FR2488782A1 - ANTIDOTES COMPOSITIONS OF HERBICIDES CONTAINING N- (SUBSTITUTED ACETYL) -N- (4-METHYL-2-PENTANON-4-YL) -AMIDES - Google Patents

Abstract

THE INVENTION RELATES TO A HERBICIDE COMPOSITION CONSISTING OF AT LEAST ONE THIOLCARBAMATE HERBICIDE AND AN ANTIDOTE TO THIS COMPOUND CORRESPONDING TO GENERAL FORMULA I (CF DRAWING IN BOPI) OR R IS A HYDROGEN, AN ALCOHOL HAVING FROM 1 TO 4 OR ONE CARBON ATOMS ALKENYL HAVING 2 TO 5 CARBON ATOMS, R IS A HYDROGEN, A CHLORINE OR A CHLOROALCOYL, R IS A CHLORINE OR A CHLOROALCOYL, WITH THE SPECIFICATION THAT IF R AND R REPRESENT CHLORINE, R IS A HYDROGEN, AS WELL AS A METHOD FOR CONTROLLING PLANT PARASITES AND A PROCEDURE FOR PROTECTING CROPS.

Description

The present invention relates to compositions

  Herbicide antidotes containing N- (substituted acetyl) -

  N- (4-methyl-2-pentanon-4-yl) amides. More specifically

  the invention relates to antidote compositions of herbicides comprising at least one active compound as a herbicide as defined below and an antidote for this compound corresponding to the general formula (I)

R2 R CH3

c c

CH-C-N-C-CH-CH (I)

R3 O CH3 O

  R 1 is hydrogen, alkyl having 1 to 4 carbon atoms or alkenyl having 2 to 5 carbon atoms, R 2 is hydrogen, chloro or chloroalkyl, R 3 is chloro or chloroalkyl, with accuracy that if R2 and R3 represent a chlorine,

R1 is a hydrogen.

  It is well known that a large number of

  commercially available herbicides are non

  only effective against weeds inde-

  but can also cause serious

  crop damage. This indefinable phytotoxic effect

  sirable results in a loss of crop yield.

  The phytotoxicity observed depends on the dose used,

  but it can usually be established that corresponding doses

  with a destruction effect of around 90% of

  Weeds are already causing serious malforma-

  and stunting of crops and therefore reduce

their performance.

  Of the many herbicide compounds available, thiolcarbamates alone or mixed with other herbicides have achieved a relatively high degree of commercial success. So it is very unfortunate

  that among the herbicides containing N, N-dialkoyl-S-

  alkyl-thiolcarbamates, only the least active compound, N, N-diisobutylS-ethyl-thiolcarbamate (Sutan) was found to be a selective herbicide. For example, the

  N, N-dipropyl-S-ethyl-thiolcarbamate (EPTC) which is considered

  It is notoriously more effective, is rather phytotoxic for cultivated plants, and can thus end up for example in the case of maize at a loss of about 30 to 50% of yield.

  Previous attempts to solve this problem

  bleme involve a treatment of plants with certain antagonistic agents. Thus, according to the German patent applications published under No. 2 218 097 and

  2,350,800, the phytotoxicity of

  to the thiolcarbamates by adding 0.0001 to 30% by weight of a N, N-disubstituted dichloroacetamide derivative to the active compound as a herbicide and carrying out the treatment with a combination of said herbicides and

  dichloroacetamide derivatives. The US patents

  Nos. 3,131,509 and 3,702,759 disclose the use of 1,8-naphthalic acid or a salt or ester thereof as an antagonist. However, these antagonists

not been very successful.

  It has surprisingly been found that the phytotoxicity of herbicides containing thiolcarbamates can be effectively eliminated or reduced by using an antidotally effective amount of an N- (substituted acetyl) -N- (4-methyl-2-pentanon) 4-yl) -amide of the general formula I o R1, R2 and R3 are as defined above.

  In the description above and from one end to

  the other of the description, the term "alkyl having

  1 to 4 carbon atoms "describes hydro groups

  saturated straight or branched chain aliphatic carbon containing 1 to 4 carbon atoms, for example methyl, ethyl, n- or isopropyl, n-hexyl, etc. The term "alkenyl having from 2 to 5 carbon atoms

  carbon "is used here to describe hydro-

  straight or branched chain unsaturated aliphatic carbon having 2 to 5 carbon atoms, for example vinyl, allyl, isopropenyl, etc. The term "antidote" or "effective amount as an antidote" is used to describe the effect that tends to oppose the normal adverse reaction that

  the herbicide could otherwise produce.

  The compounds of the general formula I are known to those skilled in the art and may, for example, be prepared by analogy with the processes illustrated by the

Examples 1 to 4 below.

  Herbicides containing thiolcarbamates, which can preferably be combined with antidotes

  of general formula I are N, N-dialkyl derivatives.

