EP0000324B1

EP0000324B1 - Substituted cyclopropylmethoxy anilides, their preparation and their use as herbicides

Info

Publication number: EP0000324B1
Application number: EP78100019A
Authority: EP
Inventors: Anthony Felix Raymond
Original assignee: Stauffer Chemical Co
Current assignee: Stauffer Chemical Co
Priority date: 1977-06-21
Filing date: 1978-06-01
Publication date: 1980-10-01
Also published as: YU226382A; IT1105426B; DK266578A; RO83446A; ZA783180B; PH13812A; DE2860186D1; US4149874A; RO83446B; IL54783A; JPS5838422B2; HU184675B; PL207767A1; PL110841B1; YU143678A; BR7803787A; JPS584757A; BG30613A3; JPS6059901B2; AU3664078A

Description

This invention relates to substituted cyclpropylmethoxy anilides and their use as herbicides.
British Patent 1,093,121 discloses certain etherified p-hydroxyanilines, all of which require the presence of a tertiary aliphatic radical in the group. These compounds are analgesic and have no herbicidal activity disclosed. United States Patent 3,761,592 discloses compounds which are growth promoters for veterinary use and are based on a quinoline carboxylic acid structure. Such compounds are not relevant to those described in the present patent application which are not quinolines and which are herbicides, and have no disclosed veterinary properties.
The novel herbicidal compounds of this invention have the formula:
in which R, is straight or branched alkyl with 1-10 carbon atoms, lower alkenyl, chloro-lower alkyl, lower alkoxy, thio-lower alkyl, or
R₂ is hydrogen, lower alkoxyalkyl or lower alkanoyl; R₃ and R₄ are independently hydrogen, lower alkyl or lower alkoxy; X and Y are independently chloro, fluoro or bromo; Z is hydrogen, methyl, dimethyl, or one methyl and one chloro substituent; and n is 0 or 1, provided that if n is 1, R, is alkyl and R₂ is hydrogen, then R, is an alkyl group having from 1 to 4 carbon atoms.
By the term "alkyl" is meant such groups having from 1 to 10, preferably from 1 to 6 carbon atoms, including both straight chain and branched chain groups. Examples of alkyl groups are methyl, ethyl, n-propyl, isopropyl, butyl, 1-methylbutyl, and 1,1-dimethylbutyl groups.
By the terms "lower alkyl", "chloro-lower alkyl", "lower alkoxy", "thio-lower alkyl", "lower alkoxy- alkyl" and "lower alkanoyl" are meant such groups having from 1 to 4 carbon atoms. Examples of such groups are methyl, ethyl, isopropyl, n-butyl, methoxy, isopropoxy, α-chloroethyl, thioethyl, ethoxymethyl, propionyl, and the like.
By the term "lower alkenyl" is meant such groups having from 2 to 4 carbon atoms, for example, propenyl and isopropenyl.
By the term "lower cycloalkyl" is meant such groups having from 3 to 5 carbon atoms. A preferred member of this group is cyclopropyl.
In one embodiment of this invention, the compounds are ureas; that is R, is
In another embodiment, R, is alkyl, lower alkenyl, chloro-lower alkyl or lower cycloalkyl; the compounds are mono-amides; if R, is lower alkoxy the compounds are carbamates; if R, is thio-lower alkyl, they are thiocarbamates. If R, is as defined in the previous sentence, the nitrogen-containing group is referred to as the "amide moiety". If R₁ is an amide moiety and R₂is lower alkanoyl, the compounds are imides. R₂ is preferably hydrogen.
In one embodiment of the invention, the amide or urea moiety and the halo-substituted cyclopropylmethoxy moiety are substituted on the phenyl ring in the meta position with respect to each other. In another embodiment the two moieties are substituted on the phenyl ring in the para position with respect to each other. In a third embodiment the two moieties are substituted on the phenyl ring in the para position with respect to each other and a mono-chloro group is substituted on the phenyl ring in the ortho position with respect to the cyclopropylmethoxy substituent. This embodiment includes many of the most active compounds of this invention.
