HALOACETAMIDE COMPOUNDS, PROCESS FOR PRODUCTION THEREOF, AND USE THEREOF AS HERBICIDE

Abstract: A haloacetamide compound of the following formula (I) wherein R₁ represents a substituted or unsubstituted C₆-C₁₄ aryl group or a substituted or unsubsti­ tuted C₃-C₈ heteroaryl group having one or two hetero atoms selected from the group consist­ ing of O, S and N, R₂ and R₃, independently from each other, represent a hydrogen atom, a C₁-C₆ alkyl group or a C₁-C₆ alkoxy group, or R₂ and R₃, taken together, represent a C₂-C₁₆ alkylene group, R₄ represents a substituted or unsubstituted C₁-C₁₂ alkyl group, a substituted or unsubsti­ tuted C₆-C₁₄ aryl group, a C₂-C₁₂ alkenyl group or a C₂-C₁₂ alkynyl group, and Y represents a halogen atom selected from the group consisting of Cl, Br and I; and its use as herbicide.

Description: This invention relates to haloacetamide com­ pounds not described in the prior known literature, a process for production thereof, and to their use as a herbicide. More specifically, this invention relates to a haloacetamide compound of the following formula (I) wherein R₁ represents a substituted or unsubstituted C₆-C₁₄ aryl group or a substituted or unsubstituted C₃-C₈ heteroaryl group having one or two hetero atoms selected from the group consisting of O, S and N, R₂ and R₃, independently from each other, represent a hydrogen atom, a C₁-C₆ alkyl group or a C₁-C₆ alkoxy group, or R₂ and R₃, taken together, represent a C₂-C₁₆ alkylene group, R₄ represents a substituted or unsubstituted C₁-C₁₂ alkyl group, a substituted or unsubsti­ tuted C₆-C₁₄ aryl group, a C₂-C₁₂ alkenyl group or a C₂-C₁₂ alkynyl group, and Y represents a halogen atom selected from the group consisting of Cl, Br and I. This invention also pertains a process for producing the compound of formula (I), a herbicidal composition comprising the compound of formula (I) as an active ingredient, and to a method of controlling the growth of undesired vegetation using the compound of forfmula (I). It has been known that N-(1-alkenyl)-chloroacet­ anilides of the following formula (A) re useful as a herbicide or a plant growth regulator (Japanese Laid-Open Patent Publication No. 947/1983 laid-open on January 6, 1983 corresponding to West German Patent Application P 3120990.4). In the formula:- R¹ represents a hydrogen atom or an alkyl group, R² represents a hydrogen atom, or an alkyl, alkoxy, alkoxyalkyl, hydroxyalkyl or benzyl group, R³ represents a hydrogen atom, or an alkyl, alkenyl, alkoxy, alkoxyalkyl, alkylcarbonyl, alkylcarboxylalkyl, alkoxycarbonyl or alkoxy­ carbonylalkyl group, provided that R¹ and R², taken together with a double bond C=C, may represent an optionally substituted mono- or poly-unsaturated ring which may contain a hetero atom and/or a carbonyl group, or R² and R³, taken together with the adjacent carbon atom, may represent an optionally sub­ stituted saturated or unsaturated ring which may contain a hetero atom, or R² and R³ both represent a group of the formula in which R⁶ represents a hydrogen atom or an alkyl group and R⁷ represents an alkyl or phenyl group, and X¹, X², and X³, independently from each other, represents a hydrogen or halogen atom or an alkyl group. When the known chloroacetamide compounds of formula (A) are used as a herbicide in concentrations sufficient to obtain a satisfactory herbicidal efficacy, they cause unnegligible phytotoxicity to crop plants. Their herbicidal use is therefore limited. The present inventors have extensively worked in order to develop herbicidal compounds which have a broad herbicidal spectrum against paddy weeds and upland farm weeds, exhibit a satisfactory herbicidal efficacy when applied in relatively low concentrations, and do not cause phytotoxicity to crops and plants or toxicity to warm-blooded animals including man, domestic animals and poultry. Their work has resulted in successful synthesis of the compounds of formula (I) which are not described in the known literature, and has led to the discovery that these compounds show herbicidal activity against paddy weeds and upland farm weeds with a broad herbicidal spectrum. Investigations of the present inventors have shown that the compounds of formula (I) show a satis­ factory herbicidal effect at relatively low rates of application, and can control the growth of undesired vegetation without causing toxicity to crops and plants and warm-blooded animals. It has also been found as a result of research work by the present inventors that for the exhibition of the improved herbicidal activity mentioned above, it is critical that R₁ in the basic skeleton specified in formula (I) should be a specific aryl or heteroaryl group unlike the known compounds of formula (A). It is an object of this invention therefore to provide novel haloacetamide compounds not described in the prior known literature which are useful, for example, for controlling the growth of undesired vegetation. Another object of this invention is to provide a process for producing these novel haloacetamide com­ pounds, the use of these compounds as a herbicide, and a method of conrolling the growth of undesired vegetation using these compounds. The above and other objects of this invention along with its advantages will become more apparent from the following description. The novel haloacetamide compounds of this invention are represented by the following formula (I). In formula (I), R₁ represents a substituted or unsubstituted C₆-C₁₄ aryl group or a substituted or unsubstituted C₃-C₈ heteroaryl group having one or two hetero atoms selected from the group consisting of O, S and N. Examples of the aryl group for R₁ are phenyl, naphthyl, anthranyl and phenanthrenyl groups. The phenyl or naphthyl group is preferred. Examples of the hetero­ aryl group are furyl, thienyl, pyrrolyl, benzofuryl, benzothienyl, indolyl, thiazolyl, pyrazolyl, imidazolyl and pyridyl goups. The 5-membered heteroaryl groups and 5-membered heteroaryl groups having a fused carbon ring are preferred. The aryl or heteroaryl group represented by R₁ may have a substituent. Examples of the substituent include C₁-C₆ alkyl groups, halogen atoms, C₁-C₆ alkoxy groups, C₁-C₆ haloalkyl groups, C₁-C₆ alkylthio groups, a phenoxy group, substituted phenoxy groups having a substituent selected from C₁-C₆ alkyl groups and halogen atoms (Cl, Br, I and F), a phenyl group, and substituted phenyl groups having a substituent selected from C₁-C₆ alkyl groups and halogen atoms (Cl, Br, I and F). Examples of the substituent C₁-C₆ alkyl group mentioned above are methyl, ethyl, n- or