GB1601344A - Halogenated cyclopropane esters useful as insecticides and intermediates therefor - Google Patents

Description

(54) HALOGENATED CYCLOPROPANE ESTERS USEFUL AS INSECTICIDES AND INTERMEDIATES THEREFOR (71) We, IMPERIAL CHEMICAL INDUSTRIES LIMITED, Imperial Chemical House, Millbank, London SW1P 3JF, a British Company, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention relates to novel cyclopropane derivatives useful as insecticides, to processes for their preparation, to compositions comprising them and to methods of combating insect and similar invertebrate pests using them.

Certain naturally occurring esters of cyclopropane carboxylic acids have long been known to possess insecticidal properties, but these compounds have been too easily degraded by ultra violet light to be of much use in agriculture. Several groups of synthetic compounds based on cyclopropane carboxylic acids (for example those disclosed in British patent specifications nos. 1,243,858 and 1,413,491) have been evaluated in an attempt to discover compounds of sufficient light stability for use as general agricultural insecticides.

We have now discovered that compounds according to the general formula:

wherein R' and R2 are both haloalkyl groups containing 1 or 2 carbon atoms or in which one of Rl and R2 is such a haloalkyl group and the other is a methyl group, and in which R is a phenoxybenzyloxy group optionally substituted in the a- position by a cyano or ethynyl group have very good insecticidal properties combined with good resistance to light degradation, and that similar compounds wherein R is a hydroxy group or an alkoxy group containing up to 6 carbon atoms, or a halogen atom are useful as intermediates for the preparation of insecticides.

Where R is a phenoxybenzyloxy or a-substituted phenoxybenzyloxy group it is preferably a 3-phenoxybenzyloxy or a-substituted^3-phenoxybenzyloxy group.

In one aspect therefore the present invention provides compounds according to the general formula:

wherein one of R' and R2 represents a group of formula: W--(CF,),- where W represents an atom of hydrogen, fluorine or chlorine and m has the value one or two, and the other of R' and R2 represents a group of formula:

where each of X, Y and Z independently represents an atom of hydrogen, fluorine or chlorine, and R3 represents an atom of hydrogen or the cyano or ethynyl group.

One preferred group of compounds within the invention are those according to the general formula I given above in which one of R1 and R2 represents a group of formula: WCF2- where W represents an atom of hydrogen, fluorine or chlorine. and the other of Rl and R2 represents a group of formula:

where X, Y and Z are as defined above, and R3 represents an atom of hydrogen or the cyano group. Within this preferred group of compounds those which are particularly preferred are those wherein Rl and R2 are both trifluoromethyl groups.

It will be appreciated by those skilled in the art that the compounds represented by formula I are capable of existing in various geometrical and stereoisomeric forms. Thus there may be cis and trans isomers arising from the substitution pattern of the cyclopropane ring, and E- and Z-isomers arising from the substituted vinyl group when R' is not the same as R2. In addition two of the three carbon atoms of the cyclopropane are capable of existing in either R- or Sconfigurations since they are asymmetrically substituted, and when R3 is not hydrogen the carbon atom to which it is attached is also capable of existing in either the R- or S-configuration.

Thus for a compound according to formula I where R' and R2 are the same and R3 is hydrogen, there are four isomeric possibilities, arising from the cyclopropane ring substitution. These may be named by reference to their absolute configuration as (IR, 3R), (IR, 3S), (IS, 3S) and (1S, 3R). When R3 is not hydrogen there are eight possible isomers since each of the four possible cyclopropane ring configurations must exist in two forms, one corresponding to the S-configuration and one to the R-configuration of the carbon atom bearing the R3 group.

Alternatively if R3 is hydrogen, and R' is not the same as R2 there are again eight isomeric possibilities since each of the four possible cyclopropane ring configurations must exist in two forms, one corresponding to the Z-configuration and one to the E-configuration of the vinyl group.

Finally when R' is not the same as R2, and R3 is not hydrogen, each compound may exist in sixteen isomeric forms.

In Table I there are listed compounds according to the invention. Each of the compounds listed is a racemic mixture of (+) and (-) isomers, although a distinction is made between cis and trans substitution on the cyclopropane ring and E- and Z-substitution in the vinyl group where this is present.

The compounds of Table I all conform to the following formula:

TABLE I

Configuration of Compound Cyclopropane Ring No. R1 R2 R3 Substituents 1 CF3 CF3 CN cis 2 CF3 CF3 CN trans 3 CF3 CF3 H cis 4 CF3 CF3 H trans 5 CHF2 CHF2 H cis 6 CHF2 CHF2 H trans 7 CHF2 CHF2 CN cis 8 CHF2 CHF2 CN trans 9 CF2CI CF2CI H cis 10 CF2Cl CF2Cl H trans 11 CF2Cl CF2CI CN cis 12 CF2CI CF2CI CN trans 13 CF3 CF3 C#CH cis 14 CF3 CF3 C#CH trans 15 CHF2 CF3 CN cis 16 CF3 CHF2 CN cis 17 CHF2 CF3 CN trans 18 CF3 CHF2 CN trans 19 CH3 CF3 CN cis 20 CF3 CH3 CN cis 21 CH3 CF3 CN trans 22 CF3 CH3 CN trans 23 CH3 CF3 H cis 24 CF3 CH3 H cis 25 CH3 CF3 H trans 26 CF3 CH3 H trans 27 CHF2 CF2CI CN cis 28 CF2CI CHF2 CN cis 29 CHF2 CF2CI CN trans 30 CF2CI CHF2 CN trans Particularly useful compounds of formula I according to the invention include: (#) - α - cyano - 3 - phenoxybenzyl (+).- cis/trans - 3 - (3,3,3 - trifluoro - 2 trifluoromethylprop - 1 - en - yl) - 2,2 - dimethylcyclopropane carboxylate, 3 - phenoxybenzyl (#) - cis/trans - 3 - (3,3,3 - trifluoro - 2 trifluoromethylprop - 1 - en - 1 - yl) - 2,2 - dimethylcyclopropane carboxylate.

The compounds of the invention according to Formula I are esters and may be prepared by conventional esterification processes, of which the following are examples.

(a) An acid of formula:

where R1 and an have any of the meanings given hereinabove, may be reacted directly with an alcohol of formula:

where R3 represents the hydrogen atom, or the cyano or ethynyl group, the reaction preferably taking place in the presence of an acid catalyst. for example.

dry hydrogen chloride, (b) An acid halide of formula:

where Q represents a halogen atom, preferably a chlorine atom, and R1 and R2 have any of the meanings given hereinabove, may be reacted with an alcohol of formula:

wherein R3 represents the hydrogen atom or the cyano or ethynyl group, the reaction preferably taking place in the presence of a base, for example, pyridine, alkali metal hydroxide or carbonate, or alkali metal alkoxide. As an alternative when R3 is to be the cyano group, a mixture of alkali metal cyanide and 3 phenoxybenzaldehyde may be employed in place of a - cyano - 3 - phenoxybenzyl alcohol.

(c) An acid of formula:

or, preferably, an alkali metal salt thereof, may be reacted with a halide of formula:

where Q' represents a halogen atom, preferably the chlorine atom, and R3 represents the hydrogen atom, or the cyano or ethynyl group, or with the quaternary ammonium salts derived from such halides with tertiary amines, for example pyridine, or trialkyl amines such as triethylamine.

(d) A lower alkyl ester of formula:

where R4 represents a lower alkyl group containing up to six carbon atoms, preferably the methyl or ethyl group, and Rl and R2 have any of the meanings given hereinabove, is heated with an alcohol of formula:

to effect a transesterification reaction. Preferably the process is performed in the presence of a suitable catalyst, for example, an alkali metal alkoxide, such as sodium methoxide, or an alkylated titanium derivative, such as tetramethyl titanate.

All of these conventional processes for the preparation of esters may be carried out using solvents and diluents for the various reactants where appropriate, and may be accelerated or lead to higher yields of product when performed at elevated temperatures or in the presence of appropriate catalysts, for example phase-transfer catalysts.

The preparation of individual isomers may be carried out in the same manner but commencing from the corresponding individual isomers of compounds of formula II. These may be obtained by conventional isomer separation techniques from mixtures of isomers. Thus cis and trans isomers may be separated by fractional crystallisation of the carboxylic acids or salts thereof, whilst the various optically active species may be obtained by fractional crystallisation of salts of the acids with optically active amines, followed by regeneration of the optically pure acid.

