251,745). In general, they are produced by reaction of asymmetric trialkyl phosphorous acid esters (trialkyl phosphites) with chloral according to W. Perkow [cf. Naturwissenschaften 3.9, 353 ff (1952)]. 0-Alkyl 0- (2-chloroethyl) 0- (21 , 2 ' -dichlorovinyl) phosphoric acid esters are obtained according to British patent No. 806,638 from cyclic phosphorous acid esters with chloral. In German patent No. 1,178,420, the production of 0- (2 , 2-dichlorovinyl) phosphoric acid esters with one or two identical or differing halogenated tertiary alkyl radicals from corresponding 0- ( ter -haloalkyl) 0-alkyl phosphorous acid esters and chloral is described. The phosphorous acid esters are obtained in turn from PCl^ a d appropriate alcohols. Since on the one hand the chlorine atoms of the PCl^ cannot be exchanged in exact steps, and on the other hand a separation and isolation of asymmetric ti-ialkyl phosphites having lower alkyl radicals is very difficult, this method of producing the 0,0-di— methyl 0- ( 2 , 2 , 2- trihaloethy1) phosphite could not be used.

The replacement of a trichloroethyI group by the dichlorovinyl radical in tris- (2 , 2-dichloroethyl) phosphorous acid ester v/ith chloral led to 0 ,0-bis- (2 , 2 , 2- trichloroethyl)-l-hydroxy-2,2,2 trichloroethyl phosphonic acid [cf. B.A.Arbuzov, Dokl.Akad.

Nauk USSR 160, 99 ff (1965)].

. By the. process according to the invention, the not-previously-described 0,0-dimethyl 0- (2 , 2 , 2- trihaloethyj.) phosphorous acid esters necessary for the production of the new phosphoric acid ester of Formula I are obtained without difficulty. . They are isolated by distillation from the reaction mixture. In the modification of the process according to the invention, isolation is not necessary; chloral or bro al can be added directly to the reaction mixture after the separation of the precipitated salt.

The new 0-methyl 0- (2 , 2 , 2- trihaloethy1) 0- ( 2 2 ' -dichlorovinyl) phosphoric acid esters of Formula I have excellent insecticidal and acaricidal properties. Compared with known 0-alkyl 0- (21 , 2 ' -dichlorovinyl) phosphoric acid esters, for example the widely used 0 ,0-dimethyl-0-(2 ' ^'-dichlorovinyl pho phate (DDVP) , 0-methyl 0- ( 1-methyl- 1~ trichloro-methyl- ethyl) 0- (2 ', 2 ' -dichlorovinyl) phosphate and 0-methyl 0-(2-chloroethyl) 0- (2 2 ' -dichlorovinyl) phosphate (loc. cit) , the new active substances have a substantially more favorable toxicity for warm-blooded animals and a long-lasting insecticidal effect. They are thus suited, in particular for the protection of stored goods and for the control of insects in buildings, stables, etc.

In the following comparison table the toxicity for warmblooded animals is given.

Active substance: rat UL^Q PER OS O-methyl 0- (2 , 2 , 2- trichloroethyl) 0- (2 ', 2 * -di-bromovinyl) phosphate 1100-1700 mg/kg 0-methyl 0- ( 2 , 2 , 2- trifluoroethyl) 0- (2 ',2' -di-bromovinyl) phosphate 1400 mg/kg tri 0-methyl 0- ( 2 , 2 , 2-, :hloroethyl) 0-(2\2'--di-chlorovinyl) phosphate '' ~ 1000 mg/kg 0-methyl 0- (2 , 2 , 2-trifluoroethyl) 0-(2',2 dichlorovinyl) phosphate . 1100 mg/kg 0,0-dimethyl 0- (2 ' -21 -dichlorovinyl) phosphate (DDVP) , known insecticide - 80 mg/kg (see G. Schrader, "Die Entwicklung neuer , insektizider Phosphorsaureester , page 40-50, Tests with compounds of the Formula I on insects and arachnids showed that these active substances are good to very good stomach and coiitact poisons and also have a systemic insecticidal dffect..

