IE48057B1 - Herbicidally active chloracetanilides, a process for their manufacture and their use - Google Patents

Abstract

Novel chloracetanilides of the formula I (wherein R1, R2 and R3 each represents H, C1-4-alkyl, halogen or F3C, R4 represents C1-6-alkyl and n is 1, 2 or 3) and their manufacture from chloroacetyl chloride and the appropriate sec-amine. The novel compounds of the formula I have both a herbicidal and a growth-regulating action, and accordingly may be made up with suitable carriers into herbicidal preparations and may be used for treating living plants and areas of land.

Description

The present invention is concerned with new herbicidally active chloracetanilides, with a process for the manufacture of these compounds and also with their use.

Halogeno-acetanilide derivatives having a herbicidai action are already known (see British Patent Specifications Nos. 1,455,474, 1,455,471, 1,422,473 and 1,008,851 and United States Patent Specification No. 3,547,620). However, they have only a narrow range of action and their action is strongly dependent on the soil.

The problem upon which the present invention is based has therefore been to develop a herbicide, which has a wide range of action and is not dependent on the soil.

This problem is solved in accordance with the present invention by the compounds of the general formula 1, as defined below.

The present invention. accordingly provides compounds of the general formula 1 in which Rp R2 and R3 each represents a hydrogen atom, an alkyl group containing 1 to 4 carbon atoms, a halogen atom or a trifluoromethyl group, R4 represents an alkyl group containing 1 to 6 carbon atoms and n represents 1, 2 or 3.

The meanings of the symbols R^, R2 and R3 may be the same or different.

The compounds of the present invention are distinguished by a broad soil-herbicidal action. They can be used for combating mono- and di-cotyledonous weeds.

Weeds that can be combated by means of these compounds by the pre-emergence method are, for example, Allium, Solanum, Senecio, Matricaria, Galium, Polygonum, Trifolium, Escholtzia, Digitalis, Phaoelia, Sorghum, Echinochloa, Setaria, Dlgitaris, Cyperus, Poa, Agrostis, Bromus, Lolium, Phleum, Dactylis and Festuca. - 4 For combating weeds there are generally used application quantities within the range of from 0.5 kg of active substance per hectare to 5 kg of active substance per hectare. The active compounds of the present invention have thereby also proved to be surprisingly selectively active in crops of useful plants, for example cotton, ground-nut, rape, stemkale, cauliflower, soya bean, pea, sugar beet, spinach and lettuce crops. When two or more compounds of the general formula 1 are used, the range of 0.5 to 5 kg per hectare refers of course to the total amount applied of these compounds.

The active compounds of the present invention have a further advantage in that they also exhibit growth-regulating properties .

As the further technically valuable changes in the development of plants caused by the compounds of the present invention there may be mentioned, for example, retardation of vertical growth, retardation of root development, stimulation of the growth of bud shoots or side-shoots from low-lying buds, intensification of the formation of plant colouring matters and improvement in the storage capacity of plant components.

The present invention accordingly also provides a herbicidal preparation which comprises a compound of the general formula 1, in admixture or conjunction with a suitable carrier. The preparation may of course contain one or more compounds of the general formula 1. 4805? - 5 The present invention further provides a method of protecting a living plant against weeds, wherein the area in the vicinity of the living plant is treated with a compound of the general formula 1.

The present invention further provides a method of protecting a crop area against weeds, wherein the crop area is treated with a compound of the general formula 1.

The present invention further provides a method of regulating the growth of a living plant, wherein the living plant is treated with a compound of the general formula 1.

The present invention further provides a pack which comprises a compound of the general formula 1 together with instructions for its use as a herbicide and/or for regulating the growth of a living plant.

The compounds of the present invention may be used either alone, or in admixture with one another or with other active substances. If desired, other plant protecting or pest-combating agents may be added depending on the purpose desired.

