GB1576646A

GB1576646A - Derivatives of amidoximes

Info

Publication number: GB1576646A
Application number: GB21684/78A
Authority: GB
Original assignee: Philagro SA
Current assignee: Bayer CropScience SA
Priority date: 1977-07-28
Filing date: 1978-05-23
Publication date: 1980-10-15
Also published as: JPS5427558A; HU180918B; DE2831983A1; CH634067A5; ATA552178A; FR2398744A2; PL208678A1; IT1112650B; PL112882B1; IT7826286A0; AT365586B; DD137181A5; LU80050A1; IE47162B1; IE781511L; FR2398744B2; SE7808241L; DK334578A; BE869383R; NL7807969A

Abstract

The derivatives of the formula <IMAGE> in which: R represents a hydrogen atom or an alkyl radical containing from 1 to 4 carbon atoms, A represents a cyano group or a radical of formula <IMAGE> in which R1 and R2, which are identical or different, each represent a hydrogen atom, an alkyl radical containing from 1 to 4 carbon atoms, an optionally substituted phenyl radical or an amino radical which is itself optionally substituted, can be used in agriculture as phytohormones and herbicides.

Description

(54) NEW DERIVATIVES OF AMIDOXIMES (71) We, PHILAGRO, a French body corporate of 14.20 Rue Pierre Baizet, Lyon 9e, France, 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 derivatives of amidoximes, to processes for their preparation and to compositions containing them. It is a modification of the invention described and claimed in our United Kingdom Patent No. 1501529.

In United Kingdom Patent No. 1501529 we have claimed derivatives of amidoximes of the general formula:

[wherein R represents a hydrogen atom or an alkyl radical containing 1 to 4 carbon atoms, or a phenyl radical; R1 represents a hydrogen atom or an alkyl radical containing 1 to 4 carbon atoms, or a monovalent metal atom, e.g. sodium; and Ar represents a phenyl radical substituted by 1, 2 or 3 substituents, which - when two or three substituents are present - may be identical or different, selected from halogen atoms, the hydroxy radical, alkyl radicals containing 1 to 4 carbon atoms, alkoxy radicals containing 1 to 4 carbon atoms, alkylthio radicals containing 1 to 4 carbon atoms, alkylsulphinyl radicals containing 1 to 4 carbon atoms, alkylsulphonyl radicals containing 1 to 4 carbon atoms, the trifluoromethyl, trifluoromethoxy, trifluoromethylthio and carboxy radicals, alkoxycarbonyl radicals containing 2 to 5 carbon atoms, the nitro and amino radicals, alkylamino radicals containing 1 to 4 carbon atoms in the alkyl group, dialkylamino radicals containing 1 to 4 carbon atoms in each alkyl group, acylamino radicals containing 1 to 4 carbon atoms in the acyl (preferably alkanoyl)moiety, alkoxycarbonylamino radicals containing 1 to 4 carbon atoms in the alkoxy group, the azido radical, alkanoyl radicals containing 1 to 4 carbon atoms, the sulphamoyl radical optionally substituted on the nitrogen atom by one or two alkyl groups, the alkyl group(s) containing 1 to 4 carbon atoms, or the phenyl radical, or Ar represents a mononuclear aromatic heterocyclic radical with 5 atoms in the ring, the hetero atom being oxygen, sulphur or nitrogen (preferably thienyl, pyrrolyl or furyl), said heterocyclic radical being unsubstituted or substituted by a halogen atom, an alkyl radical containing 1 to 4 carbon atoms, an alkoxy radical containing 1 to 4 carbon atoms, an alkylthio radical containing 1 to 4 carbon atoms, or an unsubstituted or substituted phenylalkyl radical containing 1 to 4 carbon atoms in the alkyl moiety, e.g. benzyl] which possess phytohormonal and herbicidal properties.

As a result of further research and experimentation, it has been found that certain derivatives of these compounds of general formula I wherein Ar represents the thienyl radical also possess similar properties useful in the agricultural field.

