Cyclohexenonoximethers, process for their production and their application as herbicides

The invention relates to new herbicidally active cyclohexenone oxime ethers of the formula I.<chemistry id="chem0001" num="0001"><img file="EP0456089B1_D0001.tif" /></chemistry> in which the variables have the following meaning:<dl id="dl0001"><dt>R¹</dt><dd>a C₁-C₆ alkyl group;</dd><dt>X</dt><dd>halogen</dd><dt>n</dt><dd>1 until 5;</dd><dt>R²</dt><dd>a C₁-C₄ alkoxy-C₁-C₆ alkyl or C₁-C₄ alkylthio-C₁-C₆ alkyl group; a C₃-C₇-cycloalkyl group or a C₅-C₇-cycloalkenyl group, where these groups can carry one to three radicals, selected from a group consisting of C₁-C₄-alkyl, C₁-C₄-alkoxy, C₁-C₄-alkylthio, C₁-C₄ haloalkyl, hydroxy and halogen; a 5-membered saturated heterocycle which contains one or two heteroatoms selected from a group consisting of oxygen and sulfur and which can also carry one to three radicals selected from a group consisting of C₁-C₄-alkyl, C₁-C₄- Alkoxy, C₁-C₄ alkylthio and C₁-C₄ haloalkyl; a 6- or 7-membered saturated, mono- or di-unsaturated heterocycle containing one or two heteroatoms selected from a group consisting of oxygen and sulfur, where the heterocycle can carry one to three radicals selected from a group consisting of Hydroxy, halogen, C₁-C₄-alkyl, C₁-C₄-alkoxy, C₁-C₄-alkylthio and C₁-C₄-haloalkyl; a 5-membered heteroaromatic containing one to three heteroatoms, selected from a group consisting of two nitrogen atoms and one oxygen or sulfur atom, wherein this ring can carry one to three residues, selected from a group consisting of halogen, cyano, C₁ -C₄-alkyl, C₁-C₄-alkoxy, C₁-C₄-alkylthio, C₁-C₄-haloalkyl, C₂-C₆-alkenyl, C₂-C₆-alkenyloxy, C₂-C₆-haloalkenyl and C₁-C₄-alkoxy-C₁-C₄ -alkyl; the phenyl group or the pyridyl group, these groups being able to carry one to three radicals selected from a group consisting of halogen, nitro, cyano, C₁-C₄-alkyl, C₁-C₄-alkoxy, C₁-C₄- alkylthio, C₁- C₄-haloalkyl, C₃-C₆-alkenyloxy, C₃-C₆-alkynyloxy and -NR³R⁴, wherein</dd><dt>R³</dt><dd>Hydrogen, a C₁-C₄-alkyl group, a C₃-C₆-alkenyl group or a C₃-C₆-alkynyl group and</dd><dt>R⁴</dt><dd>Is hydrogen, a C₁-C Alkyl-alkyl group, a C₃-C₆-alkenyl group, a C₃-C₆-alkynyl group, a C₁-C₆-acyl group or a benzoyl radical, it being possible for the aromatic ring to carry one to three radicals selected from a group, consisting of nitro, cyano, halogen, C₁-C₄-alkyl, C₁-C₄-alkoxy, C₁-C₄-alkylthio and C₁-C₄-haloalkyl</dd></dl> mean, and the agriculturally usable salts of I and the esters of I with C₁-C₁₀ carboxylic acids or inorganic acids.

The invention also relates to a process for their preparation and their use as crop protection agents.

The cyclohexenone oxime ethers I according to the invention are obviously acidic in nature, ie they can form simple reaction products such as salts of alkali or alkaline earth compounds or enol esters.

The compounds of formula 1 can occur in several tautomeric forms, all of which are covered by the claim.