If it is intended to broaden the range of action other herbicides may also be added. As suitable herbicidally active cocomponents there may be mentioned, for example, active substances belonging to the groups of triazines, aminotriazoles, anilides, diazines, uracils, aliphatic carboxylic acids and halogeno48057 - 6 carboxylic acids, substituted benzoic acids and aryloxy” carboxylic acids, hydrazides, amides, nitriles, esters of such carboxylic acids, carbamic acid esters and thiocarbamic acid esters, ureas, 1,3,6-trichlorobenzyloxy-propanil and thiocyanate-containing agents. Among other additives there are to be understood, for example, non-phytotoxio additives, which give a synergistic increase in action with herbicides, for example wetting agents, emulsifiers, solvents and oily additives.

The active compounds of the general formula 1 or mixtures thereof are advantageously used in the form of herbicidal preparations, for example powders, strewable preparations, granules, solutions, emulsions or suspensions, with the addition of liquid and/or solid vehicles or diluents and, if desired, of surface-active agents, for example wetting, adherent, emulsifying and/or dispersing agents.

Suitable liquid carriers are, for example, water, aliphatic hydrocarbons, aromatic hydrocarbons, for example benzene, toluene and xylene, cyclohexanone, isophorone, dimethyl sulphoxide and dimethylformamide, and also mineral oil fractions As solid carriers there are suitable, for example, mineral earths for example tonsil, silica gel, talcum, kaolin, attaclay, limestone and silicic acid, and vegetable products, for example meals. - 7 As surface-active agents there may be mentioned, for example, calcium lignin sulphonate, polyoxyethylene alkyIphenol ethers, naphthalene sulphonic acids and salts therof, phenol sulphonic acids and salts thereof, formaldehyde condensates, fatty alcohol sulphates and also substituted benzene sulphonic acids and salts thereof.

The total amount of the active substance or substances in the various herbicidal preparations may vary within wide limits. For example, the preparations may contain approximately 5 to 95% by weight of active substance(s), approximately 95 to 5% by weight of liquid or solid carrier and, if desired, also up to 20% by weight of surface-active agent(s).

The active substances may be applied in the usual manner, for example with water as carrier in quantities of spray liquor of approximately 100 to 1000 litres per hectare. It is also possible to apply the active substances by the so-called low-volume method and ultra-low-volume method and it is also possible to apply them in the form of so-called microgranules.

As substituents represented by R^, Rj, and R^ in the general formula 1 there may be mentioned methyl, ethyl, n-propyl, isopropyl, n-butyl, sec.-butyl, isobutyl, tert, -butyl, fluoro, chloro, bromo, iodo and trifluoromethyl substituents.

The symbol R^ may represent, for example, a methyl, ethyl, propyl, isopropyl, n-butyl, sec.-butyl, isobutyl, ter.-butyl, n-pentyl or n-hexyl group. - 8 Among the compounds of the present invention that are distinguished by an outstanding action are especially those of the general formula 1 in which and R2 have identical or different meanings and each represents an alkyl group containing 1 to 4 carbon atoms, R^ represents a hydrogen atom, R^ represents an alkyl group containing 1 to 4 carbon atoms and n represents the number 1 or 2, The hitherto unknown compounds of the general formula 1 may be prepared, for example, by the process of the present invention, as defined below.

