DE19704370A1 - Substituted benzoxazolyloxyacetanilides - Google Patents

Abstract

The invention relates to novel substituted benzoxazolyloxyacetanilides of formula (I) in which R<1> is a straight-chain or branched alkyl with between 2 and 4 carbon atoms, R<2> is a straight-chain or branched alkyl with between 2 and 6 carbon atoms, and X is hydrogen or halogen. The invention also relates to a method and novel intermediate products for producing said benzoxazolyloxyacetanilides, and to their use as herbicides.

Description

The invention relates to new substituted benzoxazolyloxyacetanilides, a process and new intermediates for their manufacture and their use as herbicides.

It is already known that certain substituted benzoxazolyloxyacetanilides have herbicidal properties (cf. EP 037 524, cf. also EP 005 501, EP 037 527, DE 30 38 652, DE 37 24 467, DE 42 18 433).

The effect of this before known compounds, however, especially at low application rates and Concentrations, not completely satisfactory in all areas of application.

The new substituted benzoxazolyloxyacetanilides of the general formula (I) have now been found

in which
R ^{1 represents} straight-chain or branched alkyl having 2 to 4 carbon atoms,
R ^{2 represents} straight-chain or branched alkyl having 2 to 6 carbon atoms and
X represents hydrogen or halogen.

It has also been found that the new substituted benzoxazolyloxyacetanilides of the general formula (I) are obtained if halobenzoxazoles of the general formula (II)

in which
X has the meaning given above and
X ^{1 represents} halogen,
with hydroxyacetanilides of the general formula (III)

in which
R ¹ and R ^{2 have} the meaning given above,
if appropriate in the presence of an acid binder and if appropriate in the presence of a diluent.

Finally, it was found that the new substituted benzoxazolyloxyacetanilides of the general formula (I) have interesting herbicidal properties.

The invention preferably relates to compounds of the formula (I) in which
R ^{1 represents} ethyl, n- or i-propyl, n-, i- or s-butyl,
R ^{2 represents} ethyl, n- or i-propyl, n-, i-, s- or t-butyl, n-, i-, s- or t-pentyl and
X represents hydrogen fluorine, chlorine or bromine.

The invention relates in particular to compounds of the formula (I) in which
R ^{1 represents} ethyl or i-propyl,
R ^{2 represents} ethyl, n- or i-propyl, n-, i- or s-butyl and
X represents hydrogen fluorine or chlorine.

The radicals listed above or listed in preferred areas definitions apply both to the end products of the formula (I) and correspondingly for the starting or intermediate products required for the production. This Residual definitions can be between themselves, that is, between the specified ones areas can be combined as required.

If, for example, 2-chloro-benzoxazole and N-ethyl-N- (2-ethyl-phenyl) -hydroxyacetamide are used as starting materials, the course of the reaction in the process according to the invention can be outlined using the following formula:

The halobenzoxazoles to be used as starting materials in the process according to the invention for the preparation of compounds of the formula (I) are generally defined by the formula (II). In the formula (II), X preferably or in particular has the meaning which has already been mentioned above in connection with the description of the compounds of the formula (I) according to the invention preferably or as particularly preferred for X; X ¹ preferably represents fluorine, chlorine or bromine, especially chlorine.

The starting materials of formula (II) are known and / or can be per se known processes can be produced (cf. DE 32 07 153, DE 33 34 417, EP 43573, EP 572893).

Formula (III) provides a general definition of the hydroxyacetanilides to be used further as starting materials in the process according to the invention. In the formula (III), R ¹ and R ² preferably or in particular have those meanings which have already been given above in connection with the description of the compounds of the formula (I) according to the invention preferably or as particularly preferred for R ¹ and R ² .

The starting materials of the formula (III) are not yet known from the literature; she are also the subject of the present application as new substances.

The new hydroxyacetanilides of the general formula (III) are obtained if acetoxyacetanilides of the general formula (IV)

in which
R ¹ and R ^{2 have} the meaning given above,
with methanol, optionally in the presence of an acid acceptor, such as. B. sodium methylate, at temperatures between 40 ° C and 80 ° C (see. The manufacturing examples).

The acetoxyacetanilides of the general formula required as precursors (IV) are not yet known from the literature; as new substances they are also counter stood the present application.

