CA1100996A - Herbicidally active chloracetanilides, a process for their manufacture and their use - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

Herbicidally active chloracetanilides of the formula I

Description

~ 0~ 6 ~ ~
The present invention is concerned with new herbicidally active chloracetanilides, w~th a process for the manufacture of these compounds and also with their use~
Halogeno-acetanilide derivatives having a herbicidal action are already known (see United States Patent Specification No. 3,547,620). Howevert they have only a narrow range of action and their action is strongly dependent on the soil.
The prohlem 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 ls solved in accordance with the present invention by the compounds of the general formula I, as defined below.
The present invention accordingly provides compounds of the general formula I

oH2oH2 (~2CH2)n~R4 / \ G~H

~0 ~ 2 in which Rl, 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 Rl, R2 and R3 may be the same or different.
The compo~mds 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, ~llium, Solanum, 99~;

Senecio, Matricarla, Galium, Polygonum, Trifolium, Escholtzia, .:
Di~italis, Phacella, Sorghum, Echinochloa, Setaria, Digitaris, Cyperus, Poa, Agrostls, sromus~ Lolium, Phleum, Dactylis and Festuca.
For combating weeds there are generally used applica-tion quantities within the range of from 0.5 kg of active substance per hectare to 5 kg of acti~e substance per hectare.
The aCtiYe 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, kale, cauliflower, soya bean, pea-, sugar beet, spinach and lettuce crops. When two or more compounds of the general formula I are used the range of 0.5 to 5 kg per hectare refers of course to the total amount appIied of these compounds.
The active compounds o~ the present invention have a further advantage in that they also exhibit growth-regulating properties.
As the further technically valuable changes in the de~elopment of plants caused by the compounds of the present :~ :
inventlon there may be mentioned, for exam.ple, 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 I, in admixture or con~unction with a suitable carrier.
The preparation may of course contain one or more compounds of the general formula I. ~ .
The present invention further provides a method of protecting a living plant against weeds, wherein the area in the vicinity of the Iiving plant is treated with a compound of the - ~ . : -, . .. .. . .

general formula I.
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 I.
The present invention further provides a method of reyulating the growth of a living plant, wherein the liviny plant is treated with a compound of the general formula I.
The present invention further provides a pack which comprises a compound of the yeneral formula I toyether with instructions for its use as a herbicide and/or for regulatiny the yrowth 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 protectiny or pest-combating agents may be added depending on the purpose desired.
If it is lntended to broaden the range of ac-tion other herbicides may also be added. As suitable herbicidally active co-components there may be mentioned, for example, active substances belonging to the groups of triazines, aminotriazoles, anllides, diaziDes, uracils, aliphatic carboxylic acids and halogeno-carboxyllc acids, substituted benzoic acids and aryloxy-carboxylic acids, hydrazides, amides, nitriles, esters of such carboxylic acids, carbamic acid esters and thiocarbamic acid esters, ureas, l,3,6-trichlorobenzyloxy--propanil and thiocyan-ate-containing agents. Among other additives there are to be understood, for example, non-phytotoxic 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 I or mixtures thereof are advantageously used in the form of herbicidal preparations, for example powders, strewable preparations, ` ~ :

granules, solutions, emulsions or suspensions, wi-th the addition Qf 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 ~ractions.
As solid carriers there are suitable, for example, mineral earths for example tonsil, sllica gel, talcurn, kaolin, attaclay, limestone and silicic acid, and vegetable products, for example meals.
As surface-active agents there may be mentioned, for example, calcium lignin sulphonate, polyoxyethylene alkylphenol ethers, naphthalene sulphonic acids an~ salts thereof, phenol sulphonic acids and salts thereof, formaldehyde condensates, fatty alcohol sulphates and also substituted ben~ene 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(5), approximately 95 to --5~ by weight of li~uid or solid carrier and, if desired, also up to 20% by wei~ht of sur~ace-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 o~ so called microgranules.
As substituents represented by Rl , R2 and R3 in the general formula I there may be mentioned, for example, methyl, .:

ethyl, n-propyl, isopropyl, _-butyl, sec.-butyl, isobutyl, tert.-butyl, fluoro, chlo.ro, bromo, iodo and trifluoromethyl substituents.
The symbol R4 may represent, for example, a methyl ethyl, propyl, isopropyl, n-butyl, sec.-butyl, isobutyl, tert.-butyl, n-pentyl or n-hexyl group.
Among the compounds of the present invention that are dist~nguished-by an outstanding action are especially those of the general formula I in which Rl and R2 have identical :
or different meanings and each represents an alkyl group containing 1 to 4 carbon atoms, R3 represents a hydrogen atom, R4 represents an alkyl group containing l to 4 carbon atoms and ~
n represents the number 1 or 2. :
The hitherto unknown compounds of the yeneral formula I 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 I, wherein an aniline of the general formula II

R~
: 1 '

2 (I~

J~R2 ~3 in which Rl, R2 and R3 have the meanings given abovej 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 III
X-CH2CH2-(OCH2CH2)n-OR4 (III), in which R4 and _ have the meanings given above and X represents a hydroxyl group, a halogen atom or a 4-CH3-C6H~-SO2-O- group, the reaction when X represents a hydroxyl group being carried out : -6-unaer 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-C6~4-SO2-O- group being carried out at a temperature within the range o~ from 20 to 200C, 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

Rl ' R ' ~ aH2~2~ ~2~2~n 4 ~ ~ ~ (IV) .
in which Rl, R2, R3, R4 and _ have the meanings given above, is reacted wi-th chloracetyl chloride inthe 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 carbonate, potassium carbonate or magnesium oxide, and, if desired, of an organic solvent at a temperature within the range of from -lO to 105C. 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 , ~ -7-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-diox ept~ 2,6-dimeth~lanilide].
A solution of 60.50 gm (0.5 mole) o 2,6-dime~hyl-aniline and 68.50 gm (0.25 mole) of (para-tolyl)-(1,4,7-trioxa-octyl)-sulphone in 100 ml of toluene was heated for 20 hours under reflux. After cooling, water and 25 ml of 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-dioxa-heptyl)-2,6-dimethylaniline having a boiling interval of 119 -131~C (0.~ Torr) was obtained.
Yie~d: 32.44 gms = 58.1% of the theoretical yield.
Into a solution of 11.15 gms (0.05 mole) of N-(3,6-dioxaheptyl)-2,6-dimethylàniline in 50 ml of ethyl acetate were introduced 13.82 gms (0.1 mole~ of anhydrous potassium carbonate. There were introduced into the stirred suspension dropwise at 25 - 30C whi~e cooling with ice 11.29 gms (0.1 mole) -of chloracetyl chlorlde, 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 agitatlon 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.
Yield: 12.23 gms (= 81.6~ of the theoretical yield) of chloracetic acid ~N-(3,6-dioxaheptyl)-2/6-dimethyl-anilide].