The amidoxime derivatives of the present invention are those of the general formula:

wherein R2 represents a hydrogen atom or an alkyl radical containing from 1 to 4 carbon atoms and A represents the cyano radical or a group of the general formula:

wherein R3 and R4 are the same or different and each represents a hydrogen atom, an alkyl radical containing from 1 to 4 carbon atoms, an optionally substituted phenyl radical, for example a phenyl radical carrying one or two substituents selected from halogen atoms and alkyl radicals containing from 1 to 4 carbon atoms, or an amino radical which is optionally substituted by, for example, one or two radicals selected from alkyl radicals containing from 1 to 4 carbon atoms and the phenyl radical.

When R2 represents an alkyl radical, the compounds of general formula II exist in two optically isomeric forms and such forms and mixtures thereof are included within the scope of the present invention.

Preferred amidoxime derivatives of the present invention are those of the general formula:

wherein B represents the cyano radical or a group of the general formula:

wherein R5 and R6 are the same or different and each represents a hydrogen atom, an alkyl radical containing from 1 to 4 carbon atoms, the pheny radical, or an amino radical which is optionally substituted by one or two radicals selected from alkyl radicals containing from 1 to 4 carbon atoms and the phenyl radical. Of particular interest are O-(carbamoylmethyl)thiophene-2-carboxamidoxime. O-(hydrazinocarbonylmethyl)- thiophene-2carboxamidoxime. O-(N.N-dimethylcarbamoylmethyl)- thiophene-2-carboxamidoxime, O-(N- methylcarbamoylmethyl)- thiophene-2-carboxamidoxime, O-[(2-phenylhydrazino) carbonylmethyl]-thiophene- 2-carboxamidoxime. O-(anilinocarbonylmethyl)- thiophene2-carboxamidoxime. O-(N.N-dimethylhydrazinocarbonylmethyl)- thiophene-2carboxamidoxime and O-(cyanomethyl)-thiophene- 2-carboxamidoxime.

As mentioned heretofore the amidoxime derivatives of general formula II possess properties useful in the agricultural field.

When they are used as doses of between 0.1 and 100 g/hl of water, they exhibit phytohormonal properties which are similar to those of indolylacetic acid and derivatives of the phenoxyacetic acids. They are particularly useful in assisting the setting of fruit on certain plants (e.g. tomatoes), preventing the shedding of leaves or fruit, our increasing the formation of roots.

When they are used at rates of application of between 0.5 and 10 kg/ha, the amidoxime derivatives of general formula II exhibit herbicidal properties, in particular against dicotyledon plants, both in pre-emergence and post-emergence application.

According to a feature of the present invention, the amidoxime derivatives of general formula II wherein A represents a group of general formula III are prepared by reacting ammonia or an amine of the general formula HNR3R4 (wherein R3 and R4 are as hereinbefore defined) with a compound of the general formula:

wherein R2 is as hereinbefore defined and X represents either a group -CO-0-R7 in which R7 represents an alkyl radical containing from 1 to 4 carbon atoms, or a group -COC1, optionally in the form of the hydrochloride.

Whex X represents a group -CO-O-R7, the reaction is preferably carried out at a temperature between 15G and 100"C, optionally under pressure, and either in an organic or aqueous-organic solvent medium (for example, in an alcoholic or an aqueous-alcoholic solution), or in the absence of a solvent when the reactants are liquid under the reaction conditions employed.

The preparation of compounds of general formula VI wherein X represents a group -CO-O-R7 has been described in our United Kingdom Patent Specification No. 150/529.

When X represents a group -COC1, the reaction is preferably carried out by reacting the hydrochloride of a compound of general formula VI with a compound of the general formula NHR3R4 (wherein R3 and R4 are as hereinbefore defined) at a temperature between 15 and 50"C and either in an inert solvent medium or in the absence of solvent when the reactants are liquid under the reaction conditions employed.

The compounds of general formula VI wherein X represents a group -COC1 can be obtained in accordance with known methods for preparing acid chlorides from the corresponding acids, the preparation of which has been described in our United Kingdom Patent Specification No. 1501529.