The present invention accordingly further provides a process for the manufacture of a compound of the general formula 1, wherein an aniline of the general formula 11 NH„ (11) in which R^, R2 and have the meanings given above, is reacted, preferably in the molar weight ratio within the range of from 2:1 to 3:1, with a compound of the general formula 111 X—CH2CH— (OCH2CH2) n—0R4 (ill) - 9 in which R4 and n have the meanings given above and X represents a hydroxyl group, a halogen atom or a 4—CH3—CgH4—SC>2—0— group, the reaction when X represents a hydroxyl group being carried out under pressure and, if desired, with the addition of water and a catalyst, preferably a nickel catalyst, and when X represents a halogen atom or a 4—CH3—CgH4—S02—0— group being carried out at a temperature within the range of from 20 to 200°C, if desired, with the addition of water and a catalyst, preferably a nickel catalyst, and when X represents a halogen atom or a 4—CH3—CgH4—S02—0— group being carried out at a temperature within the range of from 20 to 200°C, if desired with the use of an inert solvent, for example an organic solvent, for example toluene or xylene, and the resulting reaction product of the general formula IV R1 in which Rp R2, R3, R4 and n have the meanings given aboye, is reacted with chloracetyl chloride in the presence of an acid acceptor, for example an organic base, for example pyridine or triethylamine, or an inorganic base, for example sodium hydroxide, potassium hydroxide, sodium - 10 carbonate, potassium carbonate or magnesium oxide, and, if desired, of an organic solvent at a temperature within the range of from —10 to 105°C. The final reaction product may be isolated in a manner known per se. in the reaction between the product of the general formula IV and the chloracetyl chloride these reactants may be used in equimolar quantities but preferably, however, the chloracetyl chloride is used in excess.

The compounds of the present invention are generally almost colourless, odourless, sparingly mobile liquids, which readily dissolve in polar organic solvents, for example acetone, dimethylformamide and dimethyl sulphoxide, and are practically insoluble in water and gasoline.

The following Examples illustrate the invention. Example 1 illustrates the manufacture of the compounds of the present invention and Examples 2 and 3 illustrate the possible uses and superior action of the compounds of the present invention.

Example 1 Chloracetic acid /N-(3,6-dioxaheptyl)-2, 6-dimethylanilide/ A solution of 60.50 gm (0.5 mole) of 2,6-dimethylaniline and 68.50 gm (0.25 mole) of (paratolyl)-(1,4,7-trioxaoctyl)sulphone in 100 ml of toluene was heated for 20 hours under - 11 reflux. After cooling, water and 25 -ml a concentrated solution of sodium hydroxide were added and, after dilution with ethyl acetate, the organic phase was separated. It was then washed until almost neutral with water, dried over magnesium sulphate and after filtration concentrated in vacuo.

The residue was distilled in vacuo, and N-(3,6-dioxaheptyl) -2,6-dimethylaniline having a boiling interval of 119—131°C (0.4 Torr) was obtained.

Yield: 32.44 gms = 58.1% of the theoretical yield.

Into a solution of 11.15 gms (0.05 mole) of N-(3,6-dloxaheptyl) -2,6-dimethylaniline in 50 ml of ethyl acetate were introduced 13.82 gms (0.1 mole) in anhydrous potassium carbonate. There were introduced into the stirred suspension dropwise at 25—30°C while cooling with ice 11.29 gms (0.1 mole) of chloracetyl chloride, and the whole was further stirred for one hour. The mixture was left to stand for a few hours at room temperature. Water was then added and the mixture was extracted by agitation several times with ethyl acetate. The combined ethyl acetate phases were dried over magnesium sulphate and, after filtration, concentrated in vacuo.

After drying at room temperature under a high vacuum an almost colourless oil was obtained. - 12 Yield: 12.23 gins (= 81,6% of the theoretical yield) of chloracetic acid /N-(3,6-dioxaheptyl)-2, 6-dimethylanilide7. np° = 1.5250.

The following compounds of the present invention can be 5 prepared in an analogous manner.