iso-propyl, n- iso- or tert-butyl, n-pentyl, and n-hexyl groups. Examples of the substituent halogen atom above are Cl, Br, I and F. Examples of the substituent C₁-C₆ alkoxy group above are methoxy, ethoxy, n- or iso-propoxy, n-, iso- or tert-butoxy, pentyloxy and hexyloxy groups. Examples of the C₁-C₆ alkyl group which the substituted phenoxy or phenyl group may have are the same as those given for the substituent C₁-C₆ alkyl group above. Specific examples of the aryl groups for R₁ substituted by such substituents include alkylphenyl groups such as methylphenyl, dimethylphenyl, ethylphenyl, diethylphenyl, propylphenyl, dipropylphenyl, butylphenyl, pentylphenyl, hexylphenyl, methylethylphenyl, methylpro­ pylphenyl and ethylpropylphenyl groups; halophenyl groups such as fluorophenyl, difluorophenyl, chlorophenyl, dichlorophenyl, bromophenyl, iodophenyl, trichlorophenyl and chlorofluorophenyl groups; alkoxyphenyl groups such as methoxyphenyl, dimethoxyphenyl, trimethoxyphenyl, ethoxyphenyl, diethoxyphenyl, propoxyphenyl and butoxy­ phenyl groups; (haloalkyl)phenyl groups such as (chloro­ methyl)phenyl, (chloroethyl)phenyl, (chloropropyl)phenyl, (bromopropyl)phenyl, (fluoroethyl)phenyl, (difluoro­ methyl)phenyl, (trifluoromethyl)phenyl and (difluoro­ bromomethyl)phenyl groups; alkylthiophenyl groups such as methylthiophenyl, ethylthiophenyl, propylthiophenyl and butylthiophenyl groups; phenoxyphenyl groups such as phenoxyphenyl, (methylphenoxy)phenyl, (ethylphenoxy) phenyl, (butylphenoxy)phenyl, (chlorophenoxy)phenyl, (bromophenoxy)phenyl, (fluorophenoxy)phenyl and (chloro­ methylphenoxy)phenyl groups; phenylphenyl groups such as (methylphenyl)phenyl, (ethylphenyl)phenyl, (propyl­ phenyl)phenyl, (chlorophenyl)phenyl, (bromohenyl)phenyl, (fluorophenyl)phenyl and (iodophenyl)phenyl groups; substitutd phenyl groups such as chloro(methyl)phenyl, chloro(ethoxy)phenyl and methyl(methoxy)phenyl groups; and other substituted aryl groups such as methylnaphthyl, dimethylnaphthyl, ethylnaphthyl, chloronaphthyl, bromo­ naphthyl, dichloronaphthyl, methoxynaphthyl, (trifluoro­ methyl)naphthyl, methylthionaphthyl, phenoxynaphthyl, chlorophenoxynaphthyl, methylphenoxynaphthyl, phenyl­ naphthyl, chlorophenylnaphthyl, methylanthranyl, ethyl­ anthranyl, chloroanthranyl, bromoanthranyl, methoxy­ anthranyl, methylthioanthranyl, phenoxyanthranyl, phenyl­ anthranyl, methylphenanthryl, chlorophenanthryl, ethoxy­ phenanthryl and ethylthiophenanthryl. Specific examples of the heteroaryl group for R₁ substituted by the above-illustrated substituents include substituted furyl groups such as methylfuryl, dimethylfuryl, ethylfuryl, propylfuryl, chlorofuryl, bromofuryl, methoxyfuryl, ethoxyfuryl, propoxyfuryl, (trifluoromethyl)furyl, methylthiofuryl, ethylthiofuryl, phenoxyfuryl, (chlorophenoxy)furyl, phenylfuryl and methylphenylfuryl groups; substituted thienyl groups such as methylthienyl, ethylthienyl, propylthienyl, butyl­ thienyl, fluorothienyl, chlorothienyl, bromothienyl, iodothienyl, methoxythienyl, ethoxythienyl, propoxy­ thienyl, (chloroethyl)thienyl, (trifluoromethyl)thienyl, methylthiothienyl, ethylthiothienyl, dibromothienyl, dimethoxythienyl, phenoxythienyl, (methylphenoxy)thienyl and chlorophenylthienyl groups; substituted pyrrolyl groups such as N-methylpyrrolyl, N-ethylpyrrolyl, methyl-N-methylpyrrolyl, chloro-N-ethylpyrrolyl, methoxy-N-methylpyrrolyl, (trifluoromethyl)-N-methyl­ pyrrolyl, methylthio-N-ethylpyrrolyl, phenoxy-N-methyl­ pyrrolyl and phenyl-N-ethylpyrrolyl groups; substituted benzofuryl groups such as methylbenzofuryl, chlorobenzo furyl, ethoxybenzofuryl, (trifluoromethyl)benzofuryl and phenoxybenzofuryl groups; substituted benzothienyl groups such as ethylbenzothienyl, fluorobenzothienyl, methoxy­ benzothienyl, methylthiobenzothienyl and phenylbenzo­ thienyl groups; a methylthiazolyl group; substituted pyrazolyl groups such as dimethylpyrazolyl and phenyl­ pyrazolyl groups; and substituted imidazolyl groups such as methoxyimidazolyl and phenylimidazolyl groups. In formula (I) in this invention, R₂ and R₃, independently from each other, represent a hydrogen atom, a C₁-C₆ alkyl group or a C₁-C₆ alkoxy group, or R₂ and R₃, taken together, represent a C₂-C₁₆ alkylene group in which case R₂ and R₃ form a cycloalkylene group having 3 to 17 carbon atoms including the carbon atom to which they are bonded. The C₁-C₆ alkyl group includes linear or branched alkyl groups having 1 to 6 carbon atoms, and specific examples are methyl, ethyl, n-propyl, iso-­ propyl, n-butyl, iso-butyl, n-pentyl an n-hexyl groups. Specific examples of the C₁-C₆ alkoxy group are methoxy, ethoxy, propoxy, butoxy, pentyloxy and hexyloxyl groups. Examples of the alkylene group having 2 to 16 carbon atoms which may be formed by linking of R₂ and R₃ are ethylene, trimethylene, tetramethylene, penta­ methylene, hexamethylene, heptamethylene, octamethylene, decamethylene and undecamethylene groups. In the compound of formula (I) in accordance with this invention, R₄ represents a substituted or un­ substituted C₁-C₁₂ alkyl group, a substituted or unsub­ stituted C₆-C₁₄ aryl group, a C₂-C₁₂ alkenyl group or a C₂-C₁₂ alkynyl group. The C₁-C₁₂ alkyl group includes linear or branched alkyl groups, and specific examples include, methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl and dodecyl groups. Examples of the C₆-C₁₄ aryl group include phenyl naphthyl, anthranyl and phenanthrenyl groups. The phenyl or naphthyl group is preferred. Examples of the C₂-C₁₂ alkenyl group include ethenyl, propenyl, butenyl, pentenyl, hexenyl, heptenyl, octenyl, decenyl and dodecenyl groups. The C₂-C₆ alkenyl groups are preferred. Examples of the C₂-C₁₂ alkynyl group include ethynyl, propynyl, butynyl, pentynyl, hexynyl, heptynyl, octynyl, decynyl and dodecynyl groups. The C₂-C₆ alkynyl groups are preferred. The C₁-C₁₂ alkyl group for R₄ may be substi­ tuted by substituents. Examples of the substituents for the alkyl group R₄ include halogen atoms; C₁-C₆ alkoxy groups; C₁-C₆ alkylthio groups; a phenoxy group; substi­ tuted phenoxy groups having a substituent selected from C₁-C₆ alkyl groups, C₁-C₆ alkoxy groups, C₁-C₆ alkylthio groups and halogen atoms; a cyano group; a phenyl group; substituted phenyl groups having substituent selected from C₁-C₆ alkyl groups, C₁-C₆ alkoxy groups, C₁-C₆ alkylthio groups and halogen atoms; C₃-C₅ heteroaryl groups having one or two hetero atoms selected from O, S and N which are unsubstituted or substituted by a substituent selected from C₁-C₆ alkyl groups and halogen atoms; C₂-C₆ hetero­ cycloalkyl groups