KR820000779B1 - Process for the preparing herbicidally active phenyulurea derivatives - Google Patents

Abstract

Title compds. (I; R1 = H, C1-4 alkyl, C2-4 alkenyl, C2-4 alkinyl, methoxy; R2 = H, C1-4 alkyl; R3 = H, C1-4 alkyl; R4 = halogen; R5 = halogen; X = H, C1-4 alkyl, halogen, methoxy; n = 1-2), useful as herbicides, were prepd. by the reaction of compd. II and III. Thus, 22 g 1-bromomethyl-2,2-dichlorocyclopropane, 16 g CaCO3 and 2 g sodium iodide were reacted with 17 g 1,1-dimethyl-3-(3-hydroxyphenyl)-urea in 60 ml DMF. after 20 hr, 6 g 1-bromoethyl-2,2-dichlorocyclopropane and 5 g K2CO3 were added, and stirred for 6 hr to give 19.9 g 1-[3-(2,2-dichlorocyclopropylmethoxy)-phenyl -1,3-dimethylurea.

Description

Method for preparing herbicide phenylurea derivative

The present invention relates to a process for the preparation of the novel phenylurea derivatives of the following general formula (I) which are useful as herbicides.

In the above general formula

R ₁ is hydrogen, alkyl of 1 to 4 carbon atoms, alkenyl of 2 to 4 carbon atoms, alkynyl or methoxy group of 2 to 4 carbon atoms

R ₂ is hydrogen or an alkyl group having 1 to 4 carbon atoms

R ₃ is hydrogen or an alkyl group of 1 to 4 carbon atoms

R ₄ is halogen

R ₅ is halogen

x is hydrogen, alkyl group of 1 to 4 carbon atoms, halogen or methoxy group, respectively

n is 1 or 2.

The compounds of the present invention excel in soil weeding and lobe weeding and have broad selectivity for cultivation. Therefore, this compound is particularly advantageous for use in removing monocotyledonous and dicotyledonous weeds in cultivated crops.

When the compounds were used for pre-germination and post-germination treatment, they were found in the genus Sinapis sp, Stellari media, Senezio vulgaris, Matricaria chamomilla, Chrysantemum. Chrysanthemum segetum, Ipomoea purpurea, Lamium amplexicaule, Centaurea cyanus, Amaranthus retroflexus, Alopea Eliminate agricultural weeds such as Alopecurus myosuroides and Lolium perenne.

The amount necessary to remove weed seeds is generally used in the range of 1 kg to 5 kg of active ingredient per hectare. By doing so it can be seen that the active compounds of the present invention are selective for useful plant crops such as French beans, peanuts, potatoes, rice, sorghum, maize, kernel grains and soybean crops. When two or more compounds of Formula (I) are used, the total amount is 1 to 5 kg.

When used in large amounts, this compound is also effective for inhibiting or eliminating the growth of waste plants.

The present invention also provides a herbicide comprising a compound of formula (I) and a suitable carrier.

The present invention provides a method of protecting the growth plants from weeds by spraying the compound of the general formula (I) and the growing plant in the vicinity of the weed and a method of protecting the crop area from the weeds by spraying the compound of the general formula (I) to the crop area. to provide.

The present invention provides a method for protecting waste paper waste from weeds by spraying one or more compounds of formula (I) to the waste paper waste in a total amount of 5 kg or more per hectare.

The present invention also provides a pack with instructions explaining the use of the compound of formula (I) as a herbicide.

The compounds of the present invention may be used alone or in admixture with other active substances. If necessary, other deciduous agents, plant protection agents and / or pesticides may be added depending on the desired purpose.

Other herbicides can be added if the broader action is intended. Suitable herbicidal (co) crude ingredients include triazines, aminotriazoles, anilides, diazines, uracils, aliphatic carboxylic acids and halocarboxylic acids, substituted benzonic and aryloxycarboxylic acids, hydrazides, amides, nitriles, esters of carboxylic acids, Chest acid esters and thiocarbamic acid esters, urea, 2,3,6-trichlorobenzyloxypropanyl, and thiocyanate-containing agents.

