JPH08176153A - Pyridine-2,3-dicarboxylic acid imide,method of preparing same,herbicide containing same and method of using same to control weed - Google Patents

Abstract

PURPOSE: To obtain the subject compound having an improved selectivity and weedkilling effect through reacting a specific pyridinedicarboxylic acid anhydride with amine in an inert organic solvent.

CONSTITUTION: This compound of formula I [R¹ is H, an 1-4C alkoxy, (substituted) 1-6C alkyl, (substituted)3-8C cycloalkyl, (substituted)3-6C alkenyl or (substituted)alkynyl; and R² to R⁴ are each H, a halogen, cyano, (substituted) 1-6C alkyl, (substituted)benzyl, (substituted)3-8C cycloalkyl or the like] is obtained by reacting (A) a pyridinedicarboxylic acid anhydride with (B) a primary amine of R₂N-R¹ e.g. at -20 to 120°C in an inert organic solvent (e.g. tetrachloroethane) and then subjecting the obtained pyridinedicarboxylic acid half amide of formula III to cyclization by a hydrolyzing agent (e.g. acetanhydride). It is pref. conducted in the component ratio A/B of (0.9 to 1) to (3 to 1) in a molar ratio of the material to the solvent of (0.2 to 2) to 1.

COPYRIGHT: (C)1996,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a novel pyridine-2,3-dicarboxylic acid imide and an agriculturally usable salt thereof, a method for producing the same, a novel intermediate product for producing the same, a method for producing the same, and these compounds. The present invention relates to a herbicide contained therein and a herbicidal method using these compounds.

[0002]

2. Description of the Related Art N-Substituted pyridinedicarboxylic acid imides and their derivatives are known, and in particular, N-cycloalkylenepyridinedicarboxylic acid imides and their derivatives are described as a soil fungicide in Japanese Patent Application Publication No. 128006. .

In US Pat. No. 3,539,568,
A process for the preparation of 2,3- and 3,4-pyridinedicarboxylic acid imides and a conversion to isomeric dicarboxylic acid amides which can be used as intermediate products for herbicidal pyrimidinediones is described.

3-Carboxypyridine-2-N- (aryl) -carboxylic acid amides and phthalamic acids having a plant growth controlling action are known from US Pat. No. 4,261,730.

In US Pat. No. 4,658,030, 3
-Carboxypyridine-2- (N-2-carbamide-3
A process for the preparation of herbicidal 2- (imidazolinyl-)-nicotinic acid based on -methyl-2-butyl) -carboxylic acid amide is disclosed.

A method for producing pyridine-2,3-dicarboximide by the cycloaddition method is described in Helv. Chim.
Acta 1988, 71, 486-493.

From Japanese Patent Application No. 57-085386, a substituted pyridine-2,3-dicarboxylic acid imide having an antitumor effect is disclosed, and Canadian Patent Application No. 117-1.
From 50849 publication, 6-amino-5-cyano-4-
Phenylpyridinecarboxylic acid amides are known.

Pyridine-2,3-having a herbicidal action
Dicarboxylic acid imide is disclosed in Japanese Patent Application No. 422456.
It is known from the publication.

Regarding the novel intermediate product, the following points are known. First, 5-chloropyridine-2,3-dicarboxylic acid imide is described in J. Med. Chem. 17.106
It is known from 5. Halogen-substituted anhydrides such as 5-halogen-pyridine-2,3-dicarboxylic anhydride, 5-
Chloro- or perfluoro-pyridine-2,3-dicarboxylic acid anhydride is described in Chemical, Abstract 84 Vol. 1
35440 and 55, 23525 and Chem. B
er. 56 . It is known from 2457. Specific examples of pyridine-2,3-dicarboxylic acid esters and chlorides are Chemicals, Abstracts, Vol. 206, 213955, Nishi Unique Application Publication No. 3634975, European Patent Application Publication 2
It is known from JP-A-27932 and JP-A-299362.

[0010]

SUMMARY OF THE INVENTION It is therefore an object of this technical field or the object of the present invention to provide pyridine-2,3-dicarboxylic acids having an improved biological effect, in particular an improved selectivity and a high herbicidal effect. Find acid imide,
Is to provide.

[0011]

However, the object or object of the present invention is to solve the problems by the following general formula (I).

[0012]

[Chemical 16]And R¹ Is hydrogen, C₁ -C_Four Alkoxy, 3
Up to the following substituents, ie C₁ -C_Four Arcoki
Si, C₁ -C_Four Halogen alkoxy, C₁ -C_Four Archi
Lucio, C₁ -C_Four Halogen alkylthio, C ₁ -C_Four 
Dialkylamino, C₃ -C₈ Cycloalkyl, halogen
(But R², R³ , R^Four Is amino or hydroxy
C to mean shi₁ -C_Four Dialkylaminoethy
(Except for Le) C₁ -C₆ Alkyl, 3
Up to C₁ -C₆ Alkyl, C₁ -C₆ Halogen al
Kill, C₁ -C_Four Alkoxy, C₁ -C_Four Halogen al
C which may have boxy, halogen or nitro₃ 
-C₈ Cycloalkyl, substituted with up to 3 halogens
May be C₃ -C₆ Alkenyl or C₃ -C₆ 
Means alkynyl, R² , R³ Or R^Four At least
Also one is nitro, group OR^Five Or group NR⁶R⁷ Means
And the remaining R² , R³ Or R^Four Is the following,
Wachi (i) hydrogen, (ii) halogen, nitro or sia
No, (iii) up to 5 halogens and / or 2
Up to the following substituents, ie C₁ -C_Four Alkoxy,
C₁ -C_Four Halogen alkoxy, C₁ -C_Four Alkylchi
Oh, C₁ -C_Four Halogen alkylthio, C₃ -C₆ Shiku
Lower alkyl or cyano, (iv) C₁ -C_Four Archi
Le, C₁ -C_Four Halogen alkyl, C₁ -C_Four Arcoki
Si, C₁ -C_Four Halogen alkoxy, C₁ -C_Four Archi
Lucio, C₁ -C_FourHalogen alkylthio, halogen,
Mono-substituted to tri-substituted with cyano or nitro
Benzyl, (v) C₁ -C_Four Alkyl or
Even if mono-substituted to tri-substituted with halogen
Good C₃ -C₈ By cycloalkyl, (vi) halogen
Mono-substituted to tri-substituted and / or C₁ -C
₃ Alkoxy or phenyl (up to 3 of the following
Substituent, ie C₁ -C_Four Alkyl, C₁ -C_Four Halo
Genalkyl, C₁ -C_Four Alkoxy, C₁ -C_Four Halo
Genalkoxy, C₁ -C_Four Alkylthio, C₁ -C_Four 
Halogen alkylthio, halogen, cyano or nitro
C which may be mono-substituted with₂ 
-C₆ Alkenyl, (vii) halogen or C₁ -C
₃ Mono-substituted to tri-substituted with alkoxy, and
/ Or up to 3 of the following substituents, ie C₁ -C
_Four Alkyl, C₁ -C_Four Halogen alkyl, C₁ -C_Four 
Alkoxy, C₁ -C_Four Halogen alkoxy, C₁ -C
_Four Alkylthio, C₁ -C_Four Halogen alkylthio, ha
C which may have a rogen, cyano or nitro₂ −
C₆ Alkynyl, (viii) C₁ -C_Four Alkoxy,
C₁ -C_Four Alkylthio, C₁ -C_Four Halogen alkoki
Si, C₁ -C_Four Halogen alkylthio, C₂ -C_Five Al
Kenyloxy, C₂ -C_Five Alkynyloxy, C₁ -C
_Four Alkylsulfinyl, C₁ -C_Four Halogen alkyl
Sulfinyl, (ix) up to 3 of the following substituents,
Wachi C₁ -C_Four Alkyl, C₁ -C_FourHalogen alk
Le, C₁ -C_Four Alkoxy, C₁ -C_Four Halogen alco
Kish, C₁ -C_Four Alkylthio, C₁ -C_Four Halogen
Has ruquilthio, halogen, cyano or nitro
Optionally phenoxy or phenylthio, (x) 1
Or two heteroatoms, ie oxygen, sulfur or nitrogen
And one or two of the following substituents, ie
Chi C₁ -C₃ Alkyl, halogen, C₁ -C₃ Arcoki
Si or C₂ -C_Four Have an alkoxy carbonyl
May be a 5- or 6-membered heterocyclic group, (xi) up to 3
The following substituents at, namely C₁ -C₆ Alkyl, C₁ 
-C₆Halogen alkyl, C₁ -C₆ Alkoxy, C₁ 
-C₆ Halogen alkoxy, C₁ -C₆ Alkylthio,
C₁ -C₆ Halogen alkylthio, halogen, nitro
Or phenyl, which may have cyano, (xii) R
^Five Is hydrogen, C₁ -C_Four Alkylcarbonyl, C₁ -C_Four 
Halogen alkyl carbonyl, C₁ -C_Four Alkoxyca
Lubonyl, C₁ -C_Four Alkoxy-C₂ -C_Four Arcoki
Sicarbonyl, C₁ -C_Four Alkylcarbamoyl, C₁ 
-C_Four Dialkylcarbonyl, C₁ -C_Four Alkylsul
Honil, C₁ -C_Four Halogen alkylsulfonyl, sulphate
Famoil, C₁ -C_Four Alkylaminosulfonyl, C
₁ -C_Four Dialkylaminosulfonyl, phenylsulfo
Nyl (these are up to three substituents, ie C₁ 
-C_Four Alkyl, C₁ -C_Four Halogen alkyl, C₁ −
C_Four Alkoxy, C₁ -C_Four Halogen alkoxy, C₁ 
-C_Four Alkylthio, halogen, cyano or nitro
Group OR when meaning "may have"^Five , (Xi
ii) R⁶ Is hydrogen, C₁ -C_Four Alkyl, benzyl, C
₁ -C_Four Alkoxy or R⁷ United with means C = S
Then R⁷ Is hydrogen, C₁ -C_Four Alkyl, C₁ -C_Four Al
Kircarbonyl, C₁ -C_Four Halogen alkyl carbonate
Le, C₁-C_Four Alkoxycarbonyl, C₁ -C_Four Al
Coxy-C₂ -C_Four Alkoxycarbonyl, C₁ -C_Four 
Alkylcarbamoyl, C₁ -C_Four -Dialkylcarba
Moyle, C₁ -C_Four Alkylsulfonyl, C₁ -C_Four Ha
Rogen alkylsulfonyl, sulfamoyl, C₁ -C
_Four Alkylaminosulfonyl, C₁ -C_Four Dialkyla
Minosulfonyl, phenylsulfonyl (these are C₁ −
C_Four Alkyl, C₁-C_Four Halogen alkyl, C₁ -C_Four
 Alkoxy, C₁ -C_Four Halogen alkoxy, C₁ −
C_Four By alkylthio, halogen, cyano or nitro
Or mono-substituted to tri-substituted)
NR⁶ R⁷ Means 6-amino-5-cyano-
Excludes 4-phenylpyridine-2,3-dicarboxylic acid
Pyridine-2,3-dicarboxylic acid imide and agriculture
To be solved or achieved by a salt that can be used in a practical manner
Have been found by the present inventors.