having one or two hetero atoms selected from O, S and N which are unsubstituted or substituted by C₁-C₆ alkyl groups; alkoxycarbonyl groups having 1 to 6 carbon atoms in the alkoxy moiety; alkylcarbonyloxy groups having 1 to 6 carbon atoms in the alkyl moiety, which may optionally be substituted by halogen atoms; C₂-C₆ alkenyloxy groups and C₂-C₆ alkynyl groups. With regard to the substituents on the alkyl group R₄, examples of the halogen atoms are Cl, Br, I and F, and examples of the C₁-C₆ alkoxy groups are methoxy, ethoxy, n-propoxy, iso-propoxy, n-butoxy, iso-­ butoxy, n-pentyloxy, and n-hexyloxy groups. Examples of the C₁-C₆ alkylthio groups are methylthio, ethylthio, n- or iso-propylthio, n- or iso-butylthio, pentylthio and hexylthio groups. Examples of the C₁-C₆ alkyl group for the phenoxy group are methyl, ethyl, n- or iso-propyl, n- or iso-butyl, pentyl and hexyl groups. Examples of the C₁-C₆ alkoxy and C₁-C₆ alkylthio groups and halogen atoms as the substituents for the phenoxy group may be the same as those given hereinabove. Examples of the substituents for the phenyl group may be the same as the substituents cited above as examples of the substituents for the phenoxy group. Furthermore, examples of the C₁-C₆ alkyl groups and halogen atoms as susbstituents for the C₃-C₅ heteroaryl group may be the same alkyl groups and halogen atoms as given above. Examples of the C₃-C₅ heteroaryl group may be those heteroaryl groups having 3 to 5 carbon atoms exemplified with regard to the heteroaryl group for R₁. Examples of the C₂-C₆ heterocycloalkyl group which the substituents for the alkyl group R₄ may have include tetrahydrofuryl, tetrahydrothienyl, pyrrolidyl, tetra­ hydropyryl, tetrahydrothiopyryl and piperidyl groups. Examples of the C₁-C₆ alkyl substituent which these heterocycloalkyl groups may have are the same C₁-C₆ alkyl groups given above with regard to the substituents for the phenoxy group. Examples of the alkoxycarbonyl groups having 1 to 6 carbon atoms in the alkoxy moiety are methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, butoxy­ carbonyl and pentoxycarbonyl groups. Examples of the alkylcarbonyloxy groups having a C₁-C₆ alkyl group optionally substituted by a halogen atom are methyl­ carbonyloxy, ethylcarbonyloxy, propylcarbonyloxy, butylcarbonyloxy, pentylcarbonyloxy, (chloromethyl)­ carbonyloxy, (bromoethyl)carbonyloxy, (fluoropropyl)­ carbonyloxy, (dichloropropyl)carbonyloxy and (trifluorobutyl)carbonyloxy groups. Examples of the C₂-C₆ alkenyloxy groups are ethenyloxy, propenyloxy, butenyloxy, pentenyloxy and hexenyloxy groups. Examples of the C₂-C₆ alkynyloxy groups are ethynyloxy, propynyl­ oxy, butynyloxy, pentynyloxy and hexynyloxy groups. In the compounds of formula (I) in accordance with this invention, the C₆-C₁₄ aryl group for R₄ may have a substituent. Examples of the substituents are halogen atoms, C₁-C₆ alkyl groups which are unsubstituted or substituted by halogen atoms, C₁-C₆ alkylthio groups and C₁-C₆ alkoxy groups. Examples of the halogen atoms are Cl, Br, I and F. Examples of the C₁-C₆ alkyl groups are methyl, ethyl, n- or iso-propyl, n- or iso-butyl, pentyl and hexyl groups. Examples of the halogen atoms which the alkyl group may have are Cl, Br, I and F. Specific examples of the substituted C₁-C₁₂ alkyl group for R₄ include linear or branched haloalkyl groups such as fluoromethyl, trifluoromethyl, chloro­ methyl, trichloromethyl, chloroethyl, bromoethyl, fluoro­ propyl, chloropropyl, chlorobutyl, bromopentyl and chloro­ hexyl groups; linear or branched alkoxyalkyl groups such as methoxymethyl, methoxyethyl, dimethoxyethyl, methoxy­ propyl, methoxybutyl, methoxypentyl, methoxyhexyl, ethoxy­ methyl, ethoxyethyl, diethoxyethyl, ethoxypropyl, di­ ethoxypropyl, ethoxybutyl, propoxymethyl, propoxyethyl, propoxypropyl, propoxybutyl, butoxymethyl, butoxyethyl, butoxypropyl, butoxybutyl and pentoxyethyl groups; phenoxyalkyl groups such as phenoxymethyl, phenoxyethyl, (methylthiophenoxy)methyl, (bromophenoxy)ethyl, (chloro­ phenoxy)ethyl, (methylphenoxy)ethyl, (propoxyphenoxy)­ ethyl and (chlorophenoxy)propyl groups; cyanoalkyl groups such as cyanoethyl, cyanopropyl and cyanobutyl groups; alkylthioalkyl groups such as methylthiomethyl, methyl­ thioethyl, methylthiopropyl, ethylthiomethyl, ethylthio­ ethyl, ethylthiobutyl and propylthioethyl groups; phenyl­ alkyl groups such as phenylmethyl, phenylethyl, phenyl­ propyl, (ethylthiophenyl)methyl and (chlorophenyl)propyl groups; heteroarylalkyl groups such as thienylmethyl, thienylethyl, methoxythienylmethyl, furylmethyl, furyl­ ethyl, chlorofurylmethyl, pyrrolylmethyl, pyrrolylethyl, pyrazolylmethyl, pyrazolylethyl and imidazolylethyl; heterocycloalkylalkyl groups such as tetrahydrofuryl­ methyl, tetrahydrofurylethyl, methyltetrahydrofurylethyl, pyrrolidyl ethyl, piperidylethyl, N-methylpyrrolidyl­ ethyl, N-methylpyrrolidylmethyl, methylpiperidylpropyl, tetrahydrothienylmethyl and tetrahydrothienylethyl groups; alkoxycarbonylalkyl groups such as methoxy­ carbonylmethyl, methoxycarbonylethyl, ethoxycarbonyl­ methyl, ethoxycarbonylethyl, propoxycarbonylethyl, ethoxycarbonylpropyl and butoxycarbonylpropyl groups; alkylcarbonyloxyalkyl groups such as methylcarbonyloxy­ methyl, methylcarbonyloxyethyl, methylcarbonyloxypropyl, ethylcarbonyloxymethyl, ethylcarbonyloxyethyl, ethyl­ carbonyloxypropyl, propylcarbonyloxyethyl, (chloromethyl)­ carbonyloxymethyl, (chloromethyl)carbonyloxyethyl, (chloroethyl)carbonyloxyethyl and (fluoroethyl)carbonyl­ oxyethyl groups; alkenyloxyalkyl groups such as ethenyl­ oxymethyl, ethenyloxyethyl, propenyloxymethyl, propenyl­ oxyethyl, propenyloxypropyl, propenyloxybutyl, butenyl­ oxyethyl, and butenyloxypropyl; and alkynyloxyalkyl groups such as ethynyloxymethyl, ethynyloxyethyl, pro­ pynyloxymethyl, propynyloxyethyl, propynyloxypropyl, propynyloxybutyl and butynyloxyethyl groups. In general formula (I), Y is a halogen atom selected from chlorine, bromine and iodine atoms. Y is preferably a chlorine or bromine atom. Compounds of formula (I) having the groups specifically exmplified hereinabove, in many cases, include various position isomers. Such isomers may be utilized in this invention without any particular re­ striction. For example, the methylphenyl group includes o-methylphenyl, m-methylphenyl and p-methylphenyl, and the butyl group includes n-butyl, sec-butyl, and tert-­ butyl. The structure of the compound of general formula (I) in accordance with this invention can be determined by the following procedures. (A) By measuring the infrared absorption spectrum (ir) of