  S-alkyl-thiolcarbamate of general formula II R4

\ N-C-S-R (II)

/ II 6

  R 5 0 o R and R 5 may be the same or different and may be an alkyl group having 1 to 8 carbon atoms, or R 4 and R 5 together form an alkylene group having 4 to 6 carbon atoms, R 6 is an alkyl having 1 to 6 carbon atoms or

  alkenyl having 1 to 4 carbon atoms.

  The compositions according to the invention can be applied in any convenient form. They can be formulated into emulsifiable concentrates, wettable powders, powders, granules or any other practical form. Can also

  formulate herbicides and antidotes separately.

  The amount of antidote present in the compositions according to the invention may vary from about 0.001 to 50% by weight, preferably from 0.01 to 50% by weight, relative to the active compound as herbicide. The exact amount of the antidote compound is generally determined on economic grounds to obtain the most effective amount that can be used. It should be understood that a non-phytotoxic amount of herbicidal compound is employed in the herbicidal compositions

here described.

  The compositions may also contain classically inert solid or liquid carriers

  employed in the preparation of promotional compositions

  plant protection. The total amount of the compound

  active as a herbicide and antidote in the

  according to the invention is preferably from 10 to

  % by weight relative to the total weight of the composition

  sition. The present invention also provides a

  method for controlling weeds

  both to apply to their habitat an active amount like

  herbicide of a composition according to the invention.

  According to one embodiment of the method of the invention, a non-phytotoxic amount of an active compound is mixed as a herbicide with a selected herbicide and, in a suitable formulation, it is incorporated in the soil before or after the planting of the seeds. . It should be understood, however, that separate formulations of the herbicide and antidote may also be employed and incorporated into the soil one after the other. Of

  more, the seeds of the crops can be treated

  same with a suitable formulation of an antidote of

  general formula I and then plant them in a pre-existing soil

  treated with the herbicide, or plant in soil not yet treated with the herbicide and subsequently treated with the herbicide. The disinfection of seeds with the antidotes of general formula I

  reveals to be the preferred mode of application.

  The invention also comprises a method of protecting crops against damage caused by an active compound as a herbicide involving applying to plants an effective antidotal amount of an antidote of general formula I.

  More specific details of the

  in the following examples, which should not be

  limit the scope of the invention in any way.

  Preparation of compounds of general formula I

Example 1

  N- (2,2-dichloroacetyl) -N- (4-methyl-2-

  pentanon-4-yl) -amide In a suspension of 0.1 mol of 4-amino-4-methyl-2-pentanone oxalate in benzene, a 40% aqueous solution is added dropwise at 0 ° to 150 ° C. containing 0.4 moles of sodium hydroxide, and then 0.15 moles of dichloroacetyl chloride are added dropwise. When the addition is complete, the reaction mixture is stirred at room temperature

  for 2 h, then the precipitate is filtered off.

  The benzene and aqueous phases are separated, the benzene phase is washed neutral with water, the benzene is distilled off and the residue is recrystallized from hexane. After recrystallization,

product melts at 43 C.

  Analysis: Calculated N = 6.09%, C1 = 30.82%;

Found: N = 5.97% Cl = 30.57%.

  By gas chromatography, only one peak is obtained, which is different from the characteristic peaks of the starting compounds, that is to say

we get a uniform product.

Example 2

  N- (2,2-dichloroacetyl) -N-allyl- (4-methyl-2-

  pentanon-4-yl) -amide Starting from allyl amine, mesityl oxide and oxalic acid or 4-amino-4-methyl-2-pentanone oxalate, bromide and 'allyle and a

  acid binding agent, N-oxalyl-N-allyl-N-

  (4-methyl-2-pentanon-4-yl) -amide. In a suspension of

  0.1 mole of N-oxalyl-N-allyl-N- (4-methyl-2-pentanon-4-)

  In a benzene solution, a 40% aqueous solution containing 0.4 mol of sodium hydroxide is added dropwise while stirring at 0.degree. to 5.degree.

  add dropwise 0.15 mole of dichloromethane

  acetyl. The reaction mixture is stirred at room temperature, the precipitate is filtered off and the benzene and aqueous phases are separated. The benzene phase is washed neutral with water, dried over anhydrous sodium sulphate and the benzene is separated off.

  distillation. The residue can be used without further purification.

  fication. Analysis: Calculated: N = 5.26%, Cl = 26.64%; Found: N = 5.38%, Cl = 25.97%.

Example 3

  N- (3-chloropropionyl) -N- (4-methyl-2-pentanon-

  In a suspension of 0.1 mol of 4-amino-4-methyl-pentanone oxalate in benzene, a 40% aqueous solution containing 0.4 mol of sodium hydroxide was added dropwise. sodium, while stirring between 0 and 5 C, and then added dropwise 0.15 mole of 3chloropropionyl chloride. We then follow the process

described in Example 1.