Preferred pyridine-2,3-dicarboxylic acid imides of formula I are those wherein R ¹ is hydrogen, C ₁ -C ₆ alkyl, C ₃
-C ₆ alkenyl, C ₃ -C ₆ alkynyl, 1- (cyclopropyl) -C ₁ -C ₃ alkyl, _1-C 1 -C ₂
Means an alkyl cyclopropyl or C ₃ -C ₆ cycloalkyl, 3 groups in the pyridine ring, R ^2, R ^3, R
Two of ⁴ independently of one another each represent hydrogen, C ₁ -C ₄ alkyl (optionally substituted with up to 5 halogen atoms), C ₁ -C ₄ alkoxy, halogen or cyano, The group of 3 is (a) chlorine for R ² (6-position), and (b) fluorine, chlorine, C for R ³ (5-position).
₁ -C ₃ alkoxy, C ₂ -C ₅ alkenyloxy, C
_2- C ₅ alkynyloxy, halogen, trifluoromethyl or cyano, for (c) R ⁴ (position-6) halogen, C ₁ -C ₃ alkoxy, C ₂ -C ₅ alkenyloxy, C ₂ -C ₅ alkynyl. This is the case when it means oxy.

Particularly preferred is when at least one of R ² , R ³ and R ^{4 represents} halogen, especially fluorine or chlorine. Furthermore, it is also preferable that the pyridine ring is mono-substituted or di-substituted. The substituent R ¹ on the imide nitrogen is alkyl, especially i-propyl, s-
Butyl, branched alkyl such as t-butyl, or 1
- (cyclopropyl) - methyl, 1- (cyclopropyl) - ethyl or 1- (cyclopropyl) - is a case to mean a 1- (cyclopropyl) -C ₁ -C ₃ alkyl as propyl. The subject of the present invention is also novel intermediates such as anhydrides and fluorine-substituted pyridine-2,3-dicarboxylic acid esters. These will be described below.

First, the following formula IIa '

[0016]

[Chemical 17] And at least one of R ² , R ³ and R ⁴ means fluorine, and the remaining groups are hydrogen, fluorine, chlorine, C ₁ -C ₃
A pyridine-2,3-dicarboxylic acid anhydride, which means alkyl, C ₁ -C ₃ alkoxy, trifluoromethoxy, chlorodifluoromethoxy, methylthio, trifluoromethylthio, chlorodifluoromethylthio or methylsulfonyl. Fluoro- and 4,
Exclude 5,6-trifluoro-pyridine-2,3-dicarboxylic acid anhydride.

Particularly preferred intermediate products are 6-fluoro-pyridine-2,3-dicarboxylic acid anhydride and 5,
6-difluoro-pyridine-2,3-dicarboxylic acid anhydride.

Still other preferred compounds of the present invention have the formula IIa '

[0019]

Embedded image And R ⁴ is hydrogen, R ³ is chlorine, and C ₁ -C ₃
Alkoxy, trifluoromethyl or cyano can be replaced by R ²
Represents fluorine, chlorine, C ₁ -C ₃ alkyl, C ₁ -C ₃ alkoxy, trifluoromethoxy, chlorodifluoromethoxy, methylthio, trifluoromethylthio, chlorodifluoromethylthio or methylsulfonyl, or R ² and R ⁴ Is hydrogen and R ³ is C ₁ -C ₃ alkoxy, trifluoromethyl, cyano, trifluoromethoxy, chlorodifluoromethoxy, methylthio, trifluoromethylthio, chlorodifluoromethylthio or methylsulfonyl, pyridine-2,
It is a 3-dicarboxylic acid anhydride.

The intermediate products according to the invention based on dialkyl esters have the following formulas Va 'of 4,5- and / or
Or 6-fluoropyridine-2,3-dicarboxylic acid dialkyl ester and the following formulas Va ″ and V
It is a dialkyl ester of a ″.

[0021]

[Chemical 19] However, n in the formula is 1, 2 or 3, and R ⁵ is C ₁ -C
₄ alkyl, C ₃ -C ₅ alkenyl, C ₃ -C ₅ alkynyl, phenyl optionally substituted by halogen or C ₁ -C ₄ alkoxy.

[0022]

Embedded image However, one of R ² , R ³ and R ^{4 in} the formula means fluorine, and the remaining groups are hydrogen, chlorine, C ₁ -C ₃ alkyl, C ₁
—C ₃ alkoxy, trifluoromethoxy, chlorodifluoromethoxy, methylthio, trifluoromethylthio, chlorodifluoromethylthio or methylsulfonyl, R ⁵ is C ₂ -C ₄ alkyl, C ₃ -C ₅ alkenyl, C ₃ -C ₅ alkynyl. , Phenyl optionally substituted by halogen, C ₁ -C ₄ alkoxy.

[0023]

[Chemical 21] However, R ³ in the formula means chlorine, methyl, C ₁ -C ₃ alkoxy or cyano, and R ² and R ⁴ mean chlorine, C ₁ -C ₃ alkyl, C ₁ -C ₃ alkoxy, methylthio or methylsulfonyl. However, 4,5-dimethyl- and 5,6-dimethyl-pyridine-2,3-dicarboxylic acid diethyl ester are excluded. R ² and R ⁴ are also R ³
Means C ₁ -C ₃ alkoxy, meaning hydrogen and R ⁵ may be substituted with C ₂ -C ₄ alkyl, C ₃ -C ₅ alkenyl, C ₃ -C ₅ alkynyl, halogen. Meaning good phenyl or C ₁ -C ₄ alkoxy.

Pyridine-2,3-dicarboxylic acid imides of formula I form addition salts with organic acids or alkyl halides, or with inorganic or organic bases if either of the substituents is acidic. Converted to salt. These salts also belong to the present invention. Examples of the basic salt include alkali metal salts, especially sodium, potassium salts, alkaline earth metal salts, especially calcium, magnesium, barium salts, transition metal salts, especially manganese, copper, zinc, iron salts, and three salts. Up to C ₁ -C ₄ alkyl-hydroxy-C ₁
-C ₄ alkyl substituents and / or one phenyl or benzyl substituent may ammonium salts have a, in particular diisopropyl ammonium, tetramethyl ammonium, tetrabutyl ammonium, trimethylbenzylammonium, trimethyl - (2-hydroxyethyl ) -Ammonium salts, phosphonium salts, sulfonium salts, especially tri- (C ₁ -C ₄ ) -alkylsulfooxonium salts.

Pyridine-2,3-dicarboxylic acid imide I
When the substitution mode in (4) leads to an optically active compound, (+) and (−) optical antipodes are also included in the present invention in addition to the racemate.

Pyridine-2,3-dicarboxylic acid imide I
Can be produced by various methods as described in European Patent Application Publication No. 422456.

Compound I is, for example, pyridinedicarboxylic acid anhydride II

[0028]

[Chemical formula 22] Is a tertiary amine III (preferably in approximately stoichiometric amount) in an inert solvent.

[0029]

[Chemical formula 23] Reacted with pyridinedicarboxylic acid half amide IV

[0030]

[Chemical formula 24] It is obtained by cyclizing it with a water splitting agent.

In a more chemically specific manner, the following general formula Ia

[0032]

[Chemical 25] And R ² to R ⁴ have the meanings given above and at least one of them, two of them or all of them mean nitro. It was That is, the following general formula Ib

[0033]

[Chemical formula 26] And R ¹ to R ⁴ have the meanings given above, R
At least one from ² R ⁴ is meant chlorine, or two from R ² R ^4, or all means chlorine, a method of halogen exchange is performed potassium fluoride.

Furthermore, a process has been found in which the pyridine derivatives of the formula Ia above are likewise obtained advantageously. This method according to the invention comprises the following formula IIb:

[0035]

[Chemical 27] And R ² to R ⁴ have the meanings given above, but at least one of these, two or all of which means chlorine, is treated with potassium fluoride. The following formula IIa is obtained by halogen exchange.

[0036]

[Chemical 28] In which R ² to R ⁴ have the above-mentioned meanings, and at least one, or two or all of them have the meaning of fluorine, which is converted into a pyridinecarboxylic acid anhydride, which is the above-mentioned substituted amine. The pyridine derivative Ia is obtained by treating with.

The preparation of pyridinedicarboxylic acid half amide IV is carried out by throwing the anhydride II into an inert solvent and optionally dissolving it in an inert solvent as well, in approximately equivalent amounts of the amine I.
II was added dropwise, and after the reaction was completed, the reaction product was filtered off with suction,
Alternatively, it is carried out by evaporating and isolating the solvent used.

[0038]

[Chemical 29] The solvent used in this reaction is, for example, tetrachloroethane, methylene chloride, chloroform, chlorobenzyl, halogenated hydrocarbon such as 1,2-dichlorobenzene, diethyl ether, methyl-t-butyl ether, dimethoxyethane, diethylene glycol methyl ether. , Ethers such as tetrahydrofuran, dioxane, acetonitrile, dimethylformamide, dimethylacetamide, dimethylsulfoxide, N-methylpyrrolidone, 1,3-dimethyltetrahydro-2 (1
H) -pyrimidinone, dipolar neutral solvents such as 1,3-dimethylimidazolidinone-2, aromatic solvents such as benzene, toluene, xylene, pyridine, quinoline, ketones such as acetone, methyl ethyl ketone, and the like. It is a mixed solvent.

The reaction is carried out from -10 ° C to the reflux temperature of the solvent or mixture used, in particular from -20 ° C to + 120 ° C.

The molar ratios in which the required starting materials are reacted with one another range from 0.9: 1 to 3: 1 amine III to anhydride II. The material concentration in the solvent is 0.1 to 5 mol / l, preferably 0.2 to 2 mol / l.

The pyridinecarboxylic acid or ester and the acid anhydride used as starting materials in this method are commercially available and known in the literature, or can be produced by a generally known method. The outline is J.
Willy, And, published by Sons, Inc. "Heterocyclic,
Compounds "Volume 1, Chapter 8 R. C. Elderfield, H 22 , 150-160, EI53
1-536, EII 104-111, H 27 , 261,
EI319, EII299, 1962, published by Interscience, Publishers "The Chemistry of
Heterocyclic, Compounds ", Part 3, Chapter X. Killingburg's article, "Pyridine, And, It's Derivatives," and European Patent Application 29
See 9362 and 422456.

In this way, and as described in EP-A-422456, the corresponding 4-H-, 6-H- or 4-H-6H-pyridine-2,3-dicarboxylic acid is obtained. Acid ester-N-oxide,
By reacting with phosphoryl halide, a novel 4-position, 6-position, 4,6- (di) halogen-substituted pyridine-2,3-dicarboxylic acid ester can be obtained.
In the course of this transition, the halogen first moves to the 6-position and occupies it, thus the halogen enters the 4-position.

Cyclization of the half-amide IV is a conventional water-splitting agent,
For example acetohydride or thionyl chloride,
It is carried out by dehydration with an inorganic acid such as phosgene, phosphorus trichloride or phosphorus tetrachloride, or a halide, whereby it is converted into a pyridine derivative I. This reaction is carried out by throwing a carboxylic acid amide into an inert organic solvent, adding a water-decomposing agent to the inert organic solvent in the same manner, and then adding this dropwise. The reaction mixture solution is subjected to a conventional method such as hydrolysis with water and filtration by suction or extraction with an organic solvent, and evaporation and concentration of the organic solvent.

