CN1355163A - 3-(2-fluo-4,5,6-substituted phenyl)-1,3-benzopyrimidine-4-one compound with herbiciding activity - Google Patents

Abstract

3-(2-fluoro-4,5,6-substituted phenyl)-1,3-benzomeridin-4-one compounds with herbicidal activity, the general formula (I) of which is: I where: R ₁ is H, halogen, alkyl, haloalkyl, alkoxy, nitro, CN; _R2 is H, alkyl, haloalkyl; _X1 is halogen, alkyl, haloalkyl, alkoxy, nitro, CN ; _X2 is H, halogen, alkyl, haloalkyl, cycloalkyl, alkoxy, cycloalkoxy, alkenyloxy, alkynyloxy, alkoxycarbonyl, alkoxycarbonylalkoxy, alkoxycarbonylalkane Thio; X ₃ is H, halogen, alkyl, haloalkyl, alkoxy, nitro, CN; X ₁ and X ₂ and X ₂ and X ₃ can form a benzo 5- or 6-membered heterocycle.

Description

3-(2-fluoro-4,5,6-substituted phenyl)-1,3-benzopyrimidin-4-ones with herbicidal activity

The present invention belongs to the field of herbicides.

Because weeds develop resistance to herbicides or compositions thereof over time, there is a continuing need to invent new and improved herbicidal compounds and compositions. In addition, considering economical and environmental factors, it is also necessary to invent herbicides with different mechanisms of action from existing herbicides.

Certain 3-(2-fluorosubstituted phenyl)-1,3-benzopyrimidin-4-one compounds have been reported as fungicides, see EP183458. But in the above-mentioned patents, there is no report of its herbicidal activity. However, the 3-(2-fluoro-4,5,6-substituted phenyl)-1,3-benzopyrimidin-4-one compounds shown in the present invention have not been disclosed yet.

The object of the present invention is to provide a kind of new 3-(2-fluoro-4,5,6-substituted phenyl)-1,3-benzopyrimidin-4-one compounds; Another object of the present invention is to The compound and the composition thereof are used as broad-spectrum herbicides, and can be used before and after emergence to effectively control monocotyledons and dicotyledonous weeds. The present invention also relates to methods of preparing these compounds, using these compounds and compositions thereof for herbicidal purposes.

The general formula of the compound provided by the present invention is as follows:

in:

R ₁ is H, halogen, (C ₁ -C ₄ )alkyl, halo(C ₁ -C ₃ )alkyl, (C ₁ -C ₃ )alkoxy, halo(C ₁ -C ₃ )alkane Oxygen, Nitro, CN;

R ₂ is H, (C ₁ -C ₄ ) alkyl, halo (C ₁ -C ₃ ) alkyl;

X ₁ is halogen, (C ₁ -C ₆ ) alkyl, halo (C ₁ -C ₆ ) alkyl, (C ₁ -C ₆ ) alkoxy, nitro, CN;

X ₂ is H, halogen, (C ₁ -C ₆ ) alkyl, halo (C ₁ -C ₆ ) alkyl, (C ₁ -C ₆ ) cycloalkyl, (C ₁ -C ₆ ) alkoxy , (C ₃ -C ₆ ) cycloalkoxy, (C ₂ -C ₆ ) alkenyloxy, (C ₃ -C ₆ ) alkynyloxy, (C ₁ -C ₄ ) alkoxycarbonyl, (C ₂ - C ₆ )alkenyloxycarbonyl, (C ₃ -C ₆ )alkynyloxycarbonyl, (C ₁ -C ₆ )alkylsulfonylamino, (C ₁ -C ₆ )alkylsulfonyl(C ₁ -C ₂ )alkane Amino, (C ₁ -C ₄ )alkoxycarbonyl(C ₁ -C ₂ )alkoxy, (C ₁ -C ₄ )alkoxycarbonyl(C ₁ -C ₂ )alkylthio;

X ₃ is H, halogen, (C ₁ -C ₄ ) alkyl, halo (C ₁ -C ₃ ) alkyl, (C ₁ -C ₃ ) alkoxy, nitro, CN;

其中：When X _is H, X _{and X} can form a benzo 5- or 6-membered heterocycle as shown below:

in:

L is O, S;

R ₃ is H or (C ₁ -C ₄ ) alkyl;

R ₄ is H, (C ₁ -C ₆ )alkyl, halo(C ₁ -C ₆ )alkyl, (C ₁ -C ₆ )cycloalkyl, (C ₃ -C ₆ )alkenyl, halo (C ₃ -C ₆ )

