IE50614B1 - Plant growth-regulating compositions containing cyclopropylaniline derivatives - Google Patents

Abstract

Cyclopropylaniline derivatives of the general formula: (wherein R represents a hydrogen atom or C1-4 alkyl radical, X represents a halogen atom and n represents zero, 1 or 2, the halogen atoms being the same or different when n is 2, Y represents a halogen atom and m represents zero or an integer from 1 to 4, the halogen atoms being the same or different when m is 2, 3 or 4, and R1 represents a hydrogen atom or C1-6 alkyl radical have been found to possess useful plant growth- regulating properties. All such compounds are new with the exception of 4-(2,2- dichlorocyclopropyl)-aniline and 4- cyclopropylaniline.

Description

PLANT GROWTH-REGULATING COMPOSITIONS CONTAINING CYCLOPROPYLANILINE DERIVATIVES The present invention relates to compositions for regulating plant growth containingj as the active ingredient» certain cyclopropylaniline derivatives and to the treatment of plants using such compounds.

It also relates to new cyclopropylaniline derivatives which can be used as the active ingredient in the compositions according to the invention» and also to the preparation of these derivatives.

In the text of the present patent application» 10 the expressions for regulating growth and growth regulators are taken to have their usual meaning in the French language, which corresponds to "growth substances in the Anglo-Saxon literature, the word growth relating to the production of living material and not simply to the modification of the size of plants Growth regulators are therefore to be understood hereafter as meaning products which are capable of modifying the physiology of plants in various ways.

The compositions for regulating plant growth according to the present invention contain, as the active ingredient, at least one cyclopropylaniline derivative of the general formula: wherein R represents a hydrogen atom or an alkyl radical containing from 1 to 4 carbon atoms, X represents a halogen atom and n represents zero, 1 or 2, the halogen atomsbeing the same or different when n is 2, Y represents a halogen atom and m represents zero or an integer from 1 to 4, the halogen atoms being the same or different when m is 2, 3 or 4, and represents a hydrogen atom or an alkyl radical containing from 1 to 6 carbon atoms. It is to be understood that halogen atoms represented by symbols X and Y may be identical or different. Preferably the halogen atoms are chlorine or bromine.

Two cyclopropylaniline derivatives within the scope of general formula I have already been described.

Thus» German Patent Application 2343606 (and corresponding United States Patent 3948973) discloses 4-(2,2-dichlorocyclopropyl)aniline as a starting material for the preparation of medicaments, and the review Journal of the American Chemical Society, Vol. 90, No. 13. 19th June 1968, pages 3404-3415, discloses 4-cyclopropylaniline ar.d also its use for the preparation of - 3 l-bromo-4-cyclopropylbenzene.

However, these documents neither mention or even suggest the possibility that the compounds described therein are active in the regulation of plant growth.

In addition to the compositions hereinbefore described the invention relates, by way of new products, to the cyclopropylaniline derivatives of general formula I, with the exception of the two compounds hitherto described in the literature, i.e. 4-(2,2dichlorocyclopropyl)aniline and 4-cyclopropylaniline.

The cyclopropylaniline derivatives according to general formula I can form salts by reaction with a suitable acid, e.g. hydrochloric, sulphuric, nitric or phosphorous acid. These salts, and also plant growth regulating compositions in which they are present, are included within the scope of the present invention. Of such acid addition salts, the hydrochlorides are preferred.

The invention relates very particularly to the cyclopropylaniline derivatives corresponding to the general formula: NH - Rx II wherein X^ represents a hydrogen or halogen (preferably chlorine or bromine) atom, X2 represents a halogen (preferably chlorine or bromine) atom, Y and R^ are as hereinbefore defined (R^ preferably being a hydrogen atom or a methyl or ethyl group), and p represents zero, 1 or 2, the halogen atoms represented by Y being the same or different when p is 2, and acid addition salts (in particular the hydrochlorides) thereof.

Preferably the halogen atoms represented by X^ and X2 are the same.

Thus, the invention relates more particularly, on the one hand, to plant growth-regulating compositions in which at least one compound of general formula XI, or an acid addition salt thereof, is present as the active ingredient and, on the other hand, by way of new products to the compounds of general formula II and their acid additior salts, with the exception of the known compound 4-(2,2-dichlorocyclopropyl)aniline.

Amongst the 4-cyclopropylaniline derivatives of general formula II, those in which (Y) represents a halogen atom attached to the 3-position of the benzene nucleus are preferred, and in particular 4-(2,2-dichloro cyclopropyl)-3-chloroaniline.

Typical compounds of general formula I which 5 are included in the plant growth-regulating compositions of the present invention are 4-(2,2-dichlorocyclopropyl)· 3- chloroaniline, 4-(2,2-dichlorocyclopropyl)-3-hromoaniline, 4-(2,2-dichlorocyclopropyl)-3-chloro-Nmethylaniline, 4-(2,2-dichlorocyclopropyl)-3-chloro10 N-ethylaniline, 4-(2,2-dichlorocyclopropyl)aniline and 4- (2,2-dibromocyclopropyl)aniline.

The cyclopropylaniline derivatives of general formula X can be prepared by the hydrolysis of a cyclopropylacetanilide of the general formula: R III (wherein the various to a compound of the symbols are as hereinbefore defined) general formula.: (Y) -NHIV m - 6 (wherein the various symbols areas hereinbefore defined), and optionally alkylating by known methods the primary amino group to a group -NH-R^, wherein R^, represents an alkyl group containing from 1 to 6 carbon atoms.