the compound, an absorption near 3200 - 2800 cm⁻¹ assigned to the CH bond, a strong absorption near 1680 - 1670 cm⁻¹ assigned to the carbonyl linkage of the amide group, and a weak absorption near 1640-1620 cm⁻¹ assigned to the C=C bond can be observed. (B) The mass spectrum (ms) of the compound is measured, and the composition formula corresponding to the individual peaks observed (generally the mass number m/e obtained by dividing the ion molecular weight m by the ion charge number e). This gives information on the molecular weight of the compound and the manner of bond­ ing the atomic groupings in the molecule. When the compound is represented by the following general formula the molecular ion peaks (to be abbreviated M ⊕ ) are generally observed by the intensity ratio in accordance with the ratio of existing isotopes according to the number of halogen atoms contained in the molecule, and therefore, the molecular weight of the compound can be determined. In the compound of general formula (I), characteristic peaks corresponding to M ⊕ -Y and M ⊕ -COCH₂Y are observed, and the manner of bonding of the molecules can be known. (C) By measuring the ¹H-nuclear magnetic resonance spectrum (¹H-nmr), the manner of bonding of hydrogen atoms present in the compound can be determined. As a typical example of the ¹H-nmr (δ, ppm: tetramethyl­ silane as an internal standard, deuterochloroform as a solvent) of the compound of general formula (I), the ¹H-nmr chart of N-[1-(phenyl)ethenyl]-N-chloroaceto-­ 2',6'-dimethylanilide is shown in Figure 2. The results of its analysis are as follows:- A singlet corresponding to 6 protons based on the methyl group (d) is observed at 230 ppm; a singlet corresponding to 2 protons based on the chloroacetyl group (c), at 3.75 ppm; two singlets corresponding to 1 proton based on the ethenyl groups (a) and (b), at 4.41 ppm and 4.97 ppm; and a multiplet corresponding to 8 protons based on the benzene ring, at 7.10 ppm to 7.60 ppm. (D) The weight percents of carbon, hydrogen, nitrogen and halogen (sulfur as well when the compound contains it) are determined by elemental analysis. By subtracting the total of the recognized weight percents of the individual elements from 100, the weight percent of oxygen can be calculated. Accordingly, the com­ position formula of the compound can be determined. The haloacetamide compounds of this invention differ somewhat in properties depending upon the types of R₁, R₂, R₃, R₄ and Y in general formula (I) and the degree of purification. Generally, they are pale yellow to blackish brown viscous liquids or solids at ordinary temperature and atmospheric pressure. Specific properties will be shown in Examples. The compounds of this invention are soluble in general organic solvents such as benzene, ethers, alcohols, chloroform, aceto­ nitrile, dimethylformamide and dimethylsulfoxide, but are only sparingly soluble in water. According to this invention, various novel haloacetamide compounds can be provided by selecting R₁, R₂, R₃, R₄ and Y in general formula (I). Specific examples of typical compounds of general formula (I) are shown below. The compounds of general formula (I) may be produced typically by the following processes, for ex­ ample. (i) A process for producing the compound of general formula (I), which comprises reacting a Schiff base compound represented by the general formula wherein R₁, R₂, R₃ and R₄ are as defined above, with a haloacetyl halogenide represented by the general formula YCH₂COX wherein Y represents Cl, Br or I, and X re­ presents Cl, Br, I or F. The starting Schiff base compound of general formula (III) may be those which are prepared by any methods. For example, they can be obtained by dehydro­ condensing the corresponding carbonyl compounds with amine compounds in accordance with the following reaction scheme. The mole ratio of the Schiff base compound of general formula (II) and the haloacetyl halogenide in the above reaction may be properly determined as required. For example, the haloacetyl halogenide is used generally in an equimolar proportion or a slightly excessive molar proportion. Since hydrogen halide forms as a by-product in the above reaction, it is preferred to carry out the reaction usually in the copresence of a hydrogen halide scavenger. The scavenger may, for example, be triethyl­ amine, tripropylamine, pyridine, sodium alcoholates or sodium carbonate. In the above reaction, the use of an organic solvent is generally preferred. Examples of suitable organic solvents used in this reaction include benzene, toluene, xylene, hexane, petroleum ether, chloroform, methylene chloride, ethyl ether, dioxane, tetrahydro­ furan, acetone, methyl ethyl ketone, acetonitrile, N,N-­ dimethylformamide, hexamethylphosphoramide and dimethyl sulfoxide. The use of a basic polar solvent such as N,N-­ dimethylformamide, N,N-dimethylacetamide or hexamethyl­ phosphoramide as the solvent for the reaction is prefer­ red since in many cases, the reaction in such a solvent proceeds easily without the presence of a scavenger for the by-product hydrogen halide, and the final haloacet­ amide compound can be obtained in high yields. The sequence of adding the starting materials in the above reaction is not particularly limited. For example, the Schiff base compound of general formula (II) is dissolved in a solvent, and the haloacetyl halogenide is added to the solution with stirring. The reaction temperature may be selected from a broad range, and is, for example, -20 to 150°C, prefer­ ably -10 to 120°C. The reaction time varies depending upon the types of the starting materials and the reaction temperature. For example, it is 5 minutes to 10 days, preferably 1 hour to 50 hours. Preferably, the reaction is carried out with stirring. There is no particular limitation on the method of isolating the final compound of general formula (I) from the reaction mixture and purifying it, and any known methods can be used. For example, the final compound can be obtained by distilling off the reaction solvent and the hydrogen halide scavenger after the reaction, adding water to the residue, extracting the mixture with an extracting organic solvent such as benzene, ether or chloroform, drying the organic layer with a desiccant such as sodium sulfate or calcium chloride, distilling off the solvent, and vacuum distilling the residue. Purification can also be carried out by chromatography, recrystallization, etc. The use of an amide-type polar solvent such as N,N-dimethylformamide as the reaction solvent often obviates the need for the