Alkenyl, (C ₃ -C ₆ )alkynyl, halo(C ₃ -C ₆ )alkynyl, (C ₁ -C ₆ )alkoxy(C ₁ -C ₂ )alkyl, (C ₂ -C ₆ ) alkene oxide (C ₁ -C ₂ )

Alkyl, (C ₃ -C ₆ )alkynyloxy(C ₁ -C ₂ )alkyl, cyano(C ₁ -C ₆ )alkyl;

R ₅ is H, fluorine, (C ₁ -C ₃ ) alkyl;

其中：When X ₁ is CN, halogen, X ₂ and X ₃ can form a benzo 5-membered heterocycle as shown below:

in:

Y is O, S or -NR ₉ ;

Y' is Y or -CO;

R ₆ , R ₇ , R ₈ are H, halogen, CN, (C ₁ -C ₆ ) alkyl, (C ₃ -C ₆ ) cycloalkyl, (C ₂ -C ₆ ) alkenyl, (C ₃ - C ₆ ) alkynyl,

Halo(C ₁ -C ₆ )alkyl, (C ₁ -C ₆ )alkoxy, (C ₁ -C ₆ )hydroxyalkyl, -CO ₂ R ₁₀ , aldehyde, (C ₁ -C ₆ ) Alkylcarbonyl,

(C ₁ -C ₆ )alkylthio, (C ₁ -C ₆ )alkylsulfinyl, (C ₁ -C ₆ )alkylsulfonyl, halo(C ₁ -C ₆ )alkylthio,

Halo(C ₁ -C ₆ )alkylsulfonyl, halo(C ₁ -C ₆ )alkylsulfinyl;

R ₉ and R ₁₀ are respectively H, (C ₁ -C ₆ ) alkyl, (C ₃ -C ₆ ) alkenyl, (C ₃ -C ₆ ) alkynyl;

and its salt preparations.

More preferred compound among the present invention is, in the compound represented by general formula I:

_R1 is H;

R ₂ is H, (C ₁ -C ₃ ) alkyl or halo (C ₁ -C ₃ ) alkyl;

X ₁ is halogen, halogenated (C ₁ -C ₆ ) alkyl, nitro or CN;

X ₂ is halogen, halo(C ₁ -C ₆ )alkyl, (C ₁ -C ₆ )alkoxy, (C ₃ -C ₆ )cycloalkoxy, (C ₂ -C ₆ )alkenyloxy , (C ₃ -C ₆ ) alkynyloxy, (C ₁ -C ₄ ) alkoxycarbonyl, (C ₂ -C ₆ ) alkenyloxycarbonyl, (C ₃ -C ₆ ) alkynyloxycarbonyl, (C ₁ -C ₆ ) Alkylsulfonylamino, (C ₁ -C ₆ ) Alkylsulfonyl (C ₁ -C ₂ ) Alkylamino or (C ₁ -C ₄ ) Alkoxycarbonyl (C ₁ -C ₂ ) Alkoxy ;

_X3 is H;

其中：X _{and X} can also form a benzo 5- or 6-membered heterocycle as shown below:

in:

L is O;

R ₃ is H or (C ₁ -C ₃ ) alkyl;

R ₄ is (C ₁ -C ₅ ) alkyl, halo (C ₁ -C ₅ ) alkyl, (C ₁ -C ₅ ) cycloalkyl, (C ₃ -C ₅ ) alkenyl, halo (C ₃ -C ₅ )

Alkenyl, (C ₃ -C ₅ )alkynyl, halo(C ₃ -C ₅ )alkynyl, (C ₁ -C ₄ )alkoxy(C ₁ -C ₂ )alkyl, (C ₂ -C ₅ ) alkene oxide (C ₁ -C ₂ )

Alkyl, (C ₃ -C ₆ )alkynyloxy(C ₁ -C ₂ )alkyl, cyano(C ₁ -C ₅ )alkyl;

R ₅ is H, fluorine, (C ₁ -C ₃ ) alkyl;

and its salt preparations.

More preferred compound among the present invention is following two-part compound, and the first part is in the compound shown in general formula (I):

_R1 is H;

_X3 is H;

R ₂ is H, (C ₁ -C ₃ ) alkyl or halo (C ₁ -C ₃ ) alkyl;

X ₁ is halogen, halogenated (C ₁ -C ₆ ) alkyl, nitro or CN;

X ₂ is halogen, halo(C ₁ -C ₆ )alkyl, (C ₁ -C ₆ )alkoxy, (C ₃ -C ₆ )cycloalkoxy, (C ₂ -C ₆ )alkenyloxy , (C ₃ -C ₆ )

Alkynyloxy, (C ₁ -C ₄ )alkoxycarbonyl, (C ₂ -C ₆ )alkenyloxycarbonyl, (C ₃ -C ₆ )alkynyloxycarbonyl or (C ₁ -C ₄ )alkoxycarbonyl (C ₁ -C ₂ )

alkoxy;

and its salt preparations.

