CA1071234A - N-(1,1-SUBSTITUTED PROPYNYL)-.alpha.-(3,5-SUBSTITUTED PHENOXY) ALKYL AMIDES AND THEIR USE AS HERBICIDES - Google Patents

Abstract

Abstract of the Disclosure N-(l,l substituted propynyl)- q (3,5-substitted phenoxy) alkyl amides compounds having the formula

Description

. 071Z34 This invention relates to certain novel N-(l,l substituted propynyl)-~-(3,5-substituted phenoxy) alkyl amides which are useful as herbicides.

The compounds of the present invention are new compositions of mat~er and correspond to the formula ~ O-C-C-N- ~ ~ECH

in which Rl and R2 are independently halcgen, ~reerably chlorine or alkyl having 1 to 4 carbon atoms, preferably methyl; R3 is alkyl having 1 to 4 carbon atom~, preferably ethyl; R4 and R5 are independently hydrogen or alkyl having 1 to 3 carbon atoms, preferably methyl, more preferably both R4 and R5 are methyl.

In the above description of the compounds of this invention, alkyl includes both straight chain and branchet chain configurations, for example, methyl, ethyl, n-propyl, i~opro w l, n-butyl, sec-butyl or tert.-butyl. The term halogen includes chlorine, bromine, iodine and fluorine.

The closest prior art known to applicants is U. S.
3,272,844.

The compounds of thi~ invention are sctive herbicides of a general type. That is, they are herb~cidally effective sgainst a w1te range of plant species. The method of control-ling undesired vegetation of the present invention comprises applying an herbicidally effective amount of the above-tescribed compounds to the area where control is desired ~(~71Z34 An herbicide is used herein to mean a compound which controls or modifies the grow~h of plants. By a "growth con-trolling amount" is meant an amount of compound which causes a difying effect upon the growth of plants. Such m~difying effects include all deviations from natural development, for example, killing, retardation, defoliation, dessiccation, regulation, stunting, tillering, st~mulation, dwarfing and the l~ke. By "plants" it is meant germinating seeds, emerging seedlings, and established vegeta~ion including the roots and above-ground portions.

The compounds of the present invent~on are prepared by the following general method.

Reaction No. 1 ~2 OH ~ Br~-8-OH ~ NaOH--~
Rl ~ H ~
R2 ~ 0-~3C-OH ~ NaBr Generally, a le amount of the phenol, a slight mole excess of the ~-bromoaIkanoic acid and about 3 moles of sodium hydroxide are mixed in water at about 10C-15C. Then the re-action m~xture is heated at reflux for about 2 hours. Thereafter the mixture is cooled and tiluted with water. The pH of the mixture is ad~usted to 8 with 19% hydrochloric acit. The solution i8 extracted several times with ether followed by a pH ad~ustment to 2 with 19% HCl. An oil separates which is extracted with ether.

~0'7~Z34 Evaporation of the ether after drying yields the desired product which is asolid. The solid is purified by recrystalization with cyclohexane.

Reaction No. 2 R2 O-¢-C-OH + Cl-C-Cl ~ ~ ¢ 8 First the acid is mixed in benzene. A small amount o the dimethyl formamide i8 added and the slurry is heated. A
slight excess of the phosgene reactant is added to the acid mixture in portions, The reaction is complete upon termina-tion of HCl evolution. Evaporation of the reaction mixture yields the desired product, a liquid.

Reaction No. 3 Rl O-~-C-Cl + H2N-C-C-CE + (C2H5)3N--~

Rl ~ O ~ ~4 R ~ R3 R5 About equal mole amounts of the amines are dissolved in benzene. The solution is cooled to about 10C. About an equal mole amount of the acid chloride reactant is slowly added to the amine solution at a rate to maintain the temperature between 10-15C. After the acid chloride addition is complete, the mixture - is heated to 45-50C. for 1 hour and then is cooled to room temperature. The mixture is diluted with H20 to dissolve the amine hydrochloride. Some solid remains undissolved and this is filtered. The filtrate is washed two times with 10% HCl. With each wash more solid separate~ and it is filtered. The organic layer i8 next washed two t~mes with 5% ~a2C03 and dried over Mg S04 Removal of solvent leaves a solid product which is com-bined with the solid product previously removed.

Preparation of the compounds of this invention is illustrated by the following reaction.