It has thus been found that the active substances of the Formula I have, in. particular , an excellent, long-lasting effect against insects of the families Muscidae, Stomoxidae and Culicidae, e.g. against the polyvalent-resistant and normally sensitive house lies ( usca domestica) , stable flies (Stomoxys calcitrans) and mosquitoes (e.g. Aedes Aegypti, Culex fatigans , Anophenles Stephens!); against insects of the families Curculinidae , Bruchididae, Dermes- tidae, Tenebrionidae and Chrysomelidae , e.-g. granary weevil's' (Sitophilus granarius) , bean beetles (Bruchidus obtectus) , ' larder beetles (Der estes vulpinus) , mealworms (Teiebrio olitor) , Colorado potato beetles (Leptinotarsa . decemlineata) and their larval stages; against insects of the family Pyralididae, e.g. Mediterranean flour moths (Ephestia klihniella) ; of the family Blattidae, e.g. cock-roaches (Phyllodromia germanica , . Periplaneta americana, Blatta orientalis) ; of the family Aphididae, e.g. bean aphicls (Aphis fabae) ; of the family Pseudococcidae , e.g. citrus mealybugs (Planococcus citri) and of the family Locustidae, e.g. migratory locusts (Locusta inigratoria).

Tests on the said bean aphids and migratory locusts showed an excellent systemic effect.

In addition, the active substances of the Formula I according to the invention have a good action on the larval Ixodidae, Arachnidae and Argasidae. Ψ . In admixture with synergists and auxiliaries having a similar action such as dibutyl succinate, piperonyl butoxide, olive oil, and peanut oil, etc., the range of action of the said active substances can be broadened and in particular the insecticidal -and acaricidal action can be improved.

Likewise, the insecticidal action can be substantially broadened and adjusted to the prevailing conditions by the addition of other insecticides such as, for example, phosphoric, phosphonic , thio- and dithiophosphoric acid esters and amides , halogeiiated hydrocarbons and analogs of DDT-active substance as well as pyrethrines and synergists thereof, acaricidally active substances such as halogeno-benzilic acid. esters such as 4 ' , 41 -dichlorobenzilic acid esters and 41 ,41 -dibromobenzilic acid esters ,, insecticidal and acaricidal carbamates, for example oxime carbamates, aryl carbamates and carbamates of heterocyclic compounds which are enolizable.

Comparison Tests: The insecticidal activity of the new asymmetric phosphoric esters is illustrated by the following tests, using as comparison compound the 0 -methyl 0-- [ 1' , 1' -dimethyl-2 ' , 2 ' , 2 ' trichloroethyl] .-0-[2 , 2 -dichlorovinyl ] phosphate, disclosed in the German patent specification No. 1 178 420. 1. Effect _as .insecticidal. contact, p_ois_oji_ Petri dishes are coated with acetone solutions of the active substances so that they are covered with 0.15 g of active substance per square meter. After one hour the following test animals are placed in the dishes: 1) polyvalent-resistant house flies (Musca. domestica), 2) mosquitoes (Aedes aegypti) 3) granary weevils (Sitophilus granaria) 4) stable flies (Stomoxys calcitzrans).

The time is determined after which all (100%) of the animals are in dorsal position (see Table 1) : Table 1 Active Substance 1007o of the animals in dorsal po 1 mosqui- grana house flies • toes weevi O-me hyl 0- (2 , 2 , 2-trichloroethyl) · 0-(2' , 2 ' -dibromovinyl) phosphate 66 10 78 O-methyl 0- (2 , 2 , 2-trichloroethyl) 0-(2' , 2 ' -dichlorovinyl) phosphate 55 1 . 28 O-methyl 0- (2 , 2 , 2-trifluoroethyl) 0- (2 2 ' -dibromovinyl) phosphate 10 10 60 O-methyl 0- ( 2 , 2 , 2-trifluoroethyl) 0- (2 ' , 2 ' -dichlorovinyl) phosphate 20 23 30 O-methyl 0- [ 1* , 1' -dimethyl-2 ! ,2 \ 2 * -trichloroethyl] 0-[ 2, 2 -dichlorovinyl] phosphate (comparison) no activity 120 no act Longr lasting insecticidal effect Petri dishes which have been coated with 1.5 mg and 0.15 mg of active substance per square meter · . ■ -are allowed to stand for 6 days at 24° C. · .- _ ■ Then polyvalent-resistant house flies (Musca domestica) and mosquitoes (Aedes aegypti) are placed on the coatings. The time is determined after which all (1007o) of the animals are in dorsal position.