Name of the Compound Physical Constant Chloracetic acid /N-(3,6-dioxaheptyl) anilide7 /° = 1.5260 Chloracetic acid /2,6-diethyl-N-(3,610 dioxaheptyl)-anilide7 np° = 1.5214 Chloracetic acid /N-(3,6-dioxaheptyl)-2methylanilide/ n„ = 1.5212 Chloracetic acid /f-(3,6-dioxaoctyl)-2, 6-dimethy1-anilide/ n^° = 1.5200 n„ = 1.5176 Chloracetic acid /2-chloro-N-(3,6dioxaoctyi)-6-methylanilide7 /° = 1.5252 Chloracetic acid /2,6-diethyl-N-(3,6dioxaoctyi)-anilide7 - 13 Name of the Compound Physical Constant Chloracetic acid /7-chloro-N-(3,6dioxaheptyl)-6-methylanilide7 np° = 1.5315 Chloracetic acid /N-(3,6-dioxaoctyl)-2methylanilide7 nJ?0 = 1.5092 Chloracetic acid /Ι,δ-ΰΙιηβίίιγΙ'-Ν’-^,δ, 9-trioxadecyl)-anilide7 1.5208 Chloracetic acid /2,6-diethyl-N-(3,6, 9-trioxadecyl)-anilide7 ηθ = 1.5190 Chloracetic acid /2-methyl-N-(3,6,9trioxadecyl)-anilide7 n^° = 1.5200 Chloracetic acid /2,6-dimethyl-N-(3,6,9, 12-tetraoxatetradecyl)-anilide7 n^° = 1.5104 Chloracetic acid /2»6-dlmethyl-N-(3,6, 15 9-trioxaundecyl)-anilide7 1.5140 n^ = 1.5225 Chloracetic acid /7-ethyl-6-methyl-N(3,6-dioxaheptyl)-anilide7 480S7 Example 2 In a series of tests carried out in a greenhouse the compounds of the present invention listed in the Table below were each sprayed at a rate of application of 3 kg of active substance per hectare, emulsified in 500 litres of water per hectare, on Digitaria s. and Eohinochloa e.g. as test plants by the pre-emergence method. Three weeks after the treatment the results thereof were evaluated and the results expressed by a numerical scale extending from 0 to 4, the value 0 representing no action and the value 4 representing destruction of the plant. As can be seen from the Table destruction of the test plants was achieved.