[0044]

Embedded image As the solvent in this reaction, tetrachloroethane,
Methylene chloride, chloroform, chlorobenzene,
Halogenated hydrocarbons such as 1,2-dichlorobenzene, diethyl ether, methyl-t-butyl ether,
Ethers such as dimethoxyethane, diethylene glycol dimethyl ether, tetrahydrofuran, dioxane, acetonitrile, dimethylformamide, dimethylacetamide, dimethylsulfoxide, N-methylpyrrolidone, 1,3-dimethyltetrahydro-2 (1
H) -pyrimidinone, a dipolar neutral solvent such as 1,3-dimethylimidazolidinone-2, benzene, toluene,
It is preferable to use aromatic solvents such as xylene, pyridine, quinoline, ketones such as acetone and methyl ethyl ketone, or a mixed solvent thereof.

The reaction is carried out at temperatures from -10 ° C to the reflux temperature of the respective solvent used, in particular from 0 ° C to + 150 ° C.

The molar ratios of the starting compounds used to react with each other are 0.9: 1 to 5: water-decomposing agent to acid amide.
The range is 1.

The concentration of the starting materials in the (mixed) solvent is generally from 0.1 to 5 mol / l, in particular 0.
2 to 2 mol / l.

A preferred method for the preparation of compounds Ia in which at least one of R ² to R ⁴ is fluorine or the two or three radicals are fluorine is the corresponding chlorine substitution The halogen exchange of the pyridine derivative with potassium fluoride.

This reaction is carried out by treating the pyridine derivative Ib with potassium fluoride in the presence of a polar solvent at 70 to 250 ° C., especially 80 to 200 ° C.

[0050]

[Chemical 31] Solvents used for this reaction include nitriles such as acetonitrile, propionitrile, butyronitrile and isobutyronitrile, glycol ethers such as dimethyl glycol ether, diethyl glycol ether and diethylene glycol dimethyl ether, D
MF, carboxamide such as N-methylpyrrolidone, tetraethylurea, tetrabutylurea, dimethyleneurea, urea such as dimethylpropyleneurea, sulfoxide such as dimethylsulfoxide, especially dimethylsulfone, diethylsulfone, tetramethylenesulfone Sulfones such as (sulfolane) and pentamethylene sulfone are preferred. In the method of the present invention, this reaction can be carried out in a molten state without using a solvent.

The halogen exchange proceeds at a sufficiently high rate without using a catalyst, but the reaction can be promoted by adding a catalyst such as crown ether or cryptand. This is an organic complexing ligand which acts particularly favorably due to the alkaline bond. Konta for this production
kte (1977), pages 11-31 and 36-4.
Please refer to page 8. Crown ethers as catalysts are, for example, 12-crown-4, 14-crown-4,
Dibenzo-14-crown-4, 18-crown-5,
18-crown-6, dibenzo-18-crown-6,
Aza-18-Crown-6. These catalysts are used in an amount of 0.1 to 2 mol% relative to 1 mol of the starting compound Ib.

The ratio of the starting compounds which can be reacted with one another, ie potassium fluoride, to the pyridine derivative, is 0.9: 1 to 2.0: 1, preferably 1.1: 1 to 1.3: 1. The concentration of the reaction material in the solvent is 0.1 to 5 mol / l, preferably 0.2 to 2 mol / l.

The preparation of the compounds Ia is carried out by the pyridine derivative Ib, for example in the presence of aliphatic sulfones, at temperatures up to 150 ° C., preferably 50 to 1 before the intrinsic halogen exchange.
0.1 to 0.4 mol of sulfurous acid or carbonic acid chloride at a temperature of 20 ° C., preferably 70 to 100 ° C.
It is advantageous to treat from 1.0 to 0.3 mol and then to react the reaction mixture with potassium fluoride at 70 to 250 ° C, especially 80 to 200 ° C.

Suitable catalysts in this process step are N, N-disubstituted carboxylic acid amides such as DMF, N, N-dimethylacetamide, N, N-diisopropylacetamide. Preference is given to using amounts of 0.2 to 2% by weight, based on the acid chloride.

During the reaction with the acid chloride, this is preferably done for a period of time before gas evolution is no longer observed. Excess acid chloride is recommended to be removed by sparging with an inert gas such as nitrogen or under vacuum. To do this, pre-dry the potassium fluoride,
It is desirable to maintain the resulting mixture with stirring at the reaction temperature for 1 to 10 hours.

In the method of the present invention, as the fluorinated salt, in addition to the above-mentioned potassium chloride, tetraalkyl- (C ₁
-C ₁₃₎ - ammonium fluoride and mixtures of these mixtures with one another or cesium fluoride or rubidium fluoride may also be used, but a mixture of cesium fluoride should not contain more than 50% by weight of cesium fluoride. The fluoride mixture contains at least 75% by weight, especially 90% by weight potassium fluoride, a maximum of 10% by weight of cesium fluoride or 60% by weight of potassium fluoride,
Preference is given to using mixtures which contain 40% by weight of rubidium fluoride. A more preferred halogen exchange agent is composed solely of potassium fluoride.

As the phase transfer catalyst, a quaternary ammonium salt or a phosphonium salt is used. Suitable salts include tetraalkyl- (C ₁ -C ₁₈ ) -ammonium chloride, bromide and fluoride, tetraalkyl- (C ₁ -C ₁₈ ) -phosphonium chloride and bromide, tetraphenylphosphonium chloride and bromide, (phenyl) _m (alkyl-C ₁ -C
₁₈ ) _n -phosphonium chloride and bromide (m
Means 1 to 3, n means 3 to 1, and m + n is 4.). Also, a mixture of these salts can be used. The selection of the appropriate catalyst in each case for the compound to be reacted can be carried out in simple experiments. The method described in EP-A-146924 significantly improves the space load and the yield. Device downtime and overall device cost are significantly improved by the method of the present invention.

As the phase transfer catalyst, oligo- or polyalkylene glycol dimethyl ether can also be used. However, the alkylene group preferably has 2 to 6 carbon atoms, especially 2 or 3 carbon atoms, and is an ethylene and / or propylene group, especially an ethylene group. O- ethylene (glycol) number of units are in the compound _{(-O-CH 2 -CH 2 -} ) and /
Alternatively, ethers having O-propylene units n = 4 (for example tetraethylene glycol dimethyl ether) to n = about 150, but in particular n = 4 to n = 25, are preferred. In the case of alkylene groups having 3 or more carbon atoms, n generally does not exceed 6.
The amount of this ether, especially glycol ether, is
It is generally from 0.5 to about 100% by weight, especially from about 10 to about 50% by weight, based on the fluoride used. The particular advantages of using such compounds are:
Generally, the amount of solvent can be correspondingly reduced. This is because glycol ether is usually liquid at the reaction temperature. Mixtures of these various ethers or mixtures with ammonium or phosphonium salts, especially with quaternary phosphonium salts, can also be used advantageously.

When tetraalkyl- (C ₁ -C ₁₈ ) -ammonium fluoride is used as a salt in the method of the present invention, this may shorten the reaction time, but it is not always essential. It is likewise possible to add acid binders such as alkali metal or alkaline earth metal carbonates or basic action oxides such as magnesium oxide or the corresponding mixtures for treatment. Particularly preferred is 1 to 1 based on the amount of fluoride salt used.
0% by weight, especially about 4 to 6% by weight of potassium carbonate.

These acid binders are not essential for the progress of the reaction. In some cases, hydrogen fluoride is formed during the reaction, which may significantly reduce the reaction rate.
In such a case, it is advantageous to add this kind of compound during the fractionation of the reaction mixture or the crude product from the viewpoint of preventing corrosion in the fractionation apparatus, and the use of magnesium oxide is particularly preferable. For this purpose, it is preferred to use up to about 10% by weight, in particular 3 to 8% by weight, of acid scavenger in the fractional distillation, based on the total distillation bottoms.

After the reaction with the alkali metal fluoride, the treatment is carried out by a conventional method known per se, for example, washing of the solid content by filtration, distillation of the filtrate, washing filtration and the like. When using a water-miscible solvent, the pyridine derivative Ia is precipitated by addition of water and can be treated as described above.

When at least one of R ² to R ⁴ represents fluorine, the compound of formula IIa can be prepared by halogen exchange of pyridinecarboxylic acid anhydride IIb with potassium fluoride and the same procedure as described above. It is carried out by reacting the pyridine derivative Ib.

[0063]

Embedded image Instead of performing at the stage of pyridinecarboxylic anhydride IIb,
The halogen exchange can also be carried out with the corresponding diester Vb. This can then be converted to the anhydride IIa by hydrolysis and cyclization or directly reacted with amine III to the carboxylic acid half amide VI and cyclized by hydrolysis to the compound Ia of the invention. .

The following formula Va

[0065]

[Chemical 33] And at least one of R ² to R ⁴ represents fluorine, and R ⁵ is an optionally substituted alkel, alkenyl or alkynyl, for example, halogen-C ₁ -C ₄
Alkyl, halogen -C ₃ -C ₅ alkenyl, halogen -C ₃ -C ₅ alkynyl, C ₁ -C ₄ alkoxy -C ₁
-C ₄ alkyl, C ₁ -C ₄ alkoxy -C ₃ -C ₅ alkenyl, C ₁ -C ₄ alkoxy -C ₃ -C ₅ alkynyl, phenyl -C ₁ -C ₄ alkyl, phenyl -C ₃ -
A method for producing a pyridinedicarboxylic acid ester in the case of meaning C ₅ alkenyl and phenyl-C ₃ -C ₅ alkynyl is as follows.

[0066]

Embedded image And R ² to R ⁵ have the meanings given above,
It is carried out by halogen-exchange of pyridinedicarboxylic acid ester in which at least one of R ² to R ⁴ is a base with potassium fluoride.

This reaction is carried out in the same manner as the above-mentioned reaction of the pyridine derivative Ib, and then the conversion to the pyridine derivative Ia is carried out.

[0068]

Embedded image The molar proportions of the materials used and the method embodiments are described in compound IV
Alternatively, the reaction is carried out under the reaction conditions for producing Ia, or by a method known in the literature.

In the production of the compound of the present invention, the compound represented by the following general formula Va ′ ″, wherein R ³ represents C ₁ -C ₃ alkoxy, and R ² and R ⁴ represent hydrogen: Alkoxy-pyridine-2,3-dicarboxylic acid esters include alkoxyacrolein VII and 2-amino-3-
It has been found to be advantageously obtained by condensing the chloromaleic acid dialkyl ester VIII.

[0070]

Embedded image In this case, the 2-amino-3-chloromaleic acid dialkyl ester VIII is added to the lower aliphatic carboxylic acid, optionally in the inert solvent mentioned above, and a further 3
Grade base is added, and then alkoxyacrolein VII
Convert to.

The addition of the tertiary base is generally from 60 to 12
The addition of the alkoxyacrolein VII is generally carried out at a temperature of 80 to 160 ° C., especially 110 to 130 ° C., at a temperature of 0 ° C., especially 70 to 90 ° C.