  Analysis: Calculated: N = 6.81%, Cl = 17.24%;

Found: N = 7.05%, Cl = 17.10%.

Example 4

  N- (2,2-dichloroacetyl) -N-ethyl-N- (4-methyl-2-

  pentanon-4-yl) -amide Starting from ethylamine, mesytyl oxide and oxalic acid or 4-amino-4-methyl-2-pentanone oxalate and sodium iodide. 'ethyl in

  the presence of an acid binding agent, the N-oxylyl

  N-ethyl-N- (4-methyl-2-pentanon-4-yl) -amide. The resulting compound is further reacted with dichloroacetyl chloride in the presence of an acidic binder

as it is said in example 2.

  Analysis: Calculated: N = 5.51%, Cl = 27.90%;

Found: N = 5.38%, Cl = 27.47%.

  The formulations prepared from the compounds

  according to the invention are specified by the

following examples.

Example 5

  Emulsifiable concentrate Composed of Example 3 xylene

polyoxyethylene alkyl-

  % by weight by weight aryl ether 5% by weight The concentrate can easily be

  emulsified with water and applied by spraying.

Example 6

  N, N-dipropyl-S-ethyl-thiolcarbamate emulsifiable concentrate

  N- (2,2-dichloroacetyl) -N- (4-methyl-

  2-pentanon-4-yl) -amide xylene polyoxyethylene alkylaryl ether

Example 7

  % by weight% by weight% by weight% by weight Wettable powder

  N- (2,2-dichloroacetyl) -N- (4-methyl-

  2-pentanon-4-yl) -amide 70% by weight Kaolin 15% by weight active silicic acid 10% by weight fatty alcohol sulphonate 2.5% by weight sodium salt of sulphonic acid 2.5% by weight The ingredients are weighed in a ball mill and crushed for 3 hours to give the

desired formulation.

  The following examples specify the use and

  the activity of the compositions according to the invention.

  The experiments are done in a greenhouse in pots that are filled with sandy and loamy soil. In each pot 15 seeds are planted at a depth of 5 cm. The pots are kept in a greenhouse at a temperature of 20 to 30 C and watered at will. We carry out all the experiments 4 times and we

  evaluate the results on the basis of the EWRC scale

  nationally accepted. According to this scale, the note 1 means that no harmful effect is observed, while note 9 applies to a total attack.

Example 8

  Cultivated plant: but Herbicide: N, N-dipropyl-S-ethyl-thiolcarbamate (TCPS)

  prepared as emulsifiable concentrate "Eptam 6E".

  Known antidote used for comparison: N, N-diallyl-2,2-dichloroacetylamide.

  The herbicide is incorporated into the soil at a depth of

  5 cm before planting maize seeds. The experimental compounds of

  general formula (I) from emulsified concentrates

  reliable. The herbicide is used at a rate of 13 liters / ha, and the doses of antidotes tested are given in the table.

1 below.

TABLE I

  Treatment Dose of antidote (kg of active ingredient / ha)

Results at the

EWRC scale end to end

of se-

  ADTC alone 9 9 EPTC + N, N-diallyl-2,2-dichloroacetamide 1,0 4 3 EPTC + N- (2,2-dichloroacetyl) -0.44 -N- ( 4-methyl-2-pentanon-4-yl) 1.0 -2 amide 2.0 2 TABLE I (cont.) EPTC + N (3-chloropropionyl) -N-0.5 6 4 (4-methyl-2- pentanon-4-yl) - 1.0 4 3 amide 2.0 3 2 The results given in the table above clearly show that the phytotoxicity of a dose of 13 1 per hectare of TCPS, which roughly corresponds to at twice the conventional dose, is effectively reduced by the compounds of general formula I tested.

Example 9

  Cultivated plant: but Herbicide: N, N-dipropyl-S-ethyl-thiolcarbamate (TCPS)

  presented in the form of emulsifiable concentrate "Eptam 6E".

  Known antidote used for comparison: N, N-diallyl-2,2-dichloroacetamide. In this experiment, the seeds were treated with doses of 0.25, 0.50 and 1.00 kg of antidotes tested per 100 kg of seed dose. The herbicide is incorporated into the soil before planting, at a rate of 13 1 / ha. The results obtained are given in Table 2 below.