In another embodiment of the invention, X and Y are both chloro. In yet another embodiment of the invention, X is chloro and Y is bromo or fluoro. In still another embodiment of the invention, X and Y are both chloro and Z is 1-methyl. In another embodiment of the invention, Z is 3-chloro, 3-methyl.
The compounds of this invention have been found, in general, to be active herbicides; that is, they have been found to be herbicidally effective against various weeds. Weeds, in the broadest sense are plants which grow in locations in which they are not desired. The compounds of this invention have varied herbicidal activities; that is, the effect of the compounds on weeds differs according to the structure, with regard to pre- and post-emergence activity and grassy versus broadleafed plant response, as well as varied responses between species. In general, the compounds of this invention show at best only moderate general activity as pre-emergence herbicides but are primarily active as post-emergence herbicides at rates of application of up to about 8,98 kg/ha (8 pounds per acre) or higher. In general, as both pre-emergence and post-emergence herbicides, the compounds are active primarily against broad-leaf weeds; some of the compounds of this invention are active against both broadleaf and grass weeds as post-emergence herbicides.
These novel compounds may be employed as both general and selective herbicides. When employed at high rates they can be used as total weedkillers in places when complete or near complete destruction of vegetation is needed, for example, on railroad trackbeds, shoulders and median strips of highways, vacant lots, etc. When used at lower rates, the compounds may be satisfactory as selective herbicides; several of these compounds have been shown selective control of broadleaf weeds in small grain crops such as wheat and barley, even when applied at low rates.
It will be seen from the data given in Tables II and III that the compounds in which R, is lower alkoxy or thio-lower alkyl appear to be less active as a general matter than the corresponding alkyl compounds.
A herbicide as used herein, means a compound which controls or modifies the growth of plants. By the term "herbicidally effective amount" is meant an amount of the compound which causes a modifying effect upon the growth of plants. By "plants" is meant germinant seeds, emerging seedlings, and established vegetation, including roots and above-ground portions. Such modifying effects include all deviations from development, for example, killing, retardation, defoliation, desiccation, regulation, stunting, tillering, stimulation, leaf burn, dwarfing, and the like.
Therefore, in another aspect, this invention relates to herbicidal compositions of matter employing the compounds of the present invention in admixture with an inert diluent or carrier. In another aspect, this invention relates to a method for controlling undesirable vegetation comprising applying to the locus thereof a herbicidally effective amount of a compound of the present invention. In a preferred embodiment of this aspect, the compound is applied subsequent to the emergence of the undesired vegetation at the locus.
In general, the compounds of the present invention are prepared by:

(a) Reaction of a hydroxyaniline with a substituted cyclopropylmethylhalide:

The product of step (a) is then converted to the amide or urea in one or two steps. The amide can be produced in one step by simple acylation:
To form the ureas, the product of reaction (a) is preferably first reacted with phosgene instead of an acyl halide, to form an isocyanate, which is then reacted with an appropriate amine or alcohol to form the urea:
The imides (R_Z is lower alkanoyl) can be made from the amides by further acylation with an acyl chloride.
The compounds in which R₂is lower alkoxyalkyl can be made by reacting the amides with sodium hydride, followed by reaction with a halo alkyl ether, such as chloromethyl ethyl ether.
Reaction (a) can be enhanced by the use of a phase transfer catalyst such as a quaternary onium salt.
The following represent examples of preparation of compounds of the present invention.

Example 1

Preparation of N-3-(2',2'-dichloro-1'-methylcyclopropylmethoxyJphenyl cyclopropanecarboxylic acid amid (Compound 15 herein).

In a flask were placed 181 g. (2 moles) of methallyl chloride, 358 g. (3 moles) of chloroform and 3 g. (0.01 mole) of tetrabutyl phosphonium chloride. There was then added 9 moles of 50% sodium hydroxide solution, dropwise over two hours with vigorous stirring. After the addition was complete, the reaction mixture was stirred for four hours at 30°C. and then poured into two liters of water and extracted with methylene chloride. Distillation at 25 mm. gave 269 g. (77% yield) of 1,1-dichloro-2-chloromethyl-2-methylcyclopropane, b.p. 65-70°C.
51 g. (0.3 mole) of the compound prepared in the previous step was placed in a flask and mixed with 40 g. (0.37 mole) of 3-aminophenol, 60 g. (0.75 mole) of 50% sodium hydroxide solution, 30 ml. of water and 2 g. of tetrabutylphosphonium chloride. The reaction mixture was then heated to reflux with stirring for three hours, and then poured into 1 liter of water and extracted with methylene chloride. The extract was dried and methylene chloride stripped off at reduced pressure to yield 69 g. (93%) of 3-(2,2-dichloro-1-methylcyclopropyl)methoxyaniline, a dark amber oil.
In a third flask there were placed 2.5 g. (0.01 mole) of the compound prepared in the previous step, together with 1.05 g. (0.01 mole) of cyclopropanecarboxylic acid chloride, 1.01 g. (0.01 mole) of triethylamine and 25 ml. of ether. The flask was maintained at 5°C. during the filling with reactants. The reaction mixture was then stirred for two hours, poured into water and extracted with ether. The ether extract was washed successively with 1 M. hydrochloric acid and 1 M. sodium hydroxide, dried and stripped. There was obtained 2.5 g. (% of theoretical) of the desired compound, n³⁰ _D. The structure was confirmed by spectroscopic analyses.

Example 2

Preparation of 3-(2',2'-dichloro-1'-methyl cyclopropylmethoxyJ-2-methyl propionanilide (Compound 11 herein).

There were combined 2.5 g. (0.01 mole) 3-(2',2'-dichloro-1'-methyl-cyclopropylmethoxy)aniline, 1.07 g. (0.01 mole) isobutyryl chloride, 1.5 ml. (0.01 mole) triethylamine and 25 ml. ether. During the mixing, the temperature was maintained at 0°C. The mixture was stirred for 2 hours at room temperature; water was added and the mixture extracted with ether. The organic layer was dried and the ether removed under reduced pressure. There was obtained 2.8 g. of the desired compound, n³⁰ _D 1.5141.

Example 3

Preparation of N,N-dimethyl-N'(3-(2",2"-dichloro-1 "-methylcyclopropylmethoxyJphenylJurea (Compound 6 herein).

25 g. (0.1 mole) 3-(2',2'-dichloro-1'-methylcyclopropylmethoxy)aniline was dissolved in 150 ml. benzene. The solution was saturated with gaseous HCI and 100 ml. of a 12.5% solution of phosgene in benzene was added. The solution was refluxed for 3 hours, then cooled. The solvent was removed under reduced pressure. To the product of this reaction, 3-(2',2'-dichloro-I'-methylcyclopropyl- methoxy)phenyl isocyanate, 200 mi. methylene chloride was added and gaseous dimethylamine was bubbled in for 1/2 hour. The solution was stirred for 1/2 hour at room temperature, then the solvent was removed under reduced pressure. The residue was slurried in a 25% solution of ether in hexane. There was obtained 22 g. of the desired product, a white solid, m.p. 99-101 °C.

Example 4.

Preparation of N-(3-(2;2'-dichloro-1'-methylcyclopropylmethoxy)phenyl)0-isopropyl carbamate (Compound 9 herein).

4.1 g. (0.015 mole) 3-(2',2'-dichloro-1'-methylcyclopropylmethoxy)phenyl isocyanate was dissolved in 20 ml. methylene chloride. Then, 2 g. isopropanol was added and the solution stirred for 4 hours. The solvents were removed under reduced pressure to yield 5 g. of the desired compound as an oil, n³⁰ _D 1.5072.

Example 5

Preparation of O-ethyl N-3-(2',2'-dichloro-1'-methylcyclopropylmethoxylphenyl carbamate (Compound 21 herein).

A solution was formed by dissolving 6.5 g. (0.03 mole) 3-(2',2'-dichloro-1'-methylcyclopropyl- methoxy)aniline, 3.2 g. (0.03 mole) ethyl chloroformate and 3.1 g. (0.031 mole) triethylamine in 50 ml. benzene. The solution was refluxed for 3 hours and cooled. Methylene chloride was added and the organic layer was washed with water, dried and evaporated. There was obtained 8.7 g. of the desired product, n³⁰ _D 1.5113.

Example 6

Preparation of 3-(2"-chloro-2"-fluoro-1"-methylcyclopropylmethoxy)2',2'-dimethyl valeranilide (Compound 24 herein).