DE-A 38 38 309 and the corresponding European application EP-A-0 368 227 describe herbicidally active cyclohexenone oxime ethers whose general formula comprises the arylbutyleneoximinocyclohexanediones I defined at the outset. Specifically listed are among others 2- {1- [4- (3-fluorophenyl) butyloximino] propyl} -5- (2-ethylthio-propyl) -3-hydroxy-cyclohex-2-enone, 2- {1- [4- (3-fluorophenyl) butyloximino] butyl} -5- (2-ethylthio-propyl) -3-hydroxy-cyclohex-2-enone, 2- {1- [4- (4-fluorophenyl) butyloximino] propyl} -5- (2-ethylthio-propyl) -3-hydroxy-cyclohex-2-enone and 2- {1- [4- (4-fluorophenyl) butyloximino] butyl} -5- (2-ethylthio-propyl) -3-hydroxy-cyclohex-2-enone.

The invention was based on the object of synthesizing cyclohexenone oxime ethers which, compared to the known representatives of this class of substances, have greater selectivity in combating grass weeds in grassy crops such as, for example, rice.

In accordance with this task, the new cyclohexenone oxime ethers of the formula I defined at the outset were found which have a good herbicidal activity, preferably against species from the grass family (Gramineae). They are tolerated and therefore selective in broadleaved crops and in monocotyledonous plants, which are not among the Gramineae. Also included are compounds which also behave selectively in Gramineae crops and which simultaneously fight undesirable grasses.

The cyclohexenones of the formula I can be prepared in a manner known per se from already known derivatives of the formula II (EP-A 80 301, EP-A-125 094, EP-A 142 741, US-A 4 249 937, EP-A 137 174 and EP-A 177 913) and the corresponding hydroxylamines of the formula III can be prepared (EP-A 169 521).<chemistry id="chem0002" num="0002"><img file="EP0456089B1_D0002.tif" /></chemistry>

The reaction is expediently carried out in a heterogeneous phase in a solvent at a sufficient temperature below about 80 ° C. in the presence of a base and the hydroxylamine III is used in the form of its ammonium salt.

Suitable bases are e.g. B. carbonates, hydrogen carbonates, acetates, alcoholates or oxides of alkali or alkaline earth metals, in particular sodium hydroxide, potassium hydroxide, magnesium oxide, calcium oxide. Organic bases such as pyridine or tertiary amines can also be used. The base is added, for example, in an amount of 0.5 to 2 molar equivalents based on the ammonium compound.

Examples of suitable solvents are dimethyl sulfoxide; Alcohols such as methanol, ethanol and isopropanol; aromatic hydrocarbons such as benzene and toluene; chlorinated hydrocarbons such as chloroform and dichloroethane; aliphatic hydrocarbons such as hexane and cyclohexane; Esters such as ethyl acetate and ethers such as diethyl ether, dioxane and tetrahydrofuran. The reaction is preferably carried out in methanol using sodium bicarbonate as the base.

The reaction is complete after a few hours. The target compound can be isolated, for example, by concentrating the mixture, distributing the residue in methylene chloride / water and distilling off the solvent under reduced pressure.

However, the free hydroxylamine base, for example in the form of an aqueous solution, can also be used directly for this reaction; depending on the solvent used for compound II, a one- or two-phase reaction mixture is obtained.

Suitable solvents for this variant are, for example, alcohols such as methanol, ethanol, isopropanol and cyclohexanol; aliphatic and aromatic, optionally chlorinated hydrocarbons such as hexane, cyclohexane, methylene chloride, toluene and dichloroethane; Esters such as ethyl acetate; Nitriles such as acetonitrile and cyclic ethers such as dioxane and tetrahydrofuran.

Alkali metal salts of the compounds I can be obtained by treating the 3-hydroxy compounds with sodium or potassium hydroxide or alcoholate in aqueous solution or in an organic solvent such as methanol, ethanol, acetone and toluene.

Other metal salts such as manganese, copper, zinc, iron, calcium, magnesium and barium salts can be prepared from the sodium salts in a conventional manner, as can ammonium and phosphonium salts using ammonia, phosphonium, sulfonium or sulfoxonium hydroxides.

