JPH0243744B2 - PIRIDAJINONJUDOTAIOYOBISONOSEIHO - Google Patents

Description

[Detailed description of the invention]

The present invention is based on the following formula (): 4-chloro-5-hydroxy-2-
This invention relates to (3-trifluoromethylphenyl)-3(2H)pyridazinone and its production method. The compound represented by the above formula () (hereinafter simply referred to as the compound of the present invention) is the compound represented by the following formula (): (In the formula, X represents a hydrogen atom, a lower alkyl group, or a halogen atom, and Y represents a hydrogen atom, a lower alkyl group, a halogen atom, or a nitro group.) It is the body. The reaction formula for producing a useful new compound () from the compound () of the present invention is as follows. (In the above reaction formula, Z means a halogen atom, methanesulfonyloxy group or p-toluenesulfonyloxy group, and X and Y have the same meanings as above.) Conventionally, pyridazinone derivatives are as follows. Compounds and methods for their production are known. [Chemical Abstract
Abstract) Volume 78 159646X] (In the formula, R is -CH ₃ ,

[Formula] or −CH ₂ CH=C〈 ^CH _3Cl . ) However, these known compounds are not known to be useful as intermediates for herbicides.
On the other hand, in the compound of the present invention, R in the above compound () is a substituted phenyl group, i.e.