The new acetoxyacetanilides of the general formula (IV) are obtained if chloroacetanilides of the general formula (V)

in which
R ¹ and R ^{2 have} the meaning given above,
with alkali metal acetates, such as. B. sodium acetate, optionally in the presence of a diluent, such as. B. N, N-dimethyl-formamide, at temperatures between 80 ° C and 150 ° C (see. The preparation examples).

The chloroacetanilides of the general formula (V) required as precursors are known and / or can be produced by methods known per se (cf. US 3268584, US 3345151, GB 1565894, production examples).

As a diluent for carrying out the process according to the invention for Preparation of the compounds of general formula (I) occur in addition to water all inert organic solvents. These include in particular ali phatic, alicyclic or aromatic, optionally halogenated hydrocarbons  substances such as gasoline, benzene, toluene, xylene, chlorobenzene, dichlorobenzene, Petroleum ether, hexane, cyclohexane, dichloromethane, chloroform, carbon tetrachloride; Ethers, such as diethyl ether, diisopropyl ether, dioxane, tetrahydrofuran or ethylene glycol dimethyl or diethyl ether; Ketones, such as acetone, butanone or methyl iso butyl ketone; Nitriles such as acetonitrile, propionitrile or butyronitrile; Amides like N, N-dimethylformamide, N, N-dimethylacetamide, N-methylformanilide, N-methyl pyrrolidone or hexamethylphosphoric triamide; Esters such as methyl acetate or ethyl acetate; Sulfoxides such as dimethyl sulfoxide; Alcohols, such as methanol, Ethanol, n- or i-propanol, ethylene glycol monomethyl ether, ethylene glycol mono ethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, the Mix with water or pure water.

In general, acid binders for the process according to the invention are the usual inorganic or organic bases or acid acceptors in Consideration. These preferably include alkali metal or alkaline earth metal or acetates, amides, carbonates, bicarbonates, hydrides, hydroxides or alkanolates, such as for example sodium, potassium or calcium acetate, lithium, sodium, potassium or Calcium amide, sodium, potassium or calcium carbonate, sodium, potassium or Calcium hydrogen carbonate, lithium, sodium, potassium or calcium hydride, Lithium, sodium, potassium or calcium hydroxide, sodium or potassium methanolate, ethanolate, -n- or -i-propanolate, -n-, -i-, -s- or -t-butanolate; Farther also basic organic nitrogen compounds, such as trimethylamine, Triethylamine, tripropylamine, tributylamine, ethyl-diisopropylamine, N, N-dimethyl cyclohexylamine, dicyclohexylamine, ethyl-dicyclohexylamine, N, N-dimethyl-aniline, N, N-dimethyl-benzylamine, pyridine, 2-methyl, 3-methyl, 4-methyl, 2,4-dimethyl, 2,6-dimethyl-, 3,4-dimethyl- and 3,5-dimethyl-pyridine, 5-ethyl-2-methyl-pyridine, 4-dimethylamino-pyridine, N-methyl-piperidine, 1,4-diazabicyclo [2,2,2] octane (DABCO), 1,5-diazabicyclo [4,3,0] non-5-ene (DBN), or 1,8-diazabicyclo [5,4,0] -undec-7-ene (DBU).  

The reaction temperatures can be carried out when carrying out the process according to the invention Process can be varied over a wide range. Generally you work at temperatures between -20 ° C and 100 ° C, preferably between 0 ° C and 60 ° C.

The process according to the invention is generally carried out under normal pressure leads. However, it is also possible to increase the process according to the invention or reduced pressure - generally between 0.1 bar and 10 bar to lead.

To carry out the process according to the invention, the starting materials in generally used in approximately equimolar amounts. However, it is also possible to use one of the components in a larger excess. The Reaction is generally carried out in a suitable diluent were carried out an acid binder and the reaction mixture is in space agitated several hours at the required temperature. The on work is carried out according to customary methods (cf. the manufacturing examples).

The active compounds according to the invention can be used as defoliants, desiccants, kraut tabs killers and especially used as a weed killer. Weeds in the broadest sense are understood to mean all plants that are found in places grow where they are undesirable. Whether the substances according to the invention as total or Selective herbicides act essentially depends on the amount used.

