GB1592649A

GB1592649A - Imidazoline derivatives and their use as pesticides

Info

Publication number: GB1592649A
Application number: GB53059/76A
Authority: GB
Original assignee: Wellcome Foundation Ltd
Current assignee: Wellcome Foundation Ltd
Priority date: 1976-12-20
Filing date: 1976-12-20
Publication date: 1981-07-08
Also published as: ZA777535B; AU3174677A; ZA777536B; BE862022A; AU520875B2

Description

(54) IMIDAZOLINE DERIVATIVES AND THEIR USE AS PESTICIDES (71) We, THE WELLCOME FOUNDATION LIMITED, of 183-193 Euston Road, London N.W.I a company incorporated in England 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 imidazolines, their preparation and intermediates therefor, pesticidal formulations containing the imidazolines, and to their use as pesticides.

We have discovered that thc compounds of formula (I) below and their acid addition salts have activity against Arthropods, in particular against members of the Order Acarina.

Compounds of formula qj are:

wherein Ar is an unsubstituted or mono-, di- or tri-substituted phenyl radical in which the substituents are the same or different and are selected from alkyl, alkoxy, halogen, hydroxy, cyano, amino, trifiuoromethy! and nitro and in which any two adjacent carbon atoms of the phenyl ring may optionally be joined by a carbon chain having 3 or 4 carbon atoms; Xis O or NH; R' and R2 are the same or different and are hydrogen or alkyl: Z is a group SOnR8 or a group

in which X2 is O, S or NR4; R3 iS alkyl, aryl, alkyloxy, aryloxy or NRsR6; R4 is alkyl, aryl, alkyloxy, aryloxy, alkylthio, arylthio or NR5R6; R5 and R6 are the same or different and are hydrogen, alkyl, aryl, COR7 or SO2R7; R7 is alkyl, aryl, alkyloxy or aryloxy; n is I or 2; R8 is alkyl, aryl or NR9R10; and R9 and R10 are the same or different and are hydrogen, alkyl or aryl; provided that when Ar is unsubstituted phenyl, R and R are H, X is NH, Z is

and X2 is 0, then R3 is not methyl.

In formula (I), halogen includes chloro, bromo, and fluoro and the alkyl and alkoxy groups and moieties each have 1 to 4 carbon atoms. Certain compounds of formula (I) may exist in their solvated forms. The group Ar in formula (I) is preferably unsubstituted or has substituents selected from alkyl (preferably methyl) and/or halogen (preferably chloro) groups.

The term "aryl" as used herein includes phenyl or naphthyl either unsubstituted or substituted with one or more substituents, the substituent(s) being the same or different and preferably selected from alkyl, alkoxy, halogen, nitro, cyano and amino.

Preferred compounds of formula (I) include those wherein: (i) Ar is phenyl or 2,3-dimethylphenyl; and/or (ii) Z is

wherein X2 is O or S and R3 is NR5R6.

Particularly preferred compounds of formula (I) are: 1. N - phenylcarbamoyl - 2 - (2,3 - dimethylphenoxymethyl) - 2 - imidazoline; I-N-(a- - N - (or - Naphthyl)carbamoyl - 2 - (2,3 - dimethyiphenoxymethyl) - 2 - imidazoline; 1 - N - (4 - chlorophenyl)carbamoyl - 2 - (2,3 - dimethylphenoxymethyl) - 2 imidazoline; and - N - (4 - -cyanophenyl)carbarnoyl - 2 - (2,3 - dimethylphenoxymethylj - 2 imidazoline.

The compounds of formula (I) and their acid addition salts have activity against Arthropods, in particular against the Order Acarina. The compounds of formula (I) may be used to control pests such as Rhipicephalus appendiculatus, Boophilus decoloratus, Boophilus microplus, Rhipicephalus evertsi, Amblyomma hebraeum, Psoroptes ovis and Hyaloma species on animals and Tetranychus species on plants.

The compounds of formula (I) may be prepared by any known method for the preparation of compounds of an analogous structure.

In particular the compounds of formula (I) may be prepared from 2-substituted imidazolines of formula (II) or an acid addition salt thereof:

wherein Ar, X1, R' and R2 are as defined above, either by a direct addition reaction with an isocyanate or isothiocyanate (to give a compound of formula (I) where Z is an N-substituted carbamoyl or thiocarbamoyl group); a ketene (to give a compound of formula (I) where Z is an acyl group) or a carbodiimide (to give a compound of formula (I) where Z is an amidino group); or by a substitution reaction with a compound of formula (111): Z--X' (111) where Z is as defined above and X' is a leaving group such as halo (e.g. in acid chlorides or halo-formate esters), acyloxy (e.g. in acid anhydrides), alkoxy or alkylthio (e.g. carbamates, imidate thiocarbamates or thioimidates) or sulphonyloxy (e.g. in mixed anhydrides).

In one particular application of the above substitution reaction, compounds of formula (I) wherein Z is a thiocarbamoyl group may be prepared by the reaction of a compound of formula (II) with a compound of formula (III) wherein Z is a thiocarbamoyl group and Xis NH2 (i.e. Z-X' is a thiourea).