Example Preparation of N-(l,l dimethyl propargyl)-~ -(3,5-dichlorophenoxy) butvramide Cl ~ ~ U CIH3 ~ OCH C - N - IC - C'CH
Cl CH2CH3 CH3 100.0 g. (0.614 moles) of 3,5-dichlorophenol and 112.5 g. (0.675 moles) of ~-Bromobutyric acid are mixed and 100 ml. of water is added. The mixture i8 cooled to 10C. in an ice wster bath and 147.2 g. (1.842 moles) 50Z NaOH i8 added dropwise over lO-15C. The reaction mixture is wanmed to room temperature and then heated at reflux for two hours.
A~ter cooling, the mixture i8 diluted with H20 to 600 ml.ant the pH is ad~usted to 8 with 19% HCl. The aqueous solution is extracted 3 times with 150 ml.portions of ether and is then ad~usted to pH 2 with 19% HCl. An oil separates which is 1C~7~234 extracted with ether. Evaporation of the ether after drying leaves a white solid, 94.3 g., m.p. 102-108C. This solid is recrystalized from 250 ml. cyclohexane to give 71.8 g. ~ -(3,5-dichlorophenoxy) butyric acid m.p. 113-116C.

71.8 g. (0.288 moles) of ~-(3,5-dichlorophenoxy) butyric acid and 75 ml. of benzene are placed in a 500 ml. flask to which a dropping funnel with dry-ice condenser is attached.
The slurry is stirred and the 0.2 ml. dimethyl formamide is added. The mixture is heated to 35C. and 10 g. of phosgene is condensed into the mixture to initiate reaction. The start of the reaction is evidenced by HCl evolut~on and foaming.
26.0 g. more phosgene is added in 5 gm. increments. At the conclusion of the reaction (HCl evolution ceasing), the reaction mixture is evaporated leaving a re9idu`al1iquid C~-(3~5-dichlorophenoxy) butyryl chloride 77.6 g., N20 - 1.5345 164 g. (1 63 les) triethyl amine and 132 g. (1.58 mole8) 3-methyl-3-amino-1-butyne àre dissolved in 1300 ml.
benzene and the solution is cooled to 10C. in an ice water bath.

412.9 g. (1.55 les)c~-(3,5-dichlorophenoxy) butyryl chloride diluted with 200 ml. benzene is added dropwise to the amine 801ution. Periodic additions of benzene (400 ml.) are made in order to adequately stir the mixture. After acid chloride addition is complete, the mixture is heated to 45-50C.
for 1 hour more and then allowed to come to room temperature overnight. The mixture is diluted with lO00 ml. H20 to dissolve ~07~234 the amine hydrochlor~de. Some solid remains undissolved and th~s i8 filtered. The filtrate is washed two t~mes with 1000 ml.
10% HCl. With each wash more solid separates and it is filtered. The organic layer is next washed two times with 5%
Na2C03 and dried over Mg S04. Removal of solvent leaves 377 g.
which is combined with the previously removed solid to yield 436 g, of the desired product, m.p. 90-94C.

The foll~wing is a table of certain selected compounds that are preparable according to the procedure described hereto. Compound numbers are assigned to each compound and are used through the remainder of the application.

Table I

~2 ~ O-~-C-N-~ C--CH

Compound 4 5 Number Rl R2 R3 R R

2 a) Cl Cl CH3CH2 CH3 CH3

3 CH3 CH3 ' CH3CH2 CH3 CH3

4 Cl Cl CH(CH3) 2 CH3 CH3 Cl Cl CH3CH2cH2 CH3 CH3 6 Cl Cl CH3CH2 H H

a) Prepared in Example 1.

Herbicidal Screenin~ Tests As previously mentioned, the herein described compounds produ~ed in the above-described manner are phyto-toxic compounds which are ~eful and valuable in controlling various plant species. Selected compoundsof this in~ention are tested as herbicites in the follow~ng manner.

Pre-emergence herbicide test. On ~he day pre-ceding treabment, seeds of seven different weed specie~ are planted in individual rows using one species per row across the width of the flat. The seeds used are hairy crabgrass (Digitaris san~u~nalis (L.) Scop.), yellow foxtail (Setaria ~lauca (L ) Beauv.), watergrass (Echinochloa crusgalli (L.) Bea w .), California red oat (Avena sativa (L.), redroot pigweed (Amaranthus retroflexu~ (L ) Indian mustard (Brassica 1uncea (L.) Coss.) and curly dock (Rumex crispus (L.). Ample seeds are planted to give about 20 to 50 seedlings per row, after emergence, depending upon the size of the plants.
The flats are watered after planting. The spraying solution is prepared by dissolving 50 mg. of the test compound in 3 ml.
of a solvent, ~uch as acetone, containing 1% Tween 2 ~
(polyoxyethylene sorbitan monolaurate). The following day esch flat is sprayed at the rate of 20 pounds of the candidate campound per 80 gallons of solution per acre. An atomizer is used to spray the solution onto the soil surface. The flats are placed ln a greenhouse at 80F. and watered regularly.
Two weeks later the degree of weed control i9 tetermined by comparing the amount of germination and growth of each ~07~Z34 weed in the treated flats with the same weeds in several un-treated control flats. The rating system is as follows:

- - no significant injury (0-15 percent control) + ~ slight injury (25-35 percent control) ++ ~ moderate injury (55-65 percent control) lll = severe injury or death (85-100 percent control) An activity index i~ used to represent the total activity of all seven weed species. It is the sum of the number of plus marks, so that an activity index of 21 represents a~most complete control of all seven weeds. The result~ of this test are reported in Table II.

Post-emergence herbicide test. Seeds of five weed species including hairy crabgrass, watergrass, California red oats, Indian mu~tard, and curly dock and one crop, pinto beans (Phaseolus vulgaris), are planted in flats as described above for pre-emergence screening. The flats are placed in the greenhouse at 72-85F. and watered daily with a sprinkler About 10 to 14 day~ after planting when the pr~mary leaves of the bean plant are a~most fully expanded and the first trlfoliate leaves are ~ust starting to form, the plants are sprayed. The spray ls prepared by weighing out 50 mg. of the test compound, dissolving it in 5 ml. of acetone con-taining 1% Tween 2 ~ (polyoxyethylene sorbitan monolaurate) and then addlng 5 ml. of water. The solution is sprayed on the foliage using an atomizer. The spray concentrat~on is 0.5% and the rate would be approx~mately 20 pounds per acre if all of the spray was retained on the plant and the soil, 107~Z34 but some spray is lost so it is est~mated that the applica-tion rate is approx~mately 12.5 pounds per acre.

Beans are used to detect defoliants and plant growth regulators. The beans are tr~mmed to two or th~ee plants per flat by cutting off the excess weaker plants several days before treatment. The treated plant~ are placed back in the greenhouse and care is taken to avoid sprinkling the treated foliage with water for three days after treatment.
Water is applied to the soil by means of a slow stream from a watering hose taking care not to wet the foliage.

In~ury rates are recorded 14 tays after treatment.
The rating 9ystem is the same as described above for the pre-emergence test where (-), (~ +), and (lll) are used for the different rates of injury and control. The injury symptoms are also recorded. The maximum activity index for complete control of all the species in the post-emergence screening test is 18 which represents the sum of the plus marks obtained wlth the 9iX plant 9pecies used ln the test. The herbicide activity is shown in Table II.

~071Z34 - TABLE II

HERBICIDAL ACTIVITY
SCREENING RESULTS
Herbicidal ActivitY Index**

Compound Pre-~mer~ence Post-emergence Number (20 lb7A) (12.5 lb/A) 1 21 i7 ** 21 - 85-100% control of all seven plant species tested pre-emergence.
18 - 85-100% control of all six plant species tested post-emergence.
The compounds of the present invention are used as pre-emergence or post-emergence herbicides and are applied in a variety of ways at various concentrations. In practice, the compounds herein defined are formulated into herbicital composition~, by admixture, in herbicidally effective amounts, with the ad~uvants and carriers normally employed for facili-tating the disper~ion of act~ve ingredients for agricultural applications, recognizing the fact that the formulation and mode of application of a toxicant may affect the activity of the materials in a given application. Thus, these active herbicidal compounds may be formulated as granules of relatively large particle size, as wettable powders, as emulsifiable concen-trates, as powdery dusts, as ~olutions or as any of several other known types of fonmulations, depend~ng upon the desired 107~Z34 mode of application. Preferred fonmulations for both pre- and post- emergence herbicidal applications are wettable powders, emulsifiable concentrates and granules. These formulations may contain as lit~le as about 0~5% to as much as about 95%
or more by weight of active ingredient. The amount applied depends upon the nature of the seeds or plants to be controlled andthe rate of application varies from ~8 to approximately 50 pound~ per acre.

Wettable powders are in the fonm of finely divided particles which di~perse readily in water or other dispersant.
The wettable powder i~ ultimately applied to the soil either as a dry dust or as a dispersion in water or other liquid.
Typical carriers for wettable powders include fuller's earth, kaolin clays, silicas and other readily wet organic or inorganic diluents. Wettable powders normally are prepared to contain about 5% to about 95% ofthe active ingredient by weight and usually also contain a small amount of wetting, dispersing or emulsifying agent to facilitate wetting and dispersion.