According to a further feature of the present invention, those amidoximes of general formula II wherein A represents the cyano radical are prepared by the process which comprises reacting an amidoxime of the general formula:

with a halogenonitrile of the general formula:

(wherein R2 is as hereinbefore defined and Y represents a halogen, preferably chlorine, atom) in the presence of an alkaline condensation agent such as a quaternary ammonium hydroxide (e.g. tetraethylammonium hydroxide), sodium hydroxide, or potassium hydrox ide, in an aqueous-organic solvent medium (for example, a mixture of dimethylformamide and water) at a temperature of from 15 to 800C.

The following Examples illustrate the preparation of amidoxime derivatives of general formula II by processes hereinbefore described.

EXAMPLE I Preparation of O-(carbamoylmethyl) -thiophene-2-carboxamidoxime (compound 1) A solution of 0-(ethoxycarbonylmethyl) -thiophene-2-carboxamidoxime (20 g), prepared as described in Example 1 of Patent Specification No. 1501529, in methanol (200 cc) is saturated with ammonia, whilst keeping the mixture at a temperature less than 40 C.

Thereafter, the mixture is stirred for 16 hours and the solvent is then distilled off under reduced pressure (20 mm Hg) at a temperature of about 35 C. The residue is taken up with water (100 cc) and the crystals obtained are filtered off, washed with water (3 x 50 cc) and dried at a temperature of about 40 C. O-(Carbamoylmethyl) -thiophene-2-carboxamidoxime (11 g), melting at 199 C, is thus obtained. After recrystallisation from acetonitrile, the pure product melts at 199 C.

EXAMPLE 2 Preparation of O-(hydrazinocarbonylmethyl)-thiophene-2-carboxamidoxime (compound 2) A solution of (200 cc) is added dropwise, during the course of 50 minutes, to hydrazine hydrate (200 cc), heated to 95 C, and the reaction mixture is then kept at a temperature between 85 and 95 C for 1 hour. The mixture is then concentrated under reduced pressure (20 mm Hg and then 1 mm Hg) at a temperature of about 60 C in order to drive off the ethanol and the major part of the hydrazine hydrate; the residue is taken up with water (200 cc) and the crystals are filtered off and washed with water (3 x 50 cc).

After standing for 16 hours, the mother liquors provide a second crop of white crystals which are collected by filtration and washed with water (2 x 10 cc).

The two crops of crystals are combined and dried together. O-(Hydrazinocarbonylmethyl) -thiophene-2-carboxamidoxime (10 g) is thus obtained. After recrystallisation from acetonitrile (20 cc), the product melts at 1560C.

EXAMPLE 3 By following the same procedure as described in Example 2, using appropriate starting materials, the following compounds were prepared: No. of m.p.

Compound Compound Yield ( C) 3 O-(N,N-dimethylcarbamoylmethyl)- 49.5% 120 thiophene-2-carboxamidoxime 4 O-(N-methylcarbamoylmethyl)- 64.0% 153 thiophene-2-carboxamidoxime 5 0-[(2-phenylhydrazino)carbonylmethyl]- 49.5% 169 thlophene-2-carboxamidoxime EXAMPLE 4 Preparation of O-(anlinocarbonylmethyl) -thiophene-2-carboxamidoxime (compound 6) O-(Chloroformylmethyl)-thiophene -2-carboxamidoxime hydrochloride (10.2 g) is added in small portions to aniline (30 cc) and the reaction mixture is allowed to stand for several hours. Diethyl ether (150 cc) is then added and the precipitate of aniline hydrochloride is filtered off and washed with diethyl ether (2 x 50 cc). The filtrate is concentrated under reduced pressure (20 mm Hg) at a temperature of about 30 C, and then under a pressure of 1 mm Hg at a temperature of 90 C. O-(Anilinocarbonylmethyl)-thiophene -2-carboxamidoxime (10.9 g) is thus obtained in the form of an oil which slowly solidifies.

After recrystallisation from acctonitrile (20 cc), the pure product melts at 123 C.

EXAMPLE 5 By following the procedure of Example 4, using appropriate starting materials, 0 (N,N-dimethyffiydrazinocarbonylmethyl)-thiophene-2 -carboxamidoxime (compound 7) was prepared in 40% yield. It melted at 1390C.