The reaction may be effected optionally in water or an organic solvent, such a chloroform or methylene chloride, preferably in the presence of a base such as an alkali metal hydroxide, an alkali metal carbonate, or a tertiary organic base, such as triethylamine, pyridine or substituted pyridines or piperidines, e.g. pentamethylpiperidine or tetramethylpiperidine; and generally at temperatures of -700C to 1200C, preferably at temperatures of -100C to 400 C.

Compounds of formula (I), in particular those wherein Z is not a strong electron withdrawing group, may be prepared by reacting an ethylenediamine of formula (IV) or salt thereof; H2N. CH2CH2NH.Z (IV) wherein Z is as defined hereinabove, with an appropriate phenoxyalkyl or anilinoalkyl carboxylic acid or a reactive derivative thereof such as imidate, thioimidate, imidohalide, ester, amidine, thioamide, nitrile or carboxyalkylthioamide. These reactants may be conveniently represented by formula (V):

wherein Ar, X1, RX and R2 are as defined hereinabove and Q is a carboxyl group or a reactive derivative thereof which produces the imidazoline ring structure of formula (I) when reacted with a compound of formula (IV): Suitable reactive derivatives include:

OAlk NH y -C-OAlk (orthoester), -C - (imidate), OAlk OAlk NH NH y -C (thioimidate), -C (imido halide), SAlk Hal -O NH y y (ester), -C (amidine), -C (ester), OAlk NH1

S y -C (thioamide), -C=N (nitrile), and NH2 S y (carboxyalkylthioamide) -C NHCO2Alk wherein 'Alk' is an alkyl group having 1 to 6 carbon atoms.

The conditions under which this reaction may be carried out of course depends upon the nature of the starting materials used, and a liquid medium may be present or absent; high and low temperatures may be used, and various pressures employed.

When the carboxylic acid derivative is an imidate, this is preferably in the form of an acid addition salt such as a hydrogen halide salt, and may be prepared from the nitrile and a suitable anhydrous alkanol such as ethanol or methanol in the presence of dry diethyl ether or chloroform and hydrogen chloride at a low temperature. The reaction may be carried out at a temperature in the range of -200C to ambient temperature. The reaction with an ethylenediamine of formula (IV) is preferably conducted in an inert anhydrous medium such as chloroform, methylene chloride or ether. The reactants are preferably heated under reflux until reaction is complete.

The thioimidate intermediates in the form of acid addition salts may be prepared from the corresponding nitrile by reaction with an alkyl mercaptan and a hydrogen halide gas at low temperatures about 0 C, in the presence of dry diethyl ether. The thioimidate may then be reacted with an ethylenediamine of formula (IV) the reaction being effected at the reflux temperature of the reaction mixture.

The ester intermediates may be conveniently prepared from the corresponding acid by known methods, and the acid itself may be prepared from the corresponding nitrile. They may then be reacted with an ethylenediamine of formula (IV), preferably in the presence of a liquid medium which may be polar or non-polar. The reaction is preferably carried out at an elevated temperature.

The compounds of formula (I) may be prepared from the imidohalide intermediates by reaction with an ethylenediamine of formula (IV), under anhydrous conditions in the presence or absence of an acid acceptor and optionally at an elevated temperature. The reaction mixture may include a polar or non-polar liquid medium such as a low alkanol or an ether.

The amidine intermediate in the form of the base or acid addition salts thereof, is preferably converted to a compound of formula (I) by heating under reflux with an ethylenediamine of formula (IV) in the presence of a polar or non-polar liquid medium, for example a lower alkanol, until ammonia ceases to be evolved. The amidine intermediates themselves may be prepared by any knwon method, but conveniently from the corresponding imidates by reaction with ammonia.

The thioamide and amide intermediates may be prepared from the corresponding nitriles or by any other convenient method and may be converted into compounds of formula (I) by heating with an ethylenediamine of formula (IV), at a reflux or higher temperature, in the presence or absence of a polar or nonpolar solvent. Conveniently the reactions are partly effected under reduced pressure to induce the removal of ammonia and/or hydrogen sulphide from the reaction mixture.

The nitrile intermediates are preferably reacted in the presence or absence of a liquid medium with an ethylenediamine of formula (IV) or a salt thereof; the reaction may be carried out in the presence ot hydrogen sulphide. A liquid medium such as a lower alkanol may be included in the reaction mixture which may be heated to reflux temperature, or to a higher temperature in a closed vessel, optionally in the presence of an inert gas such as nitrogen.

It will of course be understood that where the intermediate is the carboxylic acid, the ester or thioamide, there may be isolated as an intermediate the acylethylenediamines of formula (VI):

wherein Ar, X', R', R2 and Z are as defined above and W is oxygen or sulphur and these compounds may themselves be converted in situ to a compound of formula (I), either by separate treatment with a dehydrating agent such as calcium oxide or by continuing the reaction to completion under the original conditions giving rise to a compound of formula (I).

The compounds of formula (I) may be prepared by the reaction of a phenol or amine of formula (VII), or an O- or N-metal compound thereof; Ar-X1-H (VII) wherein Ar and X1 are as defined in formula (I) with a compound of formula (VIII):

wherein R', R2 and Z are as defined in formula (I), and V is a leaving group derived from a suitable inorganic or organic acid. Suitable leaving groups are halo, such as chloro, iodo, or bromo, alkylsulphonyloxy or arylsulphonyloxy such as ptoluenesulphonyloxy.