Among the other additives are non-toxic additives which increase the action of herbicides to give synergism, in particular such as wetting agents, emulsifiers, solvents and oily additives.

The active compounds of the present invention or mixtures thereof and / or the addition of solid excipients or diluents, if necessary, of herbicides such as powdered powders, dispersant granules, solvents, emulsions, suspending agents to which surfactants such as wetting agents, adsorbents and / or dispersants are added Preference is given to using in form.

Suitable liquid carriers are water, aliphatic hydrocarbons, aromatic hydrocarbons such as benzene, toluene and xylene, cyclohexanone, isophore, dimethylsulfoxide and dimethylformamide inorganic oil fractions.

Suitable solid carriers include tonsils, silica gels, talc, kaolin, etherclays, mineral soils such as limestone and silicates, and vegetable byproducts with wheat.

Surfactants include calcium lignin sulfonate, polyoxyethylene alkylphenol ethers, napresulfonic acid and salts thereof, phenolsulfonic acid and salts thereof, formaldehyde concentrates, fatty alcohol sulfates and substituted benzenesulfonic acids and salts thereof. have.

The total amount of active compounds and substances contained in the various herbicides can vary widely. For example, the formulation may contain approximately 10 to 80% by weight active material, 90 to 20% by weight liquid or solid carrier, and up to 20% by weight surfactant if necessary.

The active substance can be sprayed in a conventional manner, for example, with a spray solution of about 100 to 1000 liters per hectare using water as a carrier, and the active substance can be sprayed in so-called low volume methods and ultra-small sprays or in the form of particulates. .

In general formula (I) representing the compound of the present invention, R ₁ represents hydrogen, methyl, ethyl, n-propyl, isopropyl, n-butyl, secondary-butyl, isobutyl, tert-butyl, allyl, propenyl, propi Nil, butenyl, butynyl or methoxy groups and R ₂ and R ₃ are each hydrogen, methyl, ethyl, n-propyl, isopropyl, n-butyl, secondary-butyl, isobutyl or tert-butyl groups Indicates.

R ₄ and R ₅ represent fluorine, chlorine or bromine.

If n is 2, x represents the same or different two substituents. x represents hydrogen, methyl, ethyl, n-propyl isopropyl, n-butyl, secondary-butyl, isobutyl or tert-butyl group, fluorine, chlorine, bromine or iodine atom or methoxy group, respectively.

In the compounds of the present invention, R ₁ is methyl or methoxy group, R ₂ is hydrogen or methyl group, R ₃ is hydrogen or methyl group, R ₄ is chlorine or bromine, R ₅ is chlorine or bromine and x is each hydrogen Compounds of general formula (I), wherein methyl is chlorine or methoxy and n is 1 or 2, show particularly excellent herbicidal action.

The compound of formula (I) of the present invention is prepared by reacting a compound of formula (II) with a carbamic acid halide of formula (III) in the presence of an acid binder.

In the above general formula

R _1, R _2, R _3, R _4, R _5, x and n are as described above and Hal represents halogen.

Solvents used in the reaction include inert aliphatic and aromatic hydrocarbons such as hexane, benzene and toluene; Hydrogen chloride carbonates such as methylene chloride, chloroform, carbon tetrachloride and dichloroethane; Ethers such as diethyl ether, tetrahydrofuran and dioxane; Ketones such as acetone and butanone; Nitriles such as acetonitrile; Dimethylformamide and hexamethylphosphate triamide.

As the acid binder, organic bases of tertiary amines such as triethylamine, pyridine and diethylaniline or inorganic bases such as oxides, hydroxides or carbonates of alkali and alkaline earth metals are suitable.

The reactants react at 0-150 ° C.

The aniline derivatives used as starting materials are prepared by etherifying the corresponding nitrophenols and then reducing the nitro groups by known methods, or conversely by first acylating the local and optionally aminophenols at the nitrogen atom and at the end of the ether It can also be prepared by the formation.