By the term known methods as used in this specification is meant methods heretofore used or described in the chemical literature.

Hydrolysis of the cyclopropylacetanilidc of general formula III can be effected by treatment with an aqueous solution of an acid, e.g. sulphuric acid or polyphosphoric acid, at a temperature between about 100° and 150°C, and preferably of the order of 130°C.

Alkylation of a cyclopropylaniline derivative of general formula IV can be carried out in accordance with a method analogous to that described in Organic Syntheses, Collective Volume IV, page 240 (in the case of the preparation of N-methyl-p-chloroaniline and N-ethyl-p-chloroaniline from p-chloroaniline) by reacting an alkyl orthoformate of the formula: (Rlt-0)3CH V (wherein R^, is as hereinbefore defined) with the cyclopropylaniline of general formula IV to give the cyclopropylformanilidt of the formula: (wherein the various symbols are as hereinbefore defined), and then hydrolysing the cyclopropylformanilide thus obtained.

The reaction of the alkyl orthoformate with the cyclopropylaniline is advantageously carried out in the presence of an acid at a temperature between about 100° and 25O°C. The hydrolysis of the cyclopropylformanilide is carried out by heating the reaction mixture under reflux in the presence of an acid.

At the end of the reaction(s), the products formed can be isolated by known methods, for example by filtration, by distillation of a solvent (if used) or by recrystallisation of the products formed from the reaction medium,, and then, if necessary, they can be purified in accordance with customary methods.

Advantageously, the compounds of general formula I obtained by process hereinbefore described are converted into acid addition salts by known methods, viz. by treatment with & suitable acid such as, for example, hydrochloric, sulphuric, nitric or phosphorous acid. - 8 The hydrochlorides of the cyclopropylaniline derivatives of general formula I are particularly advantageous because they are generally more soluble in water than the aniline bases' from which they are derived. Thus, the hydrochlorides are particularly advantageous for the preparation of compositions for agricultural use which are to be diluted with water.

The cyclopropylacotanilide starting materials of general formula III can be obtained by a two step procedure from the cyclopropylacetophenones of the general formula: wherein the various symbols are as hereinbefore defined. Step 1 (oxime formation) Reaction of a hydroxylamine salt, in the presence of sodium hydroxide, with a cyclopropylacetophenone of general'formula VII to give a cyclopropylacetophenoxime (VCT) according to the reaction scheme: - CH3 + ZNa + 2H20 - OH - CH3 + NII2OH.HZ + NaOH as hereinbefore defined.

(VIII) wherein X, Y, R, m and n and Z represents a monovalent or divalent anion of a strong acid, such as a chloride or sulphate anion.

The reaction is advantageously carried out by running an aqueous solution of sodium hydroxide into an agueous-organic solution containing hydroxylamine hydrochloride and the cyclopropylacetophenone at a temperature between about 60° and 100°C.

Step 2 (rearrangement) Conversion of the cyclopropylacetophenoxime of general formula VIII resulting from step 1 to give a cyclopropylacetanilide of general formula III, by the Beckmann rearrangement, according to the reaction scheme wherein the various symbols are as hereinbefore defined. This conversion is carried out under the conditions which can generally be used for the Beckmann rearrangement such as those described, in particular, in "Organic Reactions, II, Chapter 1.

Advantageously, it is carried out by reaction with a concentrated strong acid, such as sulphuric acid or polyphosphoric acid, at a temperature between about 100° and 150°C and preferably between 120° and 130°C.

Dilution of the reaction mixture resulting from step 2 with water and heating at a temperature between about 100° and 150°C leads to hydrolysis of the cyclopropylacetanilide of general formula III and the formation of a cyclopropylaniline of general formula IV. 614 - 11 The cyclopropylacetophenones of general formula VII wherein m is zero can be prepared by reacting acetyl chloride with the appropriate cyclopropyl-benzene. Some of these cyclopropylacetophenones have been described in the literature, in particular 4-cyclopropylacetophenone and 4-(2,2-dichlorocyclopropyl)-acetophenone, which have been described in Bulletin of the Chemical Society of Japan, Vol. 46, No. 1, January 1973, pages 204-209.

The cyclopropylacetophenones of general formula VII wherein m is an integer from 1 to 4 can be prepared by reacting a halogen with the corresponding cyclopropylacetophenone unsubstituted by halogen on the phenyl nucleus. The halogenation can be carried out in an anhydrous medium in an inert organic solvent in the presence of a catalyst of the Lewis acid type, such as AlClg and FeCl^.

The preparation of cyclopropylaniline derivatives of general formula I [with the exception of 4-(2,2-dichlorocyclopropyl)aniline and 4-cyclopropyl aniline] and acid addition salts thereof, by the process hereinbefore described is a feature of the present invention. - 12 The following Examples illustrate the invention. The structure of the compounds described was confirmed by infra-red spectrometry and/or by nuclear magnetic resonance spectrometry (NMR), the NMR spectra having been run at 60 Megahertz, in DMSO, using hexamethylenedisiloxane as the internal standard.