The compounds of formula (VIII) may be in the form of their bases or acid addition salts thereof. The reaction is carried out in an inert liquid medium which is preferably a polar liquid such as acetonitrile or isopropanol, or may be dimethylsulphoxide, sulpholane, methyl ethyl ketone, dimethylformamide, acetone, dimethylacetamide, N-methyl-2-pyrrolidone, or mixtures of the foregoing.

In the case where V is chloro in a compound of formula (VIII), then a small catalytic quantity of an iodide salt for example sodium iodide, or a phase transfer catalyst such as a quaternary ammonium salt such as benzyltrimethylammonium chloride may advantageously be included in the reaction mixture. The reactants may be heated together under an inert atmosphere such as nitrogen at the reflux temperature of the reaction mixture.

The compounds of formula (I) wherein Z is

and R3 is alkoxy, aryloxy or NR5R6 may also be prepared by reacting a compound of formula (IX):

in which Ar, X', X2, R1 and R2 are as defined above and Y is a leaving group (such as halo, acyloxy, alkoxy, alkylthio, S-, SH, sulphonyloxy or carbalkoxy) with a suitable active hydrogen-containing compound of formula (X): R11-H (X) wherein R" is alkoxy, aryloxy or NR5RB and R5 and R8 are as defined above.

In one particular aspect this method may be applied to the preparation of compounds of formula (I) in which Z is a carbamoyl group by treatment of compound (IX) in which Y is -SR" and X2 is NR4 where R4 is as defined above and R" is an alkyl group with a suitable active-hydrogen containing compound of formula (X) above. The intermediate compounds of formula (IX) in which Y is SR" and X2 is NR4 may be prepared from compounds of general formula (XI):

wherein Ar, X', R', R2 and R" are as defined above.

The compounds of formula (I), wherein Z is

R3 iS as defined above and X2 is NR4 where R4 is as defined in formula (I) above, may also be prepared by reacting a compound of formula (II) above with an imidoyl dihalide of formula (XII): R4-N=(Hal)2 (XII) where R4 is as defined in formula (I) above and Hal is chloro, bromo or iodo, to give an intermediate of formula (IX) above wherein x2 is R4-N and Y is Hal which may then be converted to a compound of formula (I) by the above described method.

The compounds of formula (I) may be isolated from the reaction mixture as the free base or in the form of an acid addition salt. The bases may be converted into acid addition salts thereof by known techniques with the aid of the appropriate acid, and salts of the compound may also be converted into the free bases or into other acid addition salts.

For use as a pesticide, the compounds of formula (I) may be presented in the form of their free bases, or as acid addition salts thereof. Suitable salts of formula (I) include hydrohalide, sulphate, nitrate, phosphate, thiocyanate, acetate, propionate, stearate, naphthenate, perchlorate, benzoate, methanesulphonate, ethanesulphonate, tosylate and benzenesulphonate acid addition salts thereof.

The compound of formula (I) may be used as to combat insects, ticks, mites and other arthropods including free living arthropods and those which are ectoparasites of plants, mammals and birds and may be used alone or in combination with an additive which may take the form of one or more of the carriers used in the formulation art, such as: wetting, diluting, stabilising, thickening, emulsifying, dispersing or surface active agents or other standard carrier ingredients.

A formulation may be an aqueous solution of an acid addition salt of a compound of formula (I), or a suspension of a compound of formula (I) in water, and may be used alone or in combination with suitable surface active agents. The formulation per se may be used alone or diluted in water for application to the pests or their immediate environment by way of spraying or dipping.

A formulation may be in the form of a miscible oil comprising a compound of formula (I) in the form of its free base or with equimolar quantity of a suitable organic acid, such as oleic acid or naphthenic acid, to provide a salt soluble in organic solvents, and emulsifiers, and are-applied as an emulsion by way of spraying or dipping.

A formulation may be a non-aqueous solution or suspension of a compound of formula (I) in a suitable organic solvent for the direct application by the "pour-on" method. A formulation may also take the form of a wettable powder for dilution with water and application by dipping or spraying. Other solid formulations may also be used for direct application without dilution, such as dusts, powders and granules.

A further formulation may be a paste, grease or gel containing a compound of formula (I) and a suitable carrier, and may be applied by spreading the formulation over the infected area.

An acid addition salt or base of a compound of formula (I) is preferably present in a pesticidal formulation in an amount between 5 and 80%, calculated by weight of the base, and particularly preferred formulations containing about 20%, calculated by weight of the base. The concentration of a compound of formula (I) applied to the pests or their immediate environment may be in the range of 0.00l%-20%, calculated by weight of the base.

The following Examples are provided by way of an illustration of the present invention and should not be construed as in anyway constituting a limitation thereof.

Example 1.