Digitaria Echinochloa Compound of the invention sanguinalis curs galli Chloracetic acid /N-(3,6-dioxaheptyl)2, 6-dimethylanilide7 Chloracetic acid /2,6-diethyl-N(3,6-dioxaheptyl)-anilide7 Chloracetic acid /N-(3,6-dioxactyl)2,6-dimethylanilide/ '’Chloracetic acid /N- (3,6-dioxaheptyl) 20 2-methylanilide7 - 15 Digitaria Compound of the Invention sanguinalis Chloracetic acid /2,6-diethyl-N-(3,6dioxaoctyl)-anilide/ 4 Chloracetic acid /2-chloro-N-(3,6dioxaoctyl)-6~raethylanilide7 4 Chloracetic acid /2-chloro-N-(3,6dioxaheptyl)-6-methylanilide7 4 Chloracetic acid /N-(3,6-dioxaoctyl)10 2-methylanilide7 4 Chloracetic acid //,6-dimethy1-N3,6,9-trioxadecyl)-anilide7 4 Chloracetic acid /7.,6-diethyl-N-(3,6,9trioxadecyl)-anilide7 4 Chloracetic acid /2-methyl-N-(3,6,9trioxadecyl)-anilide/ 4 Chloracetic acid /2,6-dimethy1-N(3,6,9,12-tetraoxatetradecyl)-anilide/ 4 Chloracetic acid /Σ,6-dimethy1-N20 (3,6,9-trioxaundecyl)-anilide7 4 Echinochloa curs galli - 16 Digitaria Echinochloa Compound of the invention sanguinalis curs galli Chloracetic acid ^/J-ethyl-e-methylN-(3,6-dioxaheptyl)-anilide? Untreated Example 3 In a series of tests carried out in a greenhouse two different types of soil were treated after sowing the plants listed in the heading of the Table below and before emergence thereof with the agents being tested at a rate of application of 1 kg of active substance per hectare. For this purpose the agents were in each case uniformly sprayed over the plants in the form of an aqueous emulsion using 500 litres of water per hectare. In this manner it was shown three weeks after the treatment that the action of the compound of the present invention, coupled with a minimal dependence on the soil, surprisingly exhibited a high selectivity and was an excellent herbicidal action against the weeds. The agent used for comparison exhibited a comparatively much weaker action which, furthermore, was strongly dependent upon the type of soil. The results are expressed by a numerical scale extending from 0 to 10, the value 0 representing destruction of the plant and the value 10 representing no damage. - 17 umqfizog snzadAo ΒχζΒΑχβχα Boxqoouxtpg unvnes umpirea ofoauas umuexog «ιηχχχν umapxoH ΜηογτΓχι uaz sonqqaq ssaa qoBtrfds qaaq zufing zaMOXJTXtieo aXBquiaqg adea qnu-punozD uoqqoa bAos fi o n •u c fi a> q +> m o o % υ ο ο Ο o o rt o rt ο ο o o s o rt ο ο o o o rt o rt ο ο o o o o ο rt ι—1 ΟΙ ο ο \Ο o CN O O H rt rt <0 ο ο <* ιη n O o rt o rt ο ο η O *t* o o rt rt rt ο ο 0 to in o o Ζ rt rt ο ο β 0 CN O o rt o rt •Η <Ν 1—1 Ρ CO o O ιΰ rt rt CN ι—1 ο rt CO o o Ή rt rt •Η ΓΠ (Ν 0 o CO o o Φ rt rt rt ο ο β. CO n o o «Ο rt rt Γ>, rt rt rt +1 φ rt ο Ο β τ? o co o O rt τ—1 Η Φ Ή rt rt rt d Ρ rd flj Ο Ο d rt O •«Φ 0 o rt rt rt ¢4 § rt rt rt >M Λ ο Ο 10 ni 1 o kO O o P rt Η Φ rt rt rt Φ Ρ r-i g ο Ο Φ >n o to O O rt γΗ Η •μ Xi rt rt rt fO W P I ο Ο Φ O 00 O o kO rt rt Τ3 rt rt rt CN Ο Ο Φ Ρ N O r> o o ( rt r—ί rt 0 rt rt rt »—> rt ο ο £ Λ P o O o o >1 ι—{ rt d> rt rt rt rt 4J & ο Ο 0 Ρ 5 o O O o φ rt rt 1 rt rt rt rt rt ζη z (3 ο Ο β o o o Q X rt rt -Η rt rt rt rt rt 0 »0 rt Μ £ Ό 0 +3 0 Φ ώ ο rt d Ό σ> 1 «»>· to 1 β ω Ρ Iso W 2 W 2 Ό Ρ Ό 2 s rt g ιΰ rt p β 0 xi ώ 0 xi Xh ιΰ 6 d β 0 β β υ Ή ϋ 0 rt rt rt rt rt rt rt 4-> Η Μ β P rt P Ό rt P Φ 0 0 0 Φ 0 0 Φ 0 0 Ο ω 0 Μ-» ϋ tn 0 P tn 0 ιΰ & d Oi d Ch μ ΟΙ Ρ P Oi Φ to 0 β Η β 0 2 rt P g rt Ή •Η Φ rt s rt P 2 rt χί § 0 xi g O β β 0 υ tc W υ W o tn tn destruction of the plant

Claims (5)

1. A chloracetanllide of the general formula 1 in which R^, Rg and Rg each represents a hydrogen atom, an 5 alkyl group containing 1 to 4 carbon atoms, a halogen atom or a trifluoromethyl group, R^ represents an alkyl group containing 1 to 6 carbon atoms and n represents 1, 2 or 3.

2. A compound as claimed in claim 1, wherein R^ and Rg each represents an alkyl group containing 1 to 4 carbon atoms, Rg 10 represents a hydrogen atom, R^ represents an alkyl group containing 1 to 4 carbon atoms and n represents 1 or 2.