Emulsifiable concentrates are homogeneou~ liquid compositions which are dispersible in water or other dispersant, and may consist entirely of the active compound with a liquid or solid emulsifying agent, or may also contain a liquid carrier, quch as xylene, heavy aromatic naphthas, isophorone and other non-volatile organic solvents. For herbicidal appli-cstion, these concentrates are dispersed in water or other liquid carrier and normally applied as a spray to the area to be treated. The percentage by weight of the essential active ingredient may vary according to the manner in which the composition is to be applied, but in general comprises about 0.5% to 95% of active ingredient by weight of the herbicidal composition.

Granular formulations, wherein the toxicant is carried on relatively coarse particles, are usually applied without dilution to the area in which suppression of vegetation is desired. Typical carriers for granular formulations include sant, fuller's earth, bentonite clays, vermiculite, perlite and other organic or inorganic materials which absorb or which may be coated with the toxicant. Granular formulations normally are prepared to contain about 5% to about 25% of active ingredient and may also contain small amounts of other ingredients which may include surface-active agents such as wetting agents, dispersing agents or emulsifiers; oils such as heavy aromatic naphthas, kerosene or other petroleum fractions, or vegetable oils; ant/or stickers such as dextrin~, glue or synthetic resins.

Typical wetting, disper9ing or emulsifying agents used in agricultural formulations include, for example, the alkyl and alkylaryl sulfonates and sulfates and their sodium salts; polyhydric alcohols; and other types of surface-active agents, many of which are av~able in commerce. The surface-active agent, when used, normally comprises from 0.1% to 15%
by weight of the herbicidal composition.

Dusts, which are free-flowing admixtures of the active ingredient with finely divided solids such as talc, clays, flours, and other organic and inorganic solids which act as dispersants and carriers for the toxicant, are useful formulations for soil-incorporating applications.

~07~Z34 Pastes, which re homogeneous suspensions of a finely divided solid toxicant in ~ liquid carrier such as water or oil, are employed for specific purposes. These for-mulations norm2lly contain about 5% to about 95% of active ingredient by weight, and may also contain small amounts of a wetting, dispersing or emulsifying agent to facilitate dis- ~ -persion, For application, the pastes are normally diluted and applied as a spray to the area to be affected.

Other useful fonmulations for herbicidal applica-tions include s~mple solutions of the active ingredient in a dispersant in which it is completely soluble at the desired concentrat~on, such as acetone, alkylated naphthalenes, xylene or other organic solvents. Pressurized sprays, typically aerosols, wherein the active ingredient is dispersed in finely-divided form as a result of vaporization of a l~w boiling di~persant solvent carrier, such as the Freons, may also be used.

The phytotoxic compositions of this invention are applied to the plants in the conventional manner. Thus, the du~t and liquid compositions can be applied to the plant by the use of power-dusters, boom and hand sprayers and spray du ters. The compositions can also be applied from airplanes as a dust or a spray because they are effective in very low dosages, In order to modify or control grGwth of germinat~ng ~eeds or emerging seedling~, as a typical example, the dust and liquid compositions are applied to the soil according to con-vention methods and are distributed in the soil to a depth of at least 1¦2 inch below the soil surface, $t is not necessary _, ~

107~234 that the phytotoxic compositions to be admixed with the soil particles since these compositions can also be applied merely by spraying or sprinkling the surface of the soil.
The phytotoxic compositions of this invention can also be applied by addition to irrigation water supplied to the field to be treated. This method of application penmits the penetration of the compositions into the soil as the water i~ absorbed therein. Dust compositions, granular compositions or liquid formulations applied to the surface of the soil can be distributed below the surface of the 80il by con~entional means such as discing, tragging or mixing operations.
The phytotoxic compositions of this invention can also contain other additaments, for example, fertilizers, pesticides and the like,used as ad~uvant or ~n combination with any of the above-described adjuvants. Other phytotoxic compounds useful in combination with the above-described compounds include, for example, 2,4-dichlorophenoxyacetic acids, 2,4,5-trichlorophenoxyacetic acid, 2-methyl-4-chlorophenoxy-acetic acid and the salts, esters and amides thereof; triazine derivatives, such as 2,4-bis(3-methoxypropylamino)-6-methylthio-s-triazine, 2-chloro-4-ethylEmino-6-isopropylamino-s-triazine, and 2-ethylsmino-4-isopropylamino-6-methylmercapto-s-triazine;
urea derivatives, such as 3-(3,4-dichlorophenyl)-1,1-dimethyl urea and 3-(p-chlorophenyl)-1,1-dimethyl urea: and acetsmides such as N,N-diallyl-O~-chloroacetamide, and the like;
benzGic acids such as 3-amino-2,5-dichlorobenzoic; thio-carbamates, such as S-propyl d~propylthiocarbamate, S-ethyl-dipropylthiocarbamate, S-ethyl cyclohexylethyl thiocarbamate, S-ethyl hexahydro-lH-azepine-l-car~othioate and the like;
4-(methylsulfonyl)-2,6-dinitro-~,N-substituted anilines, such as 4-(methylsulfonyl)-2,6-dinitro-N,N-di-n-propyl aniline, 4-trifluoromethyl-2,6-dinitro-N,~-substituted anilines, such as 4-trifluoromethyl-2,6-dinitro-N,N-di-n-propyl anilihe and 4-trifluoromethyl-2,6-dinitro-N-ethyl-N-n-butyl aniline.
Fertilizers useful in combination with the active ingredients include, for example, ammonium nitrate, urea and superphosphate Other useful additaments include materials in which plant organisms take root and grow such as compost, manure, humus, sand and the like.

