IL38183A - Herbicidally active s-methyl n-(carbamoyloxyphenyl)thio carbamates - Google Patents

Description

Herblcldally active carbamoyl oxhphenyl thio carbamates invention oonoemed with new substituted and with their manufacture and especially their use as selective veed control agents in cultivated She activity of phenyl for example of has been Israel Patent 26696 known German it has been found that this active substance is not sufficient enough against types of The present invention provides compounds of the general formula I in which represents a lover these new compounds of the present invention are used as herbicides tile disadvantage mentioned above of the aforesaid known tiocarbamates ie overeome since they are especially suitable for the selective control of undesired types of especially among cultivated In combination with an inert vehicle the compounds of the general formula I effectively control types of especially types of for example Setarda Eohinocloa crus and the active compounds of the present invention possess a high selectivity towards cultivated especially towards plants which themselves represent types of Since millet plants often grow as undesired grasses in crops of the use of the compounde of the present invention makes it possible to control types of millet without the cultivated an extraordinary technical The activity of the active compounds of the present invention not limited to the aforesaid types of grasses but extends equally to other for dicotyledonous for example Stellaria Seneoio Matricaria Centaurea Ipomea purpurea and are also controlled by the new used as herbicides the compounds of the present invention are preferably applied at the that is to say after theplants have germinated so that an aqueous preparation of the active substanee attacks them The preparations applied to the water surface of the flooded fields of the growing When the stage is the preferred amount applied ranges from about 1 to kg of active substanee according to the present invention per hectare active substance being made up of one compound of the general formula I or a mixture of two or more compounds of the general formula It also possible to use the active compounds at the but in this case a higher amount in excess of kg of active substance per hectare must be The present invention accordingly also provides a method of protecting a living plant against wherein the area in the vicinity of a living plant is treated with a compound of the general formula The present invention further provides a method of protecting a crop area against wherein a crop area is treated with a compound of the general formula active compounds of the invention be used as preparations which take the form of the conventional herbicidal present invention accordingly further provides a herbicidal preparation which comprises a compound of the general in admixture Or conjunction with a suitable the herbicidal preparations may be in the form for spraying or dusting emulsions or Emulsions appropriate additives are especially suitable as Suitable additives for these preparations are liquid solid vehicles or diluents if for example vetting emulsifiers andor dispersing as veil as fertilizers or other Suitable liquid vehicles for petroleum fractions or other organic for example carbon dimet lformamide or Suitable solid vehicles for attaclay and other As agents there may be for cationic and for example ethoxylated alkylphenol polyglycol tributylphenyl polyglycol polyether isotrideoyl lauryl ether fatty alcohol ethylene oxide ethoxylated castor polyoxyathylene alkyl ethoxylated sorbitol esters and lauryl alcohol polyglycol ether The preparations of the present invention may be in a known for example by mixing or If the individual constituents may be mixed only shortly prior to use as is done in for in the tank mix The content of active substance which may be a single compound of the general formula I or a mixture of two or more of the general formula in a herbieidal preparation ready for use ranges advantageously from about 2 to by preferably from 15 to by referred to the weight of the In addition such preparations contain about 98 to by weight of or solid if up to about by weight of a single agent or a mixture of The active compounds of the present invention of the general formula I may be used either alone or in the form of mixtures containing several active It is possible to incorporate other herbicides with them to broaden the activity to improve the selectivity or the effect on the soil or to improve the stability towards atmospheric Especially suitable additives are those that are capable of