The active compounds according to the invention can, for. B. used in the following plants will:

Dicotyledon weeds of the genera

Sinapis, Lepidium, Galium, Stellaria, Matricaria, Anthemis, Galinsoga, Chenopodium, Urtica, Senecio, Amaranthus, Portulaca, Xanthium, Convolvulus, Ipomoea, Polygonum, Sesbania, Ambrosia, Cirsium, Carduus, Sonchus, Solanum, Rorippa, Rotala, Lindernia, Lamium, Veronica, Abutilon, Emex, Datura, Viola, Galeopsis, Papaver, Centaurea, Trifolium, Ranunculus, Taraxacum.  

Dicotyledon cultures of the genera

Gossypium, Glycine, Beta, Daucus, Phaseolus, Pisum, Solanum, Linum, Ipomoea, Vicia, Nicotiana, Lycopersicon, Arachis, Brassica, Lactuca, cucumis, cucurbita.

Monocotyledonous weeds of the genera

Echinochloa, Setaria, Panicum, Digitaria, Phleum, Poa, Festuca, Eleusine, Brachiaria, Lolium, Bromus, Avena, Cyperus, Sorghum, Agropyron, Cynodon, Monochoria, Fimbristylis, Sagittaria, Eleocharis, Scirpus, Paspalum, Ischaemum, Sphenoclea, Dactyloctenium, Agrostis, Alopecurus, Apera.

Monocot cultures of the genera

Oryza, Zea, Triticum, Hordeum, Avena, Secale, Sorghum, Panicum, Saccharum, Pineapple, Asparagus, Allium.

However, the use of the active compounds according to the invention is by no means limited to these Limited genres, but extends in the same way to others Plants.

The compounds of the general formula (I) according to the invention are suitable in Depending on the concentration for total weed control z. B. on industrial and Track systems and on paths and squares with and without tree cover. As well can the compounds for weed control in permanent crops, e.g. B. Forst, ornamental wood, fruit, wine, citrus, nut, banana, coffee, tea, rubber, oil palm, Cocoa, berry fruit and hop plants, on ornamental and sports turf and Pastures and for selective weed control in annual crops be used.

The compounds of formula (I) according to the invention are particularly suitable for selective control of monocotyledon and dicotyledon weeds in monocotyledons Cultures such as B. in rice after planting.  

The active ingredients can be converted into the usual formulations, such as Solutions, emulsions, wettable powders, suspensions, powders, dusts, pastes, sol Liche powder, granules, suspension emulsion concentrates, impregnated with active ingredient Natural and synthetic substances as well as very fine encapsulation in polymeric substances.

These formulations are prepared in a known manner, e.g. B. by mixing of the active ingredients with extenders, i.e. liquid solvents and / or solid Carriers, if necessary using surface-active agents, that is Emulsifiers and / or dispersants and / or foaming agents.

In the case of the use of water as an extender, e.g. B. also organic Solvents are used as auxiliary solvents. As a liquid solvent essentially come into question: aromatics, such as xylene, toluene, or alkyl naphthalenes, chlorinated aromatics and chlorinated aliphatic hydrocarbons, such as Chlorobenzenes, chlorethylenes or methylene chloride, aliphatic hydrocarbons, such as cyclohexane or paraffins, e.g. B. petroleum fractions, mineral and vegetable Oils, alcohols such as butanol or glycol and their ethers and esters, ketones such as Acetone, methyl ethyl ketone, methyl isobutyl ketone or cyclohexanone, strongly polar Solvents such as dimethylformamide and dimethyl sulfoxide, and water.

As solid carriers come into question: B. ammonium salts and natural Rock flours, such as kaolins, clays, talc, chalk, quartz, attapulgite, Mont morillonite or diatomaceous earth and synthetic rock powder, such as highly disperse Silicic acid, aluminum oxide and silicates, come as solid carriers for granules in question: e.g. B. broken and fractionated natural rocks such as calcite, marble, Pumice, sepiolite, dolomite and synthetic granules from inorganic and organic flours and granules made of organic material such as sawdust, Coconut shells, corn cobs and tobacco stems; as emulsifying and / or foam Generating funds are possible: z. B. non-ionic and anionic emulsifiers, such as polyoxyethylene fatty acid esters, polyoxyethylene fatty alcohol ethers, e.g. B. alkyl aryl polyglycol ethers, alkyl sulfonates, alkyl sulfates, aryl sulfonates and protein  hydrolysates; as dispersants come into question: z. B. lignin sulfite and Methyl cellulose.