The molar ratio of acrolein VII and 2-amino-3-chloromaleic acid dialkyl ester VIII to be reacted with one another is from 0.9: 1 to 1.
5: 1, especially 1.1: 1 to 1.1: 1. Tertiary base is 0.9: based on maleic acid diester VIII:
1 to 1.5: 1, especially 1.1: 1. The concentration of the reaction material in the solvent is 0.1 to 5 mol / l,
Especially 0.3 to 2 mol / l.

As the aliphatic carboxylic acid, formic acid, acetic acid,
Propionic acid, butyric acid and isobutyric acid are suitable, and examples of tertiary bases include amines such as triethylamine, tripropylamine and tributylamine, pyridine and α.
Aromatic bases such as-, β-, γ-pyricon, 2,4- and 2,6-lutidine, quinoline, and further N, N-
N, N-dialkylanilines such as dimethylaniline, N, N-diethylaniline can be used.

The mixture is subjected to conventional treatment, such as vacuum concentration,
The residue is washed with water, filtered off with suction of the product in an organic solvent, extracted and concentrated (see EP 371499).

In contrast to the prior art, the novel fluorine-substituted pyridine-2,3-dicarboxylic acid anhydrides, esters and imides according to the invention are obtained in a particularly simple manner and in high yields. Fluorine-substituted diesters were also unknown.
In a series of anhydrides, 5-fluoro substitution or 4,
The method for producing a 5,6-trifluoro-substituted pyridine derivative itself is described in J. Org. Chem, 26 , 808 (19
61) and J. et al. Fluorine. Chem, 7 , 3
63 (1976). In both methods, the fluorine-substituted quinoline must first be formed in a cumbersome manner and then again oxidatively decomposed. Moreover, the yield of 5-fluoropyridine-2,3-dicarboxylic acid obtained by electrochemical oxidation is only 26%, and in the case of nitric acid oxidation of heptafluoroquinoline, 2,3,4,5,5.
6,7-Heptafluoro-5,8-dioxo-5,8-
20% dihydroquinoline, 3,4,5,6,7,8-
In addition to 12% hexafluoro-2-oxo-1,2-dihydroquinoline, only 5% of the anhydride, 4,
Only 5,6-trifluoropyridine-2,3-dicarboxylic acid anhydride is obtained.

In view of the specific use of the compound I of the present invention, the following groups are suitable as the respective substituents in the formula.

First, R ¹ is hydrogen, C ₁ -C ₄ alkoxy,
For example, methoxy, ethoxy, propoxy, 1-methylethoxy, butoxy, 1-methylpropoxy, 2-methylpropoxy, 1,1-dimethylethoxy, especially methoxy, ethoxy, 1-methylethoxy and 1,1-dimethylethoxy. And C ₁ -C ₆ alkyl such as methyl, ethyl, propyl, 1-methylethyl, butyl, 1-methylpropyl, 2-methylpropyl, 1,1
-Dimethylethyl, pentyl, 1-methylbutyl, 2-
Methylbutyl, 3-methylbutyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, 2,2-dimethylpropyl, 1-ethylpropyl, hexyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl,
4-methylpentyl, 1,1-dimethylbutyl, 1,2
-Dimethylbutyl, 1,3-dimethylbutyl, 2,2-
Dimethylbutyl, 2,3-dimethylbutyl, 3,3-dimethylbutyl, 1-ethylbutyl, 2-ethylbutyl,
1,1,2-trimethylpropyl, 1,2,2-trimethylpropyl, 1-ethyl-1-methylpropyl, 1-
It means ethyl-2-methylpropyl, especially propyl, 1-methylethyl and 1,1-dimethylethyl.
However, these are up to three substituents, namely C ₁ -C ₄ alkoxy as described above, especially methoxy, ethoxy, C ₁ -C ₄ halogenalkoxy, such as difluoromethoxy, trifluoromethoxy, chlorodifluoromethoxy, Dichlorofluoromethoxy, 1-fluoroethoxy, 2-fluoroethoxy, 2,2-difluoroethoxy, 1,1,2,2-tetrafluoroethoxy,
2,2,2-trifluoroethoxy, 2-chloro-1,
1,2-trifluoroethoxy, pentafluoroethoxy, especially trifluoromethoxy and pentafluoroethoxy, C ₁ -C ₄ alkylthio, such as methylthio, ethylthio, propylthio, 1-methylethylthio, n-butylthio, 1-methylpropyl Thio, 2-methylpropylthio, 1,1-dimethylethylthio, especially methylthio and ethylthio, C ₁ -C ₄ halogenalkylthio, such as difluoromethylthio, trifluoromethylthio, chlorodifluoromethylthio, 1-fluoroethylthio, 2- Fluoroethylthio, 2,2-difluoroethylthio, 2,2,2-trifluoroethylthio, 2-chloro-2,2-difluoroethylthio,
2,2-dichloro-2-fluoroethylthio, 2,2
2-trichloroethylthio, pentafluoroethylthio, especially trifluoromethylthio and pentafluoroethylthio, (C ₁ -C ₄ dialkyl) amino, such as dimethylamino, diethylamino, dipropylamino, diisopropylamino, dibutylamino, methylethyl. Amino, especially dimethylamino and methylethylamino, C ₃ -C ₈ cycloalkyl, such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclooctyl, especially cyclopropyl, cyclopentyl and cyclohexyl, halogen, such as fluorine,
It may be replaced by chlorine, bromine, iodine, especially fluorine chlorine.

R ¹ is further C ₃ -C ₈ cycloalkyl,
For example cyclopropyl, cyclobutyl,
It means cyclopentyl and cyclohexyl, and these are 3
Up to the following substituents, ie C ₁ -as defined above:
C ₆ alkyl, especially methyl, ethyl, isopropyl,
Halogen alkyl as described above, especially trifluoromethyl, C ₁ -C ₄ alkoxy as described above, especially methoxy, ethoxy, halogen alkoxy as described above, especially trifluoromethoxy, halogen as described above, It may have fluorine and chlorine.

R ¹ is further C ₃ -C ₆ alkenyl, such as 2-propenyl, 2-methylethenyl, 2-butenyl, 3-butenyl, 1-methyl-2-propenyl, 2-
Methyl-2-propenyl, 2-pentenyl, 3-pentenyl, 4-pentenyl, 3-methyl-2-butenyl, 1
-Methyl-2-butenyl, 2-butenyl, 1-methyl-
3-butenyl, 2-methyl-3-butenyl, 1,1-dimethyl-2-propenyl, 1,2-dimethyl-2-propenyl, 1-ethyl-2-propenyl, 1-hexenyl, 2-hexenyl, 3- Hexenyl, 4-hexenyl, 5-hexenyl, 1-methyl-2-pentenyl, 2
-Methyl-2-pentenyl, 3-methyl-2-pentenyl, 4-methyl-2-pentenyl, 1-methyl-3-pentenyl, 2-methyl-3-pentenyl, 3-methyl-
3-pentenyl, 4-methyl-3-pentenyl, 1-methyl-4-pentenyl, 2-methyl-4-pentenyl,
3-methyl-4-pentenyl, 4-methyl-4-pentenyl, 1,1-dimethyl-2-butenyl, 1,1-dimethyl-3-butenyl, 1,2-dimethyl-2-butenyl, 1,2- Dimethyl-3-butenyl, 1,3-dimethyl-2-butenyl, 1,3-dimethyl-3-butenyl,
2,3-dimethyl-2-butenyl, 2,3-dimethyl-
3-butenyl, 1-ethyl-2-butenyl, 1-ethyl-3-butenyl, 2-ethyl-2-butenyl, 2-ethyl-3-butenyl, 1,1,2-trimethyl-2-propenyl, 1- Ethyl-1-methyl-2-pentenyl, ethyl-2-methyl-2-pentenyl, especially ethenyl,
2-propenyl, 1-methylethenyl, 2-butenyl,
3-butenyl, 1-methylpropenyl, 1-methyl-2
-Propenyl, 2-methyl-2-propenyl, which may be mono- to tri-substituted with halogen, especially fluorine, chlorine.

R ¹ is further C ₃ -C ₆ alkynyl, for example propargyl, 2-butynyl, 3-butynyl, 1-methyl-2-propynyl, 2-pentynyl, 3-pentynyl, 1-methyl-3-butynyl, 2 -Methyl-3-butynyl, 1-methyl-2-butynyl, 3-methyl-1-butynyl, 1,1-dimethyl-2-propynyl, 1-ethyl-2-propynyl, 2-hexynyl, 3-hexynyl, 4 -Hexynyl, 5-hexynyl, 1-methyl-2
-Pentynyl, 1-methyl-3-pentynyl, 1-methyl-4-pentynyl, 3-methyl-4-pentynyl, 4
-Methyl-2-pentynyl, 1,1-dimethyl-2-butynyl, 1,1-dimethyl-3-butynyl, 1,2-dimethyl-3-butynyl, 2,2-dimethyl-3-butynyl, 1-ethyl -2-butynyl, 1-ethyl-3-butynyl, 1-ethyl-1-methyl-2-propynyl, 1,
1-dimethyl-2-propynyl, especially 1-methyl-2
-Propynyl and 1,1-dimethyl-2-propynyl, which may be mono- to tri-substituted by the halogens mentioned above, especially fluorine, chlorine, and / or mono-substituted by phenyl. Good.

R ² , R ³ and R ⁴ are hydrogen, the halogens mentioned above for R ¹ , especially fluorine and cyano, the alkyls mentioned above for R ¹ , especially methyl, ethyl, propyl, 1-methylethyl, 1,1. Means dimethylethyl, which means 1 to 5 halogens mentioned above for R ¹ , in particular fluorine, chlorine and / or one or two of the following substituents, ie C ₁ mentioned above for R ^1. C ₄ alkoxy, especially methoxy, ethoxy, 1-methylethoxy, 1,1-dimethylethoxy, C mentioned above for R ^1.
₁ -C ₄ -haloalkoxy, in particular halogen-methoxy, e.g. difluoromethoxy, trifluoromethoxy, C ₁ -C ₄ alkylthio described above per R ^1, in particular methylthio, ethylthio, C ₁ described above per R ¹ -
C ₄ halogenalkylthio, especially difluoromethylthio, trifluoromethylthio, C ₃ mentioned above for R ^1.
It may have -C ₆ cycloalkyl, especially cyclopropyl.

R ² , R ³ and R ⁴ also mean benzyl, which is C ₁ -C ₄ alkyl as defined above for R ¹ .
In particular methyl, ethyl, 1-methylethyl, C ₁ -C ₄ halogenalkyl mentioned above for R ¹ , especially trifluoromethyl, chlorodifluoromethyl, C ₁ -C ₄ alkoxy mentioned above for R ¹ , especially methoxy, ethoxy, C ₁ described above C ₁ -C ₄ halogen mentioned above per R ¹ alkoxy, especially trifluoromethoxy, trichloromethoxy, pentafluoroethoxy, per R ¹
-C ₄ alkylthio, in particular methylthio, ethylthio,
C ₁ -C ₄ halogenalkylthio as defined above for R ¹ ,
It may in particular be monosubstituted to trisubstituted by difluoromethylthio, trifluoromethylthio, pentafluoromethylthio, halogen, especially fluorine, chlorine, cyano, nitro.