The optically pure isomeric form of the acid (or its equivalent acid chloride or ester) may then be reacted with 3-phenoxybenzyl alcohol to produce the compounds of formula I in the form of an individually pure isomer thereof. In the case of a - cyano - 3 - phenoxybenzyl alcohol the product will be a mixture of two isomers since it is not possible to react optically pure a- cyano - 3 phenoxybenzyl alcohol with the acid or its equivalent without racemisation of the alcohol occurring. A typical product of this procedure is: (+) - a - cyano - 3 - phenoxybenzyl (lR,3R) - 3 - (3,3,3 - trifluoro - 2 trifluoromethylprop - 1 - en - 1 - yl) - 2,2 - dimethylcyclopropane carboxylate.

This compound is believed to be especially useful as an insecticide.

The preparation of single isomers of these compounds may be achieved by preparing the optically pure acid chloride and reacting it with (+)- 3 phenoxymandelamide to give the corresponding (+) - a - carboxamido ester. The two isomeric esters may be separated by fractional crystallisation, and individually subjected to dehydration to the corresponding a - cyano - 3 - phenoxybenzyl ester. In this way the following single isomer may be obtained.

(S) - a - cyano - 3 - phenoxybenzyl (lR,3R) - 3 - (3,3,3 - trifluoro - 2 trifluoromethylprop - 1 - en - 1 - yl) - 2,2 - dimethylcyclopropane carboxylate.

which is believed to be the insecticidally most effective isomer of that particular compound.

The various cyclopropane compounds referred to hereinabove as being useful as intermediates in the processes by which the invention compounds of Formula I may be prepared are themselves novel compounds.

In further aspect therefore the present invention provides compounds according to the general formula:

wherein one of R' and R2 represents a group of formula: W-(C F2)m where W represents an atom of hydrogen, fluorine or chlorine and m has the value one or two, and the other of R' and R2 represents a group of formula:

where each of X, Y and Z independently represents an atom of hydrogen fluorine or chloride, and Q represents the hydroxy group, a lower alkoxy group containing up to six carbon atoms, or the chlorine or bromine atom.

One preferred group of intermediates within the invention are those according to the general formula II given above in which one of R' and R2 represents a group of formula: WCF2- where W represents an atom of hydrogen, fluorine or chlorine, and the other of R' and R2 represents a group of formula:

where X, Y and Z are as defined above, and Q represents the hydroxy group a lower alkoxy group containing from one to three carbon atoms, or the chlorine or bromine atom. Within this preferred group of compounds those which are particularly preferred are those wherein R1 and R2 are both trifluoromethyl groups.

The compounds represented by formula II are also capable of existing in various geometrical and stereoisomeric forms in the same way as the compounds of formula I. Thus there may be cis and trans isomers arising from the substitution pattern of the cyclopropane ring, and E- and Z-isomers arising from the substituted vinyl group when R1 is not the same as R2. In addition two of the three carbon atoms of the cyclopropane are capable of existing in either R- or S-configurations since they are asymmetrically substituted.

Examples of specific intermediate compounds according to the invention include those represented by the following general formula:

wherein R1 and R2 have the specific meanings given in Table I hereinabove for the corresponding compounds of formula I and wherein Q represents a chlorine atom a hydroxy group or an ethoxy group.

The compounds of formula II wherein Q is hydroxy may be obtained by hydrolysis of the compounds of formula II wherein Q is lower alkoxy, and may be converted to the compounds of formula II wherein Q is chloro or bromo by reaction with for example thionyl chloride or thionyl bromide respectively. All of the compounds of formula II may be used either directly or indirectly to prepare the insecticidally active esters of formula I, as described hereinabove.

The compounds of formula II wherein Q is lower alkoxy may be prepared by a variety of processes. One method involves reacting a diene of formula:

with a lower alkyl ester of diazoacetic acid. This gives rise to the required compound of formula II directly. The process is conveniently conducted using an excess of the diene as a solvent for the alkyl diazoacetate in the presence of a metallic catalyst, for example powdered copper or copper bronze.

The compounds of formula (V) and their preparation are described and claimed in our copending application 8023072, (Serial No. 1601346).

In a variation of the above process a compound of formula III may be obtained by the reaction of the unsaturated alcohol of formula IV with alkyl diazoacetate, and may be converted to a compound of formula II where Q is lower alkoxy by dehydration with a chemical dehydrating agent, for example, phosphorus pentoxide.

This variant of the diazoacetate process is very useful for the preparation of compounds where R' and R2 are both trifluoromethyl groups, or wherein one of R' and RZ is trifluoromethyl and the other is difluoromethyl.

The compounds of formula (IV) and their preparation are described and claimed in our copending application 8023071, (Serial No. 1601345).

The compounds of formula IV may be obtained by reacting a ketone of formula:

with 3-methylbut-l-ene, preferably under pressure. The corresponding compounds of formula V may be obtained by dehydration, with e.g. phosphorus pentoxide, of the compounds of formula IV.

The compounds of formula V wherein R' and R2 are both haloalkyl groups or wherein one of R' and R2 is a haloalkyl group and the other is a methyl group may also be obtained by reacting the corresponding ketone of formula:

with the ylid obtained by treating a 3,3-dimethylallyl triphenylphosphonium halide, preferably the chloride or bromide, with a suitable dehydrohalogenating agent, for example an alkyllithium compound such as n-butyllithium. The phosphonium halide may be obtained by reacting triphenyl phosphine with a 3,3-dimethylallyl halide. Dienes which may be obtained by this process include those of formula V wherein R1 and R2 are as defined in the following table:

R' R3 CF3 CF3 CHF2 CHF2 CF3 CHEF, CF3 CM3 CF2Cl CF2CI CHF2 CF2Cl Examples of compounds of formula IV are 5 - hydroxy - 2 - methyl - 6,6,6 trifluoro - 5 - trifluoromethylhex - 2 - ene and 5 - hydroxy - 2 - methyl - 6.6 difluoro - 5 - trifluoromethylhex - 2 - ene, and these may be dehydrated to 2 methyl - 6,6,6 - trifluoro - 5 - trifluoromethylhexa - 2,4 - diene and 2 - methyl 6,6 - difluoro - 5 - trifluoromethylhexa - 2,4 - diene as examples of compounds of formula V.

Another method of preparing the compounds of formula 11 where Q is alkoxy involves the base induced ring closure of a compound of formula:

wherein R' and R2 have any of the meanings given above, Q is alkoxy, and W' and W" are each either fluorine, chlorine or bromine, provided that W' is bromine when R2 is bromine.

Suitable bases for carrying out the process include tertiary amines, for example pyridine, triethylamine, diethylaniline and N-methylpiperidine, and also alkali metal lower alkoxides, that is those containing up to six carbon atoms, for example sodium methoxide, sodium ethoxide, and sodium and potassium tbutoxide. The step is conveniently carried out in a diluent or solvent for the reactant and the base. A particularly convenient manner of conducting this process is to treat a solution of the compound of formula III in an alcohol corresponding to the alkali metal alkoxide being used for a period of from 0.5 to 20 hours.

At least two moles of base are required to convert the compounds of formula VII to the compounds of formula II where R is alkoxy, and this involves two separate stages, cyclisation and p-elimination of hydrogen halide, but it is not clear in what order these two stages proceed or if they proceed simultaneously.

When the process is conducted using only one molar equivalent of base three different products are obtained corresponding to the following formulae:

Each of these species on treatment with a further molar equivalent of base gives the compound of formula III, and in a further aspect therefore the invention provides a process for preparing the compounds of formula II where Q is alkoxy by treating a compound of formula A, B or C with at least one molar equivalent of a base.

The compounds of formula VII useful as intermediates in the preparation of the compounds of formula II may be prepared by reacting a compound of formula:

wherein Q is alkoxy, with a compound of formula:

wherein R', R2, W' and W" have any of the meanings given hereinbefore, in the presence of a free radical initiator. This may be a physical initiator such as irradiation with a suitable e.g. ultra violet, light source, or a conventional chemical free radical catalyst, such as e.g. benzoyl peroxide or azobisisobutyronitrile. The process may conveniently be carried out by using an excess of the compound of formula V as a diluent, at temperatures in the range 50"C to 150"C, preferably 80 to 1200C for periods of from 1 to 20 hours, optionally in a sealed system and under the autogenic pressure of the reaction.