hydrogen halide scavenger. After the reaction, low-boiling materials are distilled off, and then by simply vacuum-distilling the residue, the final compound can be obtained. Alternatively, after the reaction, water is added to the reaction mixture, and the mixture is extracted with an extracting organic solvent such as benzene, ether or chloroform. The organic layer is dried with a desiccant such as sodium sulfate. The solvent is distilled off, and the residue is purified by vacuum distillation chromatography, or recrystallization to obtain the final compound. (ii) The haloacetamide compound of general formula (I) can also be produced by a process which comprises reacting a Schiff base compound represented by the general formula wherein R₁, R₂ and R₃ are as defined above, and R₈ and R₉ are identical or different and each represents a hydrogen atom or is the same as R₄ except that the largest number of carbon atoms is less than that of R₄ by one, with a haloacetyl halogenide of the general formula YCH₂COX wherein Y and X are as defined hereinabove, in the presence or absence of a silane compound re­ presented by the following formula wherein X₄, X₅ and X₆ are identical or differ­ ent and each represents a hydrogen atom or a halogen atom. In the above reaction, the reaction temperature is, for example, 20 to 150°C, and the reaction time is 5 minutes to 10 days. As required, the reaction may be carried out in a suitable solvent same as the solvents illustrated with regard to the reaction (i), such as benzene, toluene, acetonitrile and chloroform. When the above reaction is used in the absence of the silane compound, it is preferred to carry out the reaction in the presence of a known hydrogen halide scavenger in the reaction system. (iii) The haloacetamide compound of general formula (I) can also be produced by a process which comprises reacting the Schiff base compound of general formula (III) above wilth a haloacetyl halogenide re­ presented by the general formula YCH₂COX wherein Y and X are as defined above, and threreafer reacting the product with a compound represented by the following formula A-R₁₀ wherein A represents a hydrogen atom, a lithium atom, a sodium atom, a potassium atom, a zinc atom, or a (trialkyl)silyl group having 1 to 4 carbon atoms, and R₁₀ is the same as the substituent in the substituted alkyl group for R₄. The use of an organic solvent is preferred in this re­ action. Examples of the organic solvent are benzene, toluene, hexane, methylene chloride, chloroform, aceto­ nitrile, ethyl ether, N,N-dimethylformamide and dimethyl sulfoxide. Where A in the above formula A-R₁₀ is a hydrogen atom, it is preferred to use a known hydrogen halide scavenger such as triethylamine, pyridine, sodium carbonate and potassium carbonate. In the above re­ action, it is preferred to employ a reaction temperature of, for example, -20 to 150°C and a reaction period of, for example, 5 minutes to 10 days. The compounds of general formula (I) provided by this invention exhibit an excellent efficacy as a herbicide, for example in pre-emergence and post-­ emergence soil treatment of gramineous weeds, broad-­ leaved weeds and perennial weeds. In particular, they exhibit a selective herbicidal effect when used as a herbicide for upland farms, and can therefore be applied to not only broad-leaved crops such as soybean, cotton and beet but also gramineous crops such as wheat, barley, corn and dry land rice. They also have excellent selec­ tive herbicidal activity on lawn. Compounds of general formula (I) which have a specific skeleton also exhibit a goods elective herbicidal effect against paddy weeds. By properly selecting R₁, R₂, R₃, R₄ and Y in general formula (I), the compounds of the present inven­ tion exhibit an excellent herbicidal effect as herbicides for upland farms, lawn and paddies. Examples of weeds to which the compounds of this invention can be applied with especially good results include upland farm weeds and lawn eeds such as large crabgrass ( Digitaria ciliaris Koeler), goosegrass ( Eleusine indica ), green foxtail ( Setaria viridis Beauvois), common lamb's quarters ( Chenopodium album L.), smartweed ( Polygonum longisetum De. Bruyn.), large smartweed (polygonum lapathifolium L. subsp. nodosum (Pers.) Kitam), yellow nutsedge ( Cyperus microiria Steud.), yellow cyperus ( Cyperus iria L.), pigweed ( Amaranthus lividus L.), common purslane ( Portulaca oleracea L.), red clover ( Trfifolium pratense L.), creeping woodsorrel ( Oxalis corniculata L.), water foxtail ( Alopecurus aequalis Sorol.), annual bluegrass ( Poa annua L.), bedstraw ( Galium spurium L.), blue morn ing glory ( Ipomoea indica Merrill), "kawaraketsumei" ( Cassia nomame Honda), common vetch (Vicia sativa L.), and shepherd's purse ( Capsella bursa - pastoris Medik.) hairy beggartics (Bidens pilosa); paddy weeds such as barnyard grass ( Echinochloa crus - galli Beauv.; Echinochloa oryzicola Vasing), umbrella plant ( Cyperus difformis L.), three-square grass ( Scirpus juncoides Rxb.), "mizugayatsuri" ( Cyperus serotinus Rottr.), "himekugu" ( Kyllinga brevifolia Rottr.), water chustnut ( Eleocharis kuroguwai Ohwi), slender spikerush ( Eleocharis acicularis , Roem. et Schult.), river bulrush ( Scirpus planiculmis Fr. Schm.), arrowhead ( Sagittaria trifolia L.), "aginashi" ( Sagittaria aginashi Makino), narrowleaf waterplantain ( Alisma canaliculatum , A. Bn. et Couche), "urikawwa" ( Sagittaria pygmaea Miq.), largeleaf pondweed ( Potamogeton distinctus A. Benn.), dropwort ( Oenanthe javanica de Candolle), monochoria ( Monochoria vaginalis Presl.), "ibokusa" ( Aneilema keisak Hand-­ Mazt.), water wort ( Elatine triandra Schk.), "himemisohagi" ( Ammannia multiflora Roxb.), false loosestrife ( Ludwigia prostrata Roxb.), "azemushiro" ( Lobelia chinensis Lour.), burmarigold ( Bidens tripartita L.), devil's beggarticks ( Bidens frondosa L.), "abunome" ( Dopatrium junceum Hamilt.), false pimpernel ( Lindernia pyxidaria L.), and "azetogarashi" ( Vandellia angustifolia Bentham). Those haloacetamide compounds of general formula (I) which have a particularly excellent herbicidal effect and can be easily produced industrially are, for example, those of general formula (I) in which R₁ is an unsubsti­ tuted phenyl group, or a phenyl group substituted by a C₁-C₆ alkyl group, a C₁-C₆ alkoxy group, or a phenoxy group; R₂ and R₃ each represent a hydrogen atom or a C₁-C₄ alkyl group; and R₄ is a C₁-C₆ alkyl group, a C₁-C₆ alkoxyalkyl group, or a phenyl group substituted by a C₁-C₄ alkyl group and/or a C₁-C₄ alkoxy group. Typical examples of