Preparation of 2 - (2,3 - dimethylphenoxymethyl) - 1 - acetyl - 2 - imidazoline A solution of acetic anhydride (3.0 ml; 0.032 moles) in diethyl ether (10 ml) was added dropwise, during 10 minutes, to a stirred suspension of 2-(2,3dimethylphenoxymethyl)-2-imidazoline (6.12 g; 0.030 mole) (prepared from 0ethyl-2,3-dimethylphenoxyacetimidate and ethylene diamine) in diethyl ether (100 ml) cooling the mixture to keep its temperature below 20"C. After stirring for 2 hours the reaction mixture was filtered and the precipitate recrystallised from acetone to yield white crystals of 2-(2,3-dimethylphenoxymethyl)- I -acetyl-2- imidazoline, m.p. 127--i300C. Analysis: Calculated C 68.27, H 7.37, N 11.37% Found: C 68.13, H 7.44, N 11.13%.

Example 2.

2 - (2,3 - Dimethylphenoxymethyl) - f - N,N - dimethylthiocarbamoyl - 2 imidazoline A solution of diemthylthiocarbamoyl chloride (2.47 g; 0.020 mole) in chloroform (10 ml) was added dropwise during 10 minutes, to a stirred solution of 2-(2,3-dimethylphenoxymethyl)-2-imidazoline (4.08 g; 0.020 mole) prepared as in Example 1 - and triethylamine (2.0 g; 0.20 mole) in chloroform (50 ml) cooling to keep the reaction below 5"C. The reaction temperature was then allowed to rise to room temperature and finally the reaction was refluxed for 5 hours. After cooling the reaction mixture was washed with water, dried and evaporated. The residue was recrystallised from isopropanol to yield white crystals of 2-(2,3-diemthyl- phenoxymethyl)- 1 -(N,N-dimethylthiocarbamoyl)-2-imidazoline, m.p. 124-1 270C.

Analysis: Calculated C 61.84, H 7.27, N 14.42%. Found: C 62.15, H 7.64, N 14.35%.

Example 3.

2 - (2,3 - Dimethylphenoxymethyl) - 1 - (N - methylthiocarbamoyl) - 2 - imidazoline A solution of methyl isothiocyanate (1.46 g; 0.20 mole) in chloroform (10 ml) was added dropwise during 10 minutes, to a stirred solution of 2-(2,3-dimethylphenoxymethyl)-2-imidazoline (4.08 g; 0.020 moles) prepared as in Example 1 - in chloroform (50 ml) cooling to keep the reaction below 5"C. The reaction mixture was then allowed to warm to room temperature and finally refluxed for 5 hours.

Chloroform was then evaporated in vacuo and the residue recrystallised from isopropanol to yield white crystals of 2-(2,3-dimethylphenoxymethyl)-l-N-methyl- thiocarbamoyl-2-imidazoline, m.p. ca 100 C with decomposition.

1H-NMR (deuterochloroform -- tetramethylsilane internal standard): 8.l-8.3 a 1H Broad singlet 6.8-7.2 a 3H Multiplet 5.0 a 2H Singlet NMR spectra consistent with the proposed structure 3.64.5 a 4H Multiplet 3.1 a 3H Doublet 2.2 a 6H Doublet Example 4.

1 - N - Phenylcarbamoyl - 2 - (2,3 - dimethylanilinomethyl) - 2 - imidazoline 2-(2,3,-Dimethylanilinomethyl)-2-imidazoline(4.20 g; 0.024 moles) was stirred in methylene chloride (90 ml) cooled to 0 C and a solution of phenyl isocyanate (2.84 g; 0.024 moles) in methylene chloride (10 ml) was then added dropwise. A white precipitate formed rapidly. Stirring was continued for 2-3 hours after the addition at OOC, the reaction mixture then allowed to reach ambient tempeature and stirring was continued overnight. The reaction mixture was then evaporated to dryness under reduced pressure and the solid residue so obtained recrystallised from propan-2-ol to yield white crystals of 1-N-phenylcarbamoyl-2-(2,3-dimethylanilinomethyl)-2-imidazoline (0.735H2O) m.p. 1370C.

Example 5.

I - N - (2,3 - Dimethylphenoxycarbonyl) - 2 - (2,3 - dimethylphenoxymethyl) - 2 imidazoline 2-(2,3-Dimethylphenoxymethyl)-2-imidazoline (3.0 g; 0.0147 moles) was dissolved in dry chloroform (~40 ml) and cooled to 0 C. Tetramethylpiperidine (2.07 g; 0.0147 moles) in dry chloroform (~7 ml) was then added to the cooled, stirred solution. 2,3-Dimethylphenylchloroformate (2.71 g; 0.0147 moles as a 30% w/v solution in benzene) was slowly added. A white precipitate formed and stirring was continued at 0 C for 2 hours after which time the reaction mixture was allowed to rise to ambient temperature. Tetramethylpiperidine hydrochloride was precipitated by the addition of dry acetone and removed by filtration. The filtrate was evaporated to dryness under reduced pressure and the white residue recrystallised from propan-2-ol to give 1-N-(2,3,-dimethylphenoxycarbonyl)-2-(2,3-dimethylphenoxymethyl)-2-imidazoline, m.p. 126-127 0C.

Examples 6 to 27.

By methods analogous to those described in Examples 1 to 5 above the compounds of Examples 6 to 27 below are also prepared.