nD = 1.5250.
The follow1ng compounds of the present invention can be prepared in an analogous manner.
Name of the compound Physical constant Chloracetic acid [N-~3,6-dioxaoctyl)- 20 0 2-methylanilide] nD = 1.51 8 Chloracetic acid [N-(3,6-dioxa- 20 heptyl)-anilide] nD = 1.5260 Chloracetic acid [2,6-diethyl~N- 20 _ 4 (3,6-dioxaheptyl)-anilide] nD - 1.521 Chloracetic acid [N-(3,6-dioxa- 20 _ 2 2 heptyl)-2-methylanilide] nD - 1-5 1 Chloracetic acid [N-(3,6-dioxa- n20 - 1 5200 octyl)-2,6-dimethylanilide] D
Chloracetic acid 12,6-diethyl~N- 20 - 1 5176 (3,6-dioxaoctyl)-anilide~ D
ChIoracetic acid ~2-chloro-N- 20 - 1 5252 (3,6-dioxaoctyl)-6-methylanilide] D
Chloracetic acid [2-chloro-N- 20 - 1 5315 (3,6-dioxaheptyl)-6-methylanilide] n Chloracetic acid [N-(3,6-dioxa- n20 - 1 5092 octyl)-2-methylanilide] D
Chloracetic acid [2,6-dimethyl- n20 - 1 5208 N-~3,6,9-trioxadecyl)-anilide] D
Chloracetic acid l2,6-diethyl-N- n20 - 1 5190 (3,6,9-trioxadecyl)-anilide] D
Chloracetic acid I2-methyl-N- 20 ~ 1 5200 (3,6,9-trioxadecyl)-anilide] nD
Chloracetic acid [2,6-dimethyl- 20 N-(3,6,9,12-tetraoxatetradecyl)- n = 1.5104 anilide] D
Chloracetic acid [2,6-dimethyl- n20 = 1 5140 N-(3,6,9-trioxaundecyl)-anilide] D
Chloracetic acid [2-ethyl-6-methyl- n20 - I 5225 N-(3,6-dioxaheptyl)-anilide] D
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 li~res of water : ~ _g_ 9~

per hectare, on Dig _aria s. and Echinochloa c.g. as test plants by the pre-emergence method. Three weeks after the treatment the results thereo~ were evaluated and the results expressed by a numerical scale extending from 0 to 4, the value 0 representing no action and the val~le 4 representing destructlon of the plant. As can be seen from the Table destruction of the test plants was achieved.
Compound of the invention Digitaria Echinochloa sangllln curs alis ~_lli 1 0 _ Chloracetic acid ~N-(3,6-dioxa~
heptyl)-2,6-dimethylanilide] 4 4 -Chloracetic acid [2,6-diethyl-N-(3,6-dioxaheptyl)-anilide] 4 4 Chloracetic acid [N-(3,6 dioxaheptyl)-2-methylanilide] 4 4 Chloracetic acid ~N-(3,6-dioxa-octyl)-2,6-dimethylanilide~ 4 4 Chloracetic acid [2,6-dimethyl N-(3,6-dioxaoctyl)-anilide] 4 4 Chloracetic acid ~2-chloro-N-(3,6-dioxaoctyl)-6-methylanillde] 4 4 Chloracetic acid l2-chloro-N-(3,6-dioxaheptyl)-6-methyl-anilide] 4 4 Chloracetic acid IN-(3,6-dioxaoctyl)-2-methylanilide] 4 4 Chloracetic acid [2,6~dimethyl-N-(3,6,9-trioxadecyl)-anilide] 4 4 Chloracetic acid [2,6-diethyl-N-(3,6,9-trioxadecyl~-anilide] 4 4 Chloracetic acid ~2-methyl-N-(3,6,9-trioxadecyl)-anilide] 4 4 Chloracetic acid ~2,6-dimethyl~
N-(3,6,9,12-tetraoxatetradecyl)-anilide] 4 4 Chloracetic acid [2,6-dimethyl-N-(3,6,9-trioxa~ndecyl)-anilide] 4 4 Chloracetic acid [2-ethyl-6- ~ -methyl-N-(3,6-dioxaheptyl)-anilide] 4 4 g96 ~ntreated o o 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 exhiblted a comparatively much weaker action which, furthermore, was strongly dependent upon the type of soil. The results are expressed by a numerical scale e~tending from 0 to 10; the value 0 representing destruction of the plant and the value 10 representing no damage. ~ ;

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Claims (60)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A chloracetanilide of the general formula I

(I) in which R1, 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.

2. A compound as claimed in claim 1, wherein R1 and R2 each represents an alkyl group containing 1 to 4 carbon atoms, R3 represents a hydrogen atom, R4 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-dimethyl-anilide].