the above compounds include the following. As a herbicide, the compound of general formula (I) exhibits a sufficient herbicidal efficacy when used at a rate of generally 2 to 3000 g/10 ares, preferably 10 to 1000 g/10 ares, more preferably 30 to 600 g/10 ares. The compound of general formula (I) is frequent­ ly used conveniently in admixture with a known herbicide such as phenoxy-type compounds, triazine-type compounds, amide-type compounds, pyrazolate-type compounds, sulfonyl­ urea-type compounds, etc. because the combined use permits a decrease in the amounts of the respective compounds and is moreover expected to produce a synergistic effect. Since the compounds of general formula (I) affect the growth of vegetation, they can also be used as a defoliant, a germination inhibitor and a growth regula­ tor. The mode of using the compounds of general formula (I) may be those in which known herbicides are used. For example, they may be formulated into suitable forms such as granules, a dust, an emulsifiable concen­ trate, a wettable powder, tablets, an oil, an aerosol or a fumigant by using agriculturally acceptable solid or liquid diluents or carriers. As required, agriculturally acceptable adjuvants such as stickers, diluents, surfact­ ants, dipsersants and solvents may also be incorporated. Such a herbicidal composition may contain a herbicidally effective amount, for example about 0.1 to about 90%, of the compound of general formula (I). The compounds of general formual (I) in accord­ ance with this invention can also be used in admixture with insecticides, fungicides, other agricultural chemi­ cals, fertilizer materials, soil coditioners, etc. Thus, according to this invention, there is provided a herbicidal composition comprising a herbi­ cidally effective amount of the haloacetamide compound represented by general formula (I) and an agriculturally acceptable diluent or carrier. There is further provided in accordance wiht this invention a method of controlling the growth of undesired vegetation which comprises applying an effec­ tive amount of the haloacetamide compound of general formula (I) to the locus to b protected from the undesired vegetation. The following examples illustrate the present invention more specifically. It should be understood that the invention is in no way limited to these examples alone. EXAMPLE 1 N-(1-methylbenzylidene)-2',6'-dimethylaniline (4.57g; 0.020 mole) was dissolved in 25 ml of N,N-­ dimethylformamide (DMF for short). With stirring at room temperature, a solution of 2.48g (0.022 mole) of chloro­ acetyl chloride in 5 ml of DMF was gradually added. The mixture was stirred for a while at room temperature, and then heated at 60°C for 2 hours. The reaction solution was cooled to room temperature, and washed twice with 100 ml of ether. The organic layer was extracted with 100 ml of ether. The ethereal layer was dried over sodium sulfate, and then ether was distilled off. The resulting solid was recrystallized from a mixture of benzene and hexane to give 4.34g of colorless crystals having a melting point of 91 to 92°C. The infrared absorption spectrum of the color­ less crystals was measured, and is shown in Figure 1. The infrared absorption spectrum chart showed an absorp­ tion based on the C-H at 3100 - 2900 cm⁻¹ assigned to the C-H bond, a strong absopriton at 1680 cm⁻¹ assigned the carbonyl linkage of the amide group, and a weak absorption at 1615 cm⁻¹ assigned to the >C=C< bond. The mass spectrum of the product showed a molecular ion peak (M ⊕ ) at m/e 299, a peak correspond­ ing to M ⊕ -Cl at m/e 264, and a peak corresponding to M ⊕ -COCH₂Cl at m/e 222. The ¹H-nuclear magnetic resonance spectrum (δ, ppm: tetramethylsilane as an internal standard, deuterochloroform as a solvent) of the product was measured, and the results are shown in Figure 2. The results of its analysis were as follows:- The elemental analysis of the product showed C72.08%, H5.98%, and N4.80%; which well agreed with the calculated values for the composition formula C₁₈H₁₈NClO (299.80), which were C72.11%, H6.05% and N4.67%. The above results led to the determination that the isolated product was N-(1-phenyl)ethenyl-N-chloro­ aceto-2',6'-dimethylanilide. The yileld was 71%. This compound is designated as compound No. 1. EXAMPLE 2 N-(ethoxymethylidene)-(1-phenyl-2,2-dimethyl­ ethenyl)amine (1.12g; 0.0055 mole) was dissolved in 15ml of benzene, and with stirring under cooling, a solution of 0.80g (0.0071 mole) of chloroacetyl chloride and 1.02g (0.0075 mole) of trichlorosilane in 5 ml of benzene was gradually added dropwise. The mixture was stirred over­ night at room temperature, and neutralized with an aque­ ous solution of potassium carbonate under ice cooling. The organic layer was extracted with ether, and dried over sodium sulfate. The low-boiling components were evaporated, and the resulting yellow liquid was purified by column chromatography (silica gel) to give 0.71g of a pale yellow viscous liquid. The infrared absorption spectrum of the result­ ing compound showed an absorption at 3100 to 2800 cm⁻¹ assigned to the C-H bond, a strong absorption at 1680 cm⁻¹ assigned to the >C=O linkage of the amide, and an absorption based at 1600 cm⁻¹ assigned to the >C=C< bond. The mass spectrum of the product showed a molecular ion peak (M ⊕ ) at m/e 281, a peak corresponding to M ⊕ -OC₂H₅ at m/e 236, and a peak corresponding to M ⊕ -CH₂OC₂H₅ at m/e 222. The ¹H-nuclear magnetic resonance spectrum (δ, ppm: tetramethylsilane as an internal standard, deuterochloroform as a solvent) of the product was measured. The results of its anlaysis were as follows. The elemental analysis values of the products were C64.10%, H7.09%, N5.01%, which well agreed with the calculated values for the composition formula C₁₅H₂₀NClO (281.78), which were C63.94%, H7.15%, N.4.97%. The above results led to the determination that the isolated product was N-(1-phenyl-2,2-dimethyl)ethenyl-­ N-chloroaceto-ethoxymethylamide. The yield was 46%. The resulting compound is designated as compound No. 2. EXAMPLE 3 N-(1-phenyl-2,2-dimethyl)ethylidene-2'-methoxy­ ethylamine (2.06g; 0.01 mole) was dissolved in 20 ml of DMF, and with stirring at room temperature, 1.52 g (0.013 mole) of chloroacetyl chloride was added gradually. The reaction solution was heated at 60°C for 2 hours, then cooled to room temperature, and washed with water and an aqueous solution of sodium carbonate. The organic layer was extracted with ether. The ethereal layer was dried over sodium sulfate, and the ether was distilled off. The resulting viscous