Example 6.

1 - N - Methyloxycarbonyl - 2 - (2,3 - dimethylphenoxymethyl) - 2 - imidazoline, m.p. 120 C.

Example 7.

1 - N - Methylcarbamoyl - 2 - (2,3 - dimethylphenoxymethyl) - 2 - imidazoline, m.p. 147-150 C (dec.).

Example 8.

1 - N - Phenylthiocarbamoyl - 2 - (2,3 - dimethylphenoxymethyl) - 2 - imidazoline, m.p. 102-104 C.

Example 9.

1 - N - 4 - Toluenesulphonylcarbamoyl - 2 - (2,3 - dimethylphenoxymethyl) - 2 imidazoline, m.p. 120 C.

Example 10.

1 - N - (α- Naphthyl)carbamoyl- 2- (2,3- dimethylphenoxymethyl)- 2 imidazoline, m.p. 156-158 C.

Example 11.

1 - N - (4- Chlorophenyl)carbamoyl) - 2 - (2,3 - dimethylphenoxymethyl)- 2 imidazoline, m.p. 132 C.

Example 12.

1 - N - (4 - Cyanophenyl)carbamoyl - 2 - (2,3 - dimethylphenoxymethyl)- 2 imidazoline, m.p. 172-174 C.

Example 13.

1 - N - Phenylcarbamoyl - 2 - phenoxymethyl - 2 - imidazoline, m.p. 170 C.

Example 14.

1 - N,N - Diphenylcarbamoyl - 2 - (2,3 - dimethylphenoxymethyl) - 2 - imidazoline, m.p. 143-145 C.

Example 15.

1 - N - p- Tolylcarbamoyl - 2 - (2,3 - dimethylphenoxymethyl) - 2 - imidazoline, m.p. 137 C.

Example 16.

1 - N - Phenylcarbamoyl - 2 - (α- phenyloxyethyl)- 2 - imidazoline, m.p. 159 C.

Example 17.

1 - N - (α- Naphthyl)carbamoyl - 2 - phenoxymethyl)- 2 - imidazoline, m.p.

160-163 C.

Example 18.

1 - N - Cyclohexylcarbamoyl - 2 - (2,3- dimethylphenoxymethyl)- 2 - imidazoline, m.p. 63 C.

Example 19.

1 - N - Phenylcarbamoyl - 2 - (2 - chloroanilinomethyl) - 2 - imidazoline, m.p.

169 C.

Example 20.

1 - (N - Phenyl - N - methyl)carbamoyl - 2 - (2,3 - dimethylphenoxymethyl) - 2 imidazoline, m.p. 112 C.

Example 21.

1 - N - Phenylcarbamoyl - 2 - (α,α - dimethylphenoxymethyl) - 2 - imidazoline, m.p. 81-85 C.

Example 22.

1 - N - Hexadecylcarbamoyl - 2 - (2,3 - dimethylphenoxymethyl) - 2 - imidazoline, m.p. 76-77 C.

Example 23.

1 - N - (α- Naphthyl)carbamoyl - 2 - (3 - methylanilinomethyl) - 2 - imidazoline, m.p. 146 C.

Example 24.

1 - N - Phenylcarbamoyl - 2 - (2 - chloroanilinomethyl) - 2 - imidazoline, m.p.

168-169 C.

Example 25.

1 - N - (2,6 - Dimethylphenyl)carbamoyl - 2 - (2,3 - dimethylphenoxymethyl)2 - imidazoline perchlorate salt, m.p. 221-222 C.

Example 26.

1 - N - (2,3 - Dichlorophenyl)carbamoyl - 2 - (2,3 - dimethylphenoxymethyl)2 - imidazoline, m.p. 175-180 C.

Example 27.

1 - N - Phenylcarbamoyl - 2 - (3 - methoxyphenoxymethyl) - 2 - imidazoline, m.p. is 101 C.

Example 28.

Preparation of 1- methanesulphonyl- 2- (2,3- dimethylphenoxymethyl)- 2 imidazoline 2-(2,3-Dimethylphenoxymethyl)-2-imidazoline (8.0 g; 0.0392 moles) was dissolved in dry ether (75 ml) and sufficient dry chloroform (50 ml) and the solution cooled in ice (sufficient chloroform was used to prevent precipitation of the imidazoline on cooling). Methanesulphonyl chloride (4.50 g; 0.0393 moles) was added dropwise to the cold, stirred solution. When the addition was complete pentamethylpiperidine (6.08 g; 0.0392 moles was added and the reaction mixture heated under reflux until tic showed that reaction was complete (N3 hrs). The reaction mixture was then concentrated under reduced pressure and the residue extracted with a water/chloroform mixture (1:1; 100 ml). The chloroform layer was washed with water, dried over magnesium sulphate and evaporated under reduced pressure to give a residue which was recrystallised from isopropanol to give l-methanesulphony-2-(2,3-dimethylphenoxymethyl)-2-imidazoline, m.p.

142-1430C.

Example 29.

By a method analogous to that used in Example 28 l-benezenesulphonyl-2 (2,3-dimethylphenoxymethyl)-2-imidazoline, m.p. 108--110"C, was prepared.