There were combined 5.0 g. (0.0226 mole) N-3-hydroxyphenyl-2,2-dimethylvaleramide, 3.15 g. (0.02 mole) 1-chloro-1-fluoro-2-chloromethyl-2-methyl cyclopropane, 2.0 g. (0.025 mole) of a 50% caustic solution, 2 ml. water and 300 mg. tetrabutyl phosphonium chloride. The mixture was refluxed for 2 hours; water was then added and the mixture extracted with methylene chloride. The organic layer dried and evaporated to yield 4.2 g. of the desired product, n³⁰ _D 1.4679.
The following Table I lists representative compounds of the present invention:

Herbicidal Screening Tests

The representative compounds in the foregoing Table I were tested as herbicides in the following manner:

A. Pre-emergence Herbicide Screening Test:

Using an analytical balance, 20 mg. of the compound to be tested was weighed out on a piece of glassine weighing paper. The paper and compound were placed in a 30 ml. wide-mouth bottle and 3 ml. of acetone containing 1% polyoxyethylene sorbitan monolaurate emulsifier was added to dissolve the compound. If the material was not soluble in acetone, another solvent such as water, alcohol or dimethylformamide (DMF) was used instead. When DMF was used, only 0.5 ml. or less was used to dissolve the compound and then another solvent was used to make the volume up to 3 ml. The 3 ml. solution was sprayed uniformly on the soil contained in a polystyrene flat, 17.78 cm (7") long, 12.7 cm (5") wide and 6.98 cm (2.75") deep one day after planting weed seeds in the flat of soil. An atomizer was used to apply the spray using compressed air at a pressure of 0.35 kg/cm² (5 Ib./sq. in.). The rate of application was 8.98 kg-ha (8 Ib./acre) and the spray volume was 541 1/0.404 ha (143 galjacre).
On the day preceding treatment, the flat was filled to a depth of 5.08 cm (2") with loamy sand oil. Seeds of seven different weed species were planted in individual rows one species per row across the width of the flat. The seeds were covered with soil so that they were planted at a depth of 1.27 cm (0.5"). The seeds used were those of four grasses: hairy crabgrass (Digitaria sanguinalis), yellow foxtail (Setaria glauca), watergrass (Echinochloa crusgalhl, red oat (Avena sativa), and three broadleaf weeds: redroot pigweed (Amranthus retroflexus), Indian mustard (Brassica juncea) and curly dock (Rumex crispus). Ample seeds were planted to give about 20 to 50 seedlings per row after emergence depending on the size of the plants.
After treatment, the flats were placed in the green-house at a temperature of 21.1-29.4°C (70 to 85°F.) and watered by sprinkling. Two weeks after treatment the degree of injury or control was determined by comparison with untreated check plants of the same age. The injury rating from 0 to 100% was recorded for each species as percent control with 0% representing no injury and 100% representing complete kill. Results of these tests are shown in the following Table II.

B. Post-emergence Herbicide Screening Test:

Seeds of six plant species, including three grasses: hairy crabgrass, watergrass, red oat and three broadleaf weeds: mustard, curly dock and pinto beans (Phaseolus vulgaris) were planted in the flats as described above for pre-emergence screening. The flats were placed in the green house at 21.1-29.4°C (70 bis 85°F.) and watered daily with a sprinkler. About 10 to 14 days after planting when the primary leaves of the bean plants were almost fully expanded and the first trifoliate leaves were just starting to form, the plants were sprayed. The spray was prepared by weighing out 20 mg. of the test compound, dissolving it in 5 ml. of acetone containing 1% polyoxyethylene sorbitan monolaurate and then adding 5 ml. of water. The solution was sprayed on the foliage using an atomizer at an air pressure of 5.62 kg/ha. (5 Ib./sq. in.). The spray concentration was 0.2% and the rate was 8.98 kg/ha. (8 Ib./acre). The spray volume was 1804 I/0.404 ha. (476 gal./acrel. Results of these tests are shown in Table III.
The compounds of the present invention are used primarily as post-emergence herbicides and ₃₅ may be applied in a variety of ways at various concentrations.
In practice, the compounds are formulated with an inert carrier, utilizing methods well known to those skilled in the art, thereby making them suitable for application as dusts, sprays, or drenches and the like, in the form and manner required. The mixtures can be dispersed in water with the aid of a wetting agent or they can be employed in organic liquid compositions, oil and water, water in oil emulsions, etc., with or without the addition of wetting, dispersing or emulsifying agents. An herbicidally effective amount depends upon the nature of the seeds or plants to be controlled and the rate of application may vary from 0.056-56.2 kg/ha. (0.05 to approximately 50 pounds per acre).
The phytotoxic compositions of this invention employing an herbicidally effective amount of the compounds described herein are applied to the plants in the conventional manner. Thus, the dust and liquid compositions can be applied to the plant by the use of power-dusters, boom and hand sprayers and spray-dusters. 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 growth of germinating seeds or emerging seedlings, as a typical example, the dust and liquid compositions are applied to the soil according to conventional methods and are distributed in the soil to a depth of 1.27 cm (1/2 inch) below the soil surface. It is not necessary that the phytotoxic compositions be admixed with the soil particles, since these compositions can 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 filled to be treated. This method of application permits the penetration of the compositions into the soil as the water is absorbed therein. Dust compositions, granular compositions or liquid formulations applied to the surface of the soil can be distributed below the surface of the soil by conventional means such as discing, dragging or mixing operations.