其中：The second part of the compound is that when R ₁ , R ₂ , and X ₃ are H, X ₁ and X ₂ can form a benzo 6-membered heterocycle as shown below;

in:

R ₄ is (C ₁ -C ₆ ) alkyl, halo (C ₁ -C ₅ ) alkyl, (C ₁ -C ₅ ) cycloalkyl, (C ₃ -C ₅ ) alkenyl, halo (C 5 ) ₃ -C ₅ )

Alkenyl, (C ₃ -C ₅ )alkynyl, halo(C ₃ -C ₅ )alkynyl, (C ₁ -C ₄ )alkoxy(C ₁ -C ₂ )alkyl, (C ₂ -C ₅ ) alkene oxide (C ₁ -C ₂ )

Alkyl, (C ₃ -C ₅ )alkynyloxy(C ₁ -C ₂ )alkyl, cyano(C ₁ -C ₅ )alkyl;

and its salt preparations.

Salt preparations of the compounds of the present invention can be formed by mixing the compounds of the present invention with organic acids such as acetic acid, inorganic acids such as hydrochloric acid and metal salts thereof (such as zinc chloride or ferric chloride).

The so-called alkyl refers to straight chain or branched chain form, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl, isopentyl Groups such as n-hexyl groups. Cycloalkyl refers to groups including cyclic chain forms, such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl and the like. Haloalkyl refers to a group in which the alkyl group is substituted with one or more halogen atoms. Alkylsulfonylalkyl refers to a group substituted by alkylsulfonyl (alkyl-SO ₂ ) on the alkyl group, such as methylsulfonylmethyl group. Alkylsulfinylalkyl means that there are alkylsulfinyl (alkyl-SO) substituent groups on the alkyl group, such as methylsulfinylmethyl and other groups.

The so-called alkenyl group refers to a straight chain or branched group with 1 to 2 carbon-carbon double bonds, such as vinyl, propenyl, allyl and the like.

The so-called alkynyl refers to a straight-chain or branched group with 1 to 2 carbon-carbon triple bonds, such as ethynyl, propynyl, propargyl and the like.

The so-called alkoxy refers to a straight or branched chain with an oxygen atom at the end, such as methoxy, ethoxy, n-propoxy, isopropoxy, tert-butoxy and the like.

The so-called alkylthio group refers to a straight chain or branched chain with a sulfur atom at the end, such as methylthio, ethylthio and the like.

The so-called halogen refers to fluorine, chlorine, bromine and iodine.

General formula compound (I) of the present invention can be prepared by following method:

method 1:

Benzoyl chloride (II) reacts with aniline (III) in a suitable solvent at a temperature ranging from -10°C to boiling point for 0.5-48 hours to prepare intermediate (IV). The solvent can be chloroform, dichloromethane, carbon tetrachloride, hexane, benzene, toluene, ethyl acetate, DMF, THF or dioxane, etc. In some cases, alkaline substances can be added, such as triethylamine, pyridine, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, etc.

Aniline (III) can be prepared by known methods, for example: can be purchased from the market or can be prepared by known methods of substituted nitrobenzene, react with reducing agents such as iron, zinc, titanium or hydrogen (see description in the patent EP0083055A2 method), prepared in a suitable solvent at a temperature ranging from -10°C to boiling point for 0.5-48 hours. The solvent can be water, acetic acid, acetone, chloroform, methylene chloride, carbon tetrachloride, hexane, benzene, toluene, ethyl acetate, ethanol, DMF, THF or dioxane, and a combination of two or three of the above Mixed solvents composed of solvents, etc.

Intermediate (V) can be obtained by referring to the preparation method of aniline.

The intermediate (V) is reacted with an acid anhydride such as R ₂ CO ₂ COCH ₃ in a suitable solvent or using an acid anhydride as a solvent at -10°C to boiling point for 0.5-48 hours to obtain the target compound (I). The solvent can be chloroform, dichloromethane, carbon tetrachloride, hexane, benzene, toluene, acetic acid, ethyl acetate, DMF, THF or dioxane, etc. Method 2:

Intermediate (VI) is reacted with aniline (III) in a suitable solvent at a temperature ranging from -10°C to boiling point for 0.5-48 hours to prepare intermediate (VII). The solvent can be chloroform, dichloromethane, carbon tetrachloride, hexane, benzene, toluene, ethyl acetate, DMF, THF or dioxane, etc. In some cases, alkaline substances can be added, such as triethylamine, pyridine, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, etc.