Example 30.

Preparation of l-N-phenylcarbamoyl-2-(2,3-dimethylphenoxymethyl)-2- imidazoline (A) A solution of 2-(2,3-dimethylphenoxymethyl)-2-imidazoline (20.4 g; 1.0 moles) in methylene chloride (300 ml) was cooled to 650C and a solution of phenylisocyanate (11.9 g; 1.0 moles) in methylene chloride (300 ml) added dropwise during 30 minutes. The reaction mixture was then allowed to warm to ambient temperature and left to stand for 2 hours, when a precipitate had formed. The reaction mixture was evaporated under reduced pressure and the residue recrystallised from acetone to give 1-N-phenylcarbamoyl-2-(2,3-dimethylphenoxy- methyl)-2-imidazoline, m.p. 150142 C.

B. via the N-Chlorocarbamoyl adduct of 2-(2,3-dimethyl-phenoxymethyl)-2 imidazoline A 17% solution of phosgene in toluene (3.2 g containing 0.5521 g., 0.00549 moles COCl2) in dry chloroform (15 ml) was added slowly with stirring at OOC to a solution of 2-(2,3-dimethylphenoxymethyl)-2-imidazol (2.40 g, 0.0115 moles) in dry chloroform (20 ml). When addition was complete the reaction mixture was left at ambient temperature for 2 hours, diluted with an equal volume of dry diethylether and rapidly filtered. The filtrate, which contained the N chlorocarbamoyl adduct of 2-(2,3-dimethylphenoxymethyl)-2-imidazoline, was treated with freshly distilled dry aniline (0.664 g, 0.00714 moles) and the mixture left at ambient temperature overnight at which time tic showed that the major compound was the desired product. The mixture was evaporated to dryness in vacuo and the residue taken up in a mixture of aqueous sodium carbonate and dichloromethane. The organic layer was washed with water, dried over magnesium sulphate and evaporated to dryness to give a residue which was purified as described in (A) above to give l-N-phenylcarbamoyl-2-(2,3-dimethylphenoxy methyl)-2-imidazoline, identical with that obtained in (A) above.

Example 31.

Engorged female ticks of the Biarra Strain of Boophilus microplus are immersed, in groups of 20 ticks, per concentration in a range of dilutions of the compound under test. The wash is prepared immediately prior to the test by dilution (with water) of the compound under test. The constituents may be in the form of miscible oil or wet

TABLE 1

Compound Example No. IR 90 IR99 1-N-Pheny Icarbamoyl-2-(2,3-dimethy 1- 30 < 0016% 6% phenoxymethyl)-2-imidazoline 1-N-(α-Naphthyl)carbamoyl-2-(2,3- 10 0.0032% 0.0054% dimethylphenoxymethyl)-2 imidazoline 1 -N-Pheny Icarbamoy 1-2-phenoxymethy 1- 13 < 0.2% 2% 2-imidazoline Example 32.

Test compounds were formulated in polyethyleneglycol and injected into ticks at a site just ventral to the mouth parts. After 14 days the percentage inhibition of egg production (IR) was determined. The results are shown in Table 2 below.

TABLE 2

Compound Example No. %IR 1-N-Phenylcarbamoyl-2-(2,3-dimethylphenoxy- 30 40% at 0.1 mg/ml methyl)-2-imidazoline 70% at 1.0 mg/ml l-N-Phenylcarbamoy l-2-phenoxymethy 1-2- 13 100% at 10 mg/ml imidazoline l-N-Pheny Icarbamoy 1-2-(2,3-dimethy lan ilino; 4 50% at 0.1 mg/ml methyl)-2-imidazoline 1-N-(α-Naphthyl)carbamoyl-2-(2,3-dimethyl- 10 40% at 0.1 mg/ml phenoxymethyl)-2-imidazoline 1-N,N-Diphenylcarbamoyl-2-(2,3-dimethyl- 14 70% at 1.0 mg/ml phenoxymethyl)-2-imidazoline 1-N-(4-Chlorophenyl)carbamoyl-2-(2,3-dimethyl- 11 70% at 0.1 mg/ml phenoxymethyl)-2-imidazoline 1-N-(4-Toluenesulphonyl)carbamoyl-2-(2,3- 9 100% at 1.0 mg/ml dimethylphenoxymethyl)-2-imidazoline 1-N-(4-Tolyl)carbamoyl)-2-(2,3-dimethyl- 15 40% at 0.1 mg/ml phenoxymethyl)-2-imidazoline 90% at 1.0 mg/ml 1-N-Methylcarbamoyl-2-(2,3-dimethylphenoxy- 7 80% at 1.0 mg/ml methyl)-2-imidazoline 1-N-(α-Naphthyl)carbamoyl-2-phenoxymethyl- 17 70% at 1.0 mg/ml 2-imidazoline The following formulations are given to illustrate the way in which the pesticidal compounds of the invention can be applied to pests or environments susceptible to pest attack.

FORMULATION 1 Dusting Powders Active Compound 1.0 20.0 parts by wt.

Talc 99.0 80.0 ,, ,, 100.0 100.0 FORMULATION 2 Wettahle Powder Active Compound 25.0 parts by wt.