Adhesives such as carboxymethyl cellulose, natural, can be used in the formulations and synthetic powdery, granular or latex-shaped polymers are used, such as gum arabic, polyvinyl alcohol, polyvinyl acetate, and natural phospho lipids such as cephalins and lecithins and synthetic phospholipids. Other additives can be mineral and vegetable oils.

Dyes such as inorganic pigments, e.g. B. iron oxide, titanium oxide, ferro cyan and organic dyes such as alizarin, azo and metal phthalocyanine substances and trace nutrients such as salts of iron, manganese, boron, copper, cobalt, Molybdenum and zinc can be used.

The formulations generally contain between 0.1 and 95 percent by weight Active ingredient, preferably between 0.5 and 90%.

The active compounds according to the invention can be used as such or in their formulations also used in a mixture with known herbicides for weed control find, where ready formulations or tank mixes are possible.

Known herbicides are suitable for the mixtures, for example Acetochlor, acifluorfen (-sodium), aclonifen, alachlor, alloxydim (-sodium), Ametryne, Amidochlor, Amidosulfiiron, Asulam, Atrazine, Azimsulfuron, Benazolin, Benfuresate, bensulfuron (-methyl), bentazone, benzofenap, benzoylprop (-ethyl), bi alaphos, bifenox, bromobutide, bromofenoxim, bromoxynil, butachlor, butylates, Cafenstrole, carbetamides, chloromethoxyfen, chloramben, chloridazon, chlorine imuron (-ethyl), chloronitrofen, chlorosulfuron, chlorotoluron, cinmethylin, cin sulfuron, clethodim, clodinafop (-propargyl), clomazone, clopyralid, clopyra sulfuron, cloransulam (methyl), cumyluron, cyanazines, cycloates, cyclosulfamuron, Cycloxydim, cyhalofop (-butyl), 2,4-D, 2,4-DB, 2,4-DP, desmedipham, dialates, di camba, diclofop (-methyl), difenzoquat, diflufenican, dimefuron, dimepiperate, di  methachlor, dimethametryn, dimethenamid, dinitramine, diphenamid, diquat, di thiopyr, diuron, dymron, EPTC, esprocarb, ethalfluralin, ethametsulfuron (-methyl), Ethofumesate, ethoxyfen, etobenzanide, fenoxaprop (-ethyl), flamprop (-isopropyl), Flamprop (-isopropyl-L), Flamprop (-methyl), Flazasulfuron, Fluazifop (-butyl), Flumet sulam, flumiclorac (-pentyl), flumioxazin, flumipropyn, fluometuron, fluoro chloridone, fluoroglycofen (-ethyl), flupoxam, flupropacil, flurenol, fluridone, hallway oxypyr, Flurprimidol, Flurtamone, Fomesafen, Glufosinate (-ammonium), Glyphosate (isopropylammonium), halosafen, haloxyfop (-ethoxyethyl), hexazinones, Imazamethabenz (-methyl), Imazamethapyr, Imazamox, Imazapyr, Imazaquin, Imaz ethapyr, imazosulfuron, ioxynil, isopropalin, isoproturon, isoxaben, isoxaflutole, is oxapyrifop, lactofen, lenacil, linuron, MCPA, MCPP, mefenacet, metamitron, Metazachlor, methabenzthiazuron, metobenzuron, metobromuron, metolachlor, Metosulam, Metoxuron, Metribuzin, Metsulfuron (-methyl), Molinate, Monolinuron, Naproanilide, Napropamide, Neburon, Nicosulfijron, Norfiurazon Orbencarb, Oryzalin, Oxadiazon, Oxyfluorfen, Paraquat, Pendimethalin, Phenmedipham, Pipero phos, pretilachlor, primisulfuron (methyl), prometryn, propachlor, propanil, propa quizafop, propyzamide, prosulfocarb, prosulfuron, pyrazolate, pyrazosulfuron (ethyl), Pyrazoxyfen, pyributicarb, pyridate, pyrithiobac (-sodium), quinchlorac, quinmerac, Quizalofop (-ethyl), quizalofop (-p-tefuryl), rimsulfuron, sethoxydim, simazine, Simetryn, Sulcotrione, Sulfentrazone, Sulfometuron (-methyl), Sulfosate, Tebutam, Tebuthiuron, Terbuthylazine, Terbutryn, Thenylchlor, Thiafluamide, Thiazopyr, Thi diazimin, thifensulfuron (-methyl), thiobencarb, tiocarbazil, tralkoxydim, triallates, Triasulfuron, Tribenuron (-methyl), Triclopyr, Tridiphane, Trifluralin and Triflu sulfuron.