The intermediate (VII) reacts with PCl ₃ in a suitable solvent or with PCl ₃ as a solvent at -10°C to boiling point for 0.5-48 hours to obtain the target compound (I). The solvent can be chloroform, dichloromethane, carbon tetrachloride, hexane, benzene, toluene, ethyl acetate, DMF, THF or dioxane, etc. Intermediate (VII) is reacted at room temperature to boiling point for 0.5-48 hours in mineral acid such as hydrochloric acid, or adding a suitable solvent to prepare intermediate (V). The solvent can be chloroform, dichloromethane, carbon tetrachloride, hexane, benzene, toluene, ethyl acetate, DMF, THF or dioxane, etc. Method 3:

Novel compounds belonging to the general formula I can be prepared from compound (I-1). For example, compound (I-1) can be reacted with alkyl halide or alkyl sulfonate under basic conditions in a suitable solvent at a temperature ranging from -10°C to boiling point for 0.5-48 hours to obtain compound (I-2). The solvent can be acetone, chloroform, dichloromethane, carbon tetrachloride, hexane, benzene, toluene, ethyl acetate, DMF, THF or dioxane, etc. The base is triethylamine, pyridine, sodium hydroxide, hydrogen Potassium oxide, sodium carbonate, potassium carbonate, sodium bicarbonate and sodium hydride, etc.

Table 1, Table 2 and Table 3 list some compounds of the present invention represented by general formula (I).

The compound of the present invention shown in the general formula I in part of table 1 Compound R ₁ R ₂ X ₁ X ₂ X ₃ mp(°C)1 H H Cl H H 207-2092 H H Cl Propargyloxy H 206-2073 H CH ₃ Cl Propargyloxy H 129-1314 H CH ₃ Cl H H 132 -1355 H CF ₃ Cl H H 107-1096 7-Cl H Cl Propargyloxy H 2507 8-Cl H Cl Propargyloxy H 203-205

The compound of the present invention shown in general formula I in part of table 2 Compound R ₂ R ₄ mp(°C)8 CH ₃ propargyl wax 9 H H >25010 H propargyl 202-20411 H CH ₂ CH ₂ F 195-197

化合物          R₄          mp(℃)12            H            25013            CH₃         239-24114            炔丙基       155-156The compound of the present invention shown in the general formula I in part of table 3

Compound R ₄ mp(℃)12 H 25013 CH ₃ 239-24114 propargyl 155-156

The present invention also includes 3-(2-fluoro-4,5,6-substituted phenyl)-1,3-benzopyrimidine-1,3-benzopyrimidine- A 4-keto compound herbicidal composition.

Another embodiment of the present invention is a method of controlling weeds, the method comprising a herbicidally effective amount of a compound represented by general formula (I) and an acceptable carrier containing 3-(2-fluoro-4,5,6- The herbicidal composition of substituted phenyl)-1,3-benzopyrimidin-4-ones is applied to the weeds or the site of the weeds or the surface of the growth medium of the weeds.

The 3-(2-fluoro-4,5,6-substituted phenyl)-1,3-benzopyrimidin-4-one compound and its composition of the present invention can be used as pre-emergence and post-emergence herbicides.

The compounds of the invention can be applied to the soil or foliage in the form of formulations. Such compounds are usually dissolved in a carrier or formulated to facilitate dispersion for use as herbicides. For example: These chemical preparations can be made into wettable powders, concentrated emulsions, powders, suspensions, aerosols or emulsifiable concentrates. In these compositions, a liquid or solid carrier is added and, when desired, suitable surfactants may be incorporated.

Usually, especially when spraying on foliage, it is practically desirable to include adjuvants in the composition, such as wetting agents, spreaders, dispersants, sticking agents, adhesives and the like. Adjuvants of this type commonly used in the art can be found in the John W. McCutcheon, Company publication Detergents and Emulsifiers, Annual. Allured Publishing Company, Ridgewood, New Jersey, U.S.A.

The 3-(2-fluoro-4,5,6-substituted phenyl)-1,3-benzopyrimidin-4-one compound herbicidal composition of the present invention can be applied in the form of herbicide spray by common methods, Examples include conventional high-volume hydraulic spray, low-volume hydraulic spray, air spray, aircraft spray or dusting. Dilution and amount will depend on the type of equipment used, the method of application and the weeds to be controlled, but usually the more suitable effective amount is 10 grams to 3000 grams per hectare, and the preferred effective amount is 50 grams to 1500 grams per hectare .

