PL113829B1 - Process for preparing novel n-substituted halogen acetanilides - Google Patents

Description

The subject of the invention is a method for preparing new N-substituted haloacetanilides used as active substances in selective weed control agents. It is known that chloroacetanilides, for example 2,6-diethyl-N-methoxymethylchloroacetonilide and 2-ethyl-6-methyl -N-(r-methyl-2-methoxyethyl)-chloroacetanilide can be used as herbicides (US patent no. 3,442,945, German patent DOS no. 2,328,340). These compounds act mainly on grasses of the millet species, e.g. Digitaris, Echinochloa, Panicum and Setaria. Other grass weeds, e.g. Alopecurus myosuroides and Avena fatua, are only destroyed when using higher doses of the given active substances. However, higher doses cause significant damage. production of cultivated plants, e.g. sugar beet, soybean or corn, and therefore these substances cannot be used selectively in the mentioned crops. It was found that the new N-substituted halo-acetanilides of formula 1, in which R is optionally substituted with chlorine imidazolyl radical-1, X and Y denote the same or different alkyl radicals with 1-4 carbon atoms, Z denotes a halogen atom and n denotes the number 0, 1 or 2, and their acid addition salts and metal complex salts , having a strong herbicidal effect, especially selective herbicidal effect; 10 u 25 2 is obtained by the reaction of N-halomethylhaloacetanilides of the formula 2, in which X, Y, Z and n have the meanings given above and Helium means a halogen atom, especially chlorine or bromine, with heterocyclic compounds of the formula 3. where R has the meaning given above and M denotes a hydrogen atom or an alkali metal atom, optionally in the diluent medium and optionally in the presence of an acid acceptor and then reacted with an acid or metal salt. The new N obtained by the method according to the invention -substituted haloacetanilides act much more effectively on grass weeds, such as Alopecurus myosuroides, Avena fatus, than the known chloroacetanilides; 2,6-diethyl-N-methoxymethylchloroacetanilide and 2-ethyl-6-methyl-N-methyl-2'-methoxymethoxychloroacetanide, which are chemically and functionally similar compounds. N-halo-*methylhaloaceanilides are used as starting compounds represents the general formula 2. In this formula, X and Y represent the same or different, preferably straight or branched alkyl radicals with 1-4 carbon atoms. Z preferably represents halogen atoms, chlorine or bromine, and n has the above-mentioned meaning. For example, the following starting compounds of formula 2 are used. 2-methyl-N-chloromethylchloroacetanilide, 2-methyl-N-bromomethylbromoacetanilide, 2-ethyl-N-bromoethylbromoacetanilide, 2-ethyl-N-chloromethy - 113 829113 829 ylchloroacetanilide, 2-propyl-N-chloromethylchloroacetanilide, 2-isopropyl-N-chloromethylchloroacetanilide. 2-butyl-N-chloromethylchloroacetanilide, 2- -isobutyl-N-chloromethylchloroacetanilide, 2-1--s.-butyl-N-chloromethyl-chloroacetanilide, 2-5-III -s.-butyl-N-chiDromethylchloroacetanilide, 2 ,6-dimethyl-N-chloromethylchloroacetanilide, 2,6-dimethyl-N-chloromethylchloroacetanilide, 2,6-diethyl-N-bromomethylbromoacetanilide, 2,6-diethyl-N-bromoethylbromoacetanilide, 2-ethyl-10-6- methyl-N-chloromethyl chloroacetanilide, 2,6-di-isoproplo-N-chloromethyl chloroacetanilide, 2,6-di-QL. butyl-N-chloroethylchloroacetanilide, 2,3-dimethyl-N-chloromet: lochloroacetanilide, 2,4-dimethyl-N-chlpromethylchloroacetanilide, 2,5-15-dimethyl-N-chloromethylchloroacetanilide, 2-ethyl-3- methyl-N-chloromethylchloroacetanilide, 2-ethyl-4-methyl-N-chloromethylchloroacetanilide, 2-ethyl-5-methyl-N-chloromethylchloroacetanilide, 2,4,6-tr6jmethyl-N-chloromethylchloroacetanilide "2,3,5 - 2o-trimethyl-N-chloromethylchloroacetanilide, 2-ethyl-4,6-dimethyl - N - chloromethylchloroacetanilide, 2,6-diethyl-4-methyl - N - chloromethylchloroacetanilide, 216H3Wuizaprbpyl-4-methyl-N-chloromethyl - chloroacetanilide. N-halomethylhaloacetanilides of the formula (2) are known and can be prepared according to known methods (US Pat. Nos. 3,630,716 and 3,637,847). They are obtained, for example, by reactions of the appropriate anilines with paraformaldehyde in the presence of catalytic amounts of potassium hydroxide, then reactions of the thus obtained phenylazomethines with a halogenated acetyl halide, for example chloroacetyl chloride. N-halomethylhaloacetanilides of formula 2 can be prepared according to a new method consisting in the fact that known haloacetanilides of the formula 4, in which X, Y, Z and maldehyde and a halogenating agent, e.g. hydrohalogen or inorganic or oric acid, an acid halide and a water-binding