Sodium Dioctyl Sulphosuccinate 1.0 ,, *Dispersol ACA 2.0 ,, Kaolin 72.0 ,, 100.0 FORMULATION 3 Aqueous Dispersion Active Compound 20.0 parts by wt.

*Keltrol 0.4 " Sodium Dioctyl Sulphosuccinate 0.5 " " " Water 79.1 " 100.0 FORMULATION 4 Pour-On Active Compound 5.0 parts by wt.

Dimethyl Formamide 85.0 " " " Castor Oil 10.0 ,, 100.0 FORMULATION 5 Grease Active Compound 6.0 parts by wt.

Petroleum Jelly 94.0 " " " 100.0 FORMULATION 6 Miscible Oil Compound from Example 22 10.0 parts by wt.

*Aromasol H 70.0 " Nonyl Phenol Ethoxylate 20.0 ,, 100.0 *"Dispersol", "Keltrol" and "Aromasol" are Registered Trade Marks

Claims

WHAT WE CLAIM IS:- 1. A compound of formula (I):

wherein Ar is an unsubstituted or mono-, di or tri-substituted phenyl radical in which the substituents are the same or different and are selected from alkyl, alkoxy, halogen, hydroxy, cyano, amino, trifluoromethyl and nitro and in which any two adjacent carbon atoms of the phenyl ring may optionally be joined by a carbon chain having 3 or 4 carbon atoms; X' is O or NH; R' and R2 are the same or different and are hydrogen or alkyl; Z is a group SOnR8 or a group

in which x2 is O, S or NR4; R3 is alkyl, aryl, alkyloxy, aryloxy or NR5Rs R4 is alkyl, aryl, alkyloxy, aryloxy, alkylthio,' arylthio or NR5R6; R5 and RB are the same or different and are hydrogen, alkyl, aryl, COR7 or SO2R7; R7 is alkyl, aryl, alkyloxy or aryloxy; n is 1 or 2; R8 is alkyl, aryl or NR9R'0, and R9 and R10 -are the same or different and are hydrogen, alkyl or aryl; provided that when Ar is unsubstituted phenyl, R' and R2 are H, X' is NH, Z is

and X2 is 0,- then R3 is not methyl, or an acid addition salt thereof.
2. A compound as claimed in claim 1 wherein Ar is unsubstituted phenyl or substituted phenyl having one or more substituents which are the same or different and are alkyl or halogen;
3. A compound as claimed in either claim I or claim 2 wherein Ar is substituted phenyl having one or more substituents which are the same or different and are alkyl or halogen.
4. A compound as claimed in any one of claims 1 to 3 in which Ar is substituted phenyl wherein the substituents are selected from methyl and chloro.
5. A compound as claimed in any one of claims 1 to 4 wherein Ar is disubstituted phenyl.
6. A compound as claimed in any one of claims 1 to 5 wherein Ar .s 2,3dimethylphenyl.
7. A compound as claimed in any one of claims 1 to 6 wherein Z is a group

where X2 and R3 are as defined in claim 1.
8. A compound as claimed in any one of claims I to 7 wherein Z is a group

where R5 and R8 are as defined in claim 1.
9. A compound as claimed in any one of claims 1 to 7 wherein Z is

where R5 and R6 are as defined in claim 1.
10. A compound as claimed in claim 8 or claim 9 wherein R5 is hydrogen and R6 is aryl.
11. A compound as claimed in claim 10 wherein Re is phenyl, 4-chlorophenyl, 4-cyanophenyl or a-naphthyl.
12.1 - N- Phenylcarbamoyl- 2- (2,3- dimethylphenoxymethyl)- 2- imidazoline or an acid addition salt thereof.
13. 1 - N- (a - Naphthyl)carbamoyl- 2 - (2,3 - dimethylphenoxymethyl) - 2 imidazoline or an acid addition salt thereof
14. 1 - N- (4 - Chlorophenyl)carbamoyl - 2 - (2,3 - dimethylphenoxymethyl) - 2 imidazoline or an acid addition salt thereof.
15. 1 - N- (4 - Cyanophenyl)carbamoyl - 2 - (2,3 - dimethylphenoxymethyl) - 2 imidazoline or an acid addition salt thereof.
16. A process for preparing a compound of formula (I) as claimed in claim 1 or an acid addition salt thereof which comprises: (a) reacting a compound of formula (II):

wherein Ar, X', R' and R2 are as defined in claim I with an isocyanate, isothiocyanate, ketene, carbodiimide or a compound Z-X' where Z is as defined in claim 1 and X' is a leaving group; (b) reacting a compound of formula (V):

wherein Ar, X', R' and R2 are as defined in claim 1 and Q is a carboxyl group or a reactive derivative thereof with an ethylenediamine of formula (IV): H2N.CH2CH2.NHZ where Z is as defined in claim 1; or (c) cyclisation of a compound of formula (VI):

wherein Ar, X', R1, R2 and Z are as defined in claim I and W is oxygen or sulphur; (d) reacting a compound of formula (VII) or an N- or 0- metal salt thereof; Ar-X'-H (VII) wherein Ar and X' are as defined in claim 1 with a compound of formula (VIII):