R ² , R ³ and R ⁴ also mean C ₃ -C ₈ cycloalkyl as defined above for R ¹ , especially cyclopropyl, cyclopentyl, cyclohexyl, which are C ₁ -C as defined above for R ^1. _It may be mono- to tri-substituted by ₄ alkyl, especially methyl, ethyl, the halogens mentioned above for R ¹ , especially fluorine, chlorine.

R ² , R ³ and R ⁴ are further C ₂ -C ₆ alkenyl as defined above for R ¹ , especially 1-ethenyl, 1-
Propenyl, 1-methyl-1-propenyl, 2-methyl-1-propenyl, 1-pentenyl, 1-methyl-1-
Butenyl, 2-methyl-1-butenyl, 1-ethyl-1
-Propenyl, 1-methyl-1-pentenyl, 2-methyl-1-pentenyl, 3-methyl-1-pentenyl, 4
-Methyl-1-pentenyl, 1,2-dimethyl-1-butenyl, 1,3-dimethyl-1-butenyl, 2,3-dimethyl-1-butenyl, 3,3-dimethyl-1-butenyl, ethyl-1 -Butenyl, 2-ethyl-1-butenyl, 1-ethyl-2-methyl-1-pentenyl, especially ethenyl, 1-propenyl, 2-propenyl, 1-methylethenyl, 1-butenyl, 2-butenyl, 3-butenyl. , 1-methylpropenyl, 1-methyl-2-propenyl, 2-methyl-1-propenyl, 2-methyl-2-propenyl, which are the halogens mentioned above for R ¹ , especially fluorine, chlorine, R C ₁ described above ^per -
C ₃ alkoxy, especially methoxy, ethoxy, may be mono- to tri-substituted and / or R
¹ may be mono-substituted by the phenyl mentioned above, and this phenyl may be up to three substituents below, namely the alkyl mentioned above for R ¹ , especially methyl, ethyl, 1-methylethyl, the above mentioned for R ^1. Halogen alkyl, especially trifluoromethyl, chlorodifluoromethyl, alkoxy mentioned above for R ¹ , especially methoxy, ethoxy, halogen alkoxy mentioned above for R ¹ , especially trifluoromethoxy, trichloromethoxy, pentafluoroethoxy, R ¹ alkylthio described above per, in particular methylthio, ethylthio, haloalkyl thio described above per R ^1, in particular difluoromethylthio, trifluoromethylthio, pentafluoroethyl methyl thio, halogen mentioned above per R ^1, in particular fluorine, chlorine, cyano or nitro You can have me.

R ² , R ³ and R ⁴ are the above-mentioned C for R ^1.
₂ -C ₆ alkynyl, in particular ethynyl, 1-propenyl, 1-butynyl, 1-pentynyl, 1-hexynyl,
It means 3-methyl-1-pentynyl, 4-methyl-1-pentynyl, especially ethynyl, 1-propynyl, propargyl, which are halogens mentioned above, especially fluorine, chlorine, alkoxy mentioned above, especially methoxy, It may be mono- to tri-substituted with ethoxy and / or mono-substituted with phenyl. However, that phenyl is up to three further substituents, namely the above-mentioned alkyl, especially methyl, ethyl, 1-methylethyl, the above-mentioned halogenalkyl, especially trifluoromethyl, chlorodifluoromethyl, the above-mentioned alkoxy, Especially methoxy, ethoxy, the above mentioned halogen alkoxy, especially trifluoromethoxy,
Trichloromethoxy, pentafluoroethoxy, alkylthio mentioned above, especially methylthio, ethylthio, halogenalkylthio mentioned above, especially difluoromethylthio, trifluoromethylthio, pentafluoromethylthio, halogen mentioned above, especially fluorine, chlorine, cyano or nitro May be.

R ² , R ³ and R ⁴ are also C ₁ -C ₄ alkoxy or C ₁ -C ₄ alkylthio as defined above for R ¹ , especially methoxy, ethoxy, methylthio, ethylthio, C ₁ -C ₄ halogen as defined above. Alkoxy or C ₁
-C ₄ halogenalkylthio, especially trifluoromethoxy, trichloromethoxy, pentafluoroethoxy,
It means difluoromethylthio, trifluoromethylthio, pentafluoroethylthio.

R ² , R ³ and R ⁴ are each further C ₂ -C ₅ alkenyloxy, especially vinyloxy, 2-propenyloxy, 1-methylethenyloxy, 2-methyl-3-butenyloxy, especially 2-propenyl. oxy, 2-methyl-3-butenyloxy, C ₂ -C ₅ alkynyloxy, e.g. ethynyloxy, 2-propynyloxy, 1
-Methylethynyloxy, 2-methyl-3-butynyloxy, especially 2-propynyloxy, 2-methyl-3-
Butenyloxy, C ₁ -C ₄ alkylsulfinyl, such as methylsulfinyl, ethylsulfinyl, n-propylsulfinyl, i-propylsulfinyl, n-
Butylsulfinyl, t-butylsulfinyl, especially methylsulfinyl, C ₁ -C ₄ alkylsulfonyl,
For example, methylsulfonyl, ethylsulfonyl, n-propylsulfonyl, i-propylsulfonyl, n-butylsulfonyl, t-butylsulfonyl, especially methylsulfonyl, C ₁ -C ₄ halogenalkylsulfonyl, such as trifluoromethylsulfonyl, pentafluoroethyl. By sulfonyl is meant monofluorobutylsulfonyl, especially trifluoromethylsulfonyl.

R ² , R ³ and R ⁴ also mean phenoxy or phenylthio, which are C ₁ -C ₄ alkyl as defined above for R ¹ , especially methyl, ethyl, 1-isopropyl and R ^{1 as} defined above. Halogen alkyl, especially trifluoromethyl, chlorodifluoromethyl, R
¹ above alkoxy, especially methoxy, ethoxy, R ¹ above halogenalkoxy, especially trifluoromethoxy, trichloromethoxy, pentafluoroethoxy, above alkylthio, especially methylthio, ethylthio, above halogenalkylthio, especially It may be mono- to tri-substituted with difluoromethylthio, trifluoromethylthio, pentafluoromethylthio, the halogens mentioned above, especially fluorine, chlorine, cyano, nitro.

R ² , R ³ and R ⁴ are 5- or 6-membered saturated or aromatic heterocyclic groups having 1 or 2 oxygen, sulfur or nitrogen as a hetero atom, for example, tetrahydrofuryl, tetrahydrofuranyl, furyl. , Thienyl, thiazolyl, pyrazolyl, pyrrolyl, pyridyl,
Morpholino, piperidino, pyrimidyl, especially 2-tetrahydrofuranyl, 3-tetrahydrofuranyl, 2-tetrahydrothienyl, 3-tetrahydrothienyl, 2-
Tetrahydropyranyl, 3-tetrahydropyranyl, 4
-Tetrahydropyranyl, 2-furyl, 3-furyl, 2
-Thienyl, 3-thienyl, 3-isoxazolyl, 4
-Isoxazolyl, 5-isoxazolyl, 3-isothiazolyl, 4-isothiazolyl, 5-isothiazolyl, 2-oxazolyl, 4-oxazolyl, 5-oxazolyl, 2-thiazolyl, 4-thiazolyl, 5-thiazolyl, 2-imidazolyl, 4-imidazolyl , 5-imidazolyl, 2-pyrrolyl, 3-pyrrolyl, 3-pyrazolyl, 4-pyrazolyl, 5-pyrazolyl, 2-pyridyl,
It means 3-pyridyl and 4-pyridyl, but these are 3
Up to the following substituents, namely C ₁ -C ₃ alkyl mentioned above, especially methyl, ethyl, halogen mentioned above, especially fluorine, chlorine, C ₁ -C ₃ alkoxy mentioned above, especially methoxy, ethoxy, C _1- C ₄ alkoxycarbonyl, such as methoxycarbonyl, ethoxycarbonyl,
In particular, it means methoxycarbonyl or phenyl.
The phenyl itself may have up to 3 substituents, such as C ₁ -C ₆ alkyl mentioned above for R ¹ , in particular methyl, ethyl, isopropyl, C ₁ -C ₆ halogenalkyl mentioned above, especially trifluoromethyl, Chlorodifluoromethyl, C ₁ -C ₆ alkoxy mentioned above, especially methoxy, ethoxy, C ₁ -C ₆ halogen alkoxy mentioned above, especially trifluoromethoxy, trichloromethoxy, pentafluoroethoxy, C ₁ -C ₆ alkylthio mentioned above. It may have, in particular, methylthio, ethylthio, the abovementioned halogenalkylthio, especially difluoromethylthio, trifluoromethylthio, pentafluoromethylthio, the abovementioned halogens, in particular fluorine, chlorine, cyano, nitro.

However, one of the three R ² , R ³ and R ⁴ has the meaning defined at the beginning.

Preferred combinations of groups in the pyridine ring are shown in the table below. R ¹ is L1 to L64 in the table that follows the table below
Is preferred, especially preferably 1- (cyclopropyl) -ethyl or cyclopropyl.

[0092]

Embedded image

[0093]

[Table 1]

[0094]

[Table 2]

[0095]

[Table 3]

[0096]

[Table 4]

[0097]

[Table 5]

[0098]

[Table 6]

[0099]

[Table 7]

[0100]

[Table 8]

[0101]

[Table 9]

[0102]

[Table 10]

[0103]

[Table 11]

[0104]

[Table 12]

[0105]

[Table 13]

[0106]

[Table 14]

[0107]

[Table 15]

[0108]

[Table 16] Compound I, a herbicide containing it or an environment-friendly alkali metal and alkaline earth metal salt thereof,
When cultivating rice, corn, soybeans, cotton, etc., weeds and harmful herbs can be satisfactorily controlled without harming cultivated plants, and the advantage that the above-mentioned effects can be obtained even in a low use amount is advantageous. Have.

Compound I or a herbicide containing the same is
Sprayable directly in the form of solutions, powders, suspensions, concentrated aqueous, oily or other suspensions or dispersions, emulsions, oily dispersions, pastes, dusts, dusts or granules, It can be applied by the mist method, dust method, spray method or injection method. The application form depends entirely on the intended use; in each case, the finest possible distribution of the active substances according to the invention should be ensured.

Mixture I is generally preferably used for producing directly dispersible solutions, emulsions, pastes or oil dispersions. As the inert additives, medium to high boiling point mineral oil fractions such as kerosene or diesel oil, further coal tar oil, and oils of vegetable or animal origin, aliphatic, cyclic and aromatic hydrocarbons, For example, paraffin, tetrahydronaphthalene, alkyl-substituted naphthalene or a derivative thereof, alkylated benzene or a derivative thereof, methanol, ethanol, propanol, butanol, cyclohexanol, cyclohexanone, a strongly polar solvent such as N-methylpyrrolidone, water is used.

Aqueous use forms can be prepared by adding water to emulsion concentrates, suspensions, pastes or wettable or water-dispersible powders. For the production of emulsions, pastes or oil dispersions, the substances can be mixed neat or in the oil or solvent and mixed homogeneously in water with wetting agents, adhesives, dispersants or emulsifiers. . It is also possible to prepare concentrates which consist of the active substances, wetting agents, adhesives, dispersants or emulsifiers and optionally solvents or oils, which are suitable for dilution with water.