agent, e.g. sodium sulfate, 4 g at a temperature of -10°C to 150°C, preferably 10-70°C, optionally in the inert medium of an organic solvent, for example toluene (Germany DOS Pat. Nos. 2,119,518 and 2,210,603). When using inorganic acid halides, such as thionyl chloride, the use of an acid acceptor can be dispensed with (preparation examples). The heterocyclic compounds used as starting materials are generally represented by formula 3, in which R is imidazolyl-(i), optionally substituted with chlorine. Heterocyclic compounds of formula 3 are generally known compounds in organic chemistry. In the method according to the invention, organic diluents can be used, such as ketones, e.g. ethyl ketone, especially methylisobutyl ketone, nitriles, e.g. propiohitrile, especially acetonitrile, ethers, e.g. tetrahydrofuran or dioxane , aliphatic and aromatic hydrocarbons, e.g. petroleum ether, benzene, toluene or xylene, halogenated hydrocarbons, e.g. methylene chlorides, carbon tetrachloride, chloroform k:b chlorobenzene, esters, e.g. ethyl ester and formamides, especially dimethylformamide. All commonly used inorganic and organic acid acceptors can be used as acid acceptors, preferably alkali metal carbonates, e.g. sodium carbonate, potassium carbonate and sodium bicarbonate, and also lower tertiary alkylamides, arylalkylamines, aromatic amines or cycloalkylamines, e.g. triethylamine, dime - tylbenzylamine, pyridine and diazobiocyclooctane. An excess of the compound of formula 3 can also be used for this purpose. The reactions are carried out in a wide temperature range. Generally, it is carried out at a temperature of 0-120°C, preferably 20-80°C. When carrying out the method according to the invention, 1-2 moles of the heterocyclic compound of formula 3 and 1 mole of the compound of formula 2 are preferably introduced. acid acceptor. In order to isolate the compounds of formula I, the reaction mixture is filtered, the filtrate is washed with water and the mixture is concentrated. The residue is optionally purified by fractional crystallization or distillation. According to a variant of the method, the post-reaction mixture is cooled to approximately 0°C, filtered and hydrogen chloride is passed through the filtrate at a temperature of -13°C to 5°C. The precipitated chlorinated algae are filtered off and washed with an organic liquid, for example with ethyl acetate and water. pH values of approximately 12 are separated in a mixture of an organic solvent, for example ethyl acetate and water. The organic phase is separated and the compounds of formula 1 are isolated in a known manner. To obtain addition salts of compounds of formula 1, all acids tolerated by the body can be used, preferably hydrohalic acids, e.g. hydrochloric and hydrobromic acids, especially hydrochloric acid. also phosphoric, nitric, sulfuric, mono- and di-carboxylic and hydroxycarboxylic acids, e.g. acetic acid, maleic acid, succinic acid, fumaric acid, tartaric acid, citric acid, salicylic acid, sorbic acid, lactic acid, and sulfonic acids, e.g. new and 1,5-naphthalene disulfonic acid. Salts of compounds of formula 1 are obtained in a simple, known manner, for example, the compound of formula 1 is dissolved in a suitable organic solvent and an acid is added, e.g. hydrochloric acid, then isolated by filtration and, optionally, cleanses. _ , •' . ? In order to obtain metal complex compounds of the formula I, salts of metals of the main groups II-IV and side groups I-rII and IVr*-VIII are preferably used, for example copper, zinc, manganese, magnesium, tin, iron and nickel. Salt anions may be anions of acids tolerated by the body. Preferably, these are hydrohalic acids, eg hydrochloric acid, hydrobromic acid, and more. phosphoric, nitric and sulfuric acids. Metal complex salts of compounds of formula I can be obtained in a known manner, for example, the metal salt can be dissolved in an alcohol, e.g. ethanol, and a compound of formula I can be introduced. The metal complex salt can be isolated in a known manner. 829 6 Then the organic phase is separated and washed twice with 0.5 l of sodium chloride solution each time; p6, dried over sodium sulfate and evaporated in vacuo. 