causing a synergistic activity for example certain wetting solvents and Preferred substituents represented by in the general formula I given above of the active substances are groups containing 1 to carbon atoms and as the preferred substituents represented by there may be for The hitherto unknown active compounds of the general formula I may be manufactured by known for exmaple from the appropriate acid esters and aniline derivatives or the appropriate phenols or their salts carbamoylohlorides the presence of inorganic or organic bases or from the appropriate by hydrogenation of the nitro group to the amino for example with the use of Eaney nicke in and reactio with thioformic if desired in the presence of an inorganic or tertiary organic The present invention accordingly further provides a process for the manufacture of a compound of the general formula wherein a compound of the general formula reacted in the presence of an inorganic or organic base with an amine of the formula a compound of the general formula or a salt thereof is reacted the presence of an inorganic or organic base with a oarbamoylchloride of the general formula a compound of the general formula is catalytically reduced to the corresponding which is then reacted with a compound the general formula S if desired in the presence of an inorganic or tertiary organic In the above formulae and have the meanings given The manufacture of compounds of the present invention is exemplified in Examples 1 and 2 In a manner similar to that described la Example 1 or 2 below the following compounds of the present invention may be o melting at 104 to melting at 158 to melting at 100 to 10 melting at 114 to melting at 148 to 20 following Examples the Example 1 thiocarbamate A solution of g of ester and g of evaporated the residue was dissolved in methylene chloride and the solution with and washed successively with a dilute sodium hydroxide dilute hydrochloric water and a sodium then dried over sulphate and She initially oily residue furnished from ether 108 of theoretical of a crystalllzate melting at 101 to of While stirring and cooling to 10 to a solution of g of in 50 ml of ethyl there were simultaneously added a solution of g of chloroforoic thio phenyl ester 100 ml of ethyl acetate and a solution of g of potassium in ml of The mixture was stirred for another minutes without and the organic phase was then washed with dilute hydrochloric acid and water with the addition of The solution was dried over magnesium sulphate and filtered in ethyl acetate through neutral alumina and evaporated under g of the theoretical Melting point after recrystallization from 104 to used as one of the starting materials was prepared in the usual manner from the ester and phosgene with the addition of dimethylaniline in ethyl Example In a greenhouse the test plants listed in the Table were treated in the stage in a series of experiments with preparations eontaining compounds of the present the preparations being used such amounts that 1 kg of active substance was applied per The She preparations were evenly sprayed over the soil in the form of aqueous emulsions using 500 litres per Se control compound was likewise sprayed as anaqueous emulsion at a concentration of 1 kg of active substance per hectare using 500 litres per The results show that the preparations containing the compounds of the present invention did not damage the cultivated plants and produced a much better control of the undesired plants than did the preparation containing the known control The results are expressed by numerical scale extending from 0 to the value 0 being equivalent to total destruction and the value 10 being equivalent to no evaluation was carried out 3 weeks after the Active compound in preparation 1 2 3 4 5 6 7 8 1011 121314 invention totally destroyed undamaged 81 seed rice 2 Sinapis 3 4 vulgaris 5 Matricaria 7 evanua 8 Amarantus aparine 0 purpurea 12 Echinoohloa She test plants listed in the Table below treated in a greenhouse as described in Example expressed in the same manner as in Example are shown in the These likeise prove that the preparations containing the compounds of the present invention superio in their effect against undesired plants a compared with the preparation containing the control compound and did not damage the cultivated Active compound in preparation of this i 5 6 7 9 10 11 12 invention 10 0 0 0 0 0 0 0 0 0 0 0 0 ocarbamate 10 0 0 0 0 0 0 0 0 0 1 0 0 Control compound 1 Seed rice 2 Sinapis 3 Stellaria media 4 Senecio vulgaris 5 Matricaria 6 caule Centanrea cvanus 8 Amarantus retroflexus 9 Chrysanthemum insufficientOCRQuality

