Substituted pyrazolylpyrazole derivative and use of same as herbicide

Abstract

Provided is a compound capable of effectively control worst weeds of higher leaf stages that present practical problems. A specific pyrazolylpyrazole derivative of formula (I) is disclosed that is able to solve the above-mentioned problems. ##STR00001##

Claims

1. A compound represented by the following formula (I): ##STR00006## wherein, R.sup.1represents a halogen atom, R.sup.2represents a cyano group or nitro group, R.sup.3represents a hydrogen atom, halogen atom, C.sub.1-C.sub.6 alkyl group which may be substituted with one or more halogen atoms, or C.sub.1-C.sub.6 alkoxy-C.sub.1-C.sub.6-alkyl group, a represents 3 to 5, and b represents 1 to 3.

2. An herbicide composition comprising an herbicidally effective amount of at least one compound according to claim 1.

3. The herbicide composition according to claim 2, further comprising a formulation assistant.

4. A method for control of undesirable plants, comprising applying an effective amount of at least one compound according to claim 1 to an undesirable plant or a location of the undesirable plants.

5. The method according to claim 4, wherein the at least one compound is applied to the undesirable plants among useful agricultural crops.

6. A method for control of undesirable plants, comprising applying an effective amount of the herbicide composition according to claim 2 to an undesirable plant or a location of the undesirable plants.

7. The method according to claim 6, wherein the herbicide composition is applied to the undesirable plants among useful agricultural crops.

8. A method for control of undesirable plants, comprising applying an effective amount of the herbicide composition according to claim 3 to an undesirable plant or a location of the undesirable plants.

9. The method according to claim 8, wherein the herbicide composition is applied to the undesirable plants among useful agricultural crops.

Description

EXAMPLES

Example 1

Method for the Synthesis of 1-(3-chloro-4,5,6,7-tetrahydropyrazolo[1,5-a]pyridin-2-yl)-5-(but-3-ynylamino)pyrazole-4-carbonitrile (Compound 1)

(1) Formic acid (18.4 g) was slowly dropped into acetic anhydride (33.7 g) cooled to 5 C. followed by stirring for 2 hours at 60 C. (Reaction Mixture A). Separate from the above, 5-amino-1-(3-chloro-4,5,6,7-tetrahydropyrazolo[1,5-a]pyridin-2-yl)pyrazole-4-carbonitrile (26.3 g) was dissolved in acetonitrile (200 ml) and stirred. The previously prepared Reaction Mixute A was slowly dropped therein and reacted for 1 day at room temperature and then for 4 hours at 60 C. The solvent was concentrated under reduced pressure followed by neutralizing using aqueous potassium carbonate solution, washing the precipitated solid with water and drying to obtain N-(1-(3-chloro-4,5,6,7-tetrahydropyrazolo[1,5-a]pyridin-2-yl)-4-cyanopyrazol-5-yl)formamide (28 g).

(2) N-(1-(3-chloro-4,5,6,7-tetrahydropyrazolo[1,5-a]pyridin-2-yl)-4-cyanopyrazol-5-yl)formamide (50 g) was dissolved in acetonitrile (300 ml) followed by adding potassium carbonate (29 g) and stirring. 4-bromo-1-butyne (27.4 g) was added thereto followed by refluxing for 3 days. Following completion of the reaction, water was added followed by extraction with ethyl acetate. After drying with sodium sulfate, the solvent was concentrated under reduced pressure and the resulting crude product was purified by silica gel column chromatography (hexane/ethyl acetate=1:1) to obtain N-(but-3-ynyl)-N-(1-(3-chloro-4,5,6,7-tetrahydropyrazolo[1,5-a]pyridin-2-yl)-4-cyanopyrazol-5-yl)formamide (20 g).

(3) N-(but-3-ynyl)-N-(1-(3-chloro-4,5,6,7-tetrahydropyrazolo[1,5-a]pryidin-2-yl)-4-cyanopyrazol-5-yl)formamide (20 g) was dissolved in ethanol (150 ml) followed by the addition of 10% hydrochloric acid (8.8 g) and refluxing for 1 day. Following completion of the reaction, water was added to the reaction liquid and the precipitated solid was filtered out to obtain the desired compound (15 g).

(4) The starting material in the form of the compound of formula (II) was synthesized in accordance with WO 93/10100 and WO 94/08999.

(5) The examples listed in the following tables can be synthesized by the same manner as the above-mentioned methods or obtained in the same manner as the above-mentioned methods.

(6) TABLE-US-00001 TABLE 1 (I) Compound R.sup.1 R.sup.2 R.sup.3 a b mp Refractive index ( C.) 1 Cl CN H 4 1 130-131 2 Cl CN H 3 1 3 Cl CN H 5 1 4 Cl CN Me 4 1 5 Br CN H 4 1 6 Br CN H 3 1 7 Cl NO.sub.2 H 4 1 8 Br NO.sub.2 H 4 1
<Preparation Examples>

