JPS5896071A - Pyrazole derivative, its preparation and herbicide - Google Patents

Abstract

NEW MATERIAL:The pyrazole derivative of formulaI(R is H, lower alkyl, lower haloalkyl, or lower alkenyl; R' is lower alkyl, lower alkenyl, phenyl, or phenyl substituted with alkyl, alkoxy, halogen, etc.; X is O or S). EXAMPLE:3-tert-Butyl-1-phenylcarbamoyl-5-propionylaminopyrazole. USE:A herbicide having strong herbicidal activity to a wide variety of weeds, and exhibits especially high killing effect just before the sprouting of weeds or at the initial stage of the growth. It is useful for the selective control of weeds in the field growing corn, potato, sugar cane, peanuts, etc. PROCESS:The compound of formulaIcan be prepared by reacting the compound of formula II with the compound of formula III (R' is lower alkyl, lower alkenyl, etc.) in an organic solvent such as benzene, at 0-100 deg.C, preferably using a base as a catalyst.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is based on the general formula I represents an oxygen atom or a sulfur atom), a method for producing the same, and a herbicide containing the compound as an active ingredient.

The compound of the present invention is characterized by having a tert-butyl group at the 3-position of the pyrazole ring, which is of great significance in terms of herbicidal activity. Furthermore, by introducing a carbamoyl or thiocarbamoyl group at the 1-position, the herbicidal activity, especially in foliage treatment, is increased compared to the case without substitution.

The compound of general formula 1 exhibits strong herbicidal activity against a wide range of weeds, and the active ingredient is applied at a rate of 0.5 to 100% per hectare just before the weeds germinate or at an early stage of their growth.
To! When applied, it can kill a wide range of weeds as described below within about 2 to 3 weeks.

In addition, by limiting the amount of this compound applied or applying a suitable application method, it is possible to Weeds can be selectively controlled in fields where crops are grown.

Typical examples of the compounds of the present invention include those shown in Table 1.

The compounds in the table are numbered, and the following description will be indicated using the compound number.

The melting point values in the table are uncorrected, and the NMR values are 60
Measured at megahertz using tetramethylsilane in deuterated chloroform as a substrate substance, with the symbols s, d, t, q,
m indicates a peak pattern of 1.2.3.4 and a multiplet, ar indicates a peak due to aromatic H, and br indicates a wide peak pattern, and J indicates a spin coupling constant.

(The following is a blank space) The compound of the present invention can be produced, for example, according to the following reaction formula. (In the formula, R1R' and X are as described above).

This anti-i 1d A regular Hensen, toluene, xylene carbon tetrachloride, chloroform, methylene salt, dioxane,
It is carried out at a temperature of about 0 to 120°C using acetonitrile or optionally without a solvent. The reaction can be accelerated by adding a base such as pyridine or triethylamine as a catalyst.

Compound 1 produced by the above reaction is generally poorly soluble in water, but it can be used in alcohols, acetone, benzene, toluene, etc.
Carbon tetrachloride, chloroform, etc. dissolve well in most organic solvents. It is also soluble in hydrocarbon solvents such as hexane.

Next, synthesis examples will be shown for reference, and the method for producing the active compound of the present invention will be specifically described.

Example 1 4 g of 3-tertiary-butyl-5-propionyl minopyrazole is reacted with 50 ml of dioxane (added F and 2.6.9 ml of phenyl isocyanate) at 0°C for 3 hours.The reaction solution is concentrated and crystallized. and washed with hexane to give 59!q of 3-tert-butyl-1-phenylcarbamoyl-5-propionylaminopyrazole (
Compound 9) was obtained. Compound identification was performed by infrared and NMR. The position of the substituent on the nitrogen of the pyrazole nucleus was determined by C-13 MR and X-ray analysis.

Example 2 In Example 1, instead of phenyl isocyanate, 1.6 g of methylisothiocyanate was used and heated under reflux for 5 hours. The reaction solution was concentrated and crystallized to obtain 15 g of 3-tert-butyl-1-methylthiocarbamoyl-5-propionylaminopyrazole (1.4).

Example 3 2.9 of 5-acetylamino-3-tert-butylpyrazole was added to 30 ml of dioxane and reacted with 07 g of ethyl isocyanate at room temperature for 24 hours. After distilling off the solvent, hexane was added and insoluble materials were removed, concentrated and crystallized. .39
5-acetylamino-3-tert-butyl-1-methylcarbamoylpyrazole (1) was obtained.

Example 4 4 g of 3-tert-butyl-5-pivaloylaminopyrazole was added to 50 m/! of carbon tetrachloride! In addition to 11! Heat Ra for 5 hours with methyl isocyanate. After the reaction, it was concentrated and crystallized to give 42 g of 3-tertiarybutyl-1-methylcarbamoyl-5-pivaloylaminopyrazole (1
7) Woil.