The compounds of type II can, for example, from the corresponding cyclohexane-1,3-diones of the formula IV<chemistry id="chem0003" num="0003"><img file="EP0456089B1_D0003.tif" /></chemistry> in the<dl id="dl0002" compact="compact"><dt>Y</dt><dd>Means hydrogen or methoxycarbonyl</dd></dl> by known methods, for example as described in Tetrahedron Lett., 2491 (1975).

It is also possible to prepare the compounds of the formula II via the intermediate stage of the enol esters V, which are obtained in the reaction of compounds of the formula IV with acid chlorides VI in the presence of bases and are then rearranged with certain imidazole or pyridine derivatives (JP-OS 79 / 063 052).<chemistry id="chem0004" num="0004"><img file="EP0456089B1_D0004.tif" /></chemistry>

The compounds of the formula IV are obtained via a number of known process steps starting from known precursors.

The hydroxylamines III are synthesized, for example, according to the reaction scheme below<ul id="ul0001" list-style="none"><li>A) the alkylation of N-hydroxyphthalimide VII with suitable phenylbutyl halides VIII and subsequent deprotection, for example with hydrazine or ethanolamine, analogously to examples from EP-A-244 786 or Houben-Weyl, Methods of Organic Chemistry, volume X / 1, page 1152ff.</li><li>B) Hydrogenation of N-4-phenylbutenyloxyphthalimides Xa, b, the preparation of which is described in DE-A 38 38 310, using suitable catalysts such as, for example, palladium on activated carbon, in suitable inert solvents such as, for example, methanol, tetrahydrofuran, dioxane and subsequent deprotection as above described. The hydrogenation is advantageously carried out at temperatures from 20.degree. C. to the boiling point of the solvent, in particular at room temperature, using the usual atmospheric pressure, positive or negative pressure techniques. A pressure range from 1 to 10, in particular 1 to 2, bar is preferred.</li></ul>

Reaction scheme:

<chemistry id="chem0005" num="0005"><img file="EP0456089B1_D0005.tif" /></chemistry> In the cyclic hydroxyimides VII, D is, for example, C₂-C₃-alkylene, C₂-alkenylene or a 5- or 6-ring containing up to 3 double bonds and optionally 1 nitrogen atom, for example phenylene, pyridinylene, cyclopentylene, cyclohexylene or cyclohexenylene. For example, the following substances can be used:<chemistry id="chem0006" num="0006"><img file="EP0456089B1_D0006.tif" /></chemistry>

The cyclic imide ethers VIII are cleaved analogously to a process described in EP-A 244 786 using alkanolamines. The hydroxylamines III can be isolated as free bases by this process or as salts after precipitation with acids. Well crystallizing salts are obtained by reacting the bases with oxalic acid.

