JPS5929669A - Aminopyrazole derivative - Google Patents

Abstract

NEW MATERIAL:The 5(3)-amino-3(5)-tertiary-butylpyrazole of formula I and formula II. USE:An intermediate of an amide compound, carbamate compound or urea compound useful as a herbicide. PROCESS:The compound of formula I or formula II can be prepared easily by reacting cyanopinacolin of formula III with hydrazine of formula IV in a proper solvent preferably under heating at 30-100 deg.C. When the obtained compound is made to react with carboxylic acid halide, haloformate, or carbamoyl halide, an amide compound, carbamate compound or urea compound can be obtained, respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a novel compound, 5(3)-amino-3(5).
-Tertiary-butylpyrazole (hereinafter abbreviated as ABP).

ABP has two types of tautomers, each represented by the following structural formula.

σ) 0 The ABP of the present invention is a new compound that has not been described in literature, patents, etc., but is a useful compound as an intermediate for the synthesis of agricultural chemicals, etc. For example, it can be combined with carboxylic acid nolide, haloformate, carbamoyl halide, etc. By reacting, an amide compound, a carbamate compound, or a urea compound can be obtained, respectively. Some of these compounds have excellent efficacy as herbicides. Incidentally, as homologs of the compounds of the present invention, compounds in which the t-butyl group of the pyrazole ring is a methyl group, 1so-propyl group, 5eC-butyl group, or phenyl group are known (Chemical Abstracts, Vol. 83). , 43233J), when the amide compound and carbamate compound having herbicidal activity derived from the aminopyrazole having a t-butyl group of the present invention are compared with the compound having the same structure derived from the above-mentioned homologues, the following reference is made. As is clear from the examples, there are extremely significant differences in their herbicidal activity.

The compound of the present invention can be easily synthesized by a method in which cyanobinacholine and hydrazine are heated and reacted in an appropriate solvent.

CH3 [CH2O-COCH2CN+H2NNH2->ABPC
H3 Solvents in this reaction include alcohols such as methanol, ethanol, and impropatol, aromatic hydrocarbons such as benzene, toluene, and xylene, and halogenated hydrocarbons such as carbon tetrachloride, chloroform, and methylene chloride. The reaction temperature is preferably 30 to 100°C.

The method for synthesizing the compound of the present invention will be explained below in more detail by showing representative examples. However, it goes without saying that this is just an example and is not limiting in any way.

Synthesis Example 94 g of cyanobinacholine was dissolved in 300% of ethanol, 509% of hydrazine hydrate was added thereto, and the mixture was heated at 70 to 80°C.
The reaction was carried out at a temperature of 2 hours. After distilling off the reactant ethanol, 300 ml of methine chloride was added and transferred to a separating funnel, and an appropriate amount of water was added and shaken to remove unreacted hydrazine by washing with water. The remaining organic phase was dehydrated with Glauber's salt, the solvent was distilled off, and the mixture was allowed to stand at room temperature to gradually crystallize, yielding 98 g of ABP. Purification was performed by recrystallization using benzene as a solvent.

Melting point near 8-79℃ (uncorrected) Elemental analysis (calculated values in parentheses): C: 60.15 (60,
40), H: 9.63 (9,41), N: 30
．． 29 (30,19) (section) Mass spectrum: m
/z 139.124.97°84, Infrared absorption spectrum (KBr tablet) = 3370.3340.3200
．． 2960,1600.1500゜1490.800.
715 (cIn-') Main peak only Ultraviolet absorption spectrum (methanol solvent) Two people maX 223 m Nuclear magnetic resonance spectrum (deuterated chloroform solvent, reference material tetramethylsilane, 60 MHz): 1.24 (S
, 9H), 5.42 (s, IH)% 5.5-6
．． 2 (br, 3H) An amide compound and a carbamate compound having herbicidal activity can be synthesized from the compound of the present invention according to the following methods.

(Method of synthesizing an amide compound) Aminopyrazole is dissolved in a solvent, and an acid halide or an acid anhydride is added dropwise thereto to react.

Although the reaction proceeds even in the absence of a base, an inorganic or organic base may be present in order to carry out the reaction under milder conditions.

Examples of solvents include aromatic hydrocarbons such as benzene, toluene and xylene, halogenated hydrocarbons such as carbon tetrachloride chloroform and methylene chloride, cyclic ethers such as THF and dioxane, ketones such as acetone MEK, and esters such as ethyl acetate. , nitriles such as acetonitrile, etc. Bases include alkali metal carbonates, alkali metal bicarbonates, tertiary amine pyridine, etc. The molar ratio of acid halide or acid anhydride to aminopyrazole is 1.0 to 1. 2
The appropriate reaction temperature is about 0 to 150°C.