Example 5 2 g of 3-tert-butyl-5-methacryloylaminopyrazole was added to 30 ml of benzene, and 14 g of m-
) 'J Lef and heat under reflux with ananate for 5 hours. After the reaction, the solvent was distilled off, hexane was added, insoluble matter was filtered out, and the residue was concentrated and crystallized to obtain 151/3-tert-butyl-5-methacryloylamino-1-(m-methylphenylcarbamoyl)pyrazole (28).

Although some examples have been given above, other compounds can also be produced by similar methods.

The active compounds according to the invention can be formulated into dosage forms such as emulsions, wettable powders, pastes, floatables, powders, and granules by applying conventional formulation methods.

Furthermore, the compounds of the present invention can be mixed with other herbicides, and in order to expand the range of action, they can be mixed with agricultural chemicals other than herbicides, such as insecticides, nematicides, and fungicides. can.

Next, examples of typical dosage forms will be given. "Department" in the description
indicates parts by weight.

Example 1 Wettable powder active ingredients: 50 parts of the compounds shown in Table 1, 10 parts of diatomaceous earth, 35 parts of clay, 3 parts of sodium polyoxyethylene alkyl acrylic ether sulfonate, and 2 parts of sorta argylnaphthalene sulfonic acid. are mixed and pulverized to obtain a wettable powder containing 50% of the active ingredient compound.

When using, dilute with water to the specified concentration and spray.

Example 2 Granules 5 parts of the compound shown in Table 1, 20 parts of bentonite, 73 parts of clay and 2 parts of sodium dodecylbenzenesulfonate were mixed,
After adding 20 parts of Honsuri and kneading with a mixer, the mixture is granulated through a granulator, and then dried and sized to obtain granules containing 5% of the active ingredient.

Example 3 Emulsion 50 parts of the compound shown in Table 1 as an active ingredient, 45 parts of cysilene, and 5 parts of polyoxyethylene alkyl allyl ether are mixed to form a homogeneous solution to obtain an emulsion containing 50% of the active ingredient. . When using, dilute with water to the specified concentration and spray.

The novel pyrazole derivatives of general formula I have excellent herbicidal activity and are therefore suitable for controlling weeds that grow in fields, orchards, non-agricultural lands, etc. When this active compound is applied to the soil surface or mixed into the soil, it can significantly inhibit the growth of weeds and cause them to die. Weeds can also be controlled by spraying the main agent on the leaves and stems of weeds that are only growing.

The dosage of this compound is regulated to reduce the application amount to 0 per hectare.
5 to 51 (g), it can be used as a selective herbicide in cultivated fields of corn, wheat, barley, humpback, soybeans, peanuts, sunflowers, potatoes, cotton, fruit trees, etc. Also, when the application amount is increased It can be applied as a non-selective herbicide.

The compounds of the present invention can be used, for example, to control the following weeds: That is, dicotyledonous plants, such as chickweed (5tellaria media), whitebacus (
ChenopodillTIajbum), Sagjma jap-onica, Koakaza (Sagjma jap-onica),
Chonopodium ficifoliurn)
, Poiygonum nodosum
), Portulaca olerac
ea ), shepherd's purse (Capsella bursa-p
astroris), Lepidiu
m virgini-cum), canine cum (Por
ippa 1ndjca), Tanetsukebana (Car
damine Hexuosa), Ichibi (Abut
ilonav-icennae), American silver deer (5ida 5pinosa) Malva → Nogao (I
pomoea purporea), wildflower (pomoea purporea)
5enecio vulgaris), Japanese poppy (
5onchus asp-er), 13idens frondosa (13idens frondosa), pigweed (13idens frondosa),
Ambrosia artemisiaefolia
) Lamium am piexicavle (A3j6rBubulatus), Lamium am piexicavle
), Oxalis cornicolate
), Ama?anthus retro
flcxus), Vicia 5
ativa), Yaemugura (Galium spur)
i-um), Solanum nig
rum), Datura st.
ramonium), grass family plants such as Poa annua, Alopeculus aequaljs, Digitaria adsendsns,
Eleusine 1n-dica, Eleusine viridis (5etaria viridis),
Golden millet (Echinochioa krug ga mouth 1), A-gropyrontsukus
hiensis), Bokmugi (Lolium per
-enne), dogwheat (Bromus catha)
rticos), oat (Avena tat)
ua ), Po lypogon Hi
-ge gawe r i), Pan
icum dichotomif-1orom),
Cyperus weeds, such as Cyperus japonica (Qyper)
us m1croiria), Cyperus japonica (Cy
-perus Ir1a), Carex
rugata) etc.