A particularly useful compound of formula VIII is ethyl 3,3-dimethylpent-4enoate, although other lower alkyl esters may also be used.

The ester of 3,3-dimethylpent-4-enoic acid represented by formula VIII may be replaced by other compounds in which the carboxylate function is replaced by an equivalent function, by which we mean a functional group which does not interfere with the process set out hereinabove but which may subsequently be chemically modified by oxidation or hydrolysis to give the carboxylic acid, for example the nitrile, acetyl, or formyl group. Alternatively the compound of formula VIII may be replaced by a compound of formula:

where Q' is selected from alkoxycarbonyl, cyano and acetyl and Q" is cyano or alkoxycarbonyl.

A yet further process by which the compounds of formula II wherein Q is alkoxy may be prepared involved the reaction of a diene of formula V with an alkyl malonate in the presence of a reducible copper salt, and optionally in the presence of another salt selected from halides of Group I and Group II metals such as lithium chloride or calcium chloride. The initial product which has the formula:

wherein R', R2, and Q" have the meanings given above and Q is alkoxy, may be converted to the required products of formula II by conventional hydrolytic and esterification procedures.

When the various processes for the preparation of the intermediates of formula II are carried out the products are usually mixtures of the various geometrical isomers. Thus the processes may lead to a mixture of cis and trans isomers, often with one form predominating, and, in the cases where R1 is not the same as R2, Z- and E-isomers of both cis and trans forms, again often with one form predominating.

Unless these forms are separated by some physical process, e.g. fractional crystallisation of the carboxylic acids, the final products of formula I will also consist of mixtures of the various isomers, containing more than one of the compounds of Table 1. Typical examples of insecticidally active products, most of which are mixtures of more than one compound, which have been obtained include those set out hereinbelow.

Product No. 1: A mixture of 1 part of compound No. I with 4 parts of compound No. 2.

Product No. 2: A mixture of 1 part of compound No. 1 with 1 part of compound No. 2.

Product No. 3: Compound No. 2 alone.

Product No. 4: Compound No. 1 alone.

Product No. 5: A mixture of li parts of compound No. 3 with 14 parts of compound No. 4.

Product No. 6: A mixture of compounds Nos. 15, 16, 17 and 18 (composition undetermined).

Product No. 7: A mixture of 1 part of compound No. 19, 9 parts of compound No. 20, 1 part of compound No. 21 and 9 parts of compound No. 22.

Product No. 8: A mixture of 1 part of compound No. 23, 9 parts of compound No. 24, 1 part of compound No. 25 and 9 parts of compound No. 26.

Product No. 9: A mixture of 1 part of compound No. 1 with 2 parts of compound No. 2: Product No. 10: A mixture of 3 parts of compound No. 5 with 2 parts of compound No. 6.

Product Neo. 11: A mixture of 3 parts of compound No. 7 with 2 parts of compound No. 8.

Product No. 12: A mixture of 7 parts of compound No. 9 with 13 parts of compound No. 10.

Product No. 13: A mixture of 7 parts of compound No. 11 with 13 parts of compound No. 12.

Product No. 14: A mixture undetermined compositions containing compounds 27, 28, 29 and 30.

Product No. 15: A mixture of 2 parts of compound No. 13 with 3 parts of compound No. 14.

The compounds of formula I may be used to combat and control infestations of insect pests and also other invertebrate pests, for example, acarine pests. The insect and acarine pests which may be combated and controlled by the use of the invention compounds include those pests associated with agriculture (which term includes the growing of crops for food and fibre products, horticulture and animal husbandry), forestry, the storage of products of vegetable origin, such as fruit, grain and timber, and also those pests associated with the transmission of diseases of man and animals.

In order to apply the compounds to the locus of the pests they are usually formulated into compositions which include in addition to the insecticidally active ingredient or ingredients of formula I suitable inert diluent or carrier materials, and/or surface active agents. The compositions may also comprise another pesticidal material, for example another insecticide or acaricide, or a fungicide, or may also comprise a insecticide synergist, such as for example dodecyl imidazole, safroxan, or piperonyl butoxide. The compositions may be in the form of dusting powders wherein the active ingredient is mixed with a solid diluent or carrier, for example kaolin, bentonite, kieselguhr, or talc, or they may be in the form of granules, wherein the active ingredient is absorbed in a porous granular material for example pumice.

Alternatively the compositions may be in the form of liquid preparations to be used as dips or sprays. which are generally aqueous dispersions or emulsions of the active ingredient in the presence of one or more known wetting agents, dispersing agents or emulsifying agents (surface active agents).

Wetting agents, dispersing agents and emulsifying agents may be of the cationic, anionic or non-ionic type. Suitable agents of the cationic type include, for example, quaternary ammonium compounds, for example, cetyltrimethyl ammonium bromide. Suitable agents of the anionic type include, for example, soaps. salts of aliphatic monoesters or sulphuric acid, for example sodium lauryl sulphate. salts of sulphonated aromatic compounds, for example sodium dodecylbenzenesulphonate, sodium, calcium or ammonium lignosulphonate, butylnaphthalene sulphonate, and a mixture of the sodium salts of diisopropyl- and triisopropylnaphthalene sulphonates. Suitable agents of the non-ionic type include.

for example, the condensation products of ethylene oxide with fatty alcohols such as oleyl alcohol or cetyl alcohol, or with alkyl phenols such as octyl phenol, nonyl phenol and octylcresol. Other non-ionic agents are the partial esters derived from long chain fatty acids and hexitol anhydrides, the condensation products of the said partial esters with ethylene oxide, and the lecithins.

The compositions may be prepared by dissolving the active ingredient in a suitable solvent, for example. a ketonic solvent such as diacetone alcohol, or an aromatic solvent such as trimethylbenzene and adding the mixture so obtained to water which may contain one or more known wetting, dispersing or emulsifying agents. Other suitable organic solvents are dimethyl formamide, ethylene dichloride, isopropyl alcohol, propylene glycol and other glycols, diacetone alcohol, toluene, kerosene, white oil, methylnaphthalene, xylenes and trichloroethylene, N-methyl-2-pyrrolidone and tetrahydro furfuryl alcohol (THFA).

The compositions to be used as sprays may also be in the form of aerosols wherein the formulation is held in a container under pressure in the presence of a propellant such as fluorotrichloromethane or dichlorodifluoromethane. The compositions which are to be used in the form of aqueous dispersions or emulsions are generally supplied in the form of a concentrate containing a high proportion of the active ingredient or ingredients, the said concentrate to be diluted with water before use. These concentrates are often required to withstand storage for prolonged periods and after such- storage, to be capable of dilution with water to form aqueous preparations which remain homogeneous for a sufficient time to enable them to be applied by conventional spray eq

The following Examples illustrate the various aspects of the invention.

EXAMPLE 1 This Example illustrates the preparation of 1 - chloro - 1,1 - difluoro - 2 chlorodifluoromethyl - 5 - methylhexa - 2,4 - diene, of formula:

(a) Preparation of 3,3-dimethylallyl triphenylphosphonium bromide.

A mixture of 3,3-dimethylallyl bromide (50.0 g), triphenylphosphine (88.0 g) and dry toluene (500 ml) was stirred and heated at the reflux temperature for one hour, and then kept at the ambient temperature for 18 hours. The white precipitate of 3,3 - dimethylallyl triphenylphosphonium bromide (m.p. 242"C) was collected by filtration, washed with diethyl ether and dried.