The concentration of a compound of the present invention, constituting an effective amount of the best mode of atministration in the utility disclosed is readily deter-minable by those skilled in the art.

Claims (18)

IT IS CLAIMED:

1. Compounds of the formula in which Rl and R2 are independently halogen or alkyl having 1 to 4 carbon atoms; R3 is alkyl having 1 to 4 carbon atoms, R4 is hydrogen or alkyl having 1 to 3 carbon atom and R5 is hydrogen or alkyl having 1 to 3 carbon atoms.

2. The compound of Claim 1 in which R1 is methyl, R2 is methyl, R3 is ethyl, R4 is alkyl having 1 to 3 carbon atoms and R5 is alkyl having 1 to 3 carbon atoms.

3. The compound of Claim 1 in which R1 is chloro, R2 is chloro, R3 is ethyl, R4 is alkyl having 1 to 3 carbon atoms and R5 is alkyl having 1 to 3 carbon atoms.

4. The compoùnd of Claim 1 in which R1 is methyl, R2 is methyl, R3 is ethyl, R4 is hydrogen and R5 is alkyl having 1 to 3 carbon atoms.

5. The compound of Claim 1 in which R1 is chloro, R2 is chloro, R3 is ethyl, R4 is hydrogen, and R5 is alkyl having 1 to 3 carbon atoms.

6. The compound of Claim 1 in which R1 is methyl, R2 is methyl, R3 is ethyl, R4 is hydrogen, and R5 is hydrogen.

7. The compound of Claim 3 in which R1 is chlorine, R2 is chlorine, R3 is ethyl, R4 is methyl, and R5 is methyl.

8. The compound of Claim 2 in which R1 is methyl, R2 is methyl, R3 is ethyl, R4 is methyl and R5 is methyl.

9. The compound of Claim 1 in which R1 is chlorine, R2 is chlorine, R3 is ethyl, R4 is hydrogen and R5 is hydrogen.

10. The method of controlling undesirable vegetation which comprises applying to the area where control of said vegetative growth is desired, a growth controlling amount of a compound having the formula in which R1 ant R2 are independently halogen or alkyl having 1 to 4 carbon atoms; R3 is alkyl having 1 to 4 carbon atoms, R4 is hydrogen or alkyl having 1 to 3 carbon atoms and R5 is hydrogen or alkyl having 1 to 3 carbon atoms.

11. The method of Claim 10 in which R1 is methyl, R2 is methyl, R3 is ethyl, R4 is alkyl having 1 to 3 carbon atoms and R5 is alkyl having 1 to 3 carbon atoms.

12. The method of Claim 10 in which R1 is chloro, R2 is chloro, R3 is ethyl, R4 is alkyl having 1 to 3 carbon atoms and R5 is alkyl having 1 to 3 carbon atoms.

13. The method of Claim 10 in which R1 is methyl, R2 is methyl, R3 is ethyl, R4 is hydrogen and R5 is alkyl having 1 to 3 carbon atoms.

14. The method of Claim 10 in which R1 is chloro, R2 is chloro, R3 is ethyl, R4 is hydrogen, and R5 is alkyl having 1 to 3 carbon atoms.

` 15. The method of Claim 10 in which R1 is methyl, R2 is methyl, R3 is ethyl, R4 is hydrogen, and R5 is hydrogen.

16. The method of Claim 12 in which R1 is chlorine, R2 is chlorine, R3 is ethyl, R4 is methyl, and R5 is methyl.

17. The method of Claim 11 in which R1 is methyl, R2 is methyl, R3 is ethyl, R4 is methyl and R5 is methyl.

18. The method of Claim 10 in which R1 is chlorine, R2 is chlorine, R3 is ethyl, R4 is hydrogen, and R5 is hydrogen.