TABLE 2

  Treatment Dose of anti- Results at Sprays- disinfecote (kg / 100 scale EWRC Pulse-disinfec- kg kg of seed kg) from end to end

seeds of the se-

maine hands

TCPS - 9 9

  EPTC + N, N-diallyl-2,2-dichloro-0.5-roacetamide 1.0 TABLE 2 (continued) EPTC + N- (2,2-dichloroacetyl) - 0.25 3 2 N- ( 4-methyl-2-pentanon-O, 50 2,4-yl) -amide 1,00 2 1 EPTC + N- (3-chloropropionyl) -N-0.25 4 3 (4-methyl-2-pentanon-4- The antidote activity of the compounds of general formula I according to the invention is also clearly illustrated by the results obtained in field trials. In the field trials presented below, phytotoxicity is assessed on the basis of the EWRC international scale mentioned above. For the evaluation of the herbicidal activity another scale is used ranging from 1 to 9, where 1 represents a herbicidal action of 100%, while 9. corresponds to an effect

herbicide equal to zero.

Example 10

  Cultivated plant: but Herbicide: N, N-dipropyl-S-ethyl-thiolcarbamate (TCPS)

  presented in the form of emulsifiable concentrate "Eptam 6E".

  Weeds Tested: Echinochloa crus galli

  quence in the untreated field: 70%).

  Amaranthus retroflexus (frequency in the

untreated field: 25%).

  In the table below, "p" means that the treatment is essentially carried out as described in Example 8, "sd" means that the plants have been disinfected and that the treatment has been carried out

essentially according to example 9.

TABLE 3

  Treatment Dose of antidote (kg of active ingredient / ha) (kg of active ingredient / 100 kg of seed)

phytotoxic

quoted at the end

of

after 3 weeks

Action Herbi-

cide at the end

of

  after 3 weeks EPTC alone 8 7 1 1 EPTC + N- (2,2dichloroacetyl) -0.5 p 3 3 1 1 N- (4-methyl-2-pentanon-4-yl) - 1.0 p 3 2 1 1 amide 2.0 p 2 1 1 1 0.25 sd 3 2 1 1 0.5 sd 2 1 1 1 1.0 sd 2 1 1 1

w -

w

M H

  CD o O tb o o rj o fi Ca H o rH o rh CD rt H

O FC-

CD l o H. re Y_ (D Ca o

F0 M

CD% tn e H o \ CD% w ul F_3 Pa

P CD

o pi t CD (D Pi SJ c% Co ro

Z488782

  We get practically the same results

  replacing the EPTC with N, N-diisobutyl-S-ethyl-

  thiolcarbamate, N, N-hexamethylene-S-ethyl-thiolcar-

  bamate or N, N-diisopropyl-S- (2,3,5-trichloroallyl)

thiolcarbamate.

Claims (9)

  1. A herbicidal composition comprising at least one thiolcarbamate herbicide and an antidote for this compound corresponding to the general formula (I) R2 R 1CH3 CH-C-N-C-CH-CH3 (I) R3 0 CH3 O   or R1 is hydrogen, an alkyl having 1 to 4 carbon atoms   carbon or alkenyl having from 2 to 5 carbon atoms   B, R2 is hydrogen, chloro or chloroalkyl, R3 is chloro or chloroalkyl, with the precision that if R2 and R3 are chlorine, R1 is a hydrogen.   2. Composition according to claim 1, characterized in that it comprises as herbicide at   thiolcarbamate an N, N-dialkyl-S-alkyl derivative   thiolcarbamate of general formula II R4 N-C-S-R6 (II) R5 O   R4 and R5 may be the same or different and may be an alkyl group having 1 to 8 carbon atoms, or R4 and R5 together form an alkylene group having 4 to 6 carbon atoms, R6 is an alkyl having from 1 to 6 carbon atoms or one   alkenyl having 1 to 4 carbon atoms.   3. Composition according to one of the claims   1 and 2, characterized in that it comprises as herbicide   N, N-dipropyl-S-ethyl-thiolcarbamate, N, N-diisobutyl-S-ethyl-thiolcarbamate, thiolcarbamate   N, N-hexamethylene-S-thiolcarbamate or N, N-diisopropyl-   S- (2,3,5-trichloroallyl) -thiolcarbamate.   4. Composition according to one of the claims   1 to 3, characterized in that it comprises as anti-   N- (2,2-dichloroacetyl) -N- (4-methyl-2-pentanon)   4-yl) -amide or N- (3-chloropropionyl) -N- (4-methyl-2- pentanon-4-yl) -amide.   5. Composition according to one of the claims   1 to 4, characterized in that the antidote compound is present in an amount of 0.001 to 50% by weight of active compound as herbicide.   6. Composition according to one of the claims   1 to 5, characterized in that it also includes an inert carrier or diluent.   7. Composition according to one of the claims   1 to 5, characterized in that the total amount of the thiolcarbamate herbicide and the antidote is 90% by weight based on the total weight of the composition.   8. Control method against parasites   plants, characterized in that it consists in applying to their habitat an effective amount as herbicide   of a composition according to claim 1.   9. Method of protecting crops against   the damage caused by thiol herbicides   bamate, characterized in that it consists in applying to   plants or their seeds a non-phytosanitary   toxic, effective as an antidote to a compound of formula   general I according to claim 1.