3. Chloracetic acid /N-(3,6-dioxaheptyl)-2, 6-dimethylanilide7. 4. -80 S 7 - 27 56. A pack as claimed in claim 55, wherein the compound of the general formula 1 is a compound as claimed in claim 2. 57. A pack as claimed in claim 55, wherein the compound of the general formula 1 is the compound claims in any one of

4. Chloracetic acid /N-(3,6-dioxaoctyl)-2-methylanilide7. - 19 5. Chloracetic acid (3,6-dioxaheptyl)-anilide7. 6. Chloracetic acid fiH-(3,6-dioxaheptyl)-2,6-diethylanilide7. 7. Chloracetic acid /N-(3,6-dioxaheptyl)-2-jnethyl-anilide7. 5 8. Chloracetic acid /^-(3,6-d±oxaoctyl)-2,6-dlmethylanilide7. 9. Chloracetic acid ^7,6-diethyl-N-(3,6-dioxaoctyl)-anilide7. 10. Chloracetic acid /7-chloro-N-(3,6-dioxaoctyl)-6methylanilide?. 10 11. Chloracetic acid ^/2-chloro-N-(3,6-dioxaheptyl)-6methy1ani1ide7. 12. Chloroacetic acid /3., 6-dimethyl-N-(3,6,9-trioxadecyl) anilide7. 13. Chloracetic acid /^G-diethyl-N-Ofe^-trioxadecyl)15 anilide7. 14. Chloracetic acid /7-methyl-N-(3,6,9-trioxadecyl)-anllide7. 15. Chloracetic acid /3, 6-dimethyl-N-(3,6,9,12-tetraoxatetradecyl)-anilide?. - 20 16. Chloracetic acid /2, 6-dimethyl-N-( 3,6,9-trioxaun-decy 1)anilide7· 17. Chloracetic acid /2-ethyl-6-methyl-N-(3,6-dioxa-heptyl)anilide7. 5 18. A process for the manufacture of a compound of the general formula 1 given in claim 1, in which R^, R 2 , Rg, R 4 and n have the meanings given in claim 1, wherein an aniline of the general formula 11 NH~ (11) 10 in which Rg, R 2 and Rg have the meanings given above, is reacted with a compound of the general formula 111 X—CH 2 CH 2 —(OCH 2 CH 2 ) n —0R 4 (111) in which R 4 and n have the meanings given above and X represents a hydroxyl group, a halogen atom or a 4—CHg—CgH 4 —S0 2 —0— group, the reaction when X represents a hydroxyl group being carried out under pressure and when X represents a halogen atom or a 4—CHg—CgH 4 ~—S0 4 —0— group being - 21 480S7 carried out at a temperature within the range of from 20 to 200°C, and the resulting reaction product of the general formula IV 5 in which R^, R 2 , Rg, R^ and n have the meanings given above, is reacted in the presence of an acid acceptor with chloracetyl chloride. 19. A process as claimed in claim 18, wherein the molar weight ratio of the aniline of the general formula 11 to the compound 10 of the general formula III is within the range of from 2:1 to 3:1. 20. A process as claimed in claim 18 or 19, wherein, when X represents a hydroxyl group, the reaction with the compound of the general formula 111 is carried out in the presence of 15 water and the catalyst, 21. A process as claimed in claim 20, wherein the catalyst is a nickel catalyst. - 22 22. A process as claimed In claim 18 or 19, wherein, when X represents a halogen atom or a 4-CHg-CgH 4 -SOg—O- group, the reaction with the compound of the general formula 111 is carried out in the presence of an inert solvent. 5 23. A process as claimed in any one of claims 18 to 22, wherein the reaction between the product of the general formula IV and the chloracetyl chloride either these reactants are used in equimolar quantities or the chloroacetyl chloride is used in excess. 10 24. A process as claimed in any one of claims 18 to 23, wherein the reaction with the chloracetyl chloride is carried out in the presence of an organic solvent at a temperature within the range of from —10 to 105°C. 25. A process as claimed in claim 18 conducted substantially 15 as described herein. 26. A process as claimed in claim 18, conducted substantially as described in Example 1 herein. 27. A herbicidal preparation which comprises a compound of the general formula 1 given in claim 1, in which R^, Rg, Rg, 2o R 4 and n have the meanings given in claim 1, in admixture or conjunction with a suitable carrier. 28. A herbicidal preparation which comprises a compound as - 23 claimed in claim 2, in admixture or conjunction with a suitable carrier. 29. A herbicidal preparation which comprises the compound claimed in any one of claims 3 to 17, in admixture or 5 conjunction with a suitable carrier. 