(b) Preparation of 1 - chloro - 1,1 - difluoro - 2 - chlorodifluoromethyl - 5 methylhexa - 2,4 - diene.

n - Butyl lithium (65.0 ml of a 15% w/w solution in hexane) was slowly added to a vigorously stirred suspension of 3,3 - dimethylallyl triphenylphosphonium bromide (65.0 g) in dry petroleum ether (boiling range 30-400C, 500 ml) at OOC under a nitrogen atmosphere, after which the mixture was kept at the ambient temperature for 18 hours. The mixture was then cooled to OOC, and 1,3dichlorotetrafluoroacetone (31.44 g) was added. The mixture was then permitted to attain the ambient temperature over a period of two hours. and the precipitate removed by filtration. The filtrate was concentrated by evaporation, until the volume was about 70 ml, and passed through a short alumina column, after which the remaining solvent was evaporated at atmospheric pressure at a temperature of 690C. The residual liquid was subjected to fractional distillation, and the fraction boiling at 79-800C/20 mm Hg collected and identified by infra red and nuclear magnetic resonance spectroscopy as 1 - chloro - 1,1 - difluoro - 2 chlorodifluoromethyl - 5 - methylhexa - 2,4 - diene.

N.m.r. (CCl4) p.p.m. 1.88-1.94 (m, 6H); 6.3 (d, 1H); 7.08 (d, 1H).

EXAMPLE 2 By similar procedures to that illustrated in Example 1 other dienes were prepared from the appropriate ketones, as follows: (i) 2 - Methyl - 5 - trifluoromethylhexa - 2,4 - diene was prepared from 1,1,1 - trifluoroacetone.

N.m.r. (CCl4) p.p.m. 1.761.82 (m, 9H); 5.856.00 (m, IH); 6.626.78 (m, 1H).

(ii) 1,1 - Difluoro - 2 - chlorodifluoromethyl - 5 - methylhexa - 2,4 - diene was prepared from 1 - chloro - 1,1,2,2 - tetrafluoroacetone.

Infra red (liquid filmy3000, 1650, 1265 cm-1.

(iii) 1,1 - Difluoro - 2 - difluoromethyl - 5 - methylhexa - 2,4 - diene was prepared from 1,1,3,3 - tetrafluoroacetone.

N.m.r. (CCl4) p.p.m. 1.902.02 (m, 6H); 5.65-7.10 (m, 4H).

EXAMPLE 3 This Example illustrates the preparation of 5 - hydroxy - 2 - methyl - 6,6,6 trifluoro - 5 - trifluoromethylhex - 2 - ene.

A stirred mixture of hexafluoroacetone (235 g) and 3 - methylbut - 1 - ene (100 g) was heated at 1250C under a pressure of 17 atmospheres for a period of 20 hours. Distillation of the product mixture under reduced pressure yielded 5 hydroxy - 2 - methyl - 6,6,6 - trifluoro - 5 - trifluoromethylhex - 2 - ene as a mobile colourless liquid, b.p. 43"C/15 mm Hg.

N.m.r. (CCl4) p.p.m. 1.77 (d, 6H); 2.58-3.00 (m, 3H); 5.05.4 (m, IH).

EXAMPLE 4 By the use of a procedure similar to that illustrated in Example 3 5 - hydroxy 2 - methyl - 6,6 - difluoro - 5 - trifluoromethylhex - 2 - ene was prepared from pentafluoroacetone.

N.m.r. (CCl4) p.p.m. 1.78 (d, 6H); 2.5-2.75 (m, 3H); 5.18 (m, 1H); 5.80 (t, lH).

EXAMPLE 5 This Example illustrates the preparation of ethyl (+)cis/trans - 3 - (2 hydroxy - 3,3,3 - trifluoro - 2- trifluoromethylprop - 1 - yl) - 2,2 dimethylcyclopropane carboxylate.

A solution of ethyl diazoacetate (9.12 g) in dichloromethane (400 ml) was added dropwise over a period of 48 hours to 5 - hydroxy - 2 - methyl - 6,6,6 trifluoro - 5 - trifluromethylhex - 2 - ene (18.9 g) in the presence of a catalytic amount of anhydrous copper (II) sulphate at 110120 C.

The resultant mixture was washed with water, dried over anhydrous magnesium sulphate, and distilled to yield several fractions within the range 6890 C at 0.15 mm. N.m.r., infra red and mass spectral analysis indicated that these fractions consisted principally of the (+) - cis and (+) - trans - isomers of ethyl 3 (2 - hydroxy - 3,3,3 - trifluoro - 2 - trifluoromethylprop - 1 - yl) - 2,2 dimethylcyclopropane carboxylate in different proportions.

N.m.r. (CDCl3) p.p.m. 1.04-1.40(m, 9H); 1.55-2.43 (m, 4H); 4.00--4.37 (m, 2H).

EXAMPLE 6 By the use of a procedure similar to that illustrated in Example 5 5 - hydroxy 2 - methyl - 6,6 - difluoro - 5 - trifluoromethylhex - 2 - ene was converted to ethyl (+) - cis/trans - 3 - (2 - hydroxy - 3,3 - difluoro - 2 - trifluoromethylprop 1 - yl) - 2,2 - dimethylcyclopropane carboxylate.

N.m.r. (CCl4) p.p.m. 1.3-2.4 (m, 13H); 4.0-4.35 (m, 2H); 4.64.8 (m, 1H); 5.2-6.4 (m, 1H).

EXAMPLE 7 This Example illustrates the preparation of ethyl (+) - cis/trans - 3 - (3,3,3 trifluoro - 2 - trifluoromethylprop - 1 - en - 1 - yl) - 2,2 - dimethylcyclopropane carboxylate.

A mixture of ethyl (+) - cis/trans - 3 - (2 - hydroxy - 3,3,3 - trifluoro - 2 trifluoromethylprop - 1 - yl) - 2,2 - dimethylcyclopropane carboxylate (4.62 g), phosphorus oxychloride (2.2 g), and dry pyridine (5.3 ml) was heated at 110 C for a period of 65 hours, after which it was poured into iced water and stirred for 5 hours.

The mixture thus obtained was extracted with diethyl ether, and the extracts washed with water and dried over anhydrous sodium sulphate. After removal of the ether by evaporation under reduced pressure the residual oil was distilled under reduced pressure, and ethyl (c)- cis/trans- 3 - (3,3,3 - trifluoro - 2 trifluoromethylprop - 1 - en - 1 - yl) - 2,2 - dimethylcyclopropane carboxylate was obtained as a colourless oil, b.p. 6W65 /0.5 mm Hg.

N.m.r. (CDCl3) p.p.m. 1.15-1.39 (m, 9H); 1.75-2.60 (m, 2H); 4.02.34 (m, 2H); 6.36 and 7.36 (dd, 1H).

EXAMPLE 8 By the use of a procedure similar to that illustrated in Example 7 ethyl (+) cis/trans - 3 - (3,3 - difluoro - 2 - trifluoromethylprop - 1 - en - 1 - yl) - 2,2 - dimethylcyclopropane carboxylate was obtained from the product of Example 6.

N.m.r. (CCl4) p.p.m. 1.2-1.4 (m, 9H); 1.6-2.6 (m, 2H); 4.0-4.4 (m, 2H); 5.4-7.2 (m, 2H).

EXAMPLE 9 By the use of similar procedures to that illustrated in Example 5 the following ethyl esters of formula II were obtained from the stated dienes by reaction with ethyl diazoacetate.

(i) Ethyl (±) - cis/trans -3 - (3,3 - difluoro - 2 - difluoromethylprop - 1 - en - 1 - yl) - 2,2 - dimethylcyclopropane carboxylate, from 1,1 - difluoro - 2 - difluoromethyl - 5 - methylhexa - 2,4 - diene.

N.m.r. (CCl4) p.p.m. 1.25-144 (m, 9H); 1.602.40 (m, 2H); 4.0-4.30 (m, 2H); 5.58-7.34 (complex, 3H).

(ii) Ethyl (+) - cis/trans - 3 - (E/Z - 2 - trifluoromethylprop - I - en - 1 - yl) 2,2 - dimethylcyclopropane carboxylate, from 2 - trifluoromethyl - 5 methylhexa - 2,4 - diene.

N.m.r. (CCl4) p.p.m. 1.10--1.40 (m, 9H); 1.50-2.10 (m, 5H); 4.0-4.38 (m, 2H); 5.24-6.46 (m, 1H).

(iii) Ethyl (+) - cis/trans - 3 - (3 - chloro - 3,3 - difluoro - 2 chlorodifluoromethylprop - 1 - en - 1 - yl) -2,2 - dimethylcyclopropane carboxylate, from 1 - chloro - 1,1 - difluoro - 2 - chlorodifluoromethyl 5 - methylhexa - 2,4 - diene.