A mixture with other known active ingredients, such as fungicides, Insecticides, acaricides, nematicides, bird repellants, plant nutrients substances and soil structure improvement agents is possible.

The active substances can be used as such, in the form of their formulations or in the form thereof application forms prepared by further dilution, such as ready-to-use Solutions, suspensions, emulsions, powders, pastes and granules are used  will. The application is done in the usual way, e.g. B. by pouring, spraying, Spray, sprinkle.

The active compounds according to the invention can be used both before and after emergence of the plants are applied. They can also be planted in the soil before sowing be working.

The amount of active ingredient used can vary over a wide range. she depends essentially on the type of effect desired. In general the application rates are between 1 g and 10 kg of active ingredient per hectare of soil area, preferably between 5 g and 5 kg per ha.

The manufacture and use of the active compounds according to the invention are based on following examples.

Manufacturing examples example 1

3 ml of 33% aqueous sodium hydroxide solution (25 mmol NaOH) become one at 0 ° C cooled mixture of 3.1 g (20 mmol) of 2-chloro-benzoxazole, 4.4 g (20 mmol) of N- (3- Drop ethyl-phenyl) -N-i-propyl-hydroxyacetamide and 50 ml acetone while stirring given wisely. The reaction mixture is then at room temperature for 18 hours (about 20 ° C) stirred. Then the mixture is poured onto water and with Shaken methylene chloride. The organic phase is ge with sodium sulfate dries and filtered. The filtrate is concentrated in a water jet vacuum, the back stood digested with ligroin and the crystalline product obtained by suction isolated.

4.1 g (61% of theory) of N- (3-ethylphenyl) -N-i-propyl-α- (ben zoxazol-2-yloxy) acetamide with a melting point of 104 ° C.

Analogously to Example 1 and in accordance with the general description of the production process according to the invention, it is also possible, for example, to prepare the compounds of the formula (I) listed in Table 1 below.

Examples of the compounds of the formula (I)

Examples of the compounds of the formula (I)

Starting materials of formula (III) Example (III-1)

A mixture of 31 g (124 mmol) of N-ethyl-N- (3-ethyl-phenyl) -acetoxy-acetamide, 2 ml of saturated sodium methylate solution and 250 ml of methanol is under for 3 hours Reflux heated to boiling. Then the product is distilled under isolated under reduced pressure.

23 g (90% of theory) of N-ethyl-N- (3-ethyl-phenyl) -hydroxyacetamide are obtained from the boiling point 110 ° C (at 1 mbar).

Refractive index: n 20 | D = 1.5236.

Analogously to Example (III-1), the compounds of the formula (III) listed in Table 2 below can also be prepared, for example.

Examples of the compounds of the formula (III)

Examples of the compounds of the formula (III)

Starting materials of formula (IV) Example (IV-1)

A mixture of 29 g (128 mmol) of N-ethyl-N- (3-ethylphenyl) chloroacetamide, 15 g Sodium acetate and 100 ml of N, N-dimethylformamide is ge for 3 hours at 130 ° C. stirs. After cooling, the mixture is mixed with water / methylene chloride shakes, the organic phase separated, dried with sodium sulfate and filtered. The solvent is carefully distilled off from the filtrate under reduced pressure.

31.2 g (98% of theory) of N-ethyl-N- (3-ethyl-phenyl) -acetoxy-acetamide are obtained as an amorphous residue.

Analogously to Example (IV-1), the compounds of the formula (IV) listed in Table 3 below can also be prepared, for example.

Examples of the compounds of the formula (IV)

Examples of the compounds of the formula (IV)

Starting materials of formula (V) Example (V-1)

17 g (0.14 mol) of chloroacetyl chloride are heated to 80 ° C. with stirring Mixture of 21 g (0.14 mol) of N- (3-ethylphenyl) ethylamine and 120 ml of toluene added dropwise and the reaction mixture is then under for 2 hours Reflux heated to boiling. Then the solvent is added under ver carefully distilled off under reduced pressure.

30 g (95% of theory) of N-ethyl-N- (3-ethyl-phenyl) -chloroacetamide are obtained as oily residue of refractive index n 20 | D = 1.5308.