The 3-(2-fluoro-4,5,6-substituted phenyl)-1,3-benzopyrimidin-4-one herbicidal composition of the present invention can be mixed with fertilizers before application. In a class of solid fertilizer compositions using said 3-(2-fluoro-4,5,6-substituted phenyl)-1,3-benzopyrimidin-4-one compounds, fertilizer or Fertilizing components, such as ammonium sulfate, ammonium nitrate or ammonium phosphate, are coated with one or more compounds. Said solid compounds or solid fertilizers may also be mixed in mixing equipment, or they may be combined with fertilizers to form granular compositions. The fertilizer can be used in any proportion, but the proportion of the so-called 3-(2-fluoro-4,5,6-substituted phenyl)-1,3-benzopyrimidin-4-one compound in its fertilizer composition About 5% to 25%. These compositions control the growth of undesired vegetation while providing fertilizer to promote the growth of desired crops. The compounds of the present invention may be present in the form of compositions or formulations. For methods of preparing preparations or compositions, reference can be made to "Research on Pesticide Formulations" (published in 1969) published by the American Chemical Society or "Pesticide Formulations" (published in 1973) in the series of advances in chemistry. The so-called formulation refers to the mixture of the active ingredient and the solid carrier and the liquid carrier of the diluent or dispersant suitable for agricultural technology. Carriers refer to ingredients that have emulsifying, dispersing and diluting effects, do not damage the effect of active components, and have no impact on soil, equipment, crops and agricultural environments. Sometimes it is necessary to add additives such as surfactants, stabilizers, defoamers agent or anti-sedimentation agent.

So-called compositions or formulations are, for example, aqueous solutions or dispersions, oil solutions or dispersions, pastes, powders, wettable powders, emulsion concentrates, granules, attractants, aerosols, and the like. Wettable powders, concentrates, and pastes are formulated in high concentrations and diluted with water before use. These formulations may contain liquid or solid carriers and, if desired, surfactants may be added.

When preparing foliar spray preparations, it is usually necessary to add adjuvants such as wetting agents, spreading agents, dispersants, adhesives or thickeners to improve the application effect. Commonly used adjuvants and methods of use are described in many documents. For example the Handbook of Detergents and Emulsifiers.

In the composition of the present invention, the weight percentage of active components is between 0.1-99%. For the convenience of transportation and storage, the suitable weight percentage is between 0.5-90%, and the more suitable weight percentage is between 1-75%. Compositions can also be expressed in terms of ratios of compound and carrier.

Usually the compounds of the present invention can be dissolved in specific solvents such as acetone, methanol, ethanol, dimethylformamide, pyridine or dimethyl sulfoxide and then diluted with water, and its concentration can vary from 1% to 90%, more It is suitably 5% to 50%.

To prepare a concentrated emulsion, the compound of the present invention can be dissolved in one or several mixed solvents, and then an emulsifier is added to enhance the dispersion effect of the compound in water. Concentrates typically contain between 10% and 90% active ingredient.

To prepare wettable powders suitable for spraying, the compounds of the invention may be mixed with finely divided solid powders such as clays, inorganic silicates, carbonates and wetting, binding and or dispersing agents. The active ingredient is usually between 20% and 99%, more suitably between 45% and 75%. For example a typical 50% wettable powder is 50 parts of the compound of the invention, 45 parts of silicate and 5 parts of sodium lignosulfonate.

Dusts are prepared by mixing a compound of the invention with a finely divided inert solid powder. Suitable solid powders are vegetable flours, silicates, carbonates or clays. A convenient method is to dilute the wettable powder with finely ground solid powder. Powders generally contain between 20% and 80% active ingredient and are subsequently diluted to a use concentration of 1% to 10%.

The compounds of the present invention can be used alone or in combination with other known insecticides, fungicides, herbicides, plant growth regulators or fertilizers.

For some applications, one or more other herbicides may be added to the herbicides of the present invention, thereby providing additional advantages and effects. When mixtures of herbicides are used, the relative proportions employed will depend upon the relative efficacy of the mixture on the plants to be treated. When mixtures of herbicides are used, the relative amounts used will depend on the crop being treated and the degree of selectivity in weed control desired.

It should be apparent that various changes and modifications can be made without departing from the scope of the present invention defined in the claims.

The following examples, bioassay results and tables serve to further illustrate the present invention, but are not meant to limit the scope of the invention as indicated by the claims.