liquid was purified by column chromatography (silica gel) to give 1.90 g of a pale yellow viscous liquid. The infrared absorption spectrum of the result­ ing compound showed an absorption at 3100 to 2800 cm⁻¹ assigned to the C-H bond, a strong absorption at 1670 cm⁻¹ assigned to the >C=O linkage of the amide, and an absorption at 1600 cm⁻¹ assigned to the >C=C< linkage. The mass spectrum of the resultilng compound showed a molecular ion peak (M ⊕ ) at m/e 281, a peak corresponding to M ⊕ -OCH₃ at m/e 266, and a peak corre­ sponding to M ⊕ -Cl at m/e 246. The ¹H-nuclear magnetic resonance spectrum (δ, ppm: tetramethylsilane as an internal standard, deuterochloroform as a solvent) of the resulting compound was measured. The results of analysis were shown below. The elemental analysis values of the product were C63.83%, H7.21%, N5.12%, which well agreed with the calculated values for the composition formula C₁₅H₂₀NClO (281.78), namely C63.94%, H7.15%, N4.97%. The above results led to the determination that the isolated product was N-[1-(phenyl)-2,2-(dimethyl)­ ethenyl]-N-chloroaceto-2'-methoxyethylamide. The yield of the product was 67%. The resulting compound is desig­ nated as compound No. 3. EXAMPLE 4 A solution of 1.12g (0.0099 mole) of chloro­ acetyl chloride in 5ml of benzene was gradually added dropwise with stirring under cooling to a solution of 1.29g (0.0074 mole) of N-vinyl-(1-phenyl-2,2-dimethyl­ ethenyl)amine in 10 ml of benzene. The mixture was stirred for 30 minutes under ice cooling, and then 1.41g (0.010 mole) of N-trimethylsilylpyrazole was added drop­ wise. The mixture was then stirred overnight at room temperature. The reaction mixture was washed with water, and the organic layer was extracted with benzene. The benzene layer was dried over sodium sulfate, and low-boiling components were removed. The resulting yellow viscous liquid was purified by column chromato­ graphy (silica gel) to give 1.00 g of colorless crystals. The infrared absorption spectrum of the result­ ing compound showed an absorption at 3200 to 2800 cm⁻¹ assigned to the C-H bond and a strong absorption at 1665 cm⁻¹ assigned to the >C=O linkage of the amide. The mass spectrum of the product showed a molecular ion peak (M ⊕ ) at m/e 318, a peak corresponding The ¹H-nuclear magnetic resonance spectrum (δ, ppm: tetramethylsilane as an internal standard, deuterochloroform as a solvent) was measured. The results of its analysis are shown below. (a) 7.29 ppm (s, 5H) (b) 1.47 ppm (d, 6H) (c) 4.38 ppm, 4.00 ppm (dd, 2H) (d) 1.27 ppm (d, 3H) (e) 6.93 ppm (q, 1H) (f) 7.60 ppm (d, 1H) (g) 6.19 ppm (m, 1H) (h) 7.42 ppm (d, 1H) The elemental analysis values of the product were C64.41%, H6.29%, N12.98%, which well agreed with the calculated values for the composition formula C₁₇H₂₀N₃ClO (317.81), namely C64.24%, H6.34%, N13.22%. The above results led to the determination that the isolated product was N-[1-(phenyl)-2,2-(dimethyl)­ ethenyl]-N-chloroaceto-[1'-(1"-pyrazolyl)ethyl]amide. The yield was 42%. The resulting product is designated as compouind No. 4. EXAMPLE 5 Various chloroacetamide compounds were synthe­ sized as in Examples 1 to 4. Table 1 summarizes the appearances, the boiling points or melting points, the characteristic absorptions in infrared absorption spectra, and the elemental analysis values of the synthesized compounds. R₁, R₂, R₃ and R₄ in the table correspond to R₁, R₂, R₃ and R₄ in the following formula. The boiling points in Table 1 were measured under reduced pressure (mmHg), and are indicated with the omission of mmHg, for example as 153°C/0.9 (=153°C/0.9 mmHg). EXAMPLE 6 Various haloacetamide compounds were synthesized as in Examples 1 to 5. The structures of the compounds were determined by infrared absorption spectroscopy, mass spectroscopy, ¹H-nuclear magnetic resotnance scpectro­ scopy and elemental analysis. Table 2 summarizes the substituents and elemental analysis values of the com­ pounds. R₁, R₂, R₃, R₄ and Y in the table correspond to R₁, R₂, R₃, R₄ and Y in the following formula. FORMULATION EXAMPLE 1 Wettable Powder:- Ten parts of N-(1-phenyl)ethenyl-N-chloroaceto-­ 2',6'-dimethylanilide (compound No. 1) obtained in Example 1, 85 parts of a 2:1 mixture of Zieklite (a tradename, a product of Zieklite Kogyo K.K.) and Kunlite (tradename a product of Kunimine Kogyo K.K.) and 5 parts of Sorpol 800A (tradename, a product of Toho Chemical Industrial Co., Ltd.) as a surfactant were mixed and pulverized uniformly to give a 10% wettable powder. FORMULATION EXAMPLE 2 Emulsion:- Twenty parts of N-(1-phenyl-2,2-dimethyl)­ ethenyl-N-chloroaceto-ethoxymethylamide (compound No. 2) obtained in Example 2, 70 parts of xylene and 10 parts of Sorpol 800A as a surfactant were mixed to form a 20% emulsion. FORMULATION EXAMPLE 3 Granules:- Five parts of N-(1-phenyl-2,2-dimethyl)ethenyl-­ N-chloroaceto-2'-methoxyethylamide (compound No. 3), 50 parts of bentonite (a product of Kunimine Kogyo K.K.), 40 parts of Kunilite and 5 parts of Sorpol 800A as a sur­ factant were mixed and pulverized uniformly. Water was added, and the mixture was stirred uniformly to form a paste-like mixture. The mixture was extruded from a hole having a diameter of 0.7mm, dried and cut to a length of 1 to 2mm to form 5% granules. EXAMPLE 7 Uplant farm soil (clay loam) was filled in porcelain pots (1/8850 ares). Seeds of various plants were sown in the soil to a depth of 0.5 to 1 cm. A water dilution of a wettable powder of each of the compounds indicated in Table 1, prepared as in Formulation Example 1, was sprayed onto the soil surface at a predetermined rate of application. After the treatment, the plants were grown in a greenhouse kept at an average atmospheric temperature of 25°C. Two weeks later, the herbicidal effect of each of the test compounds was examined, and the results are shown in Table 3. The evaluation was made on a scale of 6 grades where 0 indicates normal growth, 5 indicates complete kill, and 1 to 4 indcate varying degrees of growth between "normal growth" and "complete kill". A in the column of Compound No. in Table 3 is a known haloacetanilide of the following formula used for comparison. The results given in Table 3 demonstrate that the compounds of formula (I) in accordance with this invention have better herbicidal activity and selectivity than compound A. In Table 3, letters a to m in the column of "Plant" represent the following plants. a: rice b. wheat c. corn d. soybean e. cotton f. barnyard grass g. large crabgrsss h. green foxtail i. pigweed j. large smartweed k. blue morning glory 1. yellow cyperus