2,6-diethyl--N-imidazolyl-(l)-methyl-chloroacetamilide is obtained in the form of a colorless oil of formula 5, which was characterized by nuclear resonance based on spectrographic analysis. "r - " ' In a similar manner, the compounds listed in the table are obtained. Example IV (procedure a) 45 g (1.5 mol) of 2,6-diethylchloroacetanilide in 1.5 liters of toluene are added to a solution of 225.7 g (1 mole). paraformaldehyde. Heated to 40°C and, while stirring, 179 g (1.5 mol) of thionyl chloride were added dropwise, with intense evolution of gas. Then filtered and the filtrate was concentrated under reduced pressure. After degassing the residue under high vacuum, 268.7 g (98% of theoretical yield) of 2-6-diethyl:N-chloromethylchloroacetanilide of formula 6 are obtained in the form of a colorless oil (procedure b). To the solution 225.7 g (1 mol) 2 45 g (1.5 mol) of 6-diethylchloroacetanilide are added to 1.5 liters of anhydrous toluene, paraformaldehyde and 100 g of anhydrous sodium sulfate. While stirring, heat it to 50°C and dry hydrogen chloride is passed into it. disappearance of the milky suspension of paraformaldehyde. Then another 100 ml of anhydrous sodium sulfate are added, stirred for one hour at 50°C and filtered. The filtrate is concentrated under reduced pressure. After degassing the residue, 263.2 g (96% of theoretical yield) are obtained. 6-diethylchloroacetanilide (formula 6) in the form of a colorless oil. According to example IV, the compounds given in table 2 are obtained. Table 2 Compounds of formula 2 Example 1 V ' 1 VI VII 1 viii 1 IX 1 X 1 XI XII XIII XIV XV XVI XVII X R-CWfi :i'*i-'.CH3 c2h5 3 : v . / CH3 C2H5 i-C3H7 C2H5 CH3 CH3 CH3 C(CH3)3 C2H5 CH3 Yn 6-i-C3H7 6-C2H5 4,6-(CH3)2 4,6-(CH3)2 4-CH3, 6-C2H5 — — 6-CH3 5-CH3 3-CH3 — 6-C2H5 6-C2H5 Z Cl Cl Cl Cl Cl Cl Cl Cl Cl Cl Cl Br Br Hal Cl Cl Cl Cl Cl Cl Cl Cl Cl Cl Cl Br Br Melting point or coefficient refraction of light not separated,,0\\V91 not separated not separated not separated 90 not separated 88 not separated 40 not separated not separated not separated | for example, filter off and optionally purify by recrystallization. : ..,-•.Preparation-examples.•Example I. To 274.3 g (1 mol) of 2,6-diethyl-N-chloromethylchloracetanilide in 250 ml of anhydrous ethyl acetate is added with stirring, the mixture 68 g (1 mol) of imiazole and 106 g (1.05 mol) of itriethylamine in 150 ml of anhydrous ethyl acetate, the temperature rising to 30°C. Stir for 1 hour at room temperature. 10 The reaction mixture is cooled to 0°C, filtered and the residue is washed with 10 ml of cold ethyl acetate. 50 g (1.4 mol) of dry hydrogen chloride are passed through the filtrate at a temperature of -10°C to 0°C. Then the precipitated hydroxides are filtered off and washed with 50 ml of cold ethyl acetate and 0.5 liters of an aqueous solution of sodium oxide in DC x with a pH of 12. Pr H khd II III X C2Hs C2H5. Table 1 Compounds with formula 1 Yn 6- CH3 6-C2H5 Z Cl Cl R 2,4,5-tri-chloro-imidazolyl-1 imida-zolyl-1 Melting point (°C) 158 oil Preparation of the starting product.7 113 829 8 Patent claim Method. preparation of N-haloacetanilides of the formula I, wherein R is an optionally substituted chlorine-1-irnidazolyl radical, X and Y are the same or different. alkyl radicals with 1-4 carbon atoms, Z denotes a halogen atom and n denotes the number 0, 1 or 2, and their acid addition salts and metal complex salts, characterized in that N-halomethylhaloacetanilides of formula 2. wherein X, Y, Z and .¦ n have the meanings given above. and Hal denotes a halogen atom, especially chlorine or bromine, which is reacted with heterocyclic compounds of formula 3 in which R is higher. given; meaning and M represents a hydrogen atom or a metal atom. alkaline, optionally in the presence of a diluent, and an acid acceptor and then optionally subjected to an addition reaction with an acid or metal salt. Hal CO- and CpH. CI-L-nH /* * y 2 \=N C2H5 CO-CH2-Cl FORMULA 2 FORMULA 5 R — M FORMULA 3 C2H5 CO-O^Ci FORMULA 6 OZGraph. Z.P. Dz-wó, z. 149 (90+15) 8.82 Price PLN 100 PL PL PL

Claims (1)

1. Patent claim Method. preparation of N-haloacetanilides of the formula I, wherein R is an optionally substituted chlorine-1-irnidazolyl radical, X and Y are the same or different. alkyl radicals with 1-4 carbon atoms, Z denotes a halogen atom and n denotes the number 0, 1 or 2, and their acid addition salts and metal complex salts, characterized in that N-halomethylhaloacetanilides of formula 2. wherein X, Y, Z and .¦ n have the meanings given above. and Hal denotes a halogen atom, especially chlorine or bromine, which is reacted with heterocyclic compounds of formula 3 in which R is higher. given; meaning and M represents a hydrogen atom or a metal atom. alkaline, optionally in the presence of a diluent, and an acid acceptor and then optionally subjected to an addition reaction with an acid or metal salt. X CH2- R Yn CO-CH--Z CO-CH2-2 FORMULA 1 FORMULA 4 Yn N / \ CH2- Hal CO- ciyz CpH. CI-L-nH /* * y 2 \=N C2H5 CO-CH2-Cl FORMULA 2 FORMULA 5 R — M FORMULA 3 C2H5 CO-O^Ci FORMULA 6 OZGraph. Z.P. Dz-wó, z. 149 (90+15) 8.82 Price PLN 100 PL PL PL