4. Chloracetic acid [N-(3,6-dioxaoctyl)-2-methyl-anilide].

5. Chloracetic acid [N-(3,6-dioxaheptyl)-anilide].

6. Chloracetic acid [N-(3,6-dioxaheptyl)-2,6-diethyl-anilide].

7. Chloracetic acid IN-(3,6-dioxaheptyl)-2-methyl-anilide].

8. Chloracetic acid [N-(3,6-dioxaoctyl)-2,6-dimethyl-anilide].

9. Chloracetic acid [2,6-diethyl-N-(3,6-dioxaoctyl)-anilide].

10. Chloracetic acid [2-chloro-N-(3,6-dioxaoctyl)-6-methylanilide].

11. Chloracetic acid [2-chloro-N-(3,6-dioxaheptyl)-6-methylanilide].

12. Chloracetic acid [N-(3,6-dioxaoctyl)-2-methyl-anilide].

13. Chloracetic acid [2,6-dimethyl-N-(3,6,9-trioxa-decyl)-anilide].

14. Chloracetic acid [2,6-diethyl-N-(3,6,9-trioxa-decyl)-anilide].

15. Chloracetic acid [2-methyl-N-(3,6,9-trioxadecyl)-anilide].

16. Chloracetic acid [2,6-dimethyl-N-(3,6,9,12-tetra-oxytetradecyl)-anilide].

17. Chloracetic acid [2,6-dimethyl-N-(3,6,9-trioxaun-decyl)-anilide].

18. Chloracetic acid [2-ethyl-6-methyl-N-(3,6-dioxa-heptyl)-anilide].

19. A process for the manufacture of a compound of the general formula I given in claim 1, in which R1, R2, R3, R4 and n have the meanings given in claim 1, wherein an aniline of the general formula II

(II) in which R1, R2 and R3 have the meanings given above, is reacted with a compound of the general formula III
X-OH2CH2-(OCH2CH2)n-OR4 (III), in which R4 and n have the meanings given above and X represents a hydroxyl group, a halogen atom or a 4-CH3-C6H4-SO2-O- group, the reaction when X represents a hydroxyl group being carried out under pressure and when X represents a halogen atom or a 4-CH3-C6H4-SO2-O- group being carried out at a temperature within the range of from 20 to 200°C , and the resulting reaction product of the general formula IV

(IV) in which R1, R2, R3, R4 and n have the meanings given above, is reacted in the presence of an acid acceptor with chloracetyl chloride.

20. A process as claimed in Clalm 19, wherein the molar weight ratio of the aniline of the general formula II to the compound of the general formula III is within the range of from 2:1 to 3:1.

21. A process as claimed in Claim 19, wherein when X
represents a hydroxyl group, the reaction with the compound of the general formula III is carried out in the presence of water and a catalyst.

22. A process as claimed in Claim 21, wherein the catalyst is a nickel catalyst.

23. A process as claimed in Claim 19 or 20, wherein when X represents a halogen atom or a 4-CH3-C6H4-SO2-O-group, the reaction with the compound of the general formula III is carried out in the presence of an inert solvent.

24. A process as claimed in Claim 19, 20 or 21, wherein in the reaction between the product of the general formula IV and the chloracetyl chloride either these reactants are used in equi-molar quantities or the chloroacetyl chloride is used in excess.

25. A process as claimed in Claim 19, 20 or 21, wherein the reaction with the chloroacetyl chloride is carried out in the presence of an organic solvent at a temperature within the range of from -10 to 105°C.

26. 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 I given in Claim 1, in which R1, R2, R3, R4 and n have the meanings given in Claim 1.

