JPS5967274A - Pyridazine derivative and selective herbicide - Google Patents

Abstract

NEW MATERIAL:The pyridazine derivative of formula I [R1 is Cl or organic group of formula OR3 (R3 is lower alkyl substituted with lower alkylthio or di(lower alkyl)amino, etc.); R2 is group of formula II (r3 is lower alkyl; r4 is lower alkyl or phenyl which may be substituted with lower alkylthio) or H; provided that when R1 is Cl, R2 is not H]. EXAMPLE:5-(2-Butylideneaminoxy)-4,6-dichloro-3-phenylpyridazine. USE:Useful as a herbicide. It exhibits high herbicidal effect against broad-leaved weeds especially goosefoot, barnyardgrass, smartweed, etc. at a low rate of application, and high selectivity to peanut, rice and wheat. It is harmless to man, animal, fish and shellfish. PROCESS:The compound of formula I can be prepared, e.g. by reacting 3-phenyl-4, 5,6-trichloropyridazine with the compound of formula III in a solvent in the presence of an acid acceptor.

Description

DETAILED DESCRIPTION OF THE INVENTION With regard to the novel compounds of the present invention and their uses, details can be found in the general formula [wherein R1 is a chlorine atom or OR, (R and 3 are substituted with a lower alkylthio group or a di-lower alkylamino group] lower alkyl group, lower alkoxycarbonylamino group,
a benzoylamino group, a di-lower alkylamino group, a benzenesulfonyl group with or without a substituent, or a formula CON<, (in the formula r.

2 represents a lower alkyl group; r represents a lower alkyl group or a lower alkoxy group; ) represents an amide group. ), R2 is an organic group represented by the formula 0N=C<r3 (in the formula r
, represents a lower alkyl group, and r4 represents a lower alkyl group or phenyl group which may be substituted with a lower alkyl group. ) or a hydrogen atom. However, when R is a chlorine atom, R7 is not a hydrogen atom. ]
It is a selective herbicide containing the compound represented by and the compounds as active ingredients.

An object of the present invention is to provide a herbicide that can be industrially advantageously obtained, is easy to use, and is highly effective.

The present inventors synthesized a large number of pyridazine derivatives and examined those suitable for the above purpose, and found that the general formula (I)
The inventors discovered that the compound represented by the following shows excellent herbicidal activity and has almost no toxicity to humans, animals, fish, and shellfish, and after conducting further biological and physicochemical research, they completed the present invention.

It was disclosed in JP-A-49-4 that phenylpyritazine derivatives similar to the compounds of the present invention have plant growth inhibiting and herbicidal effects.
No. 8837, No. 80245, No. 50-35339, etc., but the compound of the present invention has far superior herbicidal activity compared to known compounds.

51 Among the compounds of the present invention, compounds in which RI is a chlorine atom are 3-
Phenyl-4,5,6-)lichloropyridazine and a compound represented by the general formula HON=C<3 (in the formula, r3 and r4 have the same meanings as 4 above) in an inert solvent, It can be produced by reacting in the presence of an acid binder. As acid binders, pyridine, ditriethylamine, 18-diazafcyclo(5,4,0
)-7-Undecene and other organic amines, caustic soda,
Caustic potash, metallic sodium, sodium hydride, etc. are used. As the reaction solvent, common inert solvents such as alcohol, ether, benzene, toluene, tetrahydrofuran, dimethyl sulfoxide, and dimethyl formamide can be used. The reaction temperature is from room temperature to the boiling point of the solvent, preferably at room temperature or under mild heating conditions. After reacting for 30 minutes to several hours, the reaction solution is poured into ice water and the separated oil or crystals are separated by solvent extraction or filtration to obtain the desired product.

The compound of the present invention in which R1 in the general formula N) is an organic group other than a chlorine atom can be produced, for example, by the method shown in the reaction formula below.