Some of the dihalocyclopropane derivatives used for etherification are known compounds and can be prepared by known methods.

It has been found that cheap starting materials can be used to easily produce the compounds in high yields. According to this new method, allyl halides of the following general formula consist of haloforms of the general formula CHR ₄ R ₅ Hal (where R ⁴ and R ⁵ are as described above and Hal is halogen) and, if necessary, diluted with an inert solvent In two phase systems, in the presence of a catalyst, it is reacted with an alkali metal hydroxide in the form of a solid or an aqueous solution.

In the above general formula

R ² and R ³ are as described above

Hal is halogen.

Surprisingly, the allyl halides used in this process are not or are slightly saponified due to alkali metal hydroxides.

As haloform, chloroform and bromoform are preferable, and as hydroxide, it is preferable to use sodium hydroxide as a 50% aqueous solution.

Suitable catalysts include onium compounds (eg quaternary ammonium, phosphonium, arsonium compounds) and sulfonium compounds.

Also suitable as polyglycol ethers are cyclic ethers such as 18-cron-6 and tertiary amines such as tributylamine. Preferred compounds are quaternary ammonium compounds such as benzyltriethylammonium chloride and tetrabutylammonium bromide .

The rate of quantification of the reactants is wide. The reaction is preferably carried out at 1 to 10 times the haloform and hydroxide in each case. 0.02 equivalents of catalyst is sufficient.

The reaction takes place at 20 and 100 ° C but is generally between 20 and 60 ° C. The reaction lasts 1 to 72 hours. Mixing needs to be done thoroughly throughout the reaction.

The dihalocyclopropane derivatives used as starting materials are surprisingly produced in this way in high yield and by technically simpler methods than known processes.

The phenylurea derivative of the present invention is a colorless: odorless crystalline substance, easily soluble in ethyl acetate, acetone and alcohol. Some of these are slightly soluble in benzene and practically insoluble in saturated hydrocarbons and water.

The following examples illustrate the invention in detail. Examples 1 and 2 relate to the preparation of the compounds of the invention and examples 3 and 4 illustrate the possible uses and good selective herbicidal action of the compounds of the invention.

Example 1

[1- [4- (2,2-Dichlorocyclopropylmethoxy) -phenyl] -3,3-dimethylurea]

＝1.5096)을 얻는다.2 g of benzyltriethylammonium chloride are added to 100 ml (1.16 moles) of 3-bromopropene dissolved in 600 ml of chloroform. 600 ml of 50% sodium hydroxide solution is added over 30 minutes with good stirring. When the temperature rises, it cools and maintains between 56 and 60 ° C. Stirring is continued at this temperature for 4 hours and 750 ml of chloroform and 750 ml of water are added. The organic phase was separated and, dried by evaporation, and the fraction was concentrated in vacuo to 1-bromomethyl-2,2-dichloro-butyl cyclopropanecarboxylate of 162g (boiling point: _13: 63 to 70 ℃;

= 1.5096).

Dissolve 70 g (0.5 mole) of 4-nitrophenol in 250 ml of dimethylformamide and stir 108 g (0.53 mole) of 1-bromomethyl-2,2-dichlorocyclopropane, 83 g of calcium carbonate and 1.5 g of iodide Add to sodium. The mixture is stirred at 90 ° C. for 2 hours, cooled, poured into water and extracted with ethyl acetate. The organic phase was washed with dilute sodium hydroxide solution and water, dried, evaporated, concentrated and the residue was crystallized with pentane to give 113 g of 4- (2,2-dichlorocyclopropylmethoxy) -nitrobenzene (melting point: 66-67 ° C.). To obtain.

108 g (1.73 moles) of hydrazine hydrate are dissolved in 500 ml of ethanol and 10 g of nickel catalyst is added. 113 g (0.43 mole) of nitro compound prepared above was added in small portions over 45 minutes. The temperature rises to 60 ° C. during the addition. The mixture is stirred for several hours, filtered and the filtrate is concentrated and poured into water. The mixture is extracted with ethyl acetate, dried, evaporated and concentrated. The yellow oil remaining on the back side is used for the next reaction without purification.