Table 2 Active Substance 100% of the animals in dor X minutes house flies 1.5 mg/m^ 0 of active substance o 0-methyl 0- (2 , 2 , 2-trichloroethyl) 0- (2 ' , 2 ' -dibromovinyl) phosphate 32 0-methyl 0- (2 , 2 , 2-trichloroethyl) 0-(2' , 2 ' -dichlorovinyi) phosphate 26 0-methyl 0- (2 , 2 , 2-trifluoroethyl) 0-(2' , 2 ' -dibromovinyl) phosphate 26 0-methyl 0- (2 , 2 , 2-trifluoroethyl) 0-(2' , 2 ' -dichlorovinyi) phosphate 0-methyl 0-[l' ,1' -dimethyl-2' ,2' ,2' -trichloroethyl ] 0-[ 2 , 2-dichlorovin i] phosphate (comparison) 300 Effect as insectic_id JL^_sj^ma_ch_-poison^ Filter paper is soaked with 207> honey-water and an acetone solution of 20 rag of active substance. After hours the moist filter paper, freed of acetone, is placed in with hungry polyvalent-resistant house flies for two hours. . After this the animals are fed water and sugar and kept at 22°C. In the following table the time is given in minutes after which all (1007.) of the animals are in dorsal position (see table 3) Table 3 Active Substance 1007, of the animals in dorsal position after X minutes 0-methyl 0- (2 , 2 , 2- trichloroethyl) 0-(2' , 2 ' -drbromovinyl) phosphate 5 0-m thyl 0- ( 2 , 2 , 2- trifuloroethy1) 0-(2' , 2.' -dibromovinyl) phosphate 15 0-methyl 0- ( 2 , 2 , 2- trifluoroethyl) 0-(2' , 2 ' -dichlorovinyl) phosphate 0-methyl 0-[l" ,1' -dimethyl-2' ,2' ,2* -trichloroethyl ] 0-[ 2, 2 -dichlorovinyl] phosphate (comparison) no activity 4 . Effect as insecticidal_contact_2oisgn_ a) 50 g of wheat are mixed' ith 100 nig of a 1% dust; granary weevils (Sitophilus granaria) are then added. The animals are then kept at 2 2 - 24 ° C under normal conditions. The test was evaluated after 1 , 2 and 5 days. b) 2 0 g of a 1% dust are evenly distributed in Petri, dishes. Cockroaches (Phyllodromia germanica and Periplaneta americana) are then placed in the dishes and kept under normal conditions at 2 2 - 24°C. ■c) Tomato plants infested with citrus mealybugs (Planococcus citri) are sprayed with a O . 0 257o emulsion (produced from a 10% emulsifiable concentrate) and kept in a greenhouse at 24°C and 7 07o relative humidity.

In the following table the time is given after which the animals of the tests (a) , (b) , and (c) were in dorsal position, (see table 4) Table 4 Active Substance 1007c of the animals in dorsal pos a) granary weevils b) cockroaches after days after minute : O-methyl 0- ( 2 , 2 , 2- richloroethyl) 0-(2' , 2 ' -dibromovinyl) phosphate 1 85 : 0-methyl 0- ( 2 , 2 , 2-trifluoroethyl) 0- (2 2 ' -dibromovinyl) phosphate 1 . 0-methyl 0- (2 ; 2 , 2-trichloroethyl) 0-(2' .2 ' -dichlorovinyl) phosphate 1 30 0-methyl 0- (2 , 2 , 2-trifluoroethyl) 0-(2! , 2 ' -dichlorovinyl ) phosphate 1 25 0-methyl 0-[l' ,1' -dimethyl-2' ,2' ,2 t _ . trichloroethyl] 0-[2 ,2-dichlorovinyl] phosphate (comparison) no activity no activity The following examples illustrate the production" of the active substances according to the invention. The temperatures are given in degrees centigrade. The table which follows contains other examples of 0-(2,2,2-trihalo) 0-(2' , 2 * -dihalo-vinyl) phosphates which have been produced by the methods described. ample 1 . 129 g of trimethyl phosphite, 155 g of 2 , 2 , 2- trichloroethanol and 0.5 g of sodium are heated together to 110°. The methanol which forms is continuously distilled off. During a period of 3 hours the inner temperature is raised from 98° to 150°. After this the reaction mixture is distilled at 12 Torr. 130.6 g of 0,0-dimethyl 0-(2,2,2- trichloroethyl) phosphite having a boiling point of 40-47° at 0.1 to 0.2 Torr, are obtained.