(In the formula, Rs has the same meaning as above.) The method for producing the compound of the present invention will be explained in more detail below with reference to production examples.

Production Example 1 Compound 1 5-(2-butylideneaminooxy)-4,6-dichloro-3-phenylpyridazine 0.46.9 g of oily 60% sodium hydride was suspended in 40 ml of dry DMF and cooled with water. Add ethyl methyl ketone ochim 0.92.9 until hydrogen generation stops (
After stirring for about 15 minutes, 25 g of 3-phenyl-4,5,6-drichloropyridazine was added and stirred at room temperature for 2 hours. Thereafter, the mixture was poured into ice water, extracted with ether, and the solvent was distilled off. The resulting oil was purified by silica gel column chromatography (benzene:ethyl acetate - 9:1) to obtain the desired product 2.4.9. Yield 80% Colorless transparent oil n 1.6078 Production example 2. Compound 4 4-((ethoxycarbonylamino)oxy)-6-
Chloro-3-phenylpyridazine oily 60 sodium thihydride in dry DMF 501d 0
．． 5:1 was suspended, and while cooling with water, 1.54II of N-hydroxyurethane was added and stirred for about 15 minutes until hydrogen generation stopped. Then, 3 g of 4.6-dichloro-3-phenylpyridazine was added at room temperature, stirred overnight at room temperature, poured into ice water, extracted with ether, and the solvent was distilled off. Xane: Ethyl acetate-2
= 1) to obtain 2.7 g of the target product.

Yield: 70 White crystals m, p, 32-33°C Production example 3.
Compound 8 6-riocr-4-(N-methoxy-N-methylcarbamoyloxy)-3-phenylpyridazine dried DMF3
Oily 60% Sodium Hydride in 07117 0.471
1 was suspended and cooled with water to form 6-chloro-4-hydroxy-
After adding 2 g of 3-phenylpyridazine and stirring until hydrogen generation stopped (about 15 minutes), 1.5 g of N-methoxy-1'J-methylcarbamoyl chloride was added dropwise and the mixture was stirred at room temperature for 2 hours. Thereafter, the mixture was poured into ice water, extracted with ether, and the solvent was distilled off. The resulting residue was washed with n-hexane to obtain 1.3 g of the desired product. Yield 457 white crystals m, p,
7374°C production example 4. Compound 11゜6-chloro-4-(methylthio)methoxy-3-phenylpyridazine Dry DMF 5Qm/! 6-chloro-4-
After adding hydroxy-3-phenylpyridazine 3I and stirring until hydrogen generation stopped (about 15 minutes), chloromethyl methyl sulfide 1,6I was added dropwise and the mixture was stirred at room temperature for 2 hours. After that, it was poured into ice water and extracted with ethyl acetate, and the obtained oil was subjected to silica gel column chromatography (benzene:
Purification was performed using ethyl acetate (7:3) to obtain 2 g of the desired product.

Yield 51.6% light brown crystals m, p, 95-96°C Production Example 5. Compound 13゜6-Chloro-4-((N,N-diethylamino)oxy)-3-phenylpyridazine 1 m25Q6 In 30 mJ of DMF, 3 g of caustic soda aqueous solution was added, and N,N-diethylhydroxylamine (85% aqueous solution) was added under water cooling. After dropping .8 g of the mixture and stirring for 15 minutes, 3 g of 4,6-dichloro-3-phenylpyridazine was added and stirring was continued for 3 hours at room temperature.

It was poured into condensate water, extracted with chloroform, the solvent was distilled off, and the resulting residue was recrystallized from ligroin to obtain the desired product (0.7
I got g.

Yield 19% White crystals m, p, 91-92°C Production example 6. Compound 14゜6-chloro-4-tosyloxy-3-phenylpyridazine Dissolve 2.31 of 6-chloro-4-hydroxyV-3-phenylpyridazine in 20 ml of DMF, and add 0.5 g of caustic soda to 5 rat of water at room temperature. It was dissolved in and added.