Yield: 96 g of 4- (2,2-dichlorocyclopropylmethoxy) -aniline. 20 g (0.086 mol) of 4- (2,2-dichlorocyclopropylmethoxy) -aniline are dissolved in 100 ml of pyridine and 8.7 ml of dimethylcarbamoylchloride is added dropwise over 5 minutes with stirring. The temperature rises to 53 ° C. during the addition. The mixture is stirred for 2 hours and concentrated to strong by evaporation in Tor 50. The residue was treated with ethyl acetate, washed once with water and once with 5% hydrochloric acid, evaporated, concentrated and crystallized with isopropyl ether to give 16 g of 1- [4- (2,2-dichlorocyclopropylmethoxy)-. Phenyl] -3,3-dimethylurea (melting point: 108 to 110 ° C).

Example 2

[1- [3- (2,2-Dichlorocyclopropylmethoxy) -phenyl] -3,3-dimethylurea]

17 g (0.094 mol) of 1,1-dimethyl dissolved in 22 g (0.108 mol) of 1-bromomethyl-2,2-dichlorocyclopropane, 16 g of calcium carbonate and 2 g of sodium iodide in 60 ml of dimethylformamide It is added to 3- (3-hydroxyphenyl) -urea and stirred at room temperature. After 20 hours, 6 g of 1-bromomethyl-2,2-dichlorocyclopropane and 5 g of potassium carbonate are further added and stirring is continued for 6 hours. The mixture was highly concentrated, treated with ethyl acetate, extracted with shaking with water, dried and crystallized from ethyl acetate / ether to give 19.9 g of the title product having a melting point of 140 to 142 ° C.

1,1-dimethyl-3- (3-hydroxyphenyl) -urea used as starting material is a known compound and can be prepared by known methods from 3-aminophenol and dimethyl carbamoylchloride.

In a similar manner as in Example 1 or 2, the following compounds can also be prepared.

Example 3

In carrying out a series of tests in a greenhouse, the compounds of the present invention specified in the following table are germinated in the genus Sinapis and Solanum (test plants) in the form of a water-soluble emulsion in which 5 kg of the active substance per hectare is dissolved in 500 liters of water per hectare. Spray before and after germination respectively. The results are evaluated after 3 weeks of treatment and represented by numbers ranging from 0 to 4, where 0 indicates no activity and 4 indicates that the plant is removed. As shown in the table, test plants were generally removed.

Example 4

A series of tests were carried out in the greenhouse, but the plants specified in the following table were tested after germination with a spread of 1 kg of active substance per hectare of reagents specified in the table. Reagents for this purpose are sprayed all over the plant in an aqueous emulsion using, in each case, 500 liters of water per hectare. In this case, too, after 3 weeks of treatment, the compound of the present invention showed excellent activity against weeds, while showing strong resistance to cultivated plants. Comparative agents did not exhibit this selectivity. The treatment results were evaluated and represented by a number in the range of 0 to 10, with 0 indicating complete removal of the plant and 10 indicating no harm.

0 = completely remove

10 = no harm

Claims (1)

A process for preparing a phenylurea derivative of the following general formula (I) characterized by reacting a compound of the following general formula (II) with a carbamic acid halide of the following general formula (III) in the presence of an acid binder.

Wherein R ₁ is hydrogen, alkyl of 1 to 4 carbon atoms, alkenyl of 2 to 4 carbon atoms, alkynyl or methoxy group of 2 to 4 carbon atoms, R ₂ is hydrogen, or an alkyl group of 1 to 4 carbon atoms and R ₃ is hydrogen or an alkyl group of 1 to 4 carbon atoms, R ₄ is halogen, R ₅ is halogen, x is hydrogen, an alkyl group of 1 to 4 carbon atoms, halogen, or methoxy group and n is 1 or 2 Hal represents a halogen atom.