[Formula] Since the compound of the present invention has this substituted phenyl group, it can be an excellent herbicide intermediate. On the other hand, the method for producing the compound of the present invention is shown in the following reaction formula. In the reaction formula, M represents an alkali metal atom. )
That is, the starting material () is heated and reacted in a water-containing lower alcohol in the presence of an alkali to obtain the intermediate material (). After the reaction is complete, remove the lower alcohol without isolating the intermediate (),
After making it acidic by adding acetic acid and removing impurities,
A mineral acid is added to obtain the compound of the present invention (). As the lower alcohol, for example, methyl alcohol, ethyl alcohol, etc. are preferable. As the alkali, for example, alkali metal hydroxides such as NaOH and KOH are preferable. As the mineral acid, hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, etc. can be used, but hydrochloric acid is particularly preferred. Next, examples of the method for producing the compound of the present invention and reference examples of the method for producing the active ingredient compound of a useful herbicide using the compound of the present invention as a raw material will be specifically described. However, it is not limited to these only. Example 1 Method for producing 4-chloro-5-hydroxy-2-(3-trifluoromethylphenyl)-3(2H)pyridazinone 17.6 g of KOH in 300 ml of 50% ethanol aqueous solution
(0.3 mol) of 4,5-dichloro-2-(3-trifluoromethylphenyl)-3 was dissolved at room temperature.
31 g (0.1 mol) of (2H) pyridazinone is added to the solution, and the suspended reaction mixture is heated at 60-65° C. for 2 hours, and after the raw materials are completely dissolved, it is refluxed for 4 hours. After cooling, ethanol was removed under reduced pressure.
After adding 200ml of water, acidify with acetic acid. After separating the insoluble matter, acidify the liquid with hydrochloric acid and remove the precipitated crystals.
Washed with water and recrystallized from ethanol, melting point 220-221℃
25g of the desired compound with the title was obtained. Yield 86% Starting compound 4,5-dichloro-2-(3-trifluoromethylphenyl)-3(2H)pyridazinone and product compound 4-chloro-5-hydroxy-2
The ¹³ C-NMR spectrum data of the carbon atom at the 6-position of each pyridazinone in -(trifluoromethylphenyl)-3(2H)pyridazinone is shown below. Note that the attribution of the ¹³ C signal was determined from the C-H COSY spectrum. (Solvent: DMSO-D ₆ , constant temperature 23℃) Starting compound 132.83ppm Product compound 136.72ppm When a hydroxyl group is attached to the ring, the chemical shift of ^13C at the ortho position moves to the high magnetic field, and the chemical shift of ^13C at the meta position moves to the high magnetic field. It is known as a rule of thumb that the chemical shift hardly changes or shifts slightly down the magnetic field, which indicates that the 5-position chlorine atom of the pyridazinone, rather than the 4-position chlorine atom, has been replaced by a hydroxyl group. Reference example 1 4-chloro-5-hydroxy-2-(3-trifluoromethylphenyl)-3 produced in Example 1
(2H) 0.012 mol of 4-methylbenzyl chloride was added to a mixture of 2.9 g (0.01 mol) of pyridazinone, 2.8 g (0.02 mol) of anhydrous potassium carbonate, and 20 ml of N,N-dimethylformamide, and the mixture was heated at 100 to 110°C with stirring. After heating for 1 hour and dissipating the heat, add 100ml of water.
The precipitated crystals were washed with water, air-dried, and then recrystallized from methanol to obtain 2.84 g of the title herbicide active ingredient (A) having a melting point of 149-150°C. Yield: 72% When applying the compound produced in Reference Example 1 (hereinafter simply referred to as the present compound (A)) as a herbicide, an appropriate carrier, such as a solid such as clay, talc, bentonite, or diatomaceous earth, is generally used. Carrier or water, alcohols (methanol, ethanol, etc.), aromatic hydrocarbons (benzene, toluene, xylene, etc.), chlorinated hydrocarbons, ethers, ketones, esters (ethyl acetate, etc.), acid amides It can be applied by mixing with a liquid carrier such as dimethylformamide (dimethylformamide, etc.), and if desired, emulsifiers, dispersants, suspending agents, penetrating agents, spreading agents, stabilizers, etc. can be added to form solutions, emulsions, and hydrated It can be put to practical use in any dosage form such as a powder, powder, or granule. In addition, if necessary, other types of herbicides, various insecticides, fungicides, synergists, etc. may be mixed and applied at the time of formulation or spraying. Other herbicides mentioned above include, for example, the Weed Control Handbook (Weed
Control Handbook, Volume 1, 6th Edition (1977), Volume 2, 8th Edition (1978) and Herbicide Handbook of the Weed Science Society of America, 4th Edition, 1979. the Weed science
These include compounds listed in the Society of America (Fourth Edition 1979). Next, a specific formulation of the herbicide composition of the present compound (A) will be shown as a formulation example. In addition, in the following formulation examples, parts mean parts by weight. Formulation example 1 Hydrating agent Compound (A) 50 parts Siegrite A (trade name) 46 parts Solpol 5039 (surfactant, manufactured by Toho Chemical Co., Ltd.) 2 parts Carplex (anti-caking agent, manufactured by Shionogi & Co., Ltd.)
Mix and grind 2 or more parts uniformly to make a wettable powder. When used, the above-mentioned hydrating agent is diluted 50 to 1,000 times with water and sprayed so that the amount of active ingredient is 5 to 1,000 g per 10 ares. Formulation example 2 Granules Compound (A) 8 parts Bentonite 50 parts Talc 42 parts After uniformly mixing and pulverizing the above, add a small amount of water, stir and mix, granulate with an extrusion granulator, and dry. and make into granules. In addition, this compound (A) can be applied to control various weeds in agricultural and horticultural areas such as fields, paddy fields, and orchards, as well as in non-agricultural areas such as playgrounds, vacant lots, and railway edges. Situation, application period,
There are differences depending on the application method, target grass species, cultivated crops, etc., but in general, the amount of active ingredients is 5 per 10 ares.
~1000g is appropriate. Next, the usefulness of the present compound (A) as a herbicide will be specifically explained in the following test examples. Test example 1 Weeding effect test by soil treatment A sterilized diluvial soil was placed in a plastic box measuring 15 cm in length, 22 cm in width, and 6 cm in depth.
Cyperus japonica, Coa japonica, Purslane, Purslane, Cucifera japonica, and Japanese dogwood were mixedly sown, the soil was covered with approximately 1.5 cm of soil, and the amount of active ingredient was uniformly spread over the surface of the soil at a predetermined ratio. The chemical solution used for spraying was the wettable powder of the formulation example described above diluted with water and sprayed over the entire surface with a small sprayer. Three weeks after spraying the chemical solution, the herbicidal effect on various weeds was investigated according to the following criteria. The results are shown in Table 2. Judgment Criteria 5...Weed killing rate 90% or more (almost complete death) 4...Weed killing rate 70-90% 3...Weed killing rate 40-70% 2...Weed killing rate 20-40% 1...Weed killing rate 5-20% 0...Weed killing rate 5% or less (almost no effect) However, the above weed killing rate was determined by the following formula by determining the weight of above-ground plants in the chemically treated area and the weight of above-ground plants in the non-treated area. Weed killing rate (%) = (1 - Weight of above-ground plants in treated area / Weight of above-ground plants in non-treated area) x 100 Test example 2 Phytotoxicity test on cultivated plants by soil treatment 15cm long, 22cm wide, 6cm deep A sterilized diluvial soil was placed in a plastic box, and rice, soybean, cotton, and wheat were sown, the soil was covered with approximately 1.5 cm of soil, and the amount of active ingredients was evenly spread over the soil surface at a predetermined ratio. The chemical solution used for spraying was the wettable powder of the formulation example described above diluted with water and sprayed over the entire surface with a small sprayer. Three weeks after the chemical spraying, the crops were examined for chemical damage according to the following criteria. The results are shown in Table 3. Judgment Criteria 5...Crops are almost completely dead 4...Significant phytotoxicity to crops 3...Drug damage to crops is observed 2... 〃 Some chemical solution is observed 1... 〃 〃 Almost no phytotoxicity is observed 0...〃 〃 Phytotoxicity is observed Not able to