N.m.r. (CCl4) p.p.m. 1.28-1.42 (m, 9H): 1.78-2.60(m, 7H): 4.08-4.26 (m, 2H); 6.20 and 7.16 (dd, 1H).

(iv) Ethyl (+) - cis/trans - 3 - (E/Z - 3,3 - difluoro - 2 chlorodifluoromethylprop - I - en - 1 - yl) - 2,2 - dimethylcyclopropane carboxylate, from 1,1 - difluoro - 2 - chlorodifluoromethyl - 5 methylhexa - 2,4 - diene.

N.m.r. (CCl4) p.p.m. 1.24-1.52 (m, 9H); 1.64-2.50 (m, 2H): 3.90--4.30 (m, 2H): 5.5--7.04 (m, 2H).

EXAMPLE 10 This Example illustrates the preparation of (-+) - cis/trans - 3 - (3,3,3 trifluoro - 2 - trifluoromethylprop - 1 - en - 1 - y1) - 2,2 - dimethylcyclopropane carboxylic acid.

A mixture of ethyl (+) - cis/trans - 3 - (3,3,3 - trifluoro - 2 trifluoromethylprop - I - en - 1 - yl) - 2,2 - dimethylcyclopropane carboxylate (0.52 g), glacial acetic acid (2.52 ml), hydrobromic acid (48 w/v; 3.36 ml), and water (1.12 ml) was heated at the reflux temperature for a period of 10 hours After cooling the mixture it was diluted with water (50 ml) and extracted several times with diethyl ether. The extracts were combined, washed with water, dried over anhydrous sodium sulphate, and concentrated by evaporation of the ether under reduced pressure. The residual oil was shown by spectroscopic analysis to consist principally of (+) - cis/trans - 3 - (3,3,3 - trifluoro - 2 trifluoromethylprop - 1 - en - 1 - yl) - 2,2 - dimethylcyclopropane carboxylic acid.

EXAMPLE 11 This Example illustrates the conversion of (+)- cis/trans - 3 - (3,3,3 trifluoro - 2 - trifluoromethylprop - 1 - en - 1 - yl) - 2,2 - dimethylcyclopropane carboxylic acid to its acid chloride.

A mixture of (+) - cis/trans - 3 - (3,3,3 - trifluoro - 2 - trifluoromethyl prop - 1 - en - 1 - yl) - 2,2 - dimethylcyclopropane carboxylic acid (0.4 g) and thionyl chloride (5.0 ml) was heated at the reflux temperature for a period of 2 hours, after which the excess thionyl chloride was removed by distillation under reduced pressure, leaving (:1:) - cis/trans - 1 - chlorocarbonyl- 3 - (3,3,3 trifluoro - 2 - trifluoromethyl - prop - 1 - en - 1 - yl) - 2,2 dimethylcyclopropane.

EXAMPLE 12 This Example illustrates the preparation of (+)- a - cyano - 3phenoxybenzyl (+) - cis/trans - 3 - (3,3,3 - trifluoro - 2 - trifluoromethylprop 1 - en - 1 - yl) - 2,2 - dimethylcyclopropane carboxylate, herein referred to as Product No. 1.

To the residue of (+) - cis/trans - 1 - chlorocarbonyl - 3 - (3,3,3 - trifluoro 2 - trifluoromethylprop - 1 - en - 1 - yl) - 2,2 - dimethylcyclopropane (obtained in Example 15) was added a mixture of pyridine (0.12 g) and (±) - a - cyano - 3 phenoxybenzyl alcohol (0.33 g) and the mixture thus obtained was stirred for a period of 16 hours at the ambient temperature. Water (20 ml) was added and the mixture extracted with diethyl ether (3x10 ml). The combined extracts were washed with water, saturated sodium bicarbonate solution, and water and dried over anhydrous sodium sulphate. After removal of the ether by evaporation under reduced pressure the residual oil was subjected to preparative thick-layer chromatography, using 2 mm thick silica on glass with chloroform as eluent, to yield (#)-α-cyano - 3 - phenoxybenzyl (+) - cis/trans - 3 - (3,3,3 - trifluoro 2- trifluoromethylprop - 1 - en - 1 - yl) - 2,2 - dimethylcyclopropane carboxylate (Rf 0.53), containing about 20% of the cis - isomer and about 80 o of the trans - isomer. Spectral data: infra red, 1755, 1680, 1600, 1490, 1300, 1160; n.m.r., 0.9-2.5 T, 6.0-6.15 t, 6.35-7.2 T; mass spectrum, M+ 483 (275, 259, 231, 209, 208, 181).

EXAMPLE 13 By the use of procedures similar to those illustrated in Example 10 the following carboxylic acids were prepared from the corresponding ethyl esters.

(i) (+) - cis/trans - 3 - (3,3 - difluoro - 2 - trifluoromethylprop - 1 - en - 1 - yl) - 2,2 - dimethylcyclopropane carboxylic acid.

Infra red (liquid film) 3500--2400, 1700, 1665 cm-1.

(ii) (#) - cis/trans - 3 - (3,3 - difluoro - 2 - difluoromethylprop - I - 3n - I yl) - 2,2 - dimethylcyclopropane carboxylic acid.

N.m.r. (CCl4) p.p.m. 1.30-1.50(m, 6H); 1.70-2.60(complex, 2H); 5.70- 7.13 (complex, 3H).

(iii) (+) - cis/trans - 3 - (E/Z - 2 - trifluoromethylprop - 1 - en - 1 - yl) 2,2 - dimethylcyclopropane carboxylic acid.

N.m.r. (CCl4) p.p.m. 1.22-1.44 (m, 6H); 1.6-2.3 (m, 5H); 5.36-6.6 (m, 111)11.9 (s, lH).

(iv) (+) - cis/trans - 3 - (3 - chloro - 3,3 - difluoro - 2 chlorodifluoromethylprop - 1 - en - 1 - yl) -2,2 - dimethylcyclopropane carboxylic acid.

N.m.r. (CCl4) p.p.m. 1.24-1.42(m, 6H); 1.80-2.68 (m, 2H); 6.16 and 7.12 (dd, 1H); 11.6 (s, 1H).

(v) (*) - cis/trans - 3 - (E/Z - 3,3 - difluoro - 2 - chlorodifluoromethylprop 1 - en - 1 - yl) - 2,2 - dimethylcyclopropane carboxylic acid.

Infra red (CHCl3) 3450-2500, 1705, 1675 cm-1.

EXAMPLE 14 The various carboxylic acids of Example 13 were converted to the insecticidal ester products according to formula I by reacting the acid chlorides with 3 phenoxybenzyl alcohol, (#) - α - cyano - 3 - phenoxybenzyl alcohol or (j) - a - ethynyl - 3 - phenoxybenzyl alcohol. The products of these reactions (herein designated Product Nos. 2 to 15) are for the most part mixtures of more than one of the compounds of Table I, as set out hereinbelow.

Product No. 2: (+) - a - cyano - 3 - phenoxybenzyl (+) - cis/trans - 3 (3,3,3 - trifluoro - 2 - trifluoromethylprop - 1 - en - 1 - yl) - 2,2 - dimethyl cyclopropane carboxylate, is a mixture of 1 part of compound No. 1 with 1 part of compound No. 2.

N.m.r. (CCl4) p.p.m. 1.20-1.40 (m, 6H); 1.80-2.30 (m, 2H); 6.17-6.37 and 6.85-7.42 (mm, 11H).

Product No. 3(1) - a - cyano - 3 - phenoxybenzyl (+) - trans - 3 - (3,3,3 trifluoro - 2- trifluoromethylprop - 1 - en - 1 - y1) - 2,2 dimethylcyclopropane carboxylate, is compound No. 2 alone.

Product No. 4: (+) - a - cyano - 3 - phenoxybenzyl (+) - cis - 3 - (3,3,3 trifluoro - 2 - trifluoromethylprop - 1 - en - 1 - yl) - 2,2 dimethylcyclopropane carboxylate, is compound No. 1 alone.

Product No. 5: 3 - phenoxybenzyl (1) - cis/trans - 3 - (3,3,3 - trifluoro - 2 trifluoromethylprop - 1 - en - 1 - yl) - 2,2 - dimethylcyclopropane carboxylate, is a mixture of 11 parts of compound No. 3 with 14 parts of compound No. 4.