The surface-active substances include: aromatic sulfonic acids, for example the alkali salts of ligninsulfonic acid, phenolsulfonic acid, naphthalenesulfonic acid, dibutylnaphthalenesulfonic acid,
Alkaline earth salts, ammonium salts, and fatty acid, alkyl sulfonates, alkylaryl sulfonates, alkyl sulfates, lauryl ether sulfates, alkaline salts and alkaline earth salts of fatty alcohol sulfates, ammonium salts, and sulfation Hexadecanol, heptadecanol and octadecanol salts, and salts of sulfated fatty alcohol glycol ethers, condensation products of sulfonated naphthalene and naphthalene derivatives with formaldehyde, naphthalene or naphthalene sulfonic acid with phenol and formaldehyde Condensation products with, polyoxyethylene octylphenol ether, ethoxylated isooctylphenol,
Octylphenol, nonylphenol, alkylphenol polyglycol ether, tributylphenyl polyglycol ether, alkylaryl polyether alcohol, isotridecyl alcohol, fatty alcohol ethylene oxide-condensate, ethoxylated castor oil, polyoxyethylene alkyl ether, or polyoxypropylene, Lauryl alcohol polyglycol ether acetate, sorbit ester, lignin-sulfite waste liquor and methylcellulose.

Powders, dusters and sprinkles can be prepared by mixing or grinding the active substances with a solid carrier substance.

Granules, for example coated, impregnated and homogeneous granules, can be prepared by binding the active substances to solid carrier substances. Solid carrier materials are, for example, mineral earth, for example silica gel, silicic acid, silicate gels, silicates, talc, kaolin, limestone, lime, chalk, agglomerated soil, calcareous yellow clay, clay, dolomite, diatomaceous earth, calcium sulfate, sulfuric acid. Magnesium, magnesium oxide, ground synthetic resins, fertilizers such as ammonium sulphate, ammonium phosphate, ammonium nitrate, urea and vegetable products such as cereal flour, bark, wood and walnut flour, fibrin powder and other solid carrier materials.

In the use form, the effective substance is usually 0.01 to 95.
% By weight, in particular 0.5 to 90% by weight. In this case, the active substance has a purity of 90 to 100%, especially 95 to 100% (N
According to the MR spectrum).

Formulation examples are as follows.

I. 20 parts by weight of compound No. 1.031
80 parts by weight of alkylated benzene, 10 parts by weight of an addition product obtained by adding 8 to 10 mol of ethylene oxide to 1 mol of oleic acid-N-monoethanolamide, 5 parts by weight of a calcium salt of dodecylbenzolsulfonic acid and 40 parts of ethylene oxide. Mol is added to a mixture of 5 parts by weight of addition product added to 1 mol of castor oil. By pouring the mixture into 100,000 parts by weight of water and finely distributing it, an aqueous dispersion containing 0.02% by weight of the active substance is obtained.

II. 20 parts by weight of compound No. 1.03
40 parts by weight of cyclohexanone and 3 parts of isobutanol
0 parts by weight, addition product obtained by adding 7 mol of ethylene oxide to 1 mol of isooctylphenol, addition product obtained by adding 40 mol of ethylene oxide to 1 mol of castor oil 1
It dissolves in a mixture of 0 parts by weight. Add this solution to water 1
Active ingredient 0.0 by injecting into 00000 parts by weight
An aqueous dispersion containing 2% by weight is obtained.

III. 20 parts by weight of compound No. 1.0
31 is dissolved in a mixture of 25 parts by weight of cyclohexanone, 65 parts by weight of a mineral oil fraction with a boiling point of 210 to 280 ° C. and 10 parts by weight of the addition product of 40 mol of ethylene oxide added to 1 mol of castor oil. 100 parts of this solution
By pouring in 000 parts by weight, an aqueous dispersion containing 0.02% by weight of the active substance is obtained.

IV. 20 parts by weight of compound No. 1.03
1 was thoroughly mixed with 3 parts by weight of sodium salt of diisobutyl-naphthalene-α-sulfonic acid, 17 parts by weight of sodium salt of ligninsulfonic acid from a sulfurous acid-waste solution and 60 parts by weight of powdered silica gel, and in a hammer mill. Grind at. By finely distributing this mixture in 20000 parts by weight of water, a spray liquid containing 0.1% by weight of the active substance is obtained.

V. 3 parts by weight of compound No. 1.031 is mixed with 97 parts by weight of finely divided kaolin. A dusting agent containing 3% by weight of the active substance is thus obtained.

VI. 20 parts by weight of compound No. 1.03
1 is intimately mixed with 2 parts by weight of calcium salt of dodecylbenzole sulfonic acid, 8 parts by weight of fatty alcohol polyglycol ether, 2 parts by weight of sodium salt of phenol-urea-formaldehyde-condensate and 68 parts by weight of paraffinic mineral oil. . A stable oily dispersion is obtained.

The herbicide or its active substance is applied by the pre-method or the post-method. If the active substance does not fit well into certain cultivated plants, it will stick to the growing weeds or exposed soil at the bottom, while affecting as little as possible the leaves of sensitive cultivated plants, It is possible to spray the herbicide with a spraying device (direct spraying, ray-by).

Amount of the active substance used as a herbicide [0124] The active substance per hectare (a.S) 0.01-
It is 5.0 kg, preferably 0.05-2.0 kg.

In view of the variety of application methods, the compounds I of the present invention or agents containing them can be used in various cultivated plants for controlling unwanted plants. For example, it is used for the following cultivated plants.

Onion (Allium cepa) Pineapple (Ananas comosos) Peanut (Arachis hypogaea) Asparagus (Asparagus officina)
lis) chard (Beta vulgaris spp.a)
L. tissima) Satojiya (Beta vulgaris spp.
Rapa) Brassica napus (Brassica napu)
s var. napus) Kabukanran (Variant napoplasica) (Brassic
a napus var. napobrassica) sugar beet (variety Sylvestris) (Brassica
rapa var. silvestris) Camellia sinensis safflower (Carthamus tinctoriu)
s) Carrya Illinoinensis
oinensis) Lemon (Citrus limon) Natsumikan (Citrus sinensis) Coffee [Coffea arabica (Coffe
a canephora, Coffea liberi
ca)] Cucumber (Cucumis sativus) Cynodon dactylon Carrot (Daucus carota) Oil palm (Elaeis guineutis guise) (Fragaria vesca hingeus Glyc) Soybean (Gly)
sypium arboreum, Gossypium
herbaceum, Gossypiumviti
folium)] sunflower (Helianthus annuus) rubber tree (Hevea brasiliensis) barley (Hordeum vulgare) Humulus lupulus (Humulus lupulus) American potatoes (Ipomoea batatas) Juglans (Juglans regia) lentils (Lens culinaris) flax (Linum usitatissimum) tomato (Lycopersicon lycopers
icum) Malus spp. Manihot esculenta Purple horse mackerel (Medicago sativ)
a) Tobacco (Musa spp.) Tobacco [Nicotiana tabacum (N.r.
(Ostica)] Olive (Olea europaea) Rice (Oryza sativa) Azuki (Phaseolus lunatus) Phagose cowpea (Phaseolus vulgari)
s) Spruce (Picea abies) Pinus (Pinus spp.) White pea (Pisum sativum) Sakura (Prunus avium) Prunus (Prunus persicainum Pyrus cousinus (Pyrus reticus) Spruce (Ribes reticus)
um) Rye (Secale cereal) Potato (Solanum tuberosum) Sorghum [Sorghum bicolor (s.vu
lgare)] cocoa (Theobroma cacao) Red clover (Trifolium platen)
se) Wheat (Triticum aestivum) Tritecum, drum (Triticum duru)
m) Vicia faba Grape (Vitis vinifera) Maize (Zea mays) Pyridine-2,3-carboxylic acid imide I is added to many other herbicides or plants in order to extend the effective range and to bring about a synergistic effect. It can be mixed with the growth control agent and applied together. For example, diamine, 4H-3,1-benzoxazine derivative, benzothiathiazinone, 2,6-nitroaniline, N-phenylcarbamate, thiocarbamate, halogencarboxylic acid, triazine, amide, and the like are used as a herbicidal mixture. Urea, diphenyl ether, triazinone, uracil, benzofuran derivative, cyclohexane-1,3-dione derivative, 2-
Examples thereof include a quinolinecarboxylic acid derivative having a carboxy group or a carbuimino group at the position, imidazoline, sulfonamide, sulfonylurea, aryloxy- or heteroaryloxy-phenoxypropionic acid, and salts, esters, amides and the like.

Furthermore, the compound I can be mixed alone or with other herbicides or plant growth regulators, as well as other plant protection agents, for example, plant and animal control agents, phytopathogenic fungicides and bactericides. Of interest is nutrition, which can also be mixed with salt solutions of mineral elements to combat rare element deficiencies. A wide variety of oils that are harmless to plants can also be added.

Preparation of precursor compound (a) 6-Chloro-5-methyl-pyridine-2,3-dicarboxylic acid diethyl ester 199.9 g (0.79 mol) of 5-methyl-pyridine-2,3-diethyl ester -N-oxide, 60
To 70 ° C. in portions over 1 hour into 1 liter of phosphoryl chloride and heated to reflux with stirring for 5 hours. After cooling to 25 ° C., the reaction mixture is concentrated under vacuum, the residue is taken up in methylene chloride and filtered by silica gel and concentrated to give 148.2 g of the title compound.
(69% of theory) was obtained as a yellow syrup,
It later solidifies. Melting point 84-86 [deg.] C.

[0129]

[Outside 1] (B) 6-Fluoro-5-methyl-pyridine-2,3-
Dicarboxylic acid diethyl ester 10 g (0.0368 mol) of the above compound (a) 15
Add to milliliter sulfolane and under stirring 3.2 g
(0.055 mol) potassium fluoride and 0.3 g
18-crown-6 was added thereto and stirred at 160 ° C. for 2 hours. After cooling to 25 ° C., 250 ml of water was added and extracted 3 times with methylene chloride.
After drying over magnesium sulfate and concentrating under vacuum, 8 g (85% of theory) of the title compound was obtained as a colorless oil.

[0130]

[Outside 2] 4-chloro-6-fluoro-5-methyl-pyridine-
2,3-dicarboxylic acid diethyl ester and 4,6-
Difluoro-5-methyl-pyridine-2,3-dicarbo
Acid diester (a) 15 g (0.049 mol) of 4,6-dichloro-
A mixture of 5-methyl-pyridine-2,3-dicarboxylic acid diethyl ester, 3.3 g (0.056 mol) of potassium fluoride and 0.25 g of 18-crown-6 is charged to 80 ml of sulfolane. ,
The mixture was stirred at 140 ° C for 5 hours (conversion rate 00%). After cooling
The reaction mixture was diluted with 200 ml of methyl-t-butyl ether and filtered off with suction with potassium salts. The filtrate was extracted 3 times with saturated aqueous sodium chloride solution, dried over magnesium sulfate and concentrated in vacuo to give 14.2 g of a yellowish oil. 3.55 g of the difluorine-substituted notation compound (boiling point 130-138 ° C / 0.5 mbar) by distillation
(27% of the theoretical amount) and 8.39 g of chlorine- and fluorine-substituted notation compound (boiling point 148-155 ° C / 0.5 mbar)
(53% of theory) was separated.