【table】

[Table] As is clear from Tables 2 and 3, this compound (A) not only kills various weeds, but also kills rice and
It has no phytotoxic effects on wheat, soybeans, and cotton, and can be applied to these cultivated plants. Test Example 3 Weeding effect test under flooded conditions (1) After placing a jar of alluvial soil in a 1/10000 are Neubauer pot, add tap water and mix to create a flooded condition with a water depth of 2 cm. Seeds of Japanese millet, Japanese aquarium, azalea, azalea, and firefly are mixed in the above pots, and at the same time, 2.5 rice plants are transplanted to a depth of 1 cm. One day later, a diluted chemical solution is added to the water surface in a predetermined amount. Dispense with a graduated pipette. Two weeks after dropping the chemical solution, the herbicidal effect on various weeds was investigated according to the criteria of Test Example 1. The results are shown in Table 4. Test Example 4 Weeding effect test under flooded conditions (2) Growing season treatment Place alluvial soil in a 1/5000 are Wagner pot, then add tap water and mix to create a flooded condition with a water depth of 2 cm. Tainubier, Konagi, Azena,
Seeds of Kikashigusa and Firefly were mixed in the above pots, and 3, 3, 2, and 2 of Urikawa clump pods, Mizugaya tsurugi clump pods, and Kurogwai clump pods collected from paddy fields with many perennial weeds in the previous year were planted under the above-mentioned waterlogging conditions. Plant in soil in Wagner pots for each condition. After 10 days, that is, after the weeds have germinated, a diluted drug solution is dropped onto the water surface using a volumetric pipette to a predetermined dose. Three weeks after dropping the chemical solution, the herbicidal effect on various weeds was investigated according to the criteria of Test Example 1. The results are shown in Table 5.

[Table] * Pyrazolate is a commercially available herbicide, and its active ingredient compounds are listed below.
Street.

[Table] As is clear from Table 4, this compound (A) is
Compared to norflurazone, no phytotoxicity to rice was observed. On the other hand, it is clear from Table 5 that the compounds of the present invention have a greater herbicidal effect on firefly and other weeds than pyrazolate. Test Example 5 Test for phytotoxicity of rice under flooded conditions Fill a 1/10000 are Norbauer pot with alluvial soil, add water and mix to create a flooded condition with a water depth of 2 cm. Grown in a nursery box in advance
Rice (Nipponbare) at the 2.5-leaf stage was transplanted into the above Neubauer pot at 3 locations, 2 plants each, and 2 days later, a prescribed amount of diluted drug was dropped onto the water surface, and the growth status of the rice was observed 1 month later. investigated. The processing amount of this compound (A) is 40, 20 per are.
and 10g of each test plot. The results of these test plots showed that, compared to the untreated plot, the plant height and number of pods were almost the same, and no rolled leaves were observed, confirming that there was no chemical damage.

Claims (1)

[Claims] Primary formula (): 4-chloro-5-hydroxy-2-
(3-trifluoromethylphenyl)3-(2H)
Pyridazinone. Quadratic formula (): The following formula () is characterized in that the compound represented by is heated and reacted in a water-containing lower alcohol in the presence of an alkali, and then a mineral acid is added: 4-chloro-5-hydroxy-2-
A method for producing (3-trifluoromethylphenyl)-3(2H)pyridazinone.