N.m.r. (CCl4) p.p.m. 1.18-1.40 (m, 6H): 1.75-2.55 (m, 2H); 5.15 (s, 2H); 6.30 and 6.70-7.40 (dm, 10H).

Product No. 6: (+) - a - cyano - 3 - phenoxybenzyl (1) - cis/trans - 3 - (3,3 difluoro - 2- trifluoromethylprop - 1 - en - 1 - yl) - 2,2 - dimethylcyclopropane carboxylate, is a mixture of compounds Nos. 15, 16, 17 and 18 (composition undetermined). 1 Infra red (liquid film) 1745, 1665, 1595 em Product No. 7: (+) - a - cyano - 3 - phenoxybenzyl (+) - cis/trans - 3 - (Z/E 2 - trifluoromethylprop - 1 - en - 1 - yl) - 2,2 - dimethylcyclopropane carboxylate is a mixture of I part of compound No. 19, 9 parts of compound No. 20, 1 part of compound No. 21 and 9 parts of compound No. 22.

N.m.r. (CCl4) p.p.m. 1.22-1.40 (m, 6H); 1.60-2.30 (m, 5H); 5.2-6.45 (m, 1H).

Product No. 8: 3 - phenoxy benzyl (+) - cis/trans - 3 - (Z/E - 2 trifluoromethylprop - 1 - en - 1 - yl) - 2,2 - dimethylcyclopropane carboxylate is a mixture of 1 part of compound No. 23, 9 parts of compound No. 24, 1 part of compound No. 25 and 9 parts of compound No. 26.

N.m.r. (CCl4) p.p.m. 1.22-1.40 (m, 6H); 1.58-2.2 (m, 5H); 5.02 (s, 2H); 5.2-6.45 (m, 1H); 6.85-7.42 (m, 9H).

Product No. 9: (+) - a - cyano - 3 - phenoxybenzyl (+) - cis/trans - 3 (3,3,3 - trifluoro - 2 - trifluoromethylprop - 1 - en - 1 - yl) - 2,2 dimethylcyclopropane carboxylate, is a mixture of 1 part of compound No. 1 with 2 parts of compound No. 2.

Product No. 10: 3 - phenoxybenzyl (+) cis/trans - 3 - (3,3 - difluoro - 2 difluoromethylprop - I - en - I - yl) - 2,2 - dimethylcyclopropane carboxylate is a mixture of 3 parts of compound No. 5 with 2 parts of compound No. 6.

N.m.r. (CCl4) p.p.m. 1.18-1.37 (m, 6H); 1.60--2.45 (m. 2H): 5.03-5.1 (m, 2H); 5.13-7.47 (complex, 12H).

Product No. 11: (+) - a - cyano - 3 - phenoxybenzyl (+) - cis/trans - 3 (3,3 - difluoro - 2- difluoromethylprop - 1 - en - I - yl) - 2.2 - dimethylcyclopropane carboxylate is a mixture of 3 parts of compound No. 7 with 2 parts of compound No. 8.

N.m.r. (CCl4) p.p.m. 1.20-1.40 (m, 6H); 1.80-2.47 (m, 2H): 6.17-6.37 and 6.85-7.43 (mm, 13H).

Product No. 12: 3 - phenoxybenzyl (+) - cisitrans - 3 - (3 - chloro - 3,3 difluoro - 2- chlorodifluoromethylprop - 1 - en - 1 - yl)- 2,2 dimethylcyclopropane carboxylate, is a mixture of 7 parts of compound No. 9 with 13 parts of compound No. 10.

N.m.r. (CCl4) p.p.m. 1.24-142 (m, 6H); 1.76-2.60(m, 2H); 5.02 (s, 2H); 6.16 and 7.12 (dd, 1H); 6.76-7.40 (m, 9H).

Product No. 13: (+) - a - cyano - 3 - phenoxybenzyl (+) - cisitrans - 3 - (3 chloro - 3,3 - difluoro -2 - chlorodifluoromethylprop - 1 - en - I - yl) 2,2 - dimethylcyclopropane carboxylate, is a mixture of 7 parts of compound No. Il with 13 parts of compound No. 12.

N.m.r. (CCl4) p.p.m. 1.24-1.42(m, 6H); 1.84-2.70(m, 2H); 6.16 and 7.12 (dd, 1H); 6.36 (ss, 1H); 6.90-7.50 (m, 9H).

Product No. 14: (+) - a - cyano - 3 - phenoxybenzyl (+) - cisitrans - 3 (Z/E - 3,3 - difluoro - 2 - chlorodifluoromethylprop - I - en - 1 - yl) - 2,2 - dimethylcyclopropane carboxylate, is a mixture of undetermined composition containing compounds 27, 28, 29 and 30.

N.m.r. (CCl4) p.p.m. 1.24-1.52(m, 6H); 1.76-2.70(m, 2H); 5.6-7.6 (m, 12H).

Product No. 15: (1) - a - ethynyl - 3 - phenoxybenzyl (+) - cis/trans - 3 (3,3,3 - trifluoro 2 - trifluoromethylprop - I - en - 1 yl) - 2,2 - dimethylcyclopropane carboxylate, is a mixture of 2 parts of compound No. 13 with 3 parts of compound No. 14.

N.m.r. (CCl4) p.p.m. 1.16-1.44 (m, 6H); 1.76-2.56 (m, 3H); 6.12-7.04 (m, 1H); 6.246.40 (m, 1H); 6.76-7.36 (m, 9H).

EXAMPLE 15 This Example illustrates the insecticidal properties of (1) - a - cyano - 3 phenoxybenzyl (+) - cis/trans - 3 - (3,3,3 - trifluoro - 2 - trifluoromethylprop 1 - en - 1 - yl) - 2,2 - dimethylcyclopropane carboxylate (containing 20 cis - isomer) (Product No. 1) as a representative example of an ester according to the invention.

The activity of the product was tested against a variety of insect and other invertebrate pests. The product was used in the form of liquid preparations, containing 1000, 500, 125 and 62.5 p.p.m. by weight of the product. The preparations were made by dissolving the compound in a mixture of solvents consisting of 4 parts by volume of acetone and 1 part by volume of diacetone alcohol. The solutions were then diluted with water containing 0.01% by weight of a wetting agent sold under the trade name "Lissapol" NX until the liquid preparations contained the required concentration of the compound. "Lissapol" is a Trade Mark.

The test procedure adopted with regard to each pest was basically the same and comprised supporting a number of the pests on a medium which was usually a host plant or a foodstuff on which the pests feed, and treating either or both the pests and the medium with the preparations.

The mortality of the pests was then assessed at periods usually varying from one to three days after the treatment.

The results of the tests are given below in Table II. In the table the first column indicates the name of the pest species. Each of the subsequent columns indicates the host plant or medium on which it was supported, the number of days which were allowed to elapse after the treatment before assessing the mortality of the pests, and the results obtained for each of the concentrations given above. The assessment is expressed in integers which range from 03.

0 represents less than 30% kill 1 represents 30-49% kill 2 represents 50-90% kill 3 represents over 90% kill A dash (-) indicates that no test was carried out. "Contact test" indicates that both the pests and the medium were treated and "residual test" indicates that the medium was treated before infestation with the pests.

TABLE 11

No. Rate of Application (p.p.m.) Support of Pest Species Medium Days 1000 500 125 62.5 Terranychus telarius red adults mites, adults Bean Aphisfabae (black aphids) Broad 2 3 3 3 3 Bean Megoura Viceae (green aphids) Broad 2 3 3 3 3 Bean Aedes aegypti (mosquito adults) Plywood 1 3 3 3 3 Musca domestica (houseflies-- Milk/ 2 3 3 3 3 contact test) Sugar Plutella maculipennis (diamond Mustard 3 3 3 3 3 back moth, larvaeWcontact test Phaedon cochleariae (mustard Grain 3 3 3 3 3 beetle-residual test) Musca domestica (houseflies-- Plywood 3 3 3 3 3 residual test) Calandra granaria (grain beetles Grain 3 3 3 3 residual test) EXAMPLE 16 This Example illustrates the insecticidal properties of the products of Example 14. The tests were conducted under the same conditions as those in Example 15.

The results are given in Table III as the percentage mortality of the pests at one rate of application only for each product.