Analysis : calculated: C 19.90% H 3.34% Cl 44.04% P 12.85% found: 20.6 % 3.6 % 43.7 % . 12,8 % 38.8 g (24.5 ml) of phosphorus trichloride are added dropwise with cooling at 0° to 5° to 70 g of trimethyl phosphite. The mixture is' first stirred at 0° to 5° and then at room temperature for 16 hours. The reaction mixture is diluted with 800 ml of benzene and then added dropwise at 20° to 25°, to a solution of 126 g of 2 , 2 , 2- trichloroethanol and 85.4 g of triethyl- arnine in 200 ml of benzene, whereby a white precipitate of triethylamine hydrochloride separates. After completion of the addition, the mixture is stirred for another hour at room temperature. The precipitated salt is removed by filtration and the filtrate is concentrated in vacuum. By distilling the residue, 47.5 g of 0,0-dimethyl 0- (2 , 2 , 2- trichloroethyl) phosphite, b.p. 43-45° at 0.25 Torr, are. obtained.

Analysis : calculated: C 19..90% H .3.43% CI 44.04% found: 20.2 % 3.4 44 ,,3 % . 50 g of 0 ,0- dimethyl 0- (2 , 2 , 2- richloroethyl) phosphite are added dropwise at 25° to 58.2 g (21.8 ml) of technical bromal. The exothermic reaction is kept at 50° with a cooling bath. The mixture is then heated to 80° for 15 minutes and subsequently distilled in high vacuum. The 0-methyl 0- (2 , 2 , 2- trichloroeth l) 0- (21 , 2 ' -dibromovinyl) phosphate has a boiling point of 125-129°/ 0.01 Torr (yield: 32.4 g) .

Analysis : calculated: C 14.05% H 1.42%. CI 24.907.. P found: 14.4.% 1.5 % 25.5 % Example 2 97 g of phosphorus trichloride are added dropwise at 0° during 2 hours to 175 g of trimethyl phosphite. The solution is diluted with 2 liters of benzene and during 2 hours a solution of 315 g of 2 , 2 , 2- t ichloroethanol and 213 g of triethylamine in 500 ml of benzene are added dropwise at 15-20°. The triethylamine hydrochloride which precipitates is separated and the filtrate is slowly added dropwise at reftiix .temperature to a solution of 565 g of bromal in 200 ml of benzene. The methyl bromide which' forms during this reaction is continuously removed by distillation.., the completion of the distillation also being the completion of the reaction. Then the reaction mixture is washed with 10% aqueous sodium carbonate solution and concentrated sodium chloride solution (brine) , and dried; the benzene is removed by distillation in vacuum. The residue is distilled in vacuum. 535 g (89% of theory) of 0-methyl 0- (2 , 2 , 2- trichloroethyl) 0- (21 , 21 -dibromovinyl) phosphate (see Example lc) are obtained .

Analysis : calculated: c 19.90% 11 3.34%.. CI 44.04% P 12.85% found: 20.6 % 3.6 % 43.7 12.8% Exam le 3 a) 38.8 g (24.5 ml) of phosphorus trichloride are added dropwise while cooling with an icebath to 0° to 5°, to 70 g (66.3 ml) of trimethyl phosphite. The mixture is first stirred at 0° to 5° and then at room temperature for 16 hours. Then a solution of 84.5 g (60.7 ml) of 2,2 ,2-trifluoroethanol and 85.4 g (116 ml) of triethyl- amine in 200 ml of ether is added dropwise while cooling at 15° to 20°. After completion of the addition, stirring is continued at room temperature for another hour. The salt which precipitates is removed by filtration and the filtrate is concentrated in vacuum. By distilling the residue, 100 g of 0,0-dimethyl 0- (2 , 2 , 2- trifluoroethyl) phosphite having a boiling point of 39-45° at 40 to 50 Torr, are obtained. b) 19.2 g of 0,0-dimethyl 0- (2 , 2 , 2- trifluoroethyl) phosphite are added dropwise at 50° to 14.8 g of technical chloral. After completion of the addition, the mixture is stirred for 3 hours at 50° and for 30 minutes at 70°. The reaction mixture is distilled directly in high vacuum.