(B) Under similar reaction conditions, but 8.5
g (0.148 mol) of potassium fluoride, stirred at 160 ° C. for 14 hours, 7.21 g of difluoro compound (53% of theory) and 1.17 g of chlorofluoro compound (8.3 of theory). %) Was obtained.

5-Methoxy-pyridine-2,3-dical
8.3 g (1.05 mol) of boric acid diethyl ester in 250 ml of glacial acetic acid with stirring at 80 ° C. 221.
Add to 5 g (1.0 mol) of 2-amino-3-chloro-maleic acid diethyl ester, then 90 g (1.05 mol) of methoxyacrolene at 120 ° C. to bring about a gentle reflux without heating. After 30 minutes of stirring at 120 ° C., the reaction mixture was concentrated in vacuo, water was added to the residue and extracted with methylene chloride. Filtered through activated carbon, dried,
It was filtered off with suction with neutral aluminum oxide and concentrated under vacuum to give 190 g (75% of theory) of the title compound as a pale yellow syrup.

[0133]

[Outside 3] 6-Fluoro-pyridine-2,3-dicarboxylic anhydride 36.7 g (0.2 mol) of 6-chloro-pyridine-
A mixture of 2,3-dicarboxylic anhydride, 17.4 g (0.3 mol) potassium fluoride and 1 g 18-crown-6 was stirred under reflux in 200 ml propionitrile for 10 hours. . After cooling, the reaction mixture is filtered off with suction, washed with methylene chloride and the filtrate is concentrated in vacuo. This was stirred with a mixed solvent of methyl-t-butyl ether / pentane (2: 1), filtered off with suction and dried to give 25.3 g (76% of theory) of the title compound with a melting point of 106 ° C. (cenoum). .

Preparation of Compound I 1.5 -Chloro-6-methyl-pyridine-2,3-dica
Rubonic acid-Nt-butylimide (a) (5-amino-6-methyl-pyridine-2,3-
Dicarboxylic acid diethyl ester) 56.9 g (1.065 mol) of iron powder was added to 200 ml of glacial acetic acid and heated to 70 ° C. with stirring, and this was added to 100 g (0. Three
55 mol) 6-methyl-5-nitro-pyridine-2,
3-Dicarboxylic acid diethyl ester (European Patent Publication No. 227932) was added to the solution over 20 minutes. After stirring for 2 hours, 25.2 g (0.45 mol) of iron powder was further added in 200 ml of glacial acetic acid, the precipitated precipitate was filtered off with suction, the filtrate was concentrated under vacuum, and the residue was methylene chloride. I put it in. It was extracted successively with water, saturated sodium hydrogen carbonate solution and brine solution, dried over magnesium sulphate and filtered off with suction on silica gel in a suction funnel. From the third and fourth fractions, concentration gave 49 g of the title compound (55% of theory) as a yellow resin.

[0135]

[Outside 4] (B) (5-chloro-6-methyl-pyridine-2,3-
Dicarboxylic acid diethyl ester) 5.8 g (0.2 mol) of the above compound (a) at 20 ° C.
While stirring in 200 ml of concentrated hydrochloric acid was added little by little and cooled to 0 ° C., 31.7 g (0.46 mol) of sodium nitrite solution prepared by dissolving this solution in 60 ml of water was added. , 0 ° C. to 5 ° C. over 30 minutes and stirred for a further 30 minutes. 29.6 of the resulting dispersion in a Becher glassware.
g (0.5 mol) sodium chloride, 63.2 g (0.
25 mol) copper sulphate-5-hydrate and 120 ml water with stirring at 25 ° C. for 2 hours. This was extracted with methylene chloride, washed successively with saturated sodium hydrogen carbonate solution and brine solution, dried over magnesium sulphate, filtered off with suction through silica gel in a funnel and concentrated to 44.2 g (theoretical amount). 71%) of the title compound (n _D ²³ = 1.5150) was obtained.

(C) (5-Chloro-6-methyl-pyridine-2,3-dicarboxylic acid anhydride) 9.5 g (0.038 mol) of the above compound (b) was added,
3.02 g (0.075 mol) of sodium hydroxide, 2
The mixture was heated under reflux for 2 hours in a mixed solution consisting of 0 ml of water and 5 ml of ethanol. After cooling, the dicarboxylic acid salt was precipitated with 500 ml of acetone. Yield 9.18 (theoretical 93
%), Melting point> 240 ° C.> 9 g (0.035 mol) of this product are added to 100 ml of 1,2-dichloroethane, to which 6.8 g
(0.09 mol) acetyl chloride was added dropwise,
Heated at reflux for 8 hours. After cooling, suction filtration and washing with methylene chloride, 5.8 g of the title compound (theoretical amount 85
%) Was obtained. Melting point 140-141 [deg.] C.

(B) (Final step) 9.9 g (0.05 mol) of the above compound (c) was added to 150 g.
It was put into milliliter of 1,2-dichloroethane, to which 4.0 g (0.06 mol) of t-butylamine was added dropwise, and the mixture was stirred at 70 ° C. for 3 hours. After cooling to 25 ℃,
150 ml of thionyl chloride and 150 ml of glacial acetic acid were added successively and the phases were separated. Wash, dry and concentrate as in (b) above, melting point 1
5-chloro-6-methyl-pyridine-at 14-115 ° C
10 g (79% of theory) of 2,3-dicarboxylic acid-Nt-butylimide (Compound No. 1.031) were obtained.

2. 5-fluoro-pyridine-2,3-di
Chloro-N-1- (cyclopropyl) -ethylimide 19.5 g (0.0778 mol) of 5-chloro-pyridine-2,3-dicarboxylic acid-N-1- (cyclopropyl) -ethylimide, 9.1 g ( 0.156 mol) potassium fluoride and 0.4 g of 18-crown-
6 and 50 milliliters of sulfolane were stirred at 180 ° C for 6 hours. After cooling, this was added dropwise to 500 ml of glacial acetic acid, and the precipitated precipitate was filtered off with suction and washed with water. The residue was poured into methylene chloride, stirred on activated carbon, dried over magnesium sulphate and filtered off with suction with neutral sodium oxide. Concentrate under vacuum, mp 95
1 at −98 ° C. for the title compound (Compound No. 1.041)
4.1 g (78% of theory) were obtained. 3. 5,6-difluoro-pyridine-2,3-cycloro
-N-1- (cyclopropyl) -ethylimide 7.2 g (0.027 mol) 6-chloro-fluoro-
Pyridine-2,3-dicarboxylic acid-N-1- (cyclopropyl) -ethylimide, 2.3 g (0.04 mol) of potassium fluoride, 0.1 g of 18-crown-6.
And a mixture of 50 ml sulfolane were stirred at 150 ° C. for 3 hours. After cooling, the mixture was treated in the same manner as in Example 2 above, and then filtered by suction with silica gel to give 4.8 g (theoretical amount of 71) of the title compound (compound number 1.046) having a melting point of 52-54 ° C. %).

In the same manner as in Examples 1 to 3 above, various novel pyridine-2,3-dicarboxylic acid imides shown in Table 1 below were obtained. In addition, new pyridine-2,3-dicarboxylic acid anhydrides and pyridine-2,3-dicarboxylic acid esters are listed in Tables 2 and 3 below.

Table 1

[0141]

[Chemical 38]

[0142]

[Table 17]

[0143]

[Table 18]

[0144]

[Table 19]

[0145]

[Table 20]

[0146]

[Table 21]

[0147]

[Table 22] Use Example The herbicidal effect of pyridine-2,3-dicarboxylic acid imide I is demonstrated by the following room temperature experiment.

[0148] A plastic flower pot filled with loam sandy soil containing about 3.0% mulch as a cultivation base was used as an experimental container, and seeds of test plants were sown by type.

In the pretreatment method, immediately after sowing, an aqueous suspension or emulsion of the active substance was applied by means of a sprayer. To promote germination and growth, each container was covered with a transparent plastic sheet until each plant grew. This results in a uniform germination of the test plants, unless they are hindered by the active substance.

In the case of the post-treatment method, the test plants were treated with an aqueous suspension or emulsion of the active substance only after the growth height of each test plant was 3 to 15 cm. The test plant is
Seed directly and grow in the same flowerpot, or grow seedlings first and transplant several days before treatment in experimental vessels. The amount of effective substance applied by the post-treatment method was 0.5 to 0.25 kg per hectare.

The test plants were 10 in the greenhouse depending on their type.
It was arranged separately in a -25 ° C band and a 20-35 ° C band. The experimental period was 2 to 4 weeks during which the growth of the test plants was controlled and their response to individual treatments was observed.

The following plants were used in the greenhouse experiments.

[0153]

[Table 23] The results (Tables I, II and III below) show that the herbicidal effect of the compound of the present invention is significantly superior to the comparative proportions A, B and C known from European Patent Application Publication No. 422456.

Table I 0.5 kg of active substance per hectare in greenhouse
Fig. 7 shows the weed control effect when the cultivar is used in the post-hoc method.

[0155]

[Table 24] Table II 0.5 kg of active substance per hectare in greenhouse
Fig. 7 shows the weed control effect when the cultivar is used in the post-hoc method.

[0156]

[Table 25] Table III 0.5 kg of active substance per hectare in greenhouse
And weed control effects of 0.25 kg by the posterior method are shown.

[0157]

[Table 26]

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Matthias, Gerber Germany, 67117, Rimburger Hof, Brandenburger, Strasse, 24 (72) Inventor Helmut, Walter Germany, 67283, Obrichheim, Greene Statta, Strasse, 82 (72) Inventor Karl-Otto, Westphallen Germany, 67346, Speyer, Mouthberg Veek, 58

Claims (18)