The symbols used in Table IV have the following meanings.

"P No." indicates "Product No." as defined in Example 14.

"Rate" indicates the concentration expressed in parts per million of the active ingredient in the preparations used in the test.

"A to "M" indicate the pest species used in the tests, which are as follows: "A"-Tetranychus telarius (red spider mites-adults) "B"-Tetranychus telarius (red spider mites-eggs) "C"-Aphis fabae (black aphids) "D"--Megoura viceae (green aphids) "E"-Aedes aegypti (mosquitoes) "F"-Musca domestica (houseflies)-contact activity "G"--Musca domestica (housefliesAresidual activity "H"--Plutella xylostella-residual activity (3 days) "I"-Plutella xylostella-residual activity (10 days) "J"Phaedon cochleariae (mustard beetle) "K"-Calandra granaria (grain beetle) "L"-Tribolium castaneum (flour beetle) "M"-Spodoptora littoralis (cotton leaf worm) An asterisk (*) in the table indicates that in

TABLE Ill

P No. Rate A B C D E F G H I J K L M 1 50 50 40 100 100 80 70 0 0* 80 0* 25 11 2 100 100 90 100 100 100 100 60* 80* 100 60* 100 25 3 100 100 0 100 100 100 100 20 50 70 0 80 36 4 100 90 0 100 100 100 100 100 100 - 40 85 54 5 100 98 0 100 100 100 90 100 100 - 100 69 35 - 6 100 80 0 100 100 100 50 100 80* 100 50* 21 17 - 7 25 50 0 100 100 100 70* 0 20* - 10* 35 0 100 8 25 0 0 90 90 100 40 0 70* - 0* 0 0 100 10 25 20 0 100 100 30 30* - 40* - 0* 0 0 100 11 25 0 0 95 100 20 50* 0 10* - 0* 0 0 100 14 250 0 0 100 100 - 100 - 10 - 20 - - 0 15 50 0 100 100 100 - 56 - 90 - 100 - - 80 EXAMPLE 17 This Example illustrates the ixodicidal activity of product No. 2 against cattle ticks (Boophilus microplus).

A suspension of the product was prepared by ball milling 10 parts of the product with 985 parts of water and 5 parts of "Teric" N9 ("Teric" is a Registered Trade Mark and "Teric" N9 is a nonionic surfactant obtained by condensing nonylphenol with ethylene oxide in a molar ratio of 1:9) to give a composition containing 1.0% active ingredient. A portion of each of the above suspension was then diluted with water to give compositions containing 0.1% and 0.01%, active ingredient.

The efficacy of the product against engorged adult female ticks of the "Yeerongpilly" strain was tested by applying a microdrop of the appropriate concentration suspension to each of about twenty of the ticks. After 14 days the mortality count of the adult ticks was assessed by counting the eggs laid by them and the percentage of those eggs which had hatched. The results are given in Table IV.

The efficacy of the product against larval ticks of the "Yeerongpilly" strain was tested as follows: A sheet of filter paper was soaked in the appropriate concentration suspension and then allowed to dry. The treated paper was converted to the form of an envelope and approximately 100 larval ticks of the "Yeerongpilly" strain were enclosed therein. A mortality count was done on the larval ticks 48 hours after they had been placed in the envelope and the kill rated on a 0--5 scale wherein 0 represents W20% kill 1 represents 2050% kill 2 represents 50-80% kill 3 represents 8095% kill 4 represents 9599% kill 5 represents 100% kill The results are given in Table IV.

In a further test an emulsion of the product was prepared by mixing 25 parts of the compound with 75 parts of cyclohexanone and 25 parts of "Teric" N9 and diluting the mixture with water to provide 10,000 parts by volume of an emulsion.

Each of the emulsions so obtained was sprayed, to drip point, onto calves heavily infested with various stages of the resistant "Biarra" strain of cattle tick. The efficacy of the product was assessed as follows: (i) All adult female ticks which were fully engorged at the time of spraying were collected soon after spraying the calves. They were then placed in a Petri dish in an incubator for assessment of mortality based on capacity to lay eggs, and if eggs were laid, the viability of the eggs as shown by hatch of viable larvae. Engorged adults, if any, were also collected at 24 hours and 48 hours after spraying and the same assessment of mortality was made. This assessment is referred to as "Mortality-Engorged Adults" and the results are given in Table V.

(ii) At daily intervals predetermined sampling areas on each calf were inspected for the effect of the active ingredient on the immature adults and nymphs. This assessment was rated on the 05 scale defined in Example 3 and is referred to as "Mortality-Immature Adults" and "Mortality-Nymphs". The results are given in Table V.

The symbol - is used to indicate that no engorged adults were present.

In these tests permethrin (3 - phenoxybenzyl (+) - cis/trans - 3 - (2,2 dichlorovinyl) - 2,2 - dimethylcyclopropane carboxylate) was used as a standard.

TABLE IV In Vitro Ixodicidal Activity Against Adults and Larvae

% Mortality of Adults Kill Rating Against Larvae Product 1% a.i. 0.1% 1%a.i. 0.1% a.i. 0.01% a.i. 2 100 90 5 5

TABLE V In Vivo Ixodicidal Activity Against Engorged Adults, Immature Adults and Nymphs

Mortality % Active Engorged Adults (%) Immature Product Ingredient 24 hr/24 hr/48 hr Adults* Nymphs* 2 0.05 -/-/- 5 5 2 0.025 -/#- 5 5 2 0.02 -/-/-. 5 4 2 0.01 -/-/- HW 5 5 2 0.005 -/-/- 5 4 2 0.0025 -/-/- 4 3 Permethrin 0.1 -/-/- 5 5 Permethrin 0.05 -/-/- 5 5 Permethrin 0.01 20/60/- 3 1 WHAT WE CLAIM IS:1. A compound of formula:

wherein one of R1 and R2 is a haloalkyl group containing I or 2 carbon atoms, and the other of R1 and R2 is a methyl group or a haloalkyl group containing 1 or 2 carbon atoms, and R is hydroxy, alkoxy containing up to 6 carbon atoms, a halogen atom, a phenoxybenzyloxy group which may optionally be substituted in the a position by cyano or ethynyl.

2. A compound as claimed in Claim 1 in which R is 3 - phenoxybenzyloxy, a cyano - 3 - phenoxybenzyl or a - ethynyl - 3 - phenoxybenzyloxy.

3. A compound of formula:

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (43)

1. **WARNING** start of CLMS field may overlap end of DESC **.

   inspected for the effect of the active ingredient on the immature adults and nymphs. This assessment was rated on the 05 scale defined in Example 3 and is referred to as "Mortality-Immature Adults" and "Mortality-Nymphs". The results are given in Table V.

   The symbol - is used to indicate that no engorged adults were present.

   In these tests permethrin (3 - phenoxybenzyl (+) - cis/trans - 3 - (2,2 dichlorovinyl) - 2,2 - dimethylcyclopropane carboxylate) was used as a standard.

   TABLE IV In Vitro Ixodicidal Activity Against Adults and Larvae

   % Mortality of Adults Kill Rating Against Larvae Product 1% a.i. 0.1% 1%a.i. 0.1% a.i. 0.01% a.i. 2 100 90 5 5

   TABLE V In Vivo Ixodicidal Activity Against Engorged Adults, Immature Adults and Nymphs