EXAMPLE 1: Preparation of 4-(2,2-dichlorocyclopropyl)3-chloroaniline (Compound 1) Acetyl chloride (98.1 g) is run dropwise into a suspension of aluminium chloride (167 g; 1.25 mols) in anhydrous dichloroethane (350 ml) at a temperature between 0 and 5°C. 2,2-Dichlorocyclopropylbenzene (187 g; 1.0 mol) is then run in dropwise at the same temperature in .the course of 2 hours.

The mixture is stirred in the cold until the evolution of gas has ended. After returning to ambient temperature, the reaction mixture is poured onto ice (1 kg) and concentrated hydrochloric acid (50 ml).

After stirring for 30 minutes, the organic phase is decanted and the aqueous phase is extracted with methylene chloride (3 x 100 ml), and the combined organic phases are subsequently washed with water (200 ml) and then with a saturated aqueous solution of sodium bicarbonate (200 ml), dried over anhydrous sodium sulphate, evaporated and distilled under 0.002 mm Hg, 2,2-dichloro50614 - 13 cyclopropyl-acetophenone (197.8 g; yield 86%) thus being collected.

The 2,2-dichlorocyclopropylbenzene used as the starting material is prepared in accordance with the procedure described in Tetrahedron Letters, 1969, page 4569, and Chem. Ber., 108, 2803-2808 (1975).

A solution of 4-(2,2-dichlorocyclopropyl)acetophenone (96.0 g; 0.42 mol) in anhydrous dichloroethane (75 ml) is run dropwise into a dispersion of aluminium chloride (140 g: 1.05 mols) in dichloroethane (75 ml) at a temperature between 0 and 5°C. Chlorine gas (33.0 g; 0.46 mol) is then dissolved in the mixture in the course of 45 minutes, tho temperature always being kept between 0 and 5°C. The reaction mixture is then run onto ice (700 g) and concentrated hydrochloric acid (25 ml), and the organic phase is decanted and washed with a 10% aqueous solution of sodium bicarbonate (2 x 100 ml), dried over sodium sulphate and evaporated.

The crude product is recrystallised twice from hexane and this yields 4-(2,2-dichlorocyclopropyl)-3chloroacetophanone (53.0 g).melting at 74°C; yield: 48%.

A solution of sodium hydroxide (26.4 g: 0.66 mol) in water (50 ml) is run dropwise in the course of 15 minutes into an aqueous-alcoholic solution [ethanol (500 ml) + water (100 ml)] of hydroxylamine hydrochloride (46 g; 0.66 mol) and 4-(2,2--dichlorocyclo50614 - 14 propyl)-3-chloroacetophenone (158.1 g) heated to the boiling point.

When the introduction has ended, the reaction mixture is kept at the boil for 1 hour, the ethanol is then evaporated off in vacuo and the oxime precipitates.

It is filtered off, washed with water and dried.

The crude compound is recrystallised from a hexane/cyclohexane mixture and this yields 4-(2,2-dichlorocyclopropyl)3-chloroacetophenoxime (119.0 g) melting at 102°C (yield 71.2%). 4-(2,2-Dichlorocyclopropyl)-3-chloroacetophenoxime (58.2 g) is solubilised in concentrated sulphuric acid (55 ml) at a temperature between 10 and 15°C.

The resulting viscous solution is then run dropwise into concentrated sulphuric acid (18 ml), heated to 120-l25°C, at a rate such that the temperature remains between 120 and 130°C without supplying external heat.

Once the addition has ended, this temperature is maintained for 10 minutes by heating; the reaction mixture is ther collect to about 60°C, water (73 ml) is added and the mixture is heated at the boil for 2 hours.

On cooling, whilst stirring, the aniline eulphate precipitates. It is filtered off, washed with water and then treated with a 5N aqueous sodium hydroxide solution (70 ml) and methylene chloride (100 ml). - 15 The methylene chloride solution is washed with water and then dried over anhydrous sodium sulphate. After evaporating off the solvent, the resulting black oil (36.5 g) crystallises. It is recrystallised from a mixture of petroleum ether (90%) and cyclohexane (10%). This yields 4-(2,2-dichlorocyclopropyl)-3chloroaniline (28.0 g) melting at 66.5°C; yield 66.5%.

Elementary composition Calculated Found c% 45.67 45.97 H% 3.38 3.27 N% 5.92 5.31 Cl% 45.03 44.62 EXAMPLE 2: Preparation of 4-(2,2-dichlorocyclo15 propyl)aniline (Compound 2) The procedure of the preceding Example is followed, using the same starting materials, except that the 4-(2,2-dichlorocyclopropyl)acetophenone resulting from the acetylation, is not subjected to chlorination but is directly converted by oxime formation, rearrangement and hydrolysis, under the conditions indicated in the said Example.

This yields 4-(2,2-dichlorocyclopropyl)aniline melting at 62.1°C. · - 16 Elementary composition Calculated Found c% 53.49 53.86 H% 4.49 4.65 N% 6.93 6.74 Cl% 35.08 35.30 EXAMPLES 3 AND 4 The following compounds were prepared by following the procedure described in Examples 1 and 2, using the appropriate starting materials: 4-(2,2-dichlorocyclopropyl)-3-bromoaniline (Compound 3), obtained with a yield of 13%, in the form of a light brown liquid, and 4-(2,2-dibromocyclopropyl)aniline (compound 4), obtained with a yield of 6.4%, in the form of a rod-brown liquid.