27. A method as claimed in Claim 26, wherein the area is treated with a compound as claimed in Claim 2.

28. A method as claimed in Claim 26, wherein the area is treated with a compound as claimed in Claim 3 or 4.

29. A method as claimed in Claim 26, wherein the area is treated with a compound as claimed in Claim 5 or 6.

30. A method as claimed in Claim 26, wherein the area is treated with a compound as claimed inClalm 7 or 8.

31. A method as claimed in Claim 26, wherein the area is treated with a compound as claimed in Claim 9 or 10.

32. A method as claimed in Claim 26, wherein tile area is treated with a compound as claimed in Claim 11 or 12.

33. A method as claimed in Claim 26, wherein the area is treated with a compound as claimed in Claim 13 or 14.

34. A method as claimed in Claim 26, wherein the area is treated with a compound as claimed in Claim 15 or 16.

35. A method as claimed in Claim 26, wherein the area is treated with a compound as claimed in Claim 17 or 18.

36. A method as claimed in Claim 26, wherein a single compound of the general formula I is used for the treatment in an amount within the range of from 0.5 to 5 kg per hectare.

37. A method as claimed in Claim 26, wherein two or more compounds of the general formula I are used for the treatment in a total amount within the range of from 0.5 to 5 kg per hectare.

38. A method of protecting a crop area against weeds, wherein the crop area is treated with a compound of the general formula I given in Claim 1, in which R1, R2, R3, R4 and n have the meanings given in Claim 1.

39. A method as claimed in Claim 38, wherein the crop area is treated with a compound as claimed in Claim 2.

40. A method as claimed in Claim 38, wherein the crop area is treated with a compound as claimed in Claim 3 or 4.

41. A method as claimed in Claim 38, wherein the crop area is treated with a compound as claimed in Claim 5 or 6.

42. A method as claimed in Claim 38, wherein the crop area is treated with a compound as claimed in Claim 7 or 8.

43. A method as claimed in Claim 38, wherein the crop area is treated with a compound as claimed in Claim 9 or 10.

44. A method as claimed in Claim 38, wherein the crop area is treated with a compound as claimed in Claim 11 or 12.

45. A method as claimed in Claim 38, wherein the crop area is treated with a compound as claimed in Claim 13 or 14.

46. A method as claimed in Claim 38, wherein the crop area is treated with a compound as claimed in Claim 15 or 16.

47. A method as claimed in Claim 38, wherein the crop area is treated with a compound as claimed in Claim 17 or 18.

48. A method as claimed in Claim 38, wherein a single compound of the general formula I is used for the treatment in an amount within the range of from 0.5 to 5 kg per hectare.

49. A method as claimed in Claim 38, wherein two or more compounds of the general formula I are used for the treatment in a total amount within the range of from 0.5 to 5 kg per hectare.

50. A method as claimed in Claim 38, wherein the crop is a cotton, ground-nut, rape, kale, cauliflower, soya bean, pea, sugar beet, spinach or lettuce crop.

51. A method of regulating the growth of a living plant, wherein the living plant is treated with a compound of the general formula I given in Claim 1, in which R1, R2, R3, R4 and n have the meanings given in Claim 1.

52. A method as claimed in Claim 51, wherein the plant is treated with a compound as claimed in Claim 2.

53. A method as claimed in Claim 51 , wherein the plant is treated with a compound as claimed in Claim 3 or 4.

54. A method as claimed in Claim 51, wherein the plant is treated with a compound as claimed in Claim 5 or 6.

55. A method as claimed in Claim 51, wherein the plant is treated with a compound as claimed in Claim 7 or 8.

56. A method as claimed in Claim 51, wherein the plant is treated with a compound as claimed in Claim 9 or 10.

57. A method as claimed in Claim 51, wherein the plant is treated with a compound as claimed in Claim 11 or 12.

58. A method as claimed in Claim 51, wherein the plant is treated with a compound as claimed in Claim 13 or 14.

59. A method as claimed in Claim 51, wherein the plant is treated with a compound as claimed in Claim 15 or 16.

60. A method as claimed in Claim 51, wherein the plant is treated with a compound as claimed in Claim 17 or 18.