With regard to the biological activity, cyclohexenones of the formula I are preferred in which the substituents have the following meanings:<dl id="dl0003"><dt>R¹</dt><dd>Alkyl such as methyl, ethyl, propyl, n-butyl, especially ethyl and propyl;</dd><dt>X</dt><dd>Halogen such as fluorine, chlorine, bromine and iodine, especially fluorine and chlorine;</dd><dt>n</dt><dd>1 to 5, in particular 1, 2 or 3. If there are several X radicals, the substituents can be identical or different.</dd><dt>R²</dt><dd>Alkyl as mentioned under R¹, which can preferably carry an alkoxy or alkylthio group listed below in the 1-, 2- or 3-position, in particular 2-ethylthiopropyl, or a cyclohexyl radical which can carry 1 to 3 methyl or hydroxyl groups, in particular 4 -Methylcyclohexyl and 3,4-dihydroxycyclohexyl; 5-membered heteroaryl such as pyrazolyl, isoxazolyl; a 6-membered heterocycle such as tetrahydropyran-3-yl, tetrahydropyran-4-yl and tetrahydrothiopyran-3-yl, a phenyl or a pyridyl radical, where the cyclic radicals one to three alkyl groups, alkoxy groups, alkylthio groups and / or haloalkyl groups and, in the case of 6-membered radicals, also halogen as mentioned under X or can carry hydroxy, for example Alkyl such as methyl, ethyl, propyl, 1-methylethyl, butyl, 1-methylpropyl, 2-methylpropyl and 1,1-dimethylethyl, especially methyl and 1,1-dimethylethyl, Alkoxy such as methoxy, ethoxy, propoxy, 1-methylethoxy, butoxy, 1-methylpropoxy, 2-methylpropoxy and 1,1-dimethylethoxy, in particular methoxy, ethoxy, 1-methylethoxy and 1,1-dimethylethoxy, Alkylthio such as methylthio, ethylthio, propylthio, 1-methylethylthio, butylthio, 1-methylpropylthio, 2-methylpropylthio and 1,1-dimethylethylthio, especially methylthio, Haloalkyl such as fluoromethyl, difluoromethyl, trifluoromethyl, chlorodifluoromethyl, dichlorofluoromethyl, Trichloromethyl, especially difluoromethyl, trifuormethyl. The 2,4,6-trimethylphenyl group is particularly preferred. The 5-membered heteroaromatics with the meaning R² can carry the following radicals as substituents: Halogen atom as mentioned under X, in particular fluorine and chlorine, In the case of the phenyl and pyridyl radicals, the following radicals are also suitable as substituents in addition to the groups mentioned above: Alkynyloxy such as 2-propynyloxy, especially propargyloxyphenyl. Amino, which can carry one or two acyl residues such as acetyl or benzoyl. Particularly preferred cyclohexenone oxime ethers of the formula I are summarized in the following table:</dd></dl><tables id="tabl0001" num="0001"><img file="EP0456089B1_D0007.tif" /></tables><tables id="tabl0002" num="0002"><img file="EP0456089B1_D0008.tif" /></tables><tables id="tabl0003" num="0003"><img file="EP0456089B1_D0009.tif" /></tables><tables id="tabl0004" num="0004"><img file="EP0456089B1_D0010.tif" /></tables>

The cyclohexenone oxime ethers I are suitable as herbicides, in particular for combating plant species from the gramineae family (grasses).

The cyclohexenone oxime ethers I or the herbicidal compositions comprising them can be sprayed, atomized, for example in the form of directly sprayable solutions, powders, suspensions, including high-strength aqueous, oily or other suspensions or dispersions, emulsions, oil dispersions, pastes, dusts, sprinkling agents or granules. Dusting, scattering or pouring can be used. The application forms depend on the purposes; in any case, they should ensure the finest possible distribution of the active compounds according to the invention.

Mineral oil fractions of medium to high boiling point, such as kerosene or diesel oil, also coal tar oils and oils of vegetable or animal origin, aliphatic, cyclic and aromatic hydrocarbons, for example, come as inert additives Toluene, xylene, paraffin, tetrahydronaphthalene, alkylated naphthalenes or their derivatives, methanol, ethanol, propanol, butanol, cyclohexanol, cyclohexanone, chlorobenzene, isophorone or strongly polar solvents, such as N, N-dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone or water .

Aqueous use forms can be prepared from emulsion concentrates, dispersions, pastes, wettable powders or water-dispersible granules by adding water. To prepare emulsions, pastes or oil dispersions, the substrates as such or dissolved in an oil or solvent can be homogenized in water by means of wetting agents, adhesives, dispersants or emulsifiers. However, concentrates consisting of active substance, wetting agent, adhesive, dispersant or emulsifier and possibly solvent or oil can also be prepared which are suitable for dilution with water.