EXAMPLE 5: Preparation of 4-(2,2-dichlorocyclopropyl)3-chloro-N-methylaniline (compound 5) The 4-(2,2-dichlorocycloprcpyl)-3-chloroaniline obtained in Example No. 1 is used as the starting material. 4-(2,2-Dichlorocyclopropyl)-3-chloroaniline (47.3 g: 0.2 mol), trimethyl orthoformate (31.8 g; 0.3 mol) and concentrated sulphuric acid (0.8 g) are placed in a 250 ml tiree-necked round-bottomed flask fitted with a Vigreux column, an ordinary condenser and - 17 a thermometer. The reaction mixture is heated to 115-120°C and the ethanol formed is distilled off.

The mixture is then heated at 165°C for 45 minutes.

After cooling, the crude product is purified hy liquid phase chromatography on silica. This yields N-methyl4-(2,2-dichlorocyclopropyl)-3-chloroformanilide (32.3 g) melting at 90°C.

The compound is placed in a 250 ml roundbottomed flask together with 10% hydrochloric acid (100 ml) and the mixture is heated under reflux for 2 hours.

After cooling to 10°C, the reaction mixture is neutralised with a 15% aqueous potassium hydroxide solution. The product is extracted with diethyl ether and the extract is washed with water and dried over anhydrous sodium sulphate. After evaporating off the diethyl ether, the crude product is subjected to liquid phase chromatography on silica.

This yields 4-(2,2-dichlorocyclopropyl)-3chloro-N-methylaniline (20.7 g) having a refractive index n^2 = 1.5878. Yield = 71.6%.

EXAMPLE 6 By following the procedure described rn Example 5, using the appropriate starting materials, 4-(2.2-dichlorocyclopropyl)-3-chloro-N-ethylaniline (Compound 6), having a refractive index nQ = 1.57810, is obtained. Yield: 63%. - 18 EXAMPLE 7; Preparation of 4-(2,2-dichlorocyclopropyl)3-chloroaniline hydrochloride (Compound 7) 4-(2,2-Dichlorocyclopropyl)-3-chloroaniline, the preparation of which is described in Example No. 1, is used as the starting material. 4-(2,2-Dichlorocyclopropyl)-3-chloroaniline (4 g; 0.017 mol), ethanol (10 ml) and 5% hydrochloric acid (120 ml) are introduced into a 250 ml roundbottomed flask suromounted by a reflux condenser. The mixture is heated under reflux for 30 minutes. After cooling, the hydrochloride precipitates. It is filtered off and dried at 50°C in vacuo (6 mm Hg).

This yields 4-(2,2-dichlorocylopropyl)-3chloroaniline hydrochloride (2.7 g) melting at 216°C, i.e. a yield of 58.7%. Elementary composition Calculated Found C% , 38.16 38.72 H% 3.53 3.57 N% 4.95 4.90 Cl% 25.09 25.86 EXAMPLE 8 TO 10 The following compounds were prepared following the procedure described in Example 7, respectively using Compounds 3, '? and 5 as the starting materials: - 19 Compound fl: 4-(2,2-dichlorocyclopropyl) 3-bromoaniline hydrochloride.

M.p.: 214-215°C Elementary composition Calculated Found C% 34.02 33.08 H% 2.83 2.80 N% 4.41 4.35 Cl% 33.54 32.17 Compound 9: 4-(2,2-dichlorocyclopropyl) aniline hydrochloride.

M.p.: above 250°C Elementary composition Calculated Found C°/o 45.28 45.92 H% 4.Ϊ9 3.80 N% 5.87' 5.01 Cl% 44.65 44.52 Compound 10; 4-(2,2-dichl'orocyclopropyl) •N-methylaniline hydrochloride. M.p.: 151°C Elementary composition Calculated Found C% 41.81 42.14 H% 3.83 3.85 N% 4.88 4.85 Cl% 49.47 49.25 0 614 - 20 In the experiments described below in Examples I to IV, the term solution" is to be understood as meaning either an aqueous solution in the case where the active ingredient is water-soluble or, in the opposite case, an aqueous dispersion or emulsion obtained by diluting with water, respectively, either a wettable powder comprising 20% by weight of active ingredient, or an emulsifiable concentrate containing about 200 g/litre of active ingredient. These experiments are carried Out either in a greenhouse or in the open field, the leaves of plants, such as bean and soya plants, being treated with a solution in which the content of active ingredient to be tested can vary from 0.1 g/litre to 20 g/litre. The biometric and morphological change, with time, of the treated plants is then observed and is compared with that of control plants treated under the same conditions with a solution which does not contain active ingredient.

EXAMPLE I: Greenhouse experiment or, beans (Phaseolus vulgaris) of the Contender variety A solution of the ingredient to be tested is prepared, at the desired concentration, by diluting, with water, an emulsifiable concentrate having the following composition: 14 - 2L Ingredient to he tested 206 g Wetting and emulsifying agent (mixture 4/1 by weight of an ethylene oxide/ castor oil condensate containing 30 to 33 ethylene oxide units, and of sodium dodecylbenzenesulphonate) 102 g solvent (aromatic hydrocarbons originating from petroleum fractions) 692 g Bean seeds are sown in 9 x 9 x 9 cm pots filled with light agricultural earth and are then covered with a half-centimetre thick layer of earth, and the pots are kept in a green house at ambient temperature, under 70% relative humidity, and are watered by sub-irrigation.