Analogously to Example (V-1), the compounds of the formula (V) listed in Table 4 below can also be prepared, for example.

Examples of the compounds of the formula (V)

Examples of the compounds of the formula (V)

Examples of use Example A / greenhouse Grafted water rice test / water surface treatment

Solvent: 5 parts by weight of acetone
Emulsifier: 1 part by weight of benzyloxypolyglycol ether

To produce a suitable preparation of active compound, it is mixed 1 part by weight of active ingredient with the specified amount of solvent gives the specified amount of emulsifier and dilute the concentrate to the desired Concentration.

Planters (size: 20 cm × 20 cm × 9 cm; surface: 1/2000 ares) are included Soil filled from a paddy field. Three rice plants (variety: Nihonbare) are grown in 2-3 leaf stages (approx. 10-15 cm high) transplanted into each of the vessels. Seeds of Echinochloa oryzoides, Monochoria vaginalis and Scirpus juncoides as well as from Various broad-leaved (dicotyledonous) plants are placed in the moist soil sown. The active substance treatment takes place at two different times: in a part of the planters 3-5 days after transplanting the rice (EA = "early application "), in the other part of the vessels 8-10 days after transplanting the Reises (LA = "late application"). At these times, the soil in the each planter up to a water depth of 3 cm and the Active ingredient preparation is then applied to the water surface. The Active ingredient concentration in the preparation does not matter, only the decisive factor Application rate of the active ingredient per unit area.

After application of the active ingredient, the plant pots are used for 2 days vertically descending water flow at a speed of 2-3 cm per day set. After that, the test batches are kept under flood conditions, the water depth is 3 cm.  

3 weeks after the drug application, the degree of damage to the plants rated in% damage (or weed action) compared to an unbe acted control.

Mean it
0% = no effect / damage (like untreated control)
100% = total annihilation

In this test, for example, the compounds according to Preparation Example 1 show 2, 3, 4, 5, 6, 7 and 9 with good tolerance to rice strong effect against Weeds.

Claims (10)

1. Substituted benzoxazolyloxyacetanilides of the formula (I),
in which
R ^{1 represents} straight-chain or branched alkyl having 2 to 4 carbon atoms,
R ^{2 represents} straight-chain or branched alkyl having 2 to 6 carbon atoms and
X represents hydrogen or halogen. 2. Compounds of formula (I) according to claim 1, characterized in that therein
R ^{1 represents} ethyl, n- or i-propyl, n-, i- or s-butyl,
R ^{2 represents} ethyl, n- or i-propyl, n-, i-, s- or t-butyl, n-, i-, s- or t-pentyl and
X represents hydrogen, fluorine, chlorine or bromine. 3. Compounds of formula (I) according to claim 1, characterized in that therein
R ^{1 represents} ethyl or i-propyl,
R ^{2 represents} ethyl, n- or i-propyl, n-, i- or s-butyl and
X represents hydrogen, fluorine or chlorine. 4. A process for the preparation of compounds of formula (I) according to claim 1, characterized in that halobenzoxazoles of the formula (II)
in which
X has the meaning given in claim 1 and
X ^{1 represents} halogen,
with hydroxyacetanilides of the formula (III)
in which
R ¹ and R ^{2 have} the meaning given in claim 1,
if appropriate in the presence of an acid binder and if appropriate in the presence of a diluent. 5. Herbicidal agents, characterized by a content of at least one A compound of formula (I) according to claim 1. 6. Use of compounds of formula (I) according to claim 1 for Combat unwanted plant growth. 7. A method of combating weeds, characterized in that compounds of formula (I) according to claim 1 on the weeds or lets their living space take effect. 8. A process for the preparation of herbicidal compositions, characterized in that that compounds of formula (I) according to claim 1 with extenders and / or surfactants mixed. 9. Hydroxyacetanilides of the formula (III)
in which
R ^{1 represents} straight-chain or branched alkyl having 2 to 4 carbon atoms and
R ^{2 represents} straight-chain or branched alkyl having 2 to 6 carbon atoms. 10. acetoxyacetanilides of the formula (IV),
in which
R ^{1 represents} straight-chain or branched alkyl having 2 to 4 carbon atoms and
R ^{2 represents} straight-chain or branched alkyl having 2 to 6 carbon atoms.