The compounds of the present invention have excellent herbicidal efficacy against a wide range of weeds as described above, and are particularly effective when applied to the surface of fields or the foliage of plants just before or after weeds germinate. High pest control effect can be obtained.

Also, when the compound of the present invention is mixed into soil, an extremely excellent weed control effect can be obtained.

In order to demonstrate the herbicidal effect of the herbicide according to the present invention, some representative test examples will be given and explained in more detail.

Test Example 1 Pre-emergence soil treatment (pre-emergence 5oi
Herbicidal effect area on plants when using 1. Fill the OOcm2 bot with volcanic ash soil and grow the
), Golden millet (Ec-hinochlon crus
galli), Polygon-um
nodosum), Aobi-7- (Amarant
hus retrof-1exus), 1ゝ corn (Zea mays), wheat (Tritjcu)
Seeds of Phaseoidus radiotus (Phaseoidus radiotus) were sown, covered with soil to a thickness of about 51 nm, and immediately after that, compounds listed in Table 1 were prepared as an irrigation agent according to Example 1, Dilute this with water and the active ingredient will be 10 kg per hectare.
was applied to the soil surface of each bot. Two weeks after treatment, the herbicidal effect on plants was investigated. The herbicidal effect was visually observed and expressed in Table 2 on a 6-level index from 0: no effect to 5: complete death.

Test Example 2 Leaf contact treatment (Foliar 5play trea
trnent) Herbicidal effect of mowing plants in the case of volcanic ash soil in a pot with a surface area of 100C1n2,
), Echinochloa crusg
Po-1ygonum), Po-1ygonum
nodosum), Amaranthus
re-Lroflexus), corn (Ze
a mays) Wheat (Triticum aest)
ivum), Yaenari (Phaseolusradii)
Atus) seeds are sown, covered with soil of approximately]c7n, placed in a greenhouse, and when the weeds have 1 to 2 leaves, an irrigation agent of the compound of the present invention is applied at a dose of 10 per hectare, equivalent to y. was diluted with water equivalent to 100,017 ha and sprayed using a sprayer. Ten days after the chemical spraying, the test was conducted using the same criteria as in Test Example 1, and the results were expressed using a 6-level index. The test results are shown in Table 3.

Test Example 3 Herbicidal effect on paddy field weeds and phytotoxicity test on paddy rice A bot with a surface area of 120 Crn2 was filled with paddy soil, and it was used to infiltrate Echinochloa crusgalli and Monochoria vagjnalis.
seeds were mixed into the soil at a surface layer of about 2 crn, and
Hieocharis acicularis) and 2
Transplant paddy rice weeds in the leaf stage to two locations each, and raise the water depth to approximately 3.
Keep it at cm. Three days later, an aquarium containing the compound of the present invention prepared according to Example 1 was administered into the water in an amount equivalent to 10 kl per hectare.

Three weeks after the chemical treatment, the herbicidal effect and chemical damage to paddy rice were investigated. The herbicidal effect and the chemical damage to crops were determined by Test Example 1.
The survey was conducted using the same criteria as the above, and the results were expressed using an index of 1.6. The test results are shown in Table 4.

From Table 4, it can be seen that the compounds of the present invention are effective in killing weeds, which are important weeds in paddy fields, such as grasshoppers, Japanese grasshoppers, and Japanese grasshoppers. However, this group of compounds also affects paddy rice.

r 99 ) From the above results, it is clear that the compounds of the present invention exhibit strong herbicidal activity against a wide range of weeds, and can be applied as herbicides for various crops.

Patent applicant: Showa Denko Co., Ltd. Agent: Patent attorney Sei Kikuchi (t・)ノ

Claims (1)

[Scope of Claims] 1) General formula % (wherein R is a hydrogen atom, a lower argyl group, a lower haloalkyl group, or a lower altanyl group, and R' is a lower alkyl group, a lower alkenyl group, or a phenyl group) (wherein I'tl-1: hydrogen atom, lower alkyl group). , lower haloalkyl group or lower alkenyl group) and the phenyl group substituted by the general formula R'NCX (in the formula: A method for producing a pyrazole derivative represented by the general formula (wherein R, R', and X are as described above), characterized by reacting a compound represented by ) General formula (wherein R is a hydrogen atom, a lower alkyl group, a lower haloargyl group, or a lower alkenyl group, R' or a phenyl group substituted with an alkino-type alkyl group, etc., and X is oxygen A herbicide containing, as an active ingredient, a pyrazole derivative represented by (representing an atom or a sulfur atom).