When the bean plants have reached the stage of two developed primordial leaves and a terminal bud which is ready to open, their foliage is treated by spraying with the previously prepared solution, at a rate of about 500 litres/hectare of solution, for active ingredient doses ranging from 2 to 8 kg/hectare.

The treated pots are subsequently placed in troughs which are intended to receive the moistening water by sub-irrigation, and are then kept for 35 days at ambient temperature under 70% relative humidity.

After these 35 days, it is observed that the plants treated with Compound 1 at a rate of 8 kg/hectare - 22 have an average size equal to half that of the controls, and that they also show a very significant development of the side shoots originating from the axillary buds, compared with the controls. For doses of 2 and 4 kg/hectare, the plants treated with Compound 1 have an average size respectively equal to 80% and 40% of that of the controls. For a dose of 8 kg/hectare the plants treated with Compounds 2, 5, 6» 7, 9 and 10 have an average size equal to 50% of that of the control, as well as the plants treated with Compounds 2, 6, 7, 8, and 10 at 4 kg/hectare.

For a dose of 2 kg/hectare the plants treated with Compounds 5, 6, 7 and 9 have an average size equal to 75% of that of the control, as well as the plants treated with Compound 5 at 4 kg/hectare.

EXAMPLE II; Greenhouse experiment on soya (Glycine max) of the Amsoy 71 variety A solution prepared by diluting, with water, the same emulsifiable concentrate as in Example I is used.

Soya eeeds, inoculated beforehand with rhizobium, are sown (1 seed per pot) in 20 x 20 x 20 cm pots containing equal proportions of peat, sand and humus, and the pots are kept in a greenhouse, as in Example ΐ, except that they are watered from the surface - 23 When the soya plants have reached the stage of 3 developed trifoliate leaves, i.e. about 30 days after the start of the experiment, the foliage is treated by spraying it, as in Example I, at a rate of 500 litres/hectare of solution. The treated pots are then kept in a greenhouse for 15 days at ambient temperature under 70% relative humidity.

After these 15 days, it is observed that the plants treated with Compound 1 at a dose of 2 kg/hectare of active ingredient show an average increase of 50% in the number of secondary ramifications, compared with the control.

EXAMPLE III: Open-field experiment on soya (Glycine max) of the Amsoy 71 variety On 15th May, soya seeds, inoculated beforehand with rhizobium, are sown in plots, each of 12 m .

When the soya plants are at the stage at which the third true leaf is fully open (i.e. about one month after the start of the experiment), these plants are treated by spraying them with a solution prepared by diluting with water, co the desired concentration, the same emulsifiable concentrate as in Example I, and by applying this solution at the rate of 3 litres per plot (2500 litres/hectare).

For each dose, two experiments are carried out in different plots. Three and a half months after the - 24 treatment, the number of fructiferous ramifications (i.e. ramifications carrying pods), on the one hand, and the number of pods formed on the main stems and on the fructiferous ramifications, on the other hand, are counted in the case of the treated plots and the control plots, and the average values relating to one soya plant are calculated.

Under these conditions, it is observed that, at a dose of 2 kg/hectare of active ingredient, Compound 1 gives the following one soya plant)r :s (values expressed for Compound 1 Control 3.7 1.6 .4 .2 14.0 8.7 Number of fructiferous ramifications Number of pods on the main stem Number of pods on the fructiferous ramifications EXAMPLE IV; Open-field experiment on soya (Glycine max) of the Amsoy 71 variety At the end of July, soya seeds are sown, in a 3 x 10 m plot, in two parallel rows which are each 10 m long and are spaced 0.50 m apart.

The solution used is prepared by diluting, with water, to the desired concentration, the same emulsifiable concentrate as in Example I. 614 - 25 On 30th August, when the soya plants are at the stage at which six trifoliate leaves are fully open, the plants in the first row are treated with the previously prepared solution so that the dose of active ingredient applied to the first row is 1 kg/hectare, the second row not receiving any treatment so that it can be used as a control. The results observed are indicated below: Dose of active ingredient Number of ramifications (100 plants) Number of pods (100 plants) Weight of grains harvested (100 plants) Weight of 1000 grains Control Compound 1 0' 162 3111 1436 g 162 g kg/hectare 195 3749 1603 g 156 g The results show that the treatment carried out using Compound 1, under -che conditions indicated above, leads to an increase both in the number of fructiferous ramifications and in the number of pods on the soya plants.

The results of these experiments clearly show the remarkable properties of the cyclopropylaniline derivatives of general formula I which compounds can therefore be used on all kinds of monocotyledonous - 26 (e.g. graminaceous) or dicotyledonous plants, such as those on large-scale farms and industrial farms, fruit plants, vegetable plants, ornamental plants» medicinal plants and plants grown for perfume, in order to increase the yields, promote the ramification, modify the habit, reduce the size in order to obtain more compact plants, and the like.

For their use in practice, the cyclopropylaniline derivatives of general formula X and salts thereof are rarely employed by themselves. Most frequently, they form part of compositions which generally comprise, in addition to the active ingredient according to the present invention, a carrier and/or a surface-active agent compatible with the compound and suitable for use in agricultural or horticultural compositions.