The surface-active substances are the alkali metal, alkaline earth metal and ammonium salts of aromatic sulfonic acids, for example lignin, phenol, naphthalene and dibutylnaphthalenesulfonic acid, and of fatty acids, alkyl and alkylarylsulfonates, alkyl, lauryl ether and fatty alcohol sulfates, and salts of sulfated hexa- , Hepta- and octadecanols, as well as fatty alcohol glycol ether, condensation products of sulfonated naphthalene and its derivatives with formaldehyde, condensation products of naphthalene or of naphthalenesulfonic acids with phenol and formaldehyde, polyoxyethylene octylphenol ether, ethoxylated isooctyl, octyl or nonylphenol, alkylphenyl, tributylphenyl polyglycol ether, alkylaryl polyether alcohols, isotridecyl alcohol, fatty alcohol ethylene oxide condensates, ethoxylated castor oil or methyloxyalkylene glycol, ethoxylated alcohol oil, polyoxymethylene glycol, ethoxylated alcohol oil, polyoxyethylene glycol, ethoxylated alkylene glycol, ethoxylated alcohol oil, polyoxyethylene glycol, ethoxylated ethylene glycol, ethoxylated ethylene glycol, ethoxylated alcohol oil, polyoxyethylene glycol, ethoxylated ethylene glycol, ethoxylated alcohol, polyoxyethylene glycol, ethoxylated ethylene glycol, ethoxylated alcohol, polyoxyethylene glycol, ethoxylated alcohol, polyoxyethylene glycol, ethoxylated ethylene glycol, ethoxylated ethylene glycol, ethoxylated alcohol, polyoxyethylene glycol, ethoxylated glycolic oil, polyoxyethylene glycol, ethylenedilyl ether,

Powders, materials for broadcasting and dusts can be prepared by mixing or grinding the active substances together with a solid carrier.

Granules, for example coated granules, impregnated granules and homogeneous granules, can be prepared by binding the active ingredients to solid carriers. Solid carriers are mineral soils such as silicas, silica gels, silicates, talc, kaolin, limestone, lime, chalk, bolus, loess, clay, dolomite, diatomaceous earth, calcium and magnesium sulfate, magnesium oxide, ground plastics, fertilizers such as ammonium sulfate, ammonium phosphate, ammonium nitrate, Urea and vegetable products such as flour, tree bark, wood and nutshell flour, cellulose powder or other solid carriers.

The formulations contain between 0.02 and 95% by weight, preferably between 0.5 and 90% by weight, of active ingredient. The active ingredients are used in a purity of 90% to 100%, preferably 95% to 100% (according to the NMR spectrum).