wherein R', R2 and Z ard as defined in claim I and V is a leaving group derived from a suitable inorganic or organic acid; or (e) when Z in formula (I) is

and R3 is alkoxy, aryloxy or NR5R6 reacting a compound of formula (IX):

wherein Ar, X', X2, R1 and R2 are as defined in formula (I) and Y is a leaving group with a compound of formula (X): R"H (X) wherein R" is alkoxy, aryloxy or NR5R6 where R5 and R6 are as defined in claim 1.
17. A process as claimed in claim 16(a) wherein the reaction is effected in water or an organic solvent.
18. A process as claimed in either claim 16(a) or claim 17 wherein the reaction is effected in the presence of a base selected from an alkali metal hydroxide, an alkali metal carbonate or a tertiary organic base.
19. A process as claimed in claim 16(b) wherein Q in formula (V) is selected from an imidate, ortho-ester, thioimidate, imidohalide, ester, amidine, thioamide, nitrile, carboxyalkylthioamide or carboxyl group.
20. A process as claimed in claim 16(c) wherein the compound of formula (VI) is obtained from a compound of formula (V) as defined in claim 16(b).
21. A process as claimed in claim 16(d) wherein in the compound of formula (VIII) V is selected from chloro, iodo, bromo, alkylsulphonyloxy or arylsulphonyloxy.
22. A process as claimed in claim 16(e) wherein in the compound of formula (IX) Y is halo, acyloxy, alkoxy, alkylthio, S-, SH, sulphonyloxy or carbalkoxy.
23. A process as claimed in claim 16(e) or claim 22 wherein in the compound of formula (IX), Y is SR" and x2 is NR4 where R" is an alkyl group and R4 is as defined in claim I and the compound of formula (IX) is obtained from a compound of formula (XI):

wherein Ar, X', R' and R2 are as defined in claim 1 and R" is an alkyl group.
24. A process as claimed in either claim 16(e) or claim 22 wherein in the compound of formula (IX) x2 is R4N where R4 is as defined in claim 1 and Y is Hal where Hal is halogen and wherein the compound of formula (IX) is obtained by reaction of a compound of formula (II) as defined in claim 16(a) with a compound of formula (XII): R4-N=C(Hal)2 (XII) where R4 and Hal are as defined hereinabove.
25. A pesticidal formulation comprising, as active iilgredient, a compound of formula (I) as claimed in claim 1 or an acid addition salt thereof together with a carrier therefor.
26. A pesticidal formulation as claimed in claim 25 wherein the active ingredient is present in an amount of from 5 to 80%, calculated by weight of the base.
27. A pesticidal formulation as claimed in either claim 25 or claim 26 wherein the active ingredient is present in an amount of about 20%, calculated by weight of the base.
28. A pesticidal formulation as claimed in any one of claims 25 to 27 in the form of a wettable powder.
29. A pesticidal formulation as claimed in any one of claims 25 to 28 wherein the active ingredient is 1- N- phenylcarbamoyl- 2- (2,3- dimethylphenoxy methyl) - 2- imidazoline or an acid addition salt thereof.
30. A pesticidal formulation as claimed in any of claims 25 to 28 wherein the active ingredient is 1- N- (a - naphthyl)carbamoyl- 2- (2,3- dimethylphenoxy methyl) - 2- imidazoline or an acid addition salt thereof.
31. A pesticidal formulation as claimed in any one of claims 25 to 28 wherein the active ingredient is 1- N- (4- chlorophenyl)carbamoyl - 2 - (2,3 - dimethylphenoxymethyl)- 2- imidazoline or an acid addition salt thereof.
32. A pesticidal formulation as claimed in any one of claims 25 to 28 wherein the active ingredient is 1- N- (4- cyanophenyl)carbamoyl - 2 - (2,3 - dimethylphenoxymethyl)- 2- imidazoline or an acid addition salt thereof.
33. A method for preparing a formulation as defined in any one of claims 25 to 32 which comprises bringing the active ingredient into association with the carrier therefor.
34. A method of controlling arthropod pests which comprises applying to the pest or the pest's environment a compound of formula (I) as defined in any one of claims 1 to 15.
35. A method as claimed in claim 34 wherein the compound is applied at a concentration of 0.001% to 20%, calculated by weight of the base.
36. A method as claimed in either claim 34 or 35 wherein the pest is a member of the order Acarina.
37. A compound as claimed in any one of claims I to 15 and substantially as hereinbefore described with reference to the Examples.
38. A process as claimed in any one of claims 16 to 24 and substantially as hereinbefore described with reference to Examples 1 to 30.
39. A compound as claimed in claim I whenever prepared by a process as claimed in any one of claims 16 to 24 or 38.
40. A pesticidal formulation as claimed in any one of claims 25 to 32 and substantiallv as hereinbefore defined with reference to Formulations I to 6.
41. A method for preparing a pesticidal formulation as claimed in'claim 33 and substantially as hereinbefore described.
42. A pesticidal formulation as claimed in claim 25 whenever prepared by the method of claim 33 or claim 41.
43. A method of controlling arthropod pests as claimed in any one of claims 34 to 36 and substantially as hereinbefore defined.