(7) TABLE-US-00002 1. Dustable powder Compound of formula (I) 10 parts by weight Talc 90 parts by weight A dustable powder is obtained by mixing the above components and finely crushing with a hammer mill. 2. Wettable Powder Compound of formula (I) 10 parts by weight Polyoxyethylene alkyl aryl ether sulfate 22.5 parts by weight White carbon 67.5 parts by weight A wettable powder is obtained by mixing the above components and finely crushing the mixture with a hammer mill. 3. Plowable concentrate Compound of formula (I) 10 parts by weight Polyoxyethylene alkyl ether phosphate 10 parts by weight Bentonite 5 parts by weight Ethylene glycol 5 parts by weight Water 70 parts by weight A flowable concentrate is obtained by mixing the above components and crushing using a wet pulverizer. 4. Emulsifiable concentrate Compound of formula (I) 15 parts by weight Ethoxylated nonylphenol 10 parts by weight Cyclohexanone 75 parts by weight An emusifiable concentrate is obtained by mixing the above components. 5. Granules Compound of formula (I) 5 parts by weight Calcium lignin sulfonate 3 parts by weight Polycarboxylate 3 parts by weight Calcium carbonate 89 parts by weight The above components are mixed followed by adding water, kneading, extruding and granulating. Subsequently, granules are obtained by drying followed by sizing.
<Biological Testing Examples>

(8) 1. Paddy Herbicidal Activity Test

(9) Rice paddy soil was filled into a 1/10000 are pot followed by the addition of suitable amounts of water and chemical fertilizer, kneading, seeding with Echinochloa crus-galli, Monochoria vaginalis and Scirpus juncoides and maintaining in an irrigated state at a water depth of 3 cm.

(10) Wettable powder of Target Compound (I) shown in Table 1 prepared in compliance with the preparation examples were diluted with a suitable amount of water, rice plants in the 2.0 leaf stage were transplanted during 3.5 leaf stage of Echinochloa crus-galli, and treated by dropping in chemical in the prescribed amount per are using a pipette.

(11) After treating for 30 days in a glass greenhouse at an average atmospheric temperature of 30 C., the herbicidal efficacy thereof was investigated.

(12) Evaluation of herbicidal efficacy was carried out by comparing growth inhibition rate (%) with an untreated group, while evaluation of phytotoxicity was carried out by comparing growth inhibition rate (%) with the state of a complete eradication group, and were evaluated at 11 levels indicated below.

(13) 0 (exponent): 0% to less than 10% (growth inhibition rate)

(14) 1: 10% to less than 20%

(15) 2: 20% to less than 30%

(16) 3: 30% to less than 40%

(17) 4: 40% to less than 50%

(18) 5: 50% to less than 60%

(19) 6: 60% to less than 70%

(20) 7: 70% to less than 80%

(21) 8: 80% to less than 90%

(22) 9: 90% to less than 100%

(23) 10: 100%

(24) The results are shown in Table 2.

(25) ##STR00005##

(26) TABLE-US-00003 TABLE 2 5 g.sup.a.i./10 a 1 g.sup.a.i./10 a Echinochloa Scirpus Monochoria Rice Echinochloa Scirpus Monochoria Rice Compound crus-galli juncoides vaginalis plants crus-galli juncoides vaginalis plants 1 10 10 10 1 9 8 9 0 4.73 4 1 4 1 2 0 3 0 4.85, 4.156 3 1 3 2 2 0 1 2 4.131, 4.132 4 3 1 1 3 1 0 1

(27) 2. Farming Soil Treatment Test

(28) Field soil was filled into a 1/6000 are pot followed by seeding with Digitaria ciliaris, Chenopodium album and Amaranthus retroflexus and covering with soil.

(29) Wettable powder of Target Compound (I) shown in Table 1 prepared in compliance with the preparation examples were diluted with water to the prescribed amount of chemical and uniformly sprayed onto each soil surface layer using 10 liters of sprayed water per are prior to weed growth following seeding.

(30) After treating for 30 days in a glass greenhouse at an average atmospheric temperature of 30 C., the herbicidal efficacy thereof was investigated.

(31) Evaluation of herbicidal efficacy was carried out in the same manner as the above-mentioned Test Example 1.

(32) The results are shown in Table 3.

(33) TABLE-US-00004 TABLE 3 10 g.sup.a.i./10 a 5 g.sup.a.i./10 a Digitaria Chenopodium Amaranthus Digitaria Chenopodium Amaranthus Compound ciliaris album retroflexus ciliaris album retroflexus 1 10 10 10 10 10 10 4.73 1 2 2 0 1 1 4.85, 4.156 4 5 6 3 4 3 4.131, 4.132 4 4 5 3 3 4

(34) 3. Weed Foliar Treatment Test

(35) Soil was filled into a 1/6000 are pot followed by seeding with Digitaria ciliaris, Chenopodium album and Amaranthus retroflexus, covering with soil, and cultivating in a glass greenhouse at an average atmospheric temperature of 25 C.

(36) Wettable powder of Target Compound (I) shown in Table 1 prepared in compliance with the preparation examples were diluted with water to the prescribed amount of chemical and uniformly sprayed onto the weeds using 15 liters of sprayed water per are when Digitaria ciliaris had grown to the 1.0 to 2.0 leaf stage.

(37) After treating for 3 weeks in a glass greenhouse at an average atmospheric temperature of 25 C., the herbicidal efficacy thereof was investigated.

(38) Evaluation of herbicidal efficacy was carried out in the same manner as the above-mentioned Test Example 1.

(39) The results are shown in Table 4.

(40) TABLE-US-00005 TABLE 4 10 g.sup.a.i./10 a 5 g.sup.a.i./10 a Digitaria Chenopodium Amaranthus Digitaria Chenopodium Amaranthus Compound ciliaris album retroflexus ciliaris album retroflexus 1 10 10 10 10 10 10 4.73 2 3 3 1 2 3 4.85, 4.156 5 6 6 3 5 4 4.131, 4.132 4 5 6 3 4 4

INDUSTRIAL APPLICABILITY

(41) According to the present invention, the compound for formula (I) of the present invention is useful as a herbicide against harmful plants since it has superior herbicidal efficacy against undesirable plants.