The compounds I according to the invention can be formulated, for example, as follows:<ul id="ul0002" list-style="none"><li>I. 90 parts by weight of compound no. 1.05 are mixed with 10 parts by weight of N-methyl-α-pyrrolidone and a solution is obtained which is suitable for use in the form of tiny drops.</li><li>II. 20 parts by weight of compound no. 1.03 are dissolved in a mixture consisting of 80 parts by weight of xylene, 10 parts by weight of the adduct of 8 to 10 mol of ethylene oxide and 1 mol of oleic acid-N-monoethanolamide, 5 parts by weight of calcium salt of dodecylbenzenesulfonic acid and 5 parts by weight of the adduct of 40 moles of ethylene oxide to 1 mole of castor oil. By pouring the solution into 100,000 parts by weight of water and finely distributing it therein, an aqueous dispersion is obtained which contains 0.02% by weight of the active ingredient.</li><li>III. 20 parts by weight of compound no. 1.11 are dissolved in a mixture consisting of 40 parts by weight of cyclohexanone, 30 parts by weight of isobutanol, 20 parts by weight of the adduct of 7 mol of ethylene oxide and 1 mol of isooctylphenol and 10 parts by weight of the adduct of 40 mol of ethylene oxide and 1 mol of castor oil. Pouring the solution into 100,000 parts by weight of water and finely distributing it therein gives an aqueous dispersion which contains 0.02% by weight of the active ingredient.</li><li>IV. 20 parts by weight of active ingredient No. 1.11 are dissolved in a mixture consisting of 25 parts by weight of cyclohexanone, 65 parts by weight of a mineral oil fraction with a boiling point of 210 to 280 ° C. and 10 parts by weight of the adduct of 40 moles of ethylene oxide and 1 mole of castor oil. Pouring the solution into 100,000 parts by weight of water and finely distributing it therein gives an aqueous dispersion which contains 0.02% by weight of the active ingredient.</li><li>V. 20 parts by weight of active ingredient no. 1.05 are mixed well with 3 parts by weight of the sodium salt of diisobutylnaphthalene-α-sulfonic acid, 17 parts by weight of the sodium salt of lignosulfonic acid from a sulfite waste liquor and 60 parts by weight of powdered silica gel and ground in a hammer mill. By finely distributing the mixture in 20,000 parts by weight of water, a spray mixture is obtained which contains 0.1% by weight of the active ingredient.</li><li>VI. 3 parts by weight of active ingredient no. 1.03 are mixed with 97 parts by weight of finely divided kaolin. In this way, a dusting agent is obtained which contains 3% by weight of the active ingredient.</li><li>VII. 30 parts by weight of active ingredient no. 1.05 are intimately mixed with a mixture of 92 parts by weight of powdered silica gel and 8 parts by weight of paraffin oil which has been sprayed onto the surface of this silica gel. In this way, a preparation of the active ingredient with good adhesiveness is obtained.</li><li>VIII. 20 parts by weight of active ingredient No. 1.03 are intimately mixed with 2 parts by weight of calcium salt of dodecylbenzenesulfonic acid, 8 parts by weight of fatty alcohol polyglycol ether, 2 parts by weight of sodium salt of a phenol-urea-formaldehyde condensate and 68 parts by weight of a paraffinic mineral oil. A stable oily dispersion is obtained.</li></ul>

The agents can be applied pre-emergence or post-emergence. If the active ingredients are less compatible for certain crop plants, application techniques can also be used in which the herbicidal compositions are sprayed with the aid of sprayers in such a way that the leaves of the sensitive crop plants are not hit wherever possible, while the active ingredients are more undesirable on the leaves below them Plants or the uncovered floor area (post-directed, lay-by).

Depending on the season, target plants and growth stage, the application rates of active ingredient are 0.001 to 3 kg / ha, preferably 0.01 to 2.0 kg / ha.

In view of the detectable spectrum of activity for weed control, the tolerance for crop plants or the desired influence on the growth thereof, and in view of the variety of application methods, the compounds according to the invention can be used in a large number of crop plants. For example, the following crops can be considered:<tables id="tabl0005" num="0005"><img file="EP0456089B1_D0011.tif" /></tables><tables id="tabl0006" num="0006"><img file="EP0456089B1_D0012.tif" /></tables>

To widen the spectrum of activity and to achieve synergistic effects, the cyclohexenone derivatives of the formula I can be mixed with one another and also with representatives of other herbicidal or growth-regulating active compound groups and applied together. Examples of mixing partners are diazines, 4H-3,1-benzoxazine derivatives, benzothiadiazinones, 2,6-dinitroanilines, N-phenylcarbamates, thiolcarbamates, halocarboxylic acids, triazines, amides, ureas, diphenyl ethers, triazinones, uracils, benzofuran derivatives, quinoline carbonic acid derivatives, sulfonyl carboxylic acid derivatives, sulfonyl carboxylic acid derivatives, sulfonyl carbonic acid derivatives, sulfonyl carboxylic acid derivatives, sulfonyl carboxylic acid derivatives, sulfonyl carboxylic acid derivatives, sulfonyl carboxylic acid derivatives, sulfonyl carboxylic acid derivatives, sulfonyl carboxylic acid derivatives, sulfonyl carboxylic acid derivatives, sulfonyl carboxylic acid derivatives