[Claims] 1. The following general formula I: And R ¹ is hydrogen, C ₁ -C ₄ alkoxy, up to three substituents, namely C ₁ -C ₄ alkoxy, C ₁ -C ₄ halogenalkoxy, C ₁ -C ₄ alkylthio, C ₁ -C ₄ halogen alkylthio, C ₁ -C ₄
Dialkylamino, C ₃ -C ₈ cycloalkyl, halogen optionally substituted C ₁ -C ₆ alkyl, following up to three substituents, namely C ₁ -C ₆ alkyl, C ₁ -C ₆ halogenalkyl , C ₁ -C ₄ alkoxy, C ₁ -C ₄ -haloalkoxy, halogen, optionally substituted with nitro C ₃ -C ₈ cycloalkyl, optionally C ₃ -C be substituted by halogen, up to three ₆
Alkenyl or C ₃ -C ₆ alkynyl, R ² , R ³ and R ⁴ may be the same or different from each other and are each hydrogen, halogen, cyano, up to 5 halogens and / or 2 Up to C ₁ -C ₄ alkoxy,
C ₁ -C ₄ -haloalkoxy, C ₁ -C ₄ alkylthio, C ₁ -C ₄ halogen alkylthio, C ₃ -C ₆ cycloalkyl, optionally C ₁ -C be substituted by cyano ₆
Alkyl, up to 3 substituents, C ₁ -C ₄ alkyl, C ₁ -C ₄ halogenalkyl, C ₁ -C ₄ alkoxy, C ₁ -C ₄ halogenalkoxy, C ₁ -C ₄ alkylthio, C ₁ -C
₄ halogen alkylthio, halogen, cyano, benzyl which may be substituted by nitro, C ₁ -C ₄ alkyl or halogen optionally substituted C ₃ -C be the ₈ cycloalkyl up to three, halogens up to three And / or one C ₁ -C ₃ alkoxy or phenyl, which additionally contains C ₁ -C ₄ alkyl, C ₁ -C ₄ halogenalkyl, C ₁ -C ₄ alkoxy, C ₁ -C ₄ halogenalkoxy, C _1-. C ₄ -alkylthio, C ₁ -C ₄ halogenalkylthio, halogen, cyano, C ₂ -C ₆ alkenyl, which may be mono- or tri-substituted with nitro) as a substituent, up to 3 halogens , C ₁ -C ₃ alkoxy and / or one phenyl (which further C ₁ -C ₄ alkyl, C ₁ -C ₄ -haloalkyl, C ₁ -C ₄ a Kokishi, C ₁ -C ₄ -haloalkoxy, C ₁ -C ₄ alkylthio, C ₁ -C ₄ haloalkyl thio, halogen,
C ₁ -C ₆ alkynyl, which may have mono- or tri-substitution with cyano or nitro as a substituent, and R ² , R ³ and R ⁴ are each a C ₁ -C ₄ alkoxy. , C ₁
-C ₄ alkylthio, C ₁ -C ₄ -haloalkoxy,
C ₁ -C ₄ halogen alkylthio, C ₂ -C ₅ alkenyloxy, C ₂ -C ₅ alkynyloxy, C ₁ -C ₄ alkylsulfinyl, C ₁ -C ₄ alkylsulfonyl,
C ₁ -C ₄ halogenalkylsulfonyl, C ₁ -C ₄ alkyl, C ₁ -C ₄ halogenalkyl, C
₁ -C ₄ alkoxy, C ₁ -C ₄ -haloalkoxy,
C ₁ -C ₄ alkylthio, C ₁ -C ₄ halogenalkylthio, phenoxy or phenylthio optionally mono- to tri-substituted by halogen, cyano or nitro, 1 or 2 heteroatoms, ie oxygen, sulfur or nitrogen A 5- or 6-membered heterocycle having 1 or 2 substituents, which may have C ₁ -C ₃ alkyl, halogen, C ₁ -C ₃ alkoxy, C ₂ -C ₄ alkoxycarbonyl. ring group or, following up to three substituents, namely C ₁ -C ₆ alkyl, C ₁ -C ₆ halogenalkyl, C ₁ -C ₆ alkoxy, C ₁ -C ₆ -haloalkoxy, C ₁ -C ₆ alkylthio , C ₁ -C ₆ halogen alkylthio, halogen,
Nitro means phenyl which may have cyano, (a) when R ² means fluorine, and R ³ and R ⁴ have the meanings described above, (b) R ³ is fluorine, chlorine, C ₁ -C ₃ alkoxy, C
_2- C ₅ alkenyloxy, C ₂ -C ₅ alkynyloxy, trifluoromethyl, cyano and R ² ,
When R ⁴ has the meanings given above, (c) R ⁴ is halogen, C ₁ -C ₃ alkoxy, C ₂
-C ₅ alkenyloxy, C ₂ -C ₅ alkynyloxy, and excluding 5-chloropyridine-2,3-dicarboxylic acid imide where R ² and R ³ have the meanings given above. A pyridine-2,3-dicarboxylic acid imide, or an environmentally acceptable salt thereof. 2. A compound represented by the general formula I according to claim ¹ , wherein R ¹ is hydrogen, C ₁ -C ₆ alkyl, C ₃ -C ₆
Alkenyl, C ₃ -C ₆ alkynyl, _1-C 1 -C ₂ alkyl-cyclopropyl-1- (cyclopropyl) -C ₁
—C ₃ alkyl, C ₃ -C ₆ cycloalkyl, R ² , R ³ and R ⁴ are each independently hydrogen, C ₁ -C ₄ alkyl (up to 5 halogens, independently of each other). Pyridine-2, which may be substituted with atoms), C ₁ -C ₄ alkoxy, halogen, cyano, the third group having the meaning stated in claim (1). 3-dicarboxylic acid imide. 3. Pyridine-2,3-represented by formula I in claim (1) or (2), characterized in that R ² and / or R ³ and / or R ⁴ represent fluorine.
Dicarboxylic acid imide. 4. A herbicide containing a pyridine-2,3-dicarboxylic acid imide represented by formula I or a salt thereof according to any one of claims 1 to 3 and a conventional carrier. 5. An undesired plant and / or its growth space is treated with a herbicidally effective amount of the pyridine-2,3-dicarboxylic acid imide of the formula I according to any one of claims (1) to (3). A method for controlling unfavorable plants, which is characterized in that 6. The following formula II: And pyridinedicarboxylic acid anhydride represented by the following formula and R ² to R ⁴ have the meanings defined in claim (1):
In a manner known per se in an inert organic solvent, the following formula III: By reacting with a primary amine represented by the following formula IV: The method for producing a pyridine derivative represented by the formula I in claim (1), characterized in that the pyridinedicarboxylic acid half amide of (1) is closed with a water-decomposing agent. 7. The following formula Ia: Wherein R ² to R ⁴ have the above-mentioned meanings, and at least one of these means fluorine, which is a method for producing a fluorine-substituted pyridine-2,3-dicarboxylic acid imide, comprising: Formula Ib And R ¹ to R ⁴ have the meanings given above, but at least one of R ² to R ⁴ means chlorine, the corresponding chlorine-substituted pyridine-2,3-dicarboxylic imide is fluorinated. A method comprising halogen exchange with potassium. 8. A method for producing a fluorine-substituted pyridine-2,3-dicarboxylic acid imide represented by formula Ia according to claim 7, wherein the chlorine-substituted derivative of formula Ib is added in the presence of an aliphatic sulfone. A process characterized by treatment with sulfurous acid or carbonic acid chloride and then subjecting the reaction mixture to a halogen exchange. 9. The following formula IIa: Wherein R ² to R ⁴ have the meanings given above, but at least one of these is fluorine, a process for the production of a fluorine-substituted pyridinedicarboxylic acid anhydride comprising the formula IIb 8] And pyridine dicarboxylic acid anhydride represented by the formula (1) and R ² to R ⁴ have the above-mentioned meanings, at least one of which means chlorine, by halogen exchange with potassium fluoride. 10. A method for producing a fluorine-substituted pyridinedicarboxylic acid anhydride represented by the formula IIa according to claim 9, wherein the pyridinedicarboxylic acid anhydride of the formula IIb is added in the presence of an aliphatic sulfone. A process which comprises treating with sulfurous acid or a chloride of carbonic acid and then subjecting the reaction mixture to halogen exchange. 11. A compound of formula IIa ′ below: And one of R ² , R ³ and R ⁴ represents fluorine, and the remaining groups are hydrogen, fluorine, chlorine, C ₁ -C ₃ alkyl, C ₁ -C ₃ alkoxy, trifluoromethoxy, Means chlorodifluoromethoxy, methylthio, trifluoromethylthio, chlorodifluoromethylthio or methylsulfonyl, but 5-fluoro- and 4,5,
Pyridine-2,3-dicarboxylic acid anhydride, excluding 6-trifluoro-pyridine-2,3-dicarboxylic acid anhydride. 12. A 6-fluoro-pyridine-2,3-dicarboxylic acid anhydride and a 5,6-difluoro-pyridine-2,3-dicarboxylic acid anhydride. 13. The following formula IIa ': And R ⁴ is hydrogen, R ³ is chlorine, and C ₁ -C ₃
Alkoxy, trifluoromethyl or cyano can be replaced by R ²
Means fluorine, chlorine, C ₁ -C ₃ alkyl, C ₁ -C ₃ alkoxy, trifluoromethoxy, chlorodifluoromethoxy, methylthio, trifluoromethylthio, chlorodifluoromethylthio or methylsulfonyl, or R ² and R ⁴ are Hydrogen, or chlorine,
R ³ is C ₁ -C ₃ alkoxy, trifluoromethyl, cyano, trifluoromethoxy, chlorodifluoromethoxy, methylthio, trifluoromethylthio, chlorodifluoromethylthio or methylsulfonyl, and R ² and R
Pyridine-2,3-, characterized in that when ⁴ means chlorine, R ³ additionally means methyl or chlorine.
Dicarboxylic acid anhydride. 14. The following formula Va: And R ² to R ⁴ have the meanings given above, but at least one of these represents fluorine and R ⁵ represents optionally substituted low-molecular-weight alkyl, alkenyl or alkynyl. A process for preparing a fluorine-substituted pyridine dicarboxylic acid ester, which comprises the following formula Vb: And R ² to R ⁵ have the above-mentioned meanings, and wherein at least one of R ² to R ⁴ means chlorine, the pyridine dicarboxylic acid ester is halogen-exchanged with potassium fluoride. how to. 15. A method for producing a fluorine-substituted pyridinedicarboxylic acid ester represented by the formula Va in claim 12, wherein the pyridinedicarboxylic acid ester of the formula Vb is:
A process which comprises treating with sulfurous acid or a chloride of carbonic acid in the presence of an aliphatic sulfone and then subjecting the reaction mixture to a halogen exchange. 16. The following formula Va ': And n is 1, 2 or 3, and R ⁵ is C ₁ -C
4,5 when it means ₄ alkyl, C ₃ -C ₅ alkenyl or C ₃ -C ₅ alkynyl, phenyl optionally substituted by halogen or C ₁ -C ₄ alkoxy.
-And / or 6-fluoro-pyridine-2,3-dicarboxylic acid dialkyl ester. 17. The following formula Va ″: And R ² , R ³ and R ⁴ represent fluorine and the remaining groups are hydrogen, chlorine, C ₁ -C ₃ alkyl, C ₁ -C ₃ alkoxy, trifluoromethoxy, chlorodifluoromethoxy and methylthio. Means trifluoromethylthio, chlorodifluoromethylthio or methylsulfonyl,
R ⁵ is C ₂ -C ₄ alkyl, C ₃ -C ₅ alkenyl, C ₃
Pyridine-2,3-dicarboxylic acid dialkyl ester in the case of meaning -C ₅ alkynyl, phenyl optionally substituted by halogen or C ₁ -C ₄ alkoxy. 18. The following formula Va ″ ″ And R ³ represents chlorine, methyl, C ₁ -C ₃ alkoxy or cyano, and R ² and R ⁴ represent chlorine, C ₁ -C ₃ alkyl, C ₁ -C ₃ alkoxy, methylthio or methylsulfonyl. And when R ³ means C ₁ -C ₃ alkoxy, then R ² and R ⁴ also represent hydrogen,
R ⁵ is C ₂ -C ₄ alkyl, C ₃ -C ₅ alkenyl, C
_3- C ₅ alkynyl, phenyl optionally substituted by halogen, or C ₁ -C ₄ alkoxy, but diethyl 4,5-dimethyl- and 5,6-dimethyl-pyridine-2,3-dicarboxylate Pyridine-2,3-dicarboxylic acid dialkyl ester, characterized in that the ester is excluded.