Claims

1. A compound having the formula

in which R, is straight or branched alkyl with 1-10 carbon atoms, lower alkenyl, chloro-lower alkyl, lower cycloalkyl, lower alkoxy, thio-lower alkyl, or

R₂ is hydrogen, lower alkoxy-alkyl or lower alkanoyl; R₃ and R₄ are independently hydrogen, lower alkyl or lower alkoxy; X and Y are independently chloro, fluoro or bromo; Z is hydrogen, methyl, dimethyl or one methyl and one chloro substituent; and n is 0 or 1, provided that if n is 1 and R, is alkyl, then R, is an alkyl group having from 1 to 4 carbon atoms.

2. A compound according to Claim 1 in which R₁ is

3. A compound according to Claim 1 in which R₁ is straight or branched alkyl with 1-10 carbon atoms, lower alkenyl, chloro-lower alkyl, lower cycloalkyl, lower alkoxy, or thio-lower alkyl.

4. A compound according to Claim 1 in which R, is cyclopropyl, R₂ is hydrogen, X and Y are each chloro, Z is 1-methyl, n is 1 and the cyclopropylmethoxy and amide moieties are substituted on the phenyl ring in the para position with respect to each other.

5. A compound according to Claim 1 in which R₁ is isopropenyl, R₂ is hydrogen, X and Y are each chloro, Z is 1-methyl, n is 1 and the cyclopropylmethoxy and amide moieties are substituted in the para position with respect to each other.

6. A compound according to Claim 1 in which R₁ is N(CH₃)₂, R₂ is hydrogen, X and Y are each chloro, Z is 1-methyl, n is 0 and the cyclopropylmethoxy and urea moieties are substituted on the phenyl ring in the meta position with respect to each other.

7. A compound according to Claim 1 in which R₁ is 1,1 -dimethyibutyi, R₂ is hydrogen, X and Y are each cloro, Z is hydrogen, n is 0 and the cyclopropylmethoxy and amide moieties are substituted on the phenyl ring in the meta position with respect to each other.

8. A herbicidal composition of matter comprising a herbicidally effective amount of a compound as defined in any of claims 1-7 and an inert carrier or diluent.

9. A method for controlling undesirable vegetation comprising applying to said vegetation or the locus thereof a herbicidally effective amount of a compound or composition as defined in any of Claims 1-8.

10. A method according to Claim 9 in which the compound or composition is applied subsequent to the emergence of the undesirable vegetation.

11. A method according to Claim 9 in which the compound or composition is applied at a rate of 0.056-56.2 kg/ha (0.05 to 50 pounds per acre).

12. A method for production of a compound as defined in any of Claims 1-7 comprising

a) reacting a hydroxyaniline having the formula

with a substituted cyclopropylmethyl halide having the formula

in the presence of a base; and either:

b) reacting the product of step (a) with an acyl halide having the formula

to form an amide; or

c) reacting the product of step (a) with phosgene, and

d) reacting the product of step (c) with a compound having the formula NHR₃R₄ to produce a urea.