In generax terms, these compositions contain from 0.001 to 95% by weight of active ingredient in association with a carrier and/or up tc 20% by weight of a surface-active agent.

The term carrier·', in the sense of the present description, denotes an organic or inorganic natural or synthetic material with which the active ingredient is associated in order to facilitate its application to the plant, to seeds or to the soil, or in order to facilitate its transportation or handling. 0614 - 27 The carrier can be solid (e.g. clays, natural or synthetic silicates, calcium carbonate, magnesium carbonate or calcium sulphate) or liquid (e.g. water, alcohols, ketones, ethers, esters, aromatic hydrocarbons, halogenohydrocarbons or petroleum fractions).

The surface-active agent, for the purpose of the present description, can be a wetting, dispersing or emulsifying agent which can be ionic or non-ionic. Examples which may be mentioned are nonionics, such as condensates of ethylene oxide with fatty alcohols, fatty acids, fatty amides, fatty amines or alkylphenols, fatty acid esters of sorbitol, and sucrose derivatives, anionics, such as the salts of lignosulphonic acids, alkylarylsulphonic acids, alkyl-sulphosuccinates and alkyl-sulphosuccinamates,. and amino-acid derivatives, cationics, such as acetates of alkylamines or of imidazoline, and amphoterics, such as alkylbetaines or sulphobetaines.

In addition uo the active ingredient, the carrier and/or the surface-active agent, the compositions according to the invention can contain other additives, such as dispersing agents which are not surface-active, peptising agents, protective colloids, thickeners, adhesives which increase the resistance to rain, stabilisers, preservatives, corrosion inhibitors, dyestuffs, sequestering agents, anti-foam agents, anti50614 - 28 caking agents and anti-freeze agents.

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

The wettable powders are usually prepared by premixing the active ingredient with a solid carrier and wetting and dispersing agents, in the form of powders, so that they contain from 10 to 95% by weight of the active ingredient and from 0.5 to 20% by weight of surfaceactive agentis). This premixture is then ground either in a mill, e.g. a pin-disc mill equipped with a powder selector, or in an air jet mill, the latter apparatus being preferred for the active ingredients with a low melting point.

By way of example, the compositions of several wettable powders according to the invention are given hereafter, the percentages being expressed by weight; EXAMPLE 11 Active ingredient (Compound lj 25.0% sodium alkyl-sulphosuccinate (wetting agent) 2.0% alkali metal salt of a condensed naphthaler-.esulphonic acid (dispersing agent) 7.0% kaolin clay 66.0% - 29 EXAMPLE 12 Active ingredient (Compound 2) 50.0% sodium alkylnaphthalenesulphonate (wetting agent) 3.0% alkali metal lignosulphonate (dispersing agent) 10.0% kaolin clay 37.0 % EXAMPLE 13 Active ingredient (compound 1) 50.0% ethylene oxide/fatty alcohol condensate (wetting agent) 1.4% alkaline earth metal lignosulphonate (dispersing agent) 10.0% fossil silica 38.6% EXAMPLE 14 Active ingredient (compound 1) 50.0% sodium alkylnaphthalenesulphonate (wetting agent) 4.0% alkali metal salt of condensed sulphonic acids (dispersing agent) 3.0% kaolin clay 20.0% fossil silica 23.0% - 30 EXAMPLE 15 Active ingredient (Compound 1) 60.0% ethylene oxide/alkylphenol condensate (wetting agent) 2.0% alkali metal salt of a condensed naphthalenesulphonic acid (dispersing agent) 5.0% kaolin clay 33.0% The water-soluble powders are usually obtained by mixing 20 to 95% by weight of active ingredient, 0 to 10% of an anti-caking filler and 0 to 1% of a wetting agent, the remainder consisting of a water-soluble filler, which is mainly a salt.

An example of the composition of a watersoluble powder is given below, the stated percentages being by weight.

EXAMPLE 16 Active ingredient {Compound 1) 80.0% anionic wetting agent (alkali metal alkylnaphthalenesvlphonate) 0.5% anti-caking silica 4.0% sodium sulphate (soluble filler) 15.5% The dusting powders can be prepared in the same way as the wettable powders, but without the surface-active agents, dispersing agents and protective colloids, which are not necessary in these formulations. In this case, the solid carrier is specially chosen to facilitate grinding, to absorb, if the active - 31 ingredient is liquid, and to guarantor· flowability.

The granules and microgranules, which generally contain a low proportion of active ingredient, can be manufactured beforehand and then impregnated, or manufactured in bulk, e.g. by atomisation or by extrusion. Xn the latter case, they require the addition of binders and hygroscopic products in order to ensure their rapid disaggregation on the soil. They generally contain from 0.5 to 25% by weight of active ingredient and from 0 to 10% by weight of additives, such as stabilisers, slow-release modifiers, binders and solvents.

The emulsifiable concentrates contain the active ingredient dissolved in a solvent (generally an aromatic hydrocarbon) and, when necessary, an auxiliary solvent or co-solvent which can be, for example, a ketone, an ester or an ether. They contain from 10 tc 60% by weighr/volume of active ingredient(s) and from 2 to 20% by weight/volume of emulsifying agent and can be prepared, for example by dissolution of the active ingredient, in the solvent or in the mixture of solvents and emulsifier, in a vat equipped with a good means of agitation and with a means of circulating fluid for heating or cooling.