Synthetic example

Example 1, the preparation of compound 9:

Under cooling in an ice-water bath, a solution formed of 2-nitrobenzoyl chloride (2.04 g, 90%, 10 mmol) and dichloromethane (20 ml) was added dropwise to 7-fluoro-6-amino-4H-1 within 10 minutes. , 4-Benzoxazin-3-one (1.78 g, 10 mmol) and triethylamine (1.1 g, 11 mmol) in a mixture of dichloromethane (20 mL), stirred overnight at room temperature. The reaction mixture was poured into water, and the sinking solid was collected by filtration, washed with hexane and water respectively, and dried to obtain 7-fluoro-6-(2-nitrobenzoyl)amino-4H-1,4-benzoxa Azin-3-one (2.9 g, 92% yield), melting point: >248°C.

Under cooling in an ice-water bath, zinc powder (1.5 g, 16 mmol) was added in portions to 7-fluoro-6-(2-nitrobenzoyl)amino-4H-1,4-benzoxazine-3 within 15 minutes. - In a mixture of ketone (1.1 g, 3.4 mmol), 2N ammonium chloride (15 ml, 27 mmol), THF (25 ml), stir at room temperature for 3 hours. The reaction mixture was poured into water, and the insoluble solid was removed by filtration. The solid was washed with ethyl acetate and water respectively. The filtrate was extracted with ethyl acetate, washed with water and saturated saline solution, and dried over anhydrous sodium sulfate. Removal of the solvent gave 7-fluoro-6-(2-aminobenzoyl)amino-4H-1,4-benzoxazin-3-one (0.7 g, yield 70%), melting point: 251-252°C .

A mixture of 7-fluoro-6-(2-aminobenzoyl)amino-4H-1,4-benzoxazin-3-one (0.7 g, 2.3 mmol) and HCO ₂ COCH ₃ (10 mL) was heated Refluxed for 5 hours, the reactant was cooled to room temperature and poured into ice (20 g), the precipitated solid was collected by filtration, washed with water, and dried to obtain 3-[7-fluoro-4H-1,4-benzoxazine- 3-keto-6-]-1,3-benzopyrimidin-4-one (0.5 g, 70% yield), melting point: >250°C.

Example 2, the preparation of compound 10:

Sodium hydride (0.06 g, 60%, 1.5 mmol) was added to 3-[7-fluoro-4H-1,4-benzoxazin-3-one-6-]-1,3-benzo A solution of pyrimidin-4-one (0.31 g, 1 mmol) and DMF (15 mL) was stirred at room temperature for 10 minutes, and then propargyl bromide (0.25 g, 80%, 1.6 mmol) was added. Stirred at room temperature overnight. The reaction mixture was mixed with 100 mL of ethyl acetate, washed with water and saturated brine, and dried over anhydrous sodium sulfate. Removal of the solvent gave 3-[7-fluoro-4-(N-propargyl)-1,4-benzoxazin-3-one-6-]-1,3-benzopyrimidin-4-one ( 0.24 g, yield 69%), melting point: 202-204°C.

Other compounds can be prepared by similar methods as above.

Bioassay example

Pre-emergence test: after sowing, the test compound is sprayed on the soil surface, placed in the greenhouse after treatment, and then watered; post-emergence test, the seeds germinate and grow for 10-21 days, so that the test material has a series of growth stages before treatment , and then select the test materials with the same size and growth stage, and process them. After the treatment, they are placed in the greenhouse and watered. Samples not treated with compounds were used as controls.

Usually acetone is used to dissolve the original drug, or water is used to dissolve the preparation prepared by the aforementioned method. Spray with a mobile belt sprayer. The test material is placed on the rolling belt in the spray cabinet, and the nozzle is moved over the upper part of the test material to spray the agent on the test material in the form of fan spraying. The nozzle is the same as that on the usual field sprayer. Roll the test material out of the cabinet and place it in a drying oven to dry.

The spray-dried samples were placed in the greenhouse. The pre-emergence test was sprayed with water from the top, and the post-emergence test was irrigated with water from the bottom and kept for 48 hours so that the water did not touch the leaves.

Surveys were performed 2-3 weeks after treatment. Activity was graded from 0% (ineffective) to 100% (full control). The inhibition rate is the total effect of various damages such as chlorosis, rot, growth retardation or burning of leaf corners, and the results are obtained after comparison with the control. Some test results are shown in Table 4.