30. A preparation as claimed in any one of claims 27 to 29, which is in the form of a powder, a strewable preparation, granules, a solution, an emulsion or a suspension. 31. A preparation as claimed in any one of claims 27 to 30, 10 containing a single compound of the general formula 1. 32. A preparation as claimed in any one of claims 27 to 30, containing two or more compounds of the general formula 1. 33. A preparation as claimed in any of claims 27 to 32, which also contains one or more active substances selected 15 from plant protecting agents, pest combating agents and herbicides other than compounds of the general formula 1. 34. A preparation as claimed in any one of claims 27 to 33, wherein the total amount present of active substance or substances is approximately 5 to 95% by weight. 20 35. A preparation as claimed in any one of claims 27 to 34, containing a single surface-active agent in an amount of up to 20% by weight. - 24 36. A preparation as claimed in any one of claims 27 to 34, containing two or more surface-active agents in a total amount of up to 20% by weight. 37. Any one of the herbicidal preparations as claimed in 5 claim 27 and substantially as described in Example 2 or 3 herein. 38. A method of protecting a living plant against weeds, wherein the area in the vicinity of the living plant is treated with a compound of the general formula 1 given in 10 claim 1, in which R 2 , R 3 , R^ and n have the meanings given in claim 1. 39. A method as claimed in claim 38, wherein the area is treated with a compound as claimed in claim 2. 40. A method as claimed in claim 38, wherein the area is 15 treated with the compound claimed in any one of claims 3 to 7. 41. A method as claimed in claim 38, wherein the area is treated with a herbicidal preparation as claimed in any of claims 27 to 37. 42. A method as claimed in any one of claims 38 to 41, 20 wherein a single compound of the general formula 1 is used for the treatment in an amount within the range of from 0.5 to 5 kg per hectare. - 25 43. A method as claimed in any one of claims 38 to 41, wherein two or more compounds of the general formula 1 are used for the treatment in a total amount within the range of from 0.5 to 5 kg per hectare. 5 44. A method as claimed in claim 38, conducted substantially as described in Example 3 herein. 45. A method of protecting a crop area against weeds, wherein the crop area is treated with a compound of the general formula 1 given in claim 1, In which Rg, Rg, Rg, R^ 10 and n have the meanings given in claim 1. 46. A method as claimed in claim 45, wherein the crop area is treated with a compound as claimed in claim 2. 47. A method as claimed in claim 45, wherein the crop area is treated with the compound clained in any one of claims 3 15 to 17. 48. A method as claimed in claim 45, wherein the crop area is treated with a herbicidal preparation as claimed in any one of claims 27 to 37. 49. A method as claimed in any one of claims 45 to 48, 20 wherein a single compound of the general formula 1 is used for the treatment in an amount within the range of from 0.5 to 5 kg per hectare. 26 50. A method as claimed In any one of claims 45 to 48, wherein two or more compounds of the general formula 1 are used for the treatment in a total amount within the range of from 0.5 to 5 kg per hectare. 51. A method as claimed in any one of claims 45 to 50, wherein the crop is a cotton, ground-nut, rape, kale, cauliflower, soya bean, pea, sugar beet, spinach or lettuce crop. 52. A method of regulating the growth of a living plant, wherein the living plant is treated with a compound of the general formula 1 given in claim 1, in which R^, Rg, Rg, R^ and n have the meanings given in claim 1. 53. A method as claimed in claim 52, wherein the plant is treated with a compound as claimed in claim 2. 54. A method as claimed in claim 52, wherein the plant is treated with the compound claimed in any one of claims 3 to 17, 55. A pack which comprises a compound of the general formula 1 given in claim 1, in which R^, Rg, Rg, R^ and n have the meanings given in claim 1, together with instructions for its use as a herbicide and/or for regulating the growth of a living plant.

5. Claims 3 to 17.