Claims (24)

1. 38183/2 What we claim 1s:- A compound of the general formula I n which R^ represents a lower alkyl group and R¾ represents a phenyl or al Kyi phenyl group.

2. A compound as claimed In claim 1 · wherein R, represents an alkyl group containing 1 to 3 carbon atoms.

3. A compound as claimed In claim 1 or 2, wherein Rg represents a phenyl , 2-methyl phenyl , 3-methyl phenyl , 3-ethyl phenyl cr4-ethyl phenyl group .

4. S-Methyl -N-[3- (N ' -methyl -N ' -phenyl carbamoyl oxy) -phenyl ]-th1ocarbamate.

5. S-Meth l -N- j 3- [N 1 -methyl -N 1 - { 41 -eth l phenyl )-carbamoyloxy]-phenyl j-t ocarbamate.

6. S-Methyl -N- 13- [ ' -ethyl - 1 - (4 * -methyl phenyl ) -carbamoyl oxy ]-phenyl j-thloearbamate.

7. S-Methyl -H- [3-(N ' -ethyl -N 1 -phenyl carbamoyl oxy )-pheny1 ]-thlocarbamate.

8. S-Methyl -N- j3~[N* -ethyl - ' - { 3 ' -methyl phenyl )-carbamoy1 ox ]-phenyl j-thlocarbamate.

9. S-Methyl -N- J 3- [N ' -eth l -N ' - ( 2 ' -methyl henyl ) -carbamo l oxy ]-phenyl J -thlocarbamate.

10. S-Methyl -N- [3- (N ' - sopropyl -N ' -phen l -carbamoyl oxy ) -phen l ]-thlocarbamate.

11. S-Methyl -N- |3- [N ' -methyl -N · - (3 · -methyl phenyl ) -carbamoyl oxy 3-pheny 1 | -thlocarbamate.

12. A herblcldal preparation which comprises a compound of the general formula I 38183/2 1n which j represents a lower alkyl group and 2 represents a phenyl or alkyl phenyl group* 1n admixture or conjunction with a suitable carrier.

13. A herblddal preparation which comprises a compound as claimed 1n claim 2 or 3, 1n admixture or conjunction with a suitable carrier.

14. A herblddal preparation which comprises the compound claimed 1n any one of claims 4 to 11 , In admixture or conjunction with a suitable carrier.

15. A method of protecting a living plant against weeds , wherein the area In the vicinity of a living plant Is treated with a compound of the general formula I , as defined In claim 1.

16. A method of protecting a living plant against weeds , wherein the area In the vicinity of a living plant 1s treated with a compound as claimed 1n claim 2 or 3. V.

17. A method of protecting a living plant against weeds, wherein the area In the vicinity of a living plant 1s treated with the compound claimed In any one of claims 4 to 11.

18. A method of protecting a crop area against weeds , wherein a crop area 1s treated with a compound of the general formula I , as defined 1n claim 1 .

19. A method of protecting a crop area against weeds , wherein a crop area 1s treated with a compound as claimed In claim 2 or 3.

20. A method of protecting a crop area against weeds , wherein a crop area s treated with the compound claimed In any one of claims 4 to 11.

21. A process for the manufacture of a compound of the general formula I 38183/2 In which represents a lower alk l group and Rg represents a phenyl or al yi phenyl group, wherein a compound of the general formula s Veated In the presence of an Inorganic or organic base with an amine of the formula ^ R, 1 NH 1n which R^ and Rg have the meanings given above, or a compound of the general formula or a salt thereof Is reacted 1n the presence of an Inorganic or organic base with a carbamoyl chloride of the general formula 1n which R^ and R2 have the meanings given above; or a compound of the general formula 38183/2 1n which and Rg have the meanings given above, 1s catalytlcally reduced to the corresponding amine which 1s then reacted with a compound of the formula CH3 - S - CO - CI .

22. A process as claimed 1n claim 21 , wherein the catalytic reduction Is carried out with the use of Raney nickel 1n methanol .

23. A process as claimed In claim 21 or 22, wherein the reaction with the compound of the formula Is carried out In the presence of an Inorganic or tertiary organic base.

24. A process as claimed In claim 21 , conducted substantially as described 1n Example 1 or 2 herein. For the Applicants Wolff, Bregman and Goller By: -¾ , J^