                                                                       

[Pre-emergence (1200g/ha)/post-emergence (1200g/ha)] compound BYG FOX MA Tom VEL 1 0/0 0/0 0/0 0/50 0/90 2 50/95 100/95 0/50 0/100 0/100 3 0/0 0/0 0/0 0/20 0/90 4 0/0 0/0 0/0 0/0 0/90 6 0/70 60/70 0/0 60/100 100/100 7 0/30 0/70 0/0 0/40 0/90 8 0/0 0/0 0/0 0/20 0/80 9 0/0 0/40 0/0 0/20 0/80 10 100/95 80/100 100/100 100/100 100/100 11 90/80 90/60 0/100 100/100 90/100 12 0/0 0/0 0/0 0/60 0/0 13 0/0 0/60 0/0 0/0 0/60

Table 5: Weed names Abbreviation common name Latin name BYG barnyard grass Echinochloa crus-galli FOX green dog tail Setaria viridis MA marigold Tagetes spp Tom tomato Lycopersicon esculentum VEL Abutilon Abutilon theophrasti

Claims (7)

1. a 3-(2-fluoro-4,5,6-substituted phenyl)-1,3-benzopyrimidin-4-one compound with herbicidal activity is characterized in that the title compound of the present invention (I ) has the general formula: in: R ₁ is H, halogen, (C ₁ -C ₄ )alkyl, halo(C ₁ -C ₃ )alkyl, (C ₁ -C ₃ )alkoxy, halo(C ₁ -C ₃ )alkane oxygen base, nitro or CN; R ₂ is H, (C ₁ -C ₄ ) alkyl or halo (C ₁ -C ₃ ) alkyl; X ₁ is halogen, (C ₁ -C ₆ ) alkyl, halo (C ₁ -C ₆ ) alkyl, (C ₁ -C ₆ ) alkoxy, nitro or CN; X ₂ is H, halogen, (C ₁ -C ₆ ) alkyl, halo (C ₁ -C ₆ ) alkyl, (C ₁ -C ₆ ) cycloalkyl, (C ₁ -C ₆ ) alkoxy , (C ₃ -C ₆ ) Cycloalkoxy, (C ₂ -C ₆ ) alkenyloxy, (C ₃ -C ₆ ) alkynyloxy, (C ₁ -C ₄ ) alkoxycarbonyl, (C ₂ -C ₆ ) alkenyloxycarbonyl, ( C ₃ -C ₆ ) Alkyneoxycarbonyl, (C ₁ -C ₆ )alkylsulfonylamino, (C ₁ -C ₆ )alkylsulfonyl(C ₁ -C ₂ )alkylamino, (C ₁ -C ₄ )alkoxycarbonyl (C ₁ -C ₂ )alkoxy or (C ₁ -C ₄ )alkoxycarbonyl(C ₁ -C ₂ )alkylthio; X ₃ is H, halogen, (C ₁ -C ₄ ) alkyl, halo (C ₁ -C ₃ ) alkyl, (C ₁ -C ₃ ) alkoxy, nitro or CN; When X _is H, X _{and X} can form a benzo 5- or 6-membered heterocycle as shown below:

in: L is O or S; R ₃ is H or (C ₁ -C ₄ ) alkyl; R ₄ is H, (C ₁ -C ₆ )alkyl, halo(C ₁ -C ₆ )alkyl, (C ₁ -C ₆ )cycloalkyl, (C ₃ -C ₆ )alkenyl, halo (C ₃ -C ₆ ) Alkenyl, (C ₃ -C ₆ )alkynyl, halo(C ₃ -C ₆ )alkynyl, (C ₁ -C ₆ )alkoxy(C ₁ -C ₂ )alkyl, (C ₂ -C ₆ ) alkene oxide (C ₁ -C ₂ ) Alkyl, (C ₃ -C ₆ )alkynyloxy(C ₁ -C ₂ )alkyl or cyano(C ₁ -C ₆ )alkyl; R ₅ is H, fluorine or (C ₁ -C ₃ ) alkyl; When X ₁ is CN or halogen, X ₂ and X ₃ can form a benzo 5-membered heterocycle as shown below: in: Y is O, S or -NR ₉ ; Y' is Y or -CO; R ₆ , R ₇ , R ₈ are H, halogen, CN, (C ₁ -C ₆ ) alkyl, (C ₃ -C ₆ ) cycloalkyl, (C ₂ -C ₆ ) alkenyl, (C ₃ - C ₆ ) alkynyl, Halo(C ₁ -C ₆ )alkyl, (C ₁ -C ₆ )alkoxy, (C ₁ -C ₆ )hydroxyalkyl, -CO ₂ R ₁₀ , aldehyde, (C ₁ -C ₆ ) Alkylcarbonyl, (C ₁ -C ₆ )alkylthio, (C ₁ -C ₆ )alkylsulfinyl, (C ₁ -C ₆ )alkylsulfonyl, halo(C ₁ -C ₆ )alkylthio, Halo(C ₁ -C ₆ )alkylsulfonyl or halo(C ₁ -C ₆ )alkylsulfinyl; R ₉ and R ₁₀ are respectively H, (C ₁ -C ₆ ) alkyl, (C ₃ -C ₆ ) alkenyl or (C ₃ -C ₆ ) alkynyl; and its salt preparations. 2. The compound of claim 1, characterized in that: _R1 is H; R ₂ is H, (C ₁ -C ₃ ) alkyl or halo (C ₁ -C ₃ ) alkyl; X ₁ is halogen, halogenated (C ₁ -C ₆ ) alkyl, nitro or CN; X ₂ is halogen, halo(C ₁ -C ₆ )alkyl, (C ₁ -C ₆ )alkoxy, (C ₃ -C ₆ )cycloalkoxy, (C ₂ -C ₆ )alkenyloxy , (C ₃ -C ₆ ) alkynyloxy, (C ₁ -C ₄ ) alkoxycarbonyl, (C ₂ -C ₆ ) alkenyloxycarbonyl, (C ₃ -C ₆ ) alkynyloxycarbonyl, (C ₁ -C ₆ ) Alkylsulfonylamino, (C ₁ -C ₆ ) Alkylsulfonyl (C ₁ -C ₂ ) Alkylamino or (C ₁ -C ₄ ) Alkoxycarbonyl (C ₁ -C ₂ ) Alkoxy ; _X3 is H; X _{and X} can also form a benzo 5- or 6-membered heterocycle as shown below: in: L is O; R ₃ is H or (C ₁ -C ₃ ) alkyl; R ₄ is (C ₁ -C ₅ ) alkyl, halo (C ₁ -C ₅ ) alkyl, (C ₁ -C ₅ ) cycloalkyl, (C ₃ -C ₅ ) alkenyl, halo (C ₃ -C ₅ ) Alkenyl, (C ₃ -C ₅ )alkynyl, halo(C ₃ -C ₅ )alkynyl, (C ₁ -C ₄ )alkoxy(C ₁ -C ₂ )alkyl, (C ₂ -C ₅ ) alkene oxide (C ₁ -C ₂ ) Alkyl, (C ₃ -C ₅ )alkynyloxy(C ₁ -C ₂ )alkyl or cyano(C ₁ -C ₅ )alkyl; R ₅ is H, fluorine or (C ₁ -C ₃ ) alkyl; and its salt preparations. 3. The compound of claim 2, characterized in that: X ₂ is halogen, halo(C ₁ -C ₆ )alkyl, (C ₁ -C ₆ )alkoxy, (C ₃ -C ₆ )cycloalkoxy, (C ₂ -C ₆ )alkenyloxy , (C ₃ -C ₆ ) Alkynyloxy, (C ₁ -C ₄ )alkoxycarbonyl, (C ₂ -C ₆ )alkenyloxycarbonyl, (C ₃ -C ₆ )alkynyloxycarbonyl or (C ₁ -C ₄ )alkoxycarbonyl (C ₁ -C ₂ ) alkoxy; and its salt preparations. 4. The compound as claimed in claim 2, characterized in that: R ₂ is H, X ₁ and X ₂ can form a benzo 6-membered heterocycle as shown below:

in: R ₄ is (C ₁ -C ₅ ) alkyl, halo (C ₁ -C ₅ ) alkyl, (C ₁ -C ₅ ) cycloalkyl, (C ₃ -C ₅ ) alkenyl, halo (C ₃ -C ₅ ) Alkenyl, (C ₃ -C ₅ )alkynyl, halo(C ₃ -C ₅ )alkynyl, (C ₁ -C ₄ )alkoxy(C ₁ -C ₂ )alkyl, (C ₂ -C ₅ ) alkene oxide (C ₁ -C ₂ ) Alkyl, (C ₃ -C ₅ )alkynyloxy(C ₁ -C ₂ )alkyl, cyano(C ₁ -C ₅ )alkyl; and its salt preparations. 5. A herbicidal composition, characterized in that the composition comprises the compound of claim 1 and an acceptable carrier thereof, wherein the weight percentage of the active component is 0.1-99%. 6. The application of the compound as claimed in claim 1 and the composition thereof in controlling weeds. 7. A method for controlling weeds, characterized in that the method comprises applying a herbicidally effective amount of the herbicidal composition as claimed in claim 5 to the weeds or the growth medium or site of the weeds.