(Synthesis Example) 90 g of 5(3)-tert-butyl-3(5)-Viva Misakiylaminopyrazole ABP is dissolved in 200 g of benzene, and 80 g of piparoyl chloride is added dropwise. After heating under reflux for 3 hours,
The reaction solution was added to an aqueous sodium carbonate solution with stirring to crystallize, filtered, washed and dried to obtain 116 g of 5(3)-tert-butyl-3(5)-pivaloylaminopyrazole.

(Synthesis method of carbamate compound) Aminopyrazole is dissolved in a solvent, chloroformic acid ester is added dropwise, and then a heating reaction is carried out. Suitable solvents include aromatic hydrocarbons such as benzene, toluene, and xyleno, halogenated hydrocarbons such as carbon tetrachloride, methylene chloride, and chloroform, and cyclic ethers such as tetrahydro-xrane and dioxane.
The temperature is preferably about 150°C.

(Synthesis example) 10 g of methyl-N-(5(31-tert-butyl-3(5)-pyrazolyl)carbamate ABP was dissolved in 100 g of carbon tetrachloride, and 648 g of methyl chloroformate was dissolved in 100 g of carbon tetrachloride.
After adding g, the mixture is heated under reflux and reacted for 5 hours. After cooling, add an aqueous potassium carbonate solution to form crystals. This was passed through the mouth, washed with water and carbon tetrachloride, and 3.8 g of methyl-N
-[5(3)-tert-butyl-3(5)-pyrazolyl]carbamate was obtained.

In order to demonstrate the herbicidal effects of the above-mentioned compounds derived from the compounds of the present invention, as well as amide compounds and carbame-1 compounds having similar structures, some representative test examples will be given and explained in more detail.

Test example 1 Herbicidal effect on plants when pre-emergent soil treatment.

A pot with an area of 100 r and nl was filled with volcanic ash soil and planted with Digitaria sanguinalis.
), Echinochloa crus-g
Po-1ygonum n.
odosum), Amarantbusr (Amarantbusr)
etroflexus), corn (Zeama
yS), wheat (Triticum aestivum)
), Yaenari (Phase-olus radiat
Sow 1 seed of U.S.) and cover with soil to a depth of about 5 m. Immediately after that, prepare an irrigation agent using the compounds listed in Table 1 according to Example 1, dilute it with water, and add the active ingredients. A dose corresponding to D 2.5 Ks+ per hectare was applied to the soil surface of each pot. The herbicidal effect on plants was adjusted 2 weeks after treatment. Weeding effect was visually observed: O: No effect ~ 5
: Shown in the table as an index of complete withering stage 06.

Test example 2 Herbicidal effect on plants when treated with foliage contact treatment.

Fill a pot with a surface area of 100 cJ with volcanic ash soil and plant Digitaria sanguinalis.
, Echinochloa crus-ga
Polygonum no.
dosum), Amaran-thus
retroflexus), corn (Zeam
ays) Wheat (Triticum aestivum)
), pHa-seolus radiat
Seeds of the following species are sown, covered with about 1 ounce of soil, placed in a greenhouse, and when the weeds have one or two leaves, an irrigation agent of the compound of the present invention is applied at a dose equivalent to 925:9 per hectare. 1
00OA! The solution was diluted with water equivalent to /lla 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 the table.

Test Example 3 Herbicidal effect on paddy field weeds and phytotoxicity test on paddy rice A pot with a surface area of 120 cy+f was filled with paddy soil, and Echinochloa crus-gal
li), Monochoria vagina
The seeds of Eleocharis acicularis were soaked into the soil to a depth of approximately 2 c1n, and the seeds of Eleocharis acicularis
) and paddy rice fungi at the two-leaf stage were transplanted to two locations each, and the water depth was maintained at approximately 311,771 cm. After 3 days, an irrigation agent containing the compound of the present invention prepared according to Example 1 was added per hectare.
A dose corresponding to 2.5 Kg was administered in water.

Three weeks after 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 was expressed using a 6-level index. The test results are shown in the table.

Compound Ni CB (CH2CI-I3D CH3 Ni C61-I5E R' Ni C (CH3), F As is clear from these results, the t-butyl group of the pyrazolyl ring of the pyrazolylamide compound and the pyrazolyl carbamate compound having herbicidal activity was methylated. Compounds in which a substituent similar to a group, 1so-propyl group, or 5ec-butyl group is substituted have almost no herbicidal activity or become very weak.

Patent applicant: Showa Denko Co., Ltd. Agent Sei Kikuchi

Claims (1)

[Claims] 5(3)-Amino-3(5)-noshaributylpyrazole.