By way of example, the composition of two emulsifiable concentrates according to the invention - 32 are given below.

EXAMPLE 17 Active ingredient (Compound 1) 200 g calcium alkylarylsulphonate 20 g ethylene oxide/nonylphenol condensate containing 9 molecules of ethylene oxide 80 g solvent (aromatic hydrocarbons originating from petroleum fractions) q.s.p. 1 litre (i.e. 667g) EXAMPLE 18 Active ingredient (Compound 1) 400 g sodium dodecylbenzenesulphonate 24 g ethylene oxide/nonylphenol condensate containing 10 molecules of ethylene oxide IG g cyclohexanone 200 g solvent (aromatic hydrocarbons) q.s.p. 1 litre The so-called flowable suspension concentrates which can also be applied by spraying, after dilution with water, are prepared so as to give a stable fluid preduct which does not form e. deposit.

They usually contain from 10 to 50% by weight of active ingredient, from 0.5 to 15% by weight of surfaceactive agents, fro.'i. Ό.5 to 10% by weight of protective colloids or anti-sedimentation agents, from 0 to 10% of various additives, such as anti-foam agents, thickeners, stabilisers, adhesives and antifreeze agents, and, as the carrier, water or an organic 614 - 33 liquid in which the active ingredient is insoluble, or a mixture of both. Certain organic solids or inorganic salts can be dissolved in the carrier in order to delaysedimentation or as an anti-freeze agent for the water.

These suspension concentrates can be prepared, for example, by dispersing the pre-ground active ingredient in a liquid carrier, which can be water, a vegetable or mineral oil or an emulsified mixture of the two, containing the auxiliary ingredients, such as the viscosity regulator, the preservative and the antifreeze agent, and then grinding the dispersion in a ball mill.

Aqueous dispersions and aqueous emulsions, e.g. compositions obtained by diluting with water a wettable powder or an emulsifiable concentrate according to the invention, are included in the general scope of the present invention. These emulsions can he of the water-in-oil type or of the oil-in-water type and they can have a thick consistency, such as that of a mayonnaise.

Ali these compositions can he applied to the plants by various methods, such as spraying onto the aerial part of the plants, soaking the seeds, the plants, soil balls around the roots, the roots or the fruits. watering the soil or injection into the plant.

S0Q14 - 34 Finally, the present invention relates to a method for modifying the growth of plants (i.e. for modifying the physiology of plants in various ways) which comprises applying to the plant or its environment an effective amount of at least one compound of general formula I, or a salt thereof, preferably in association with a carrier and/or at least one surfaceactive agent as hereinbefore described. The dose of active ingredient applied can vary according to different factors such as, for example, the type of plant or crop to be treated, its stage of development, the climatic conditions and the nature of the land.

In practice, the treatments according to the invention are carried out by applying to, for example, a crop15 growing area doses of cyclopropylaniline compound ranging from 0.050 kg/hectare to 10 kg/hectare.

Claims (35)

1. A plant growth-regulating composition which comprises, as active ingredient, at least one cyclopropylaniline derivative of the general formula: G (wherein R represents a hydrogen atom or an alkyl radical containing from 1 to 4 carbon atoms, X represents a halogen atom and n represents zero, 1 or 2, the halogen atoms being the same or different when n is 2, Y represents a halogen atom and m represents zero or io an integer from 1 to 4, the halogen atoms being the same cr different when m is 2, 3 or 4, and R^ represents a hydrogen atom or an alkyl radical containing from 1 to 6 carbon atoms) or an acid addition salt thereof, in association with a carrier and/or a surface-active \S agent compatible with the compound and suitable for use in agricultural or horticultural compositions.

2. A plant growth-regulating composition according tc claim 1 which comprises, as active ingredient, at least one cyclopropylaniline derivative of the general Σΐΰ formula: - 36 Η wherein Χ^ represents a hydrogen or halogen atom, X 2 represents a halogen atom, Y and are as defined in claim 1, and p represents zero, 1 or 2, the halogen atoms represented by Y being the same or different E, when p is 2i and acid addition salts thereof.

3. A plant growth-regulating composition according to claim 2 wherein (Y)p represents a halogen atom attached to the 3-position of the benzene nucleus.

4. A plant growth-regulating composition according to claim 1, 2 or 3 wherein halogen atoms represented by symbols X and Y are the same or different and are chlorine or bromine atoms.

5. A plant growth-regulating composition according to any one of claims 1 to 4 wherein represents a hydrogen atom. - 37 (ι. Λ [il.mL growth—rogululϊng compos j Li on according to any one of claims 1 to 4 wherein represents a methyl or ethyl group.

6. 7. A plant growth-regulating composition 5 according to claim 1 in which the active ingredient is 4-(2,2-dichlorocyclopropyl)-3-chloroaniline or an acid addition salt thereof.

7. 8. A plant growth-regulating composition according to claim 1 in which the active ingredient \’o is one or more of 4-(2,2-dichlorocyclopropyl)-3bromoaniline, 4-(2,2-dichlorocyclopr opyl)-3-chloro-Nmethylaniline, 4-(2,2-dichlorocyclopropyl)-3-chloroN-ethylaniline, 4-(2,2-dichlorocyclopropyl) aniline and 4-(2,2-dibromocyclopropyl)aniline, or an acid addition IS salt of any such compound.