After a preliminary run of 5.7 g having a boiling point of 54-55° at 0.003 Torr, consisting of about 907. of the desired product; 13.5 g of 0-methyl 0- (2 , 2 , 2- rifluoroethyl) 0- (21 , 21 -dichloroviny1) phosphate, b.p. 55° at 0.003 Torr, distill over.

Analysis calculat 20.78%: .H .2.08% .CI 24.54% F 19.72%. found : 20.9 % 2.1 % 24.4 % 19.9 % calculat 10.74% found : 10.8..% The following phosphoric acid esters of the Formula were likewise produced according to the previous example Compound physical data 0-methyl 0- (2 , 2 , 2- trifluoroethyl) 0-(2' , 2 ' -dibromovinyl) phosphate b.p. 83°/0.002 Torr 0-methyl 0- ( 2 , 2 , 2- trichloroethyl) 0-(2' , 2 ' -dichlorovinyl) phosphate b.p. 98-100°/ 0.001 Torr The production of pes icidal compositions according to the invention is performed in known manner by intimately mixing and grinding the active substances of the Formula I with suitable carriers, optionally with the' addition of dispersing agents or solvents, which are inert towards the active substances. The novel active substances can be prepared in the following forms: solid preparations: dusts, scattering agents, granulates, (coated granulates, impregnated granulates and homogeneous granulates); water-dispersible concentrates of the active substance: wettable powders, pastes, emulsions; liquid preparations: solutions, aerosols.

The concentration of active substance in these preparations is from 0.01 to 807o. Other biocidally active substances or agents can be admixed with the compositions of the invention. Thus, in addition to the said active substances of the Formula I and salts thereof, the new compositions may contain, for example, other insecticides, fungicides, bactericides, fungistatic and bacteriostatic substances or other nematocides in order to broaden the range of action.

The- compositions according to the invention may also contain plant fertilizers, trace elements, etc. pesticidal compositions according to the invention are presented to illustrate the invention; where not expres stated otherwise, "parts" mean parts by weight.

Dust The following ingredients are used to produce a) a 5% and b) a 2% dust: a) . 5 parts of O-methyl 0- (2 , 2 , 2- trichloroethyl) 0- (21 , 21 -dichlorovinyl) phosphate, 95 parts of talcum; b) 2 parts of 0-methyl 0- (2 , 2 , 2- trichloroethyl) 0-(2' , 21 -dibromovinyl) phosphate, 1 part of highly dispersed silicic acid, 97 . parts of talcum.

The active substances are mixed and ground with the carriers. The dusts obtained are used, for example, for the coiitrol of cockroaches and ants, etc. in buildings, but also in the protection of plants.

Granulate The following ingredients are used to produce a 5% granulate: parts of O-methyl 0- (2 , 2 , 2-trichloroethyl) 0- (21 , 2 ■ -dichlorovinyl) phosphate, 0.25 part of epichlorohydri , 0.25 part of cetyl polyglycol ether, 3.50 parts of polyethylene glycol ("Carbowax") , 91 parts of kaolin (granular size 0.3 - 0.8 mm).

The active ingredient is mixed with epichlorohydrin and dissolved with 6 parts of acetone; then the polyethylene glycol and cetyl polyglycol ether are added. The resulting solution is sprayed onto kaolin and then the acetone is evaporated in vacuum. The granulate obtained is suitable for the protection of plants and stored goods.