Next, 1.9 g of tosyl chloride was added to the mixture at room temperature while stirring, and the mixture was reacted for 1 hour. The reaction solution was poured into ice water, a large amount of precipitated crystals were collected, and the crystals were recrystallized from methanol to obtain 35 g of white crystals of the desired product.

m969~70°C Table 1 shows the structural formulas and physical constants of the compounds of the present invention.

Table 1: When the compounds of the present invention are sprayed on the foliage of weeds during the growth period after germination, they exhibit high herbicidal effects, especially against broad-leaved weeds such as pigweed, four-legged weed, knotweed, and chickweed, even at a low dose. Moreover, for peanuts, almost no adverse effects are observed even when sprayed on the stems and leaves in an amount 2 to 4 times the amount used to kill weeds.
It has extremely high selectivity between weeds and peanuts.

This compound also has selectivity for rice and wheat, and in particular for rice, a low dose of 1001/10a, for example, can kill a wide range of paddy field weeds without causing any phytotoxicity to rice. It has this effect and has extremely high selectivity between rice and weeds.

The herbicide of the present invention comprises one of the compounds represented by the general formula CD.
or two or more as active ingredients, and has a form similar to that of ordinary agricultural chemicals. That is, the active ingredient compound is generally used by mixing appropriate ingredients with a carrier and preparing it in the form of a wettable powder, emulsion, granule, or the like. Examples of solid carriers include talc, white carbon, bentonite, clay, diatomaceous earth, etc., and examples of liquid carriers include water, alcohol, benzene, quinolene, kerosene, mineral oil, cyclohexane, cyclohexanone, dimethylformamide, and the like.

If necessary, a surfactant may be added in order to obtain a uniform and stable form in these preparations.

The concentration of the active ingredient in the herbicide of the present invention varies depending on the form of the preparation mentioned above, but for example, in a wettable powder, it is 5 to 70%, preferably 10 to 50%,
Concentrations of 5-40%, preferably 10-30% are used in emulsions.

The wettable powders and emulsions obtained in this way are diluted with water to a predetermined concentration to form a suspension or emulsion, which can be sprayed or mixed on the soil before weed germination, or on the foliage after weed germination. Sprayed. When actually applying the herbicide of the present invention, an appropriate amount of 30 g or more, preferably 501 i or more of the active ingredient is applied per 10 are.

In addition, the herbicide of the present invention is a known bactericide, insecticide, acaricide,
It can also be used in combination with herbicides, plant growth regulators, etc. In particular, when used in combination with herbicides, it is possible to not only reduce the number of medicinal animals used and save energy, but also to expect even higher effects due to the synergistic action of both drugs. Examples of drugs suitable for mixed use with the herbicide of the present invention include 2
-(1-allyloxyaminobutylidene) -5,5-
Dimethyl-4-methoxycarbonyl-cyclohexane-
Sodium salt of 1,3-dione (Fusagad), 2-(
N-ethquinzothyrimidoyl)-5-(2-ethylthiopropyl)-3-hydroxy-2-cyclohexene-1
Cyclohexanedione herbicides such as -one, phenoxyphenoxyalkanecarboxylic acid herbicides such as iloxane and alopex, butyl 2-(4-(6-)lifluoromethyl-2-pyridyloxy)phenoxy]propionate, etc. Examples include pyridyloxy-phenoxypropionic acid herbicides.

Next, some formulation examples regarding the herbicide of the present invention will be shown, but the ratio of active ingredients, types of additives, and addition ratios are not limited to the present formulation examples and can be varied within a wide range.

Formulation example 1 Hydrating agent compound number 8 40 parts
10 parts diatomaceous earth
10 parts white carbon 3
0 parts polyoxyethylene alkylaryl ether sulfonate 10 parts or more were uniformly mixed and finely ground to obtain a wettable powder containing 40% of the active ingredient.