8. 9. A plant growth-regulating composition according to any one of claims 1 to 8 in which the acid addition salt of the cyclopropylaniline derivative is the hydrochloride.

9. 10. A plant growth-regulating composition according to any one of claims 1 to 9 in the form of a wettable powder, a soluble powder, a dusting powder, granules, a solution, emulsifiable concentrate or emulsion, a suspension concentrate, suspension or dispersion. - 38

10. 11. A composition according to any one of claims 1 to 10 in which the carrier is water and, in addition, the composition contains a surface-active agent.

11. 12. A composition according to any one of claims 1 to 10 in which the carrier is an organic solvent for the cyclopropylaniline derivative and, in addition, the composition contains a surface-active agent. Vd

12. 13. A composition according to any one of claims 1 to 10 which comprises a said cyclopropylaniline derivative, an organic solvent therefor, water and a surface-active agent.

13. 14. A plant growth-regulating composition according to any one of the preceding claims in which the quantity of cyclopropylaniline derivativci or acid addition salt thereof, is from 0.001% to 95% by weight of the composition.

14. 15. A plant growth-regulating composition 'JVi according to claim 1 substantially as hereinbefore described with especial reference to any one of Examples 11 to 18.

15. 16. Cyclopropylaniline derivatives of the general formula: (Y)„ (Χ) η- _NH ’ R 1 [wherein R represents a hydrogen atom or an alkyl radical containing from 1 to 4 carbon atoms, X represents a halogen atom and n represents zero, 1 or 2, the halogen atone being the same or different when 5 n is 2, Y represents a halogen atom and m represents zero or an integer from 1 to 4, the halogen atoms being the same or different when m is 2, 3 or 4, and R^ represents a hydrogen atom or an alkyl radical containing from 1 to 6 carbon, atoms with the exclusion of ° 4-(2,2-dichloropropyl)aniline and 4-cyclopropylaniline] and acid additxon salts thereof.

16. 17. Cyclopropylaniline derivatives according to claim 16 of the general formula: H X. lo \S 2,0 - 40 [wherein X^ represents a hydrogen or halogen atom, X? represents a halogen atom, Y and are as defined in claim 1, and p represents zero, 1 or 2, the halogen atoms represented by Y being the same or different when p is 2, with the exclusion of 4-(2,2-dichlorocyclopropyl)aniline] and acid addition salts thereof.

17. 18. Cyclopropylaniline derivatives according to claim 17 wherein (Y) represents a halogen atom attached to the 3-position of the benzene nucleus.

18. 19. Cyclopropylaniline derivatives according to claim 16, 17 or 18 wherein halogen atoms represented by symbols X and Y are the same or different and are chlorine or bromine atoms.

19. 20. Cyclopropylaniline derivatives according to any one of claims 16 to 19 wherein represents a hydrogen atom. •

20. 21. Cyclopropylaniline derivatives according to any one of claims 16 to 19 wherein represents a methyl or ethyl group.

21. 22. 4-(2,2-Dichlorocyclopropyl )-3--chloroaniline.

22. 23. 4-(2,2-Dichlorocyclopropyl)-3-bromoaniline.

23. 24. 4-(2,2-Dichlorocyclopropyl)-3-chloro-Nmethylaniline - 41

24. 25. 4-(2,2-Dichlorocyclopropyl)-3-chloro-Nethylaniline.

25. 26. 4-(2,2-Dibromocyclopropyl)aniline.

26. 27. Acid addition salts of a cyclopropylaniline derivative as claimed in any one of claims 18 to 26.

27. 28. The hydrochloride of a cyclopropylaniline derivative as claimed in any one of claims 16 to 26.

28. 29. A process for the preparation of a cyclcpropylaniline derivative as claimed in claim 16 which comprises the hydrolysis of a cyclopropylacetanilide of the general formula: (X) R NH (Y) symbols general C - CH, II III (wherein the various to a compound of the m are as defined in claim formula: 1) NH, IV (wherein the various symbols are as defined in claim 1), and optionally alkylating by known methods the primary amino group to a group -NH-R^, wherein R^, represents an alkyl group containing from 1 to 6 carbon atoms. - 42

29. 30. A process according to claim 29 in which the hydrolysis of the cyclopropylacetanilidc is effected by treatment with an aqueous solution of an acid at a temperature between about 100° and 150°C. S

30.

31. A process according to claim 29 or 30 followed by the step of converting by known methods the cyclopropylaniline derivative thus obtained into an acid addition salt.

32. A process according to claim 29, 30 or 31 lo substantially as hereinbefore described with reference to any one of Examples 1 and 3 to 10.

33. Cyclopropylaniline derivatives as claimed in claim 16, or acid addition salts thereof, when prepared by the process claimed in claim 29, 30, 31, or 32.

34. A method for modifying the growth of plants which comprises applying to the plant or its environment an effective amount of at least one cyclopropylaniline derivative of the general formula depicted in claim 1, or an acid addition salt thereof, preferably in association with a carrier and/or at least one surface-active agent. - 43

35. A method according to claim 34 in which the amount of cyclopropylaniline derivative applied to a locus is from 0.050 kg/hectarc to 10 kg/hectare.