EXAMPLE 6 Preparation of O-(cyanomethyl)-thiophene -2-carboxamidoxime (compound 8) Thiophene-2-carboxamidoxime (14.2 g) is added to an aqueous solution (84.2 cc) containing 17.5%of tetraethylammonium hydroxide. After 5 hours at a temperature of about 20"C, the water is evaporated under reduced pressure (1 mm Hg) at a temperature of about 25"C and the residue obtained is then redissolved in dimethylformamide (100 cc). The solution is cooled to a temperature of about 5"C, chloroacetonitrile (11.3 g) is run in and the mixture is allowed to return to a temperature of about 20"C. After 26 hours, dimethylformamide (about 70 cc) is distilled off under reduced pressure (1 mm Hg) at a temperature of about 25"C and water (100 cc) is then added. After stirring of the mixture for 2 hours, the resulting crystals are filtered off, washed with water (3 x 20 cc) and dried. These crystals are dissolved in ethyl acetate (150 cc), decolourised with animal charcoal and dried over calcined magnesium sulphate. After filtering and evaporating the solvent, O-(cyanomethyl)- thiophene2-carboxamidoxime (10.1 g), melting at 960C, is obtained. After recrystallisation from methanol, the pure crystals melt at 96"C.

The phytohormonal activity of the amidoxime derivatives of general formula II is demonstrated in the following experiments.

A condensation product (10 parts) of ethylene oxide with octylphenol, having 10 molecules of ethylene oxide per molecule of octylphenol, is added to a solution of the active compound to be tested (25 parts) in a mixture (65 parts) of equal parts of toluene and acetophenone. The solution is used after dilution with water to the desired concentration hereafter mentioned.

(1) Propagation of tomato leaves The second and third leaves are removed from tomato stems (Marmande variety) having 5 or 6 leaves. The petiole of each leaf is dipped over a length of 2 to 3 cm into the solution to be studied which is contained in a test tube. Eight days after the start of the experiment, the percentage of rooted leaves and the mean number of roots per rooted leaf are evaluated.

Concentration of Percentage Mean number of roots active material of rooted per rooted leaf mg/litre leaves Control 0 50 5 Compound 0.01 100 10 1 0.1 100 20 Compound 0.01 100 15 2 0.1 100 15 Compound 0.01 50 5 5 0.1 100 8 Compound 0.01 100 45 8 0.1 85 8 (2) Setting of fru it of tomatoes The solutions to be studied are sprayed onto the first and second flower trusses of tomato stems (Marmande variety) when 2 or 3 flowers of each truss are on the point of opening.

Before the treatment, the number of flower buds on each truss is counted. All the other trusses which subsequently form on the treated plants are removed as they appear. One month after the treatment, the number of fruits which have formed is counted and compared with the results obtained on control plants treated with an aqueous solution containing the same wetting agent.

Total number of fruits Concentration x 100 in g/hl Number of treated flowers Control 0 30 Compound 1 3 80 Compound 2 3 80 Compound 3 3 40 The herbicidal activity of the amidoxime derivatives of general formula II is demonstrated in the following experiment.

A solution or dispersion of the active compound having the following composition is used: active compound to be tested 400 mg acetone (solvent) 5 ml sorbitol monooleate oxyethyleneated with 20 molecules of ethylene oxide (wetting agent) 50 mg distilled water containg 0.1% of the product resulting from the condensation of 10 molecules of ethylene oxide with one molecule of ocylphenol q.s.p. 40 ml.

This solution or dispersion is then diluted with distilled water in order to obtain the desired concentration.

Seeds of various species, namely wheat (Triticum sativum), lentil (Lens culinaris), radish (Raphanus sativus), sugar beet (Beta vulgaris) and slender foxtail (Alopecurus agrestis), are sown in plastic pots (180 cc capacity) containing to a height of 6 cm a mixture composed of 1/3 of clean earth, 1/3 of vegetable mould and 1/3 of river sand, at a rate of about 30 seeds per pot. Two pots of wheat and four pots of the other species are used for each concentration of product.