Formulation example 2 Emulsion compound number 1 30 parts xylene
50 parts dimethylformamide 10 parts polyoxyethylene phenyl ether 10 parts were further mixed and dissolved to obtain an emulsion containing 30% of the active ingredient.

Formulation Example 3 Granules Compound Number 12 7 Parts Tarri 38
Department -
38 part bentonite
10 parts Sodium alkyl sulfate
After uniformly mixing 7 parts or more and pulverizing it finely,
Granulated into granules with a diameter of 0.5 to 1.0 tl and contains 7% active ingredient.
granules were obtained.

Next, test examples regarding the effect of the herbicide of the present invention will be shown.

Test Example 1 Efficacy Test A 200 cJ pot was filled with soil 7, and seeds of surface layer ζ niakaza, snail, and chickweed were sown and grown in a greenhouse. When each weed grows to a height of about 3 to 8 cwL, a chemical solution of a prescribed concentration (4000.2000 ppm in this case) prepared by diluting an emulsion of each test compound with water is added to 100% of the weed.
It was sprayed on the stems and leaves of weeds using a small sprayer at a rate of 1/10a. Three weeks later, the growth status of weeds was investigated.

The investigation method was conducted by inspection according to the basic method shown below.
The results shown in the table were obtained.

Damage rate 0:0 2: 20-301 4: 40-50 6: 60-70 N 8: 85-95 N 10: 100 #Also 1,
The display of 3.5.7.9 is 0, 2.2, 4.4 and 6.9 respectively.
It shows a value between 6, 8.8 and 10.

Second Table of Contents Control Compound 1: Control Compound 2: Test Example 2 Crop Phytotoxicity Test A 100 d pot was filled with soil. When the crop has grown to the 1st to 3rd leaf stage, a chemical solution of a predetermined concentration (4000 ppm and 2000 ppm in this case) prepared by diluting the emulsion of each test compound with water is added to
It was sprayed on the foliage of crops at a rate of 10a using a small sprayer. Three weeks later, the growth status of the crops was investigated. The growth condition was investigated according to the same criteria as Test Example 1, and the results shown in Table 3 were obtained.

Table 3 Rice Control Compound 1: Same as Test Example 1 Test Example 3 Paddy soil was placed in a 100 d hot pot, and seeds of Japanese cypress, Japanese cypress, firefly, and Omodaka were sown, and seedlings of Japanese pine were transplanted. After 18 days, rice plants at the 3rd to 4th leaf stage were transplanted, and on the next day, the water depth was maintained at 3 sieves, and the granules of the test compound formulated according to the formulation of Formulation Example 3 were treated with an equivalent amount of 100g/10a. Three weeks later, the growth status of rice and weeds was investigated, and the results are shown in Table 4. The investigation criteria were the same as in Test Example 1.

Applicant: Nippon Soda Co., Ltd. Agent: Haruyuki Ito: Yoshimi Yokoyama 23- Procedural amendment September 1981, G-day Patent Office Commissioner Kazuo Wakasugi 1, Display of the case 1982 Patent Application No. 102983 2, Name of the invention: Pyridazine derivative and selective herbicide 3, Relationship to the amended person's case Patent applicant (430) Takeo Sannomiya, representative of Nippon Kodatsu Co., Ltd. 4, agent of Nippon Soda Internal phone number (245) 6234 (1) Specification Detailed description of the invention column 6, contents of amendment (1) Changed 10 lines from the bottom of page 7 of the specification “Production example” to “
Please cite a production example.''

(2) In the fourth line from the bottom of page 7 of the specification, ``Kendaku'' is corrected to ``1 Suspension''.

(3) "Ethyl methyl" in the fourth line from the bottom of page 7 of the specification is corrected to "ethyl methyl."

(4) In the specification, page 8, line 10, page 9, line 5, and page 9, line 4 from the bottom, ``kendaku'' is corrected to ``1 suspension''.