m. hairy beggarticks EXAMPLE 8 In the same way as in Example 7, each of the test compounds shown in Table 4 was subjected to a soil treatment test at lower rates of application, and the results are shown in Table 4. A, B and C given in the column of Compouind No. in Table 4 represent the following compounds. Compound A (same as in Example 7) It is evident from the results given in Table 4 that the active compounds in accordance with this in­ vention have better herbicidal activity than the compara­ tive compounds A, B and C. The letters a to m given in the column of "Plant" in Table 4 have the same meanings as in Table 3. EXAMPLE 9 Upland farm soil (clay loam) was filled into porcelain pots (1/8850 ares), and seeds of various plants were sown in the soil to a depth of 0.5 to 1 cm, and grown in a greenhouse kept at an average atmospheric pressure of 25°C. Two weeks later, a water dilution of a wettable powder of each of the test compounds shown in Table 5, prepared as in Formulation Example 1, was sprayed onto the leaves of the plants at a predetermined rate of application. After the treatment, the plants were grown in a greenhouse, and two weeks later, the herbicidal effect of each of the test compounds was examined, and rated on the same standards as in Example 7. The results are shown in Table 5. The letters representing the plants in Table 5 were the same as shown below Table 3. EXAMPLE 10 Paddy soil (alluvial soil) stirred after addi­ tion of water was filled into porcelain pots (1/8850 ares). Seeds of paddy weeds were sown and rice seedlings (variety: "akinishiki") in the 3-leaf stage were trans­ planted to a depth of 1 cm. Water was added to maintain a submerged state with a depth of 3 cm. A water dilution of a wettable powder of each of the test compounds shown in Table 6, prepared as in Formulation Example 1, was dropped at a predetermined rate of application onto the simulated paddy at the time of germination of the weeds. The plants were grown in a greenhouse kept at an average atmospheric temperature of 25°C. Three weeks later, the herbicidal effect of each of the test compounds was examined and rated on the same standard as in Example 7. The results are shown in Table 6. In the table, the letter f is the same as shown below Table 3, and the ltters n to q represent the following plants. n: umbrella plant o: three-squre grass p: monochoria q: broad-leaved weeds [false pimpernel, "azeto­ garashi" ( Vandellia angustifolia Bentham) and "kikashigusa" ( Rotala Indica Koehne.)]

Claims: 1. A haloacetamide compound of the following formula (I) wherein R₁ represents a substituted or unsubstituted C₆-C₁₄ aryl group or a substituted or unsubsti­ tuted C₃-C₈ heteroaryl group having one or two hetero atoms selected from the group consist­ ing of O, S and N, R₂ and R₃, independently from each other, represent a hydrogen atom, a C₁-C₆ alkyl group or a C₁-C₆ alkoxy group, or R₂ and R₃, taken together, represent a C₂-C₁₆ alkylene group, R₄ represents a substituted or unsubstituted C₁-C₁₂ alkyl group, a substituted or unsubsti­ tuted C₆-C₁₄ aryl group, a C₂-C₁₂ alkenyl group or a C₂-C₁₂ alkynyl group, and Y represents a halogen atom selected from the group consisting of Cl, Br and I. 2. The haloacetamide compound of claim 1 wherein the substituent of the substituted aryl or heteroaryl group represented by R₁ is a member selected from the class consisting of C₁-C₆ alkyl groups, halogen atoms, C₁-C₆ alkoxy groups, C₁-C₆ haloalkyl groups, C₁-C₆ alkylthio groups, a phenoxy group unsubstituted or substi­ tuted by a member selected from C₁-C₆ alkyl groups and halogen atoms, and a phenyl group unsubstituted or substituted by a member selected from C₁-C₆ alkyl groups and halogen atoms. 3. The haloacetamide compound of claim 1 wherein the substituent of the substituted alkyl group repre­ sented by R₄ is a member selected from the class con­ sisting of halogen atoms, C₁-C₆ alkoxy groups, C₁-C₆ alkyl­ thio groups, a phenoxy group unsubstituted or substituted by a member selected from C₁-C₆ alkyl groups, C₁-C₆ alkoxy groups, C₁-C₆ alkylthio groups and halogen atoms, a cyano group, a phenyl group unsubstituted or substi­ tuted by a member selected from C₁-C₆ alkyl groups, C₁-C₆ alkoxy groups, C₁-C₆ alkylthio groups and halogen atoms, C₃-C₅ heteroaryl groups having one or two hetero atoms selected from O, S and N and being unsubstituted or substituted by a member selected from C₁-C₆ alkyl groups and halogen atoms, C₂-C₆ heterocycloalkyl groups having one or two hetero atoms selected from O, S and N and being unsubstituted or substituted by C₁-C₆ alkyl groups, alkoxycarbonyl groups having 1 to 6 carbon atoms in the alkoxy moiety, alkyl carbonyloxy groups having 1 to 6 carbon atoms in the alkyl moiety and being unsubsti­ tuted or substituted by halogen atoms, C₂-C₆ alkenyloxy groups, and C₂-C₆ alkynyloxy groups. 4. The haloacetamide compound of claim 1 wherein the substituent of the substituted aryl group represented by R₄ is a member selected from the class consisting of halogen atoms, C₁-C₆ alkyl groups unsubstituted or substituted by halogen atoms, C₁-C₆ alkylthio groups and C₁-C₆ alkoxy groups. 5. The haloacetamide compound of claim 1 wherein the aryl group represented by R₁ and R₄ is a member selected from phenyl and naphthyl groups. 6. The haloacetamide compound of claim 1 wherein the heteroaryl group represented by R₁ is a furyl or thienyl group. 7. A herbicidal composition comprising a herbicidal­ ly effective amount of the haloacetamide compound of formula (I) set forth in claim 1, and an agriculturally acceptable diluent or carrier. 8. The herbicidal composition of claim 7 wherein the amount of the haloacetamide compound is about 0.1 to 90% by weight based on the weight of the composition. 9. Use of the haloacetamide compound of formula (I) set forth in claim 1 as a herbicide. 10. A method of controlling the growth of undesired vegetation which comprises applying an effective amount of the haloacetamide compound of formula (I) set forth in claim 1 to the locus to be protected from the undesired vegetation. 11. The method of claim 10 wherein the amount of the haloacetamide compound of formula (I) is about 2 to about 3,000 g/10 ares.

Inventors: KATO, SHOZO, OGASAWARA, MASARU, OKAMOTO, HIDENORI, TAKEMATSU, TETSUO
Applicants: TOKUYAMA SODA KABUSHIKI KAISHA
Application year: 1986
Main classification: C07C103
IPC codes: C07D417, C07D333, C07D295, C07D207, C07C231, C07C233, C07D231, C07D277, A01N43, A01N39, A01N37, C07D215, C07D317, C07D521, C07D211, C07D307, C07D213, C07D409, C07D405, C07D401, C07C67