For the purpose of a post-emergence treatment, the sowing is carried out in a greenhouse one week before the start of the experiment so that the small plants are at the following stage at the time of treatment: wheat and foxtail : 3 leaves lentils : 3 leaves beet and radish : 2 well-developed cotyledon leaves.

The treatment is carried out by spraying the solution or suspension of the product, the pots being placed on a pot-turner. Each pot is given 1 cc of the solution. The doses of the product to be studied are 1 and 8 kg/ha.

In pre-emergence testing, the seeded surface of the pots is allowed to dry and then covered to a depth of 1 cm with the same earth mixture. The pots are watered twice a day by sprinkling.

In post-emergence testing, the treated small plants are allowed to dry. The earth mixture is moistened by placing the base of the pots in a tray containing water.

In both cases, the pots are kept in a greenhouse (22 to 24"C, 70 to 80% relative humidity) under artificial light which provides 5,000 to 6,000 Lux at the level of the plants, for 17 consecutive hours per day.

Three weeks after the start of the treatment, the number of small plants in each pot is counted and their height is measured.

The results are expressed in percentage destruction relative to the control plants.

The results are summarised in the Table which follows. Percentages equal to 0 and 100% indicate that there is respectively complete selectivity and complete destruction of the species in question.

Pre-emergence Post-emergence No. of Dose Compound Kg/ha Wheat Lentil Radish Beet Foxtail Wheat Lentil Radish Beet Foxtail 1 1 30 100 40 50 50 0 60 0 0 0 8 70 100 100 100 75 0 100 60 25 25 2 1 30 100 60 50 75 0 50 0 0 0 8 70 100 100 90 100 0 100 60 25 25 3 1 0 0 0 0 0 0 0 0 0 0 8 30 100 0 50 80 0 0 0 0 0 5 1 30 100 0 80 75 0 0 0 0 50 8 50 100 100 100 90 0 70 100 70 50 6 1 20 100 30 100 50 0 0 0 0 0 8 60 100 100 100 100 0 70 20 100 25 7 1 20 100 30 80 50 0 0 0 0 0 8 30 100 100 100 75 0 70 0 0 0 8 1 20 100 80 80 75 0 100 20 0 20 8 75 100 100 100 100 0 100 30 0 40 For practical application the amidoxime derivatives of general formula II are rarely employed by themselves, but instead are generally employed in association with at least one carrier and/or a surface-active agent compatible with the active material and suitable for use in agricultural or horticultural compositions. In such compositions, which are a feature of the present invention, the content of active compound can be from 0.005 to 95% by weight according to the form of presentation.

The term "carrier" in the sense of the present description denotes an organic or inorganic, natural or synthetic, material with which the active compound is associated in order to facilitate its application to the plant, to seeds or to the soil, or to facilitate its transportation, or its handling. The carrier can be solid (e.g. clays, natural or synthetic silicates, resins, waxes and solid fertilisers) or fluid (e.g. water, alcohols, ketones, petroleum fractions, chlorinated hydrocarbons or liquefied gases).

The surface-active agent can be an emulsifying agent, a dispersing agent or wetting agent, which can be ionic or non-ionic, for example, salts of polyacrylic acids and of ligninsulphonic acids, and condensates of ethylene oxide with fatty alcohols, fatty acids or fatty amines, and especially products based on condensates of ethylene oxide such as the condensates of ethylene oxide with octylphenol or nonylphenol.

The compositions according to the invention can be prepared in the form of wettable powders, dusting powders, granules, solutions, suspensions, emulsifiable concentrates, emulsions, suspension concentrates and aerosols.

The wettable powders are usually prepared in such a way that they contain from 20 to 95 % by weight of active compound; they usually contain, in addition to a solid carrier, from 0 to 5% by weight of wetting agent, from 3 to 10% by weight of a dispersing agent and, where necessary, from 0 to 10%by weight of one or more stabilisers and/or other adjuvants such as penetrating agents, adhesives of anticaking agents and dyestuffs.

By way of example, the composition of a wettable powder is given below, the percentages being expressed by weight.