(5) In the bottom line of page 9 of the specification, "Roromethyl methyl sulfide" is corrected to "10 lomethyl methyl sulfide."

(6) Delete "Compound No. 15" on page 12 of the specification.

(7) "Alopex" on page 15, line 12 of the specification is corrected to "Alopex".

(8) Reference compound on page 20 of the specification ■ 1- (9) Reference compound on page 23 of the specification ■ ``Same as Test Example 1'' [ 3- Procedural amendment (method) November 10, 1982 Relationship between Patent Application No. 102983 No. 3 of 1982 and the amended case Patent applicant ◎ 100 2-2-1 Otemachi, Chiyoda-ku, Tokyo (430
) Nippon Soda Co., Ltd. Representative: Takeo Sannomiya 4, Agent ■ 100 2-2-1 Otemachi, Chiyoda-ku, Tokyo Nippon Soda Co., Ltd. Telephone: (245) 6234 November 10, 1980 (Shipping date) 6. Amendment Subject of September 140, 1982 Procedural Amendments Contents of the 74th Amendment As shown in Attachment 2 - Procedural Amendment September 14, 1980 Commissioner of the Japan Patent Office Mr. Wainu Wakasugi 1, Indication of the Case 1988 Patent Application No. 102983 No. 2, Name of the invention Pyridazine derivatives and selective herbicides 3. Relationship with the person making the amendment Patent applicant ■ 100 2-2-1 Otemachi, Chiyoda-ku, Tokyo (430
) Kuchimoto Soda Co., Ltd. Representative: Niio Sannomiya 4, Agent ■ 100 Nippon Soda Co., Ltd., 2-2-1 Otemachi, Chiyoda-ku, Tokyo, Japan Specification Column for detailed description of the invention

Claims (1)

[Scope of Claims] 1. General formula [wherein R3 is a chlorine atom or 0R3 (R, is a lower alkyl group substituted with a lower alkylthio group or a di-lower alkylamino group, a lower alkoxycarbonylamino group, a benzoylamino group, Di-lower alkylamino group, benzenesulfonyl group with or without substituents, or formula C
represents an amide group represented by ON<' (in the formula, r+2 represents a lower alkyl group, and r2 represents a lower alkyl group or a lower alkoxy group). )
R2 is an organic group represented by the formula 0N=C<' (in the formula r
3 represents a lower alkyl group, and r4 represents a lower alkyl group or phenyl group which may be substituted with a lower quaternary alkylthio group. ) or a hydrogen atom. However, when R1 is a chlorine atom, R2 is not a hydrogen atom. ] A compound represented by (In the formula, r4 represents a phenyl group, a lower alkyl group, or a lower alkylthio lower alkyl group.) 3. General formula (in the formula, R8 is a lower alkyl group substituted with a lower alkylthio group or a di-lower alkylamino group, a di-lower alkylamino group, a lower alkoxycarbonylamino group, a benzoylamino group, or has a substituent, or Claims represented by the following formula: a benzenesulfonyl group, or an amide group represented by the formula CON Compound according to item 1. 4. General formula [wherein R1 is a chlorine atom or 0R8 (R, is a lower alkyl group substituted with a lower alkylthio group or a di-lower alkylamino group, a lower alkoxycarbonylamino group, a benzoylamino group] , di-lower alkylamino group, benzenesulfonyl group with or without substituents, or formula C
It represents an amide group represented by ON<1 (in the formula, rI2 represents a lower alkyl group, and r2 represents a lower alkyl group or a lower alkoxy group). )
R2 is an organic group represented by the formula 0N=C< (in the formula, r represents a lower alkyl group, and r4 represents a lower alkyl group or phenyl group which may be substituted with a lower 4-alkylthio group). Indicates a group or a hydrogen atom. However, when R is a chlorine atom, R2 is not a hydrogen atom. ] A selective herbicide characterized by containing a compound represented by the following as an active ingredient.