Wettable powder To produce a a) 40%, b) 50%, c) 25%, and d) 10% wettable powder, the following components are used: a) -40 parts of.O-methyl 0- (2 , 2 , 2- trichloroethyl) 0- (2 ' , 2 ' -dichlorovinyl) phosphate, parts of sodium lignin sulphonate, 1 part of sodium dibutyl-naphthalene sulphonate 54 parts of silicic acid; b) 50 parts of 0-methyl 0- (2 , 2 , 2- trichloroethyl) 0-(2' ,2' -dichlorovinyl) phosphate, parts of alkyl aryl sulphonate ("Tinovetine B") , parts of calcium lignin sulphonate, 1 part of Champagne chalk/hydroxyethyl cellulose · mixture (1:1), parts of silicic acid, 14 parts of kaolin; c) 25 parts of 0-methyl 0- (2 , 2 , 2- trifluoroethyl) 0- (2 ' , 2 ' -dibromovinyl) phosphate, parts of the sodium salt of bleylmethyl tauride, 2.5 parts of naphthalene sulphonic acid/ formaldehyde condensation product, 0.5 part of carboxymethyl cellulose, parts of neutral potassium aluminum silicate, 62 parts of kaolin; d) parts of O-methyl 0- (2 , 2 , 2~ trifluoroethyl) -dichlorovinyl) phosphate, 3 parts of mixture of sodium salts of saturated fatty alcohol sulphates, parts of naphthalene sulphonic acid/ formaldehyde condensation product, 82 parts of kaolin.

The active substances are intimately mixed in suitabl mixers with the additives and ground on appropriate mills and rollers. Wettable powders are obtained which may be diluted with water to suspensions of any desired concentration. Such suspensions are chiefly used in plant protection for the'control of biting and sucking insects.

Spray .

To produce a) a 5% and b) a 2% spray, the following components are used: a) 5 . parts of O-methyl 0- (2 , 2 , 2- trichloroethyl) 0- (21 , 21 -dibromovinyl) phosphate are treated with 1 part of epichlorohydrin and then dissolved in 94 parts of benzine (boiling range 160-190°); b) 2 parts of 0-methyl 0- (2 , 2 , 2-dichloroethyl) 0- (21 , 2 ' -dichlorovinyl) phosphate and 3 parts of 4,4,-dichlorodiphenyl-trichloroethane- active substance . are dissolved in 95 parts of kerosene.

These solutions are sprayed with pressure sprayers. The solution (a) is advantageously used for the control of aphids on fruit trees and other plants. The solution (b) is used in particular for the control of flies and mosquitoes in living quarters, warehouses and slaughterhouses.

Claims (7)

What we claim is:

1. New 0-methyl 0- (2 , 2 ,2- trihaloethyl) 0-(2\2'- dihalovinyl) phosphates of the Formula I wherein represents fluorine or chlorine, and Y represents chlorine or bromine,

2. 0-methyl 0-(2 ,2 , 2 -trichloroethyl) 0-(2' ,2' .dibromo- vinyl) phosphate.

3. Process for the production of 0-methyl 0- (2,2,2- trihaloethyl) 0- (2 ' , 2 ' -dihalovinyl) phosphates of the Formula I defined in Claim 1, which comprises converting trimethyl phosphite or 0,0-dimethyl phosphorous acid chloride in the presence of a base with a trihaloethanol of the Formula II CX3CH2OH (II) wherein X represents fluorine or chlorine, into an 0,0-dimethyl 0- (2 , 2 , 2- trihaloethyl) phosphite and reacting this with chloral or bromal. .4, Process according to Claim 3, which comprises ■ reacting trimethyl phosphite and phosphorus trichloride in the presence of an acid-binding agent with one equivalent of 2 , 2 , 2- trihaloethanol of Formula II and then with chloral or bromal.

4

5. Process according to Claim -5-, which comprises reacting trimethyl phosphite and phosphorous trichloride with 2,2,2- \t trihaloethanol and chloral or bromal without isolating the intermediate product 0,0-dimethyl 0-(2 , 2 , 2 -trihaloethyl) phosphite.

6. Pesticidal composition, which comprises as active ingredient at least one 0 -methyl 0- (2, 2 ,2-trihaloethyl) 0 - (2 ', 21 -dihalovinyl) phosphate of the Formula I defined in Claim 1 together with carriers and/or dispersing agents suitable for the protection of plants and optionally with other herbicid-ally and biocidally active ingredients.

7. Method for the control of pests, which comprises applying to said pests a pesticidally effective amount of an 0 -methyl" 0-(2,2,2-trihaloethyl) 0- (2 2 '-dihalovinyl) phosphate of the Formula I as defined in Claim 1 or of compositions containing such phosphates as active ingredients.