EXAMPLE 7 Compound 1 (as hereinbefore identified) 50% calcium lignosulphonate (deflocculant) 5% isopropyl naphthalenesulphonate (wetting agent) 1% silica anti-caking agent 5% kaolin filler 39% The powders for dusting are usually prepared in the form of a dust concentrate having a composition similar to that of a wettable powder but without dispersing agent; they can be diluted on site by means of a supplementary amount of a solid carrier so that a composition which usually contains from 0.5 to 10% by weight of active compound is obtained.

The emulsifiable concentrates which can be applied by spraying usually contain, in addition to the solvent and, where necessary, a co-solvent, from 10 to 50%(w/v) of active compound, from 2 to 20%(w/v) of emulsifiers and from 0 to 20%(w/v) of appropriate additives, such as stabilisers, penetrating agents, corrosion inhibitors, dyestuffs and adhesives.

By way of example, the composition of an emulsifiable concentrate is given below.

EXAMPLE 8 Compound 2 (as hereinbefore identified) 400 g/l dodecylbenzenesulphonate 24 g/l nonylphenol oxyethylenated with 10 molecules of ethylene oxide 16 g/l cyclohexanone 200 g/l aromatic solvent q.s.p. 1 litre.

The suspension concentrates, which can also be applied by spraying, are prepared in such a way that a stable fluid product which does not sediment is obtained. They usually contain from 10 to 75% by weight of active compound, from 0.5 to 15% by weight of surface-active agents, from 0.1 to 10% by weight of anti-sedimentation agents such as protective colloids and thixotropic agents, from 0 to 10% by weight of appropriate additives, such as anti-foam agents, corrosion inhibitors, stabilisers, penetrating agents and adhesives and, as the carrier, water or an organic liquid in which the active material is substantially insoluble; certain organic solid materials or inorganic salts can be dissolved in the carrier to assist in preventing the sedimentation or to act as anti-freeze agents for the water.

Aqueous dispersions and emulsions, for example compositions obtained by diluting a wettable powder or an emulsifiable concentrate according to the invention with water, also fall within the general scope of the present invention. These emulsions can be of the water-in-oil type or of the oil-in-water type and can have a thick consistency such as that of a "mayonnaise".

For a so-called "ultra-low volume" application, entailing spraying as very fine droplets, solutions in organic solvents, which contain from 70 to 95% of active compound, are prepared.

The compositions according to the invention can contain other ingredients, for example protective colloids, adhesives or thickeners, thixotropic agents, stabilisers or sequestering agents, as well as other substances which are known to have pesticidal properties, in particular insecticides or fungicides.

The present invention also includes within its scope a method of treating useful plants, for example to assist the setting of fruit, to prevent the shedding of leaves or fruit or to increase the formation of roots, which comprises applying to the plant and/or its environment a composition comprising an amidoxime derivative of general formula II and a carrier therefor and/or at least one surface-active agent as hereinbefore described.

A method for the control of weeds is also another aspect of the present invention, said method comprising applying to the weeds, or to a locus in which weeds are growing or are expected to grow, a composition as mentioned above for treating useful plants.

Claims

WHAT WE CLAIM IS:

1. Amidoxime derivatives of the general formula:

wherein R3 and R4 are the same or different and each represents a hydrogen atom, an alkyl radical containing from 1 to 4 carbon atoms, an optionally substituted phenyl radical or an amino radical which is optionally substituted.

2. Amidoxime derivatives according to claim 1 wherein one or both of the symbols R3 and R4 represents a phenyl radical carrying one or two substituents selected from halogen atoms and alkyl radicals containing from 1 to 4 carbona toms, or an amino radical carrying one or two substituents selected from alkyl radicals containing from 1 to 4 carbon atoms and the phenyl radical.

3. Amidoxime derivatives according to claim 1 of the general formula:

wherein B represents the cyano radical or a group of the general formula:

wherein R5 and R6 are the same or different and each represents a hydrogen atom, an alkyl radical containing from I to 4 carbon atoms, the phenyl radical, or an amino radical which is optionally substituted by one or two radicals selected from alkyl radicals containing from 1 to 4 carbon atoms and the phenyl radical.