   Mortality % Active Engorged Adults (%) Immature Product Ingredient 24 hr/24 hr/48 hr Adults* Nymphs* 2 0.05 -/-/- 5 5 2 0.025 -/#- 5 5 2 0.02 -/-/-. 5 4 2 0.01 -/-/- HW 5 5 2 0.005 -/-/- 5 4 2 0.0025 -/-/- 4 3 Permethrin 0.1 -/-/- 5 5 Permethrin 0.05 -/-/- 5 5 Permethrin 0.01 20/60/- 3 1 WHAT WE CLAIM IS:1. A compound of formula:

   wherein one of R1 and R2 is a haloalkyl group containing I or 2 carbon atoms, and the other of R1 and R2 is a methyl group or a haloalkyl group containing 1 or 2 carbon atoms, and R is hydroxy, alkoxy containing up to 6 carbon atoms, a halogen atom, a phenoxybenzyloxy group which may optionally be substituted in the a position by cyano or ethynyl.
2. 2. A compound as claimed in Claim 1 in which R is 3 - phenoxybenzyloxy, a cyano - 3 - phenoxybenzyl or a - ethynyl - 3 - phenoxybenzyloxy.
3. 3. A compound of formula:

   wherein one of R1 and R2 represents a group of formula: W(CF2)m where W represents an atom of hydrogen, fluorine or chloride and m has the value one or two, and the other of Rl and R2 represents a group of formula:

   where each of X, Y and Z independently represents an atom of hydrogen, fluorine or chlorine, and R3 represents an atom of hydrogen, or the cyano or ethynyl group.
4. 4. A compound as claimed in Claim 3 wherein one of R' and R2 represents a group of formula: WCF2- were W represents an atom of hydrogen, fluorine or chlorine, and the other of R' and R2 represents a group of formula:

   where each of X, Y and Z independently represents an atom of hydrogen, fluorine or chlorine, and R3 represents an atom of hydrogen or the cyano group.
5. 5. A compound as claimed in Claim 4 wherein R' and R2 each represent the trifluoromethyl group.
6. 6. +) - a - Cyano - 3 - phenoxybenzyl (*) - cisltrans - 3 - (3,3,3 - trifluoro 2- trifluoromethylprop - 1 - en - I - yl) - 2,2 - dimethylcyclopropane carboxylate.
7. 7. 3 - Phenoxybenzyl (f)- cisltrans - 3 - (3,3,3 - trifluoro - 2trifluoromethylprop - 1 - en - 1 - yl) - 2,2 - dimethylcyclopropane carboxylate.
8. 8. A compound as claimed in any of Claims I to 5 in which the hydrogen atoms of the cyclopropane ring are in the trans - configuration.
9. 9. A compound as claimed in any of Claims I to 5 in which the hydrogen atoms of the cyclopropane ring are in the cis - configuration.
10. 10. A compound as claimed in any one of the preceding claims in which the absolute configuration of the cyclopropane ring is (1R, 3R) or (IR, 3S).
11. 11. A compound as claimed in any one of claims 3 to 10 in which R3 is not a hydrogen atom in which the absolute configuration of the carbon atom to which R3 is attached is (S).
12. 12. (1) - a - Cyano - 3 - phenoxybenzyl (lR,3R) - 3 - (3,3,3 - trifluoro - 2 trifluoromethylprop - I - en - 1 - yl) - 2,2 - dimethylcyclopropane carboxylate.
13. 13. (S) - a -Cyano -3 -phenoxybenzyl(lR,3R) - 3 -(3,3,3 -trifluoro - 2 - trifluoromethylprop - 1 - en - 1 - yl) - 2,2 - dimethylcyclopropane carboxylate.
14. 14. A process for preparing a compound according to Claim 3 which comprises reacting an acid of formula:

    with an alcohol of formula:

    wherein Rg, R2 and R3 are as defined in Claim 3.
15. 15. A process for preparing a compound according to Claim 3 which comprises reacting an acid halide of formula:

    with an alcohol of formula:

    wherein R', R2 and R3 are as defined in Claim 3 and Q represents a chlorine or bromine atom.
16. 16. A process for preparing a compound according to Claim 3 in which R3 is cyano which comprises reacting an acid halide of formula:

    with a mixture of an alkali metal cyanide and 3-phenoxybenzaldehyde, wherein R1, R2 and Q are as defined in Claim 15.
17. 17. A process for preparing a compound according to Claim 3 which comprises reacting an acid of formula:

    or an alkali metal salt thereof with a halide of formula:

    where Q' represents a halogen atom, and R', R2 and R3 are as defined in Claim 3.
18. 18. A process for preparing a compound according to Claim 3 which comprises heating a lower alkyl ester of formula:

    with an alcohol of formula:

    wherein R', R2, and R3 are as defined in Claim 3 and R4 is a lower alkyl group containing up to six carbon atoms.
19. 19. A process as claimed in Claim 18 carried out in the presence of an alkali metal alkoxide.
20. 20. A process as claimed in Claim 18 carried out in the presence of an alkylated titanium derivative.
21. 21. An insecticidal composition comprising as an active ingredient a compound according to any one of Claims 3 to 13 in association with an insecticidally inert diluent or carrier materials.
22. 22. A composition as claimed in Claim 21 comprising a surface-active agent.
23. 23. A composition as claimed in either of Claims 21 and 22 comprising an insecticide synergist.
24. 24. A method of combating insect or acarine pests at a locus which comprises treating the locus with an insecticidally or acaricidally effective amount of a compound according to any one of Claims 3 to 13 or a composition according to any one of Claims 21 to 23.
25. 25. A method according to Claim 24 wherein the locus is a growing plant or growing plants.
26. 26. A method according to Claim 24 wherein the locus is a domestic animal or domestic animals.
27. 27. A method according to Claim 26 wherein the domestic animals are cattle infested with ixodid ticks.
28. 28. A compound of formula:

    wherein one of R' and R2 represents a group of formula: WCF2)rn where W represents an atom of hydrogen, fluorine or chlorine and m has the value one or two, and the other of R' and R2 represents a group of formula:

    where each of X, Y and Z independently represents an atom of hydrogen, fluorine or chlorine, and Q represents the hydroxy group, a lower alkoxy group containing up to six carbon atoms or the chlorine or bromine atom.
29. 29. A compound as claimed in Claim 28 wherein one of R' and R2 represents a group of formula: WCF2- where W represents an atom of hydrogen, fluorine or chlorine, and the other of R' and R2 represents a group of formula:

    where each of X, Y and Z independently represents an atom of hydrogen, fluorine or chlorine, and Q represents the hydroxy group, a lower alkoxy group containing from one to three carbon atoms, or the chlorine or bromine atom.
30. 30. A compound according to Claim 28 or Claim 29 wherein R' and R2 are both trifluoromethyl groups.
31. 31. (+) - cis/trans - 3 - (3,3,3 - trifluoro - 2 - trifluoromethylprop - I - en 1 - yl) - 2,2 - dimethylcyclopropane carboxylic acid.
32. 32. A compound according to any one of Claims 28 to 31 in the form of its ethyl ester,
33. 33. A process for the preparation of a compound according to Claim 28 in which Q represents a lower alkyl group containing up to six carbon atoms which comprises reacting a diene of formula:

    with a lower alkyl ester of diazoacetic acid.
34. 34. A process as claimed in Claim 33 in which the lower alkyl ester of diazoacetic acid is ethyl diazoacetate.
35. 35. A process as claimed in either of Claims 33 or 34 in which the diene is used in excess.
36. 36. A process as claimed in any of Claims 33 to 35 conducted in the presence of a metallic catalyst.
37. 37. A process for preparing a compound according to Claim 28 in which R' and R2 are both trifluoromethyl or one of R' and R2 is trifluoromethyl and the other is difluoromethyl, and Q is a lower alkyl group containing from one to six carbon atoms, which comprises the steps of (a) treating a compound of formula:

    with a lower alkyl ester of diazoacetic acid, and (b) subjecting the compound of formula:

    thus produced to dehydration with a chemical dehydrating agent.
38. 38. A process as claimed in Claim 37 in which the chemical dehydrating agent is phosphorus pentoxide.
39. 39. A process of preparing a compound according to Claim 28 wherein Q represents a lower alkoxy group containing up to six carbon atoms which comprises treating a compound of formula:

    wherein R' and R2 are as defined in Claim 28 and Q represents a lower alkoxy group containing up to six carbon atoms, and W' and W" each represent fluorine, chlorine or bromine, provided that W' is bromine when R2 is bromine, with at least two molar equivalents of a base.
40. 40. A process as claimed in Claim 39 in which the base is an alkali metal lower alkoxide containing up to six carbon atoms.
41. 41. A process for preparing a compound as claimed in Claim 28 in which a compound according to one of the formulae:

    wherein R, R2, Q, W' and W" are as defined in Claim 39, is treated with at least one mole of a base.
42. 42. Compounds as claimed in Claim 1, and processes for their preparation, substantially as described herein, with particular reference to any one of Examples 12 and 14.
43. 43. Compounds as claimed in Claim 28, and processes for their preparation, substantially as described herein, with particular reference to any one of the Examples 1 to 11 and 13, taken alone or in combination.