4. O- Carbamoylmethyl)-thiophene-2- carboxamidoxime.

5. O- Hydrazinocarbonylmethyl)-thiophene-2-carboxamidoxime.

6. O- N,N-Dimethylcarbamoylmethyl)-thiophene-2-carboxamidoxime.

7. O- N-Methylcarbamoylmethyl)-thiophene-2-carboxamidoxime.

8. O-[(2-Phenylhydrazino) carbonylmethyl]- thiophene-2-carboxamidoxime.

9. O-(Anilinocarbonylmethyl) -thiophene-2-carboxamidoxime.

10. O- N,N-dimethylhydrazinocarbonylmethyl)-thiophene-2-carboxamidoxime.

11. O- Cyanomethyl)-thiophene -2-carboxamidoxime.

12. Process for the preparation of an amidoxime derivative of general formula II as claimed in claim 1, wherein A represents a group of general formula III depicted in claim 1 and R2, R3 and R4 are as defined in that claim, which comprises reacting ammonia or an amine of the general formula HNR3R4 (wherein R3 and R4 are as defined in claim 1) with a compound of the general formula:

wherein R2 is as defined in claim 1, and X represents either a group -CO-O-R, in which R7 represents an alkyl radical containing from 1 to 4 carbon atoms, or a group -COC1, optionally in the form of the hydrochloride.

13. Process according to claim 12 in which X in general formula VI represents a group -CO-O-R1 R7 being as defined in claim 12, and the reaction is carried out at a temperature between 15 and 100"C, optionally under pressure, and either in an organic or aqueousorganic solvent medium or in the absence of a solvent when the reactants are liquid under the reaction conditions employed.

14. Process according to claim 12 in which X in general formula VI represents a group -COC1 and the reaction is carried out by reacting the hydrochloride of such a compound with a compound of the general formula NHR3R4 (wherein R3 and R4 are as defined in claim 1) at a temperature between 15 and 50"C and either in an inert solvent medium or in the absence of solvent when the reactants are liquid under the reaction conditions employed.

15. Process for the preparation of an amidoxime derivative of general formula II as claimed in claim 1, wherein A represents the cyano radical and R2 is as defined in claim 1, which comprises reacting an amidoxime of the general formula:

with a halogenonitrile of the general formula:

(wherein R2 is as defined in claim 1 and Y represents a halogen atom) in the presence of an alkaline condensation agent in an aqueous-organic solvent medium at a temperature of from 15 to 800C.

16. Process for the preparation of amidoxime derivatives of general formula II as claimed in claim 1, wherein R2 and A are as defined in claim 1, substantially as hereinbefore described with especial reference to any one of Examples 1 to 6.

17. Amidoxime derivatives of general formula II depicted in claim 1, wherein R2 and A are as defined in claim 1, when prepared by a process claimed in any one of claims 12 to 16.

18. Phytohormonal and herbicidal compositions which comprise, as active ingredient, at least one amidoxime derivative as claimed in any one of claims 1 to 11 in association with at least one carrier and/or surface-active agent compatible with the amidoxime derivative and suitable for use in agricultural or horticultural compositions.

19. Compositions according to claim 18 which contain from 0.005 to 95% by weight of amidoxime derivative.

20. Compositions according to claim 18 or 19 in which the surface-active agent is a non-ionic compound.

21. Compositions according to claim 18, 19 or 20, in which a carrier for the amidoxime derivative is water.

22. Compositions according to claim 18 substantially as hereinbefore described with especial reference to Example 7 or 8.

23. A method for the phytohormonal treatment of useful plants which comprises applying to a useful plant and/or its environment a composition as claimed in any one of claims 18 to 22.

24. A method according to claim 23 in which the carrier for the amidoxime derivative is water and the composition contains from 0.1 to 100 grams of amidoxime derivative per hectolitre of water.

25. A method for the control of weeds which comprises applying to the weeds, or to a locus in which weeds are growing or are expected to grow, a composition as claimed in any one of claims 18 to 22.

26. A method according to claim 25 in which the composition is applied to a weedinfested locus at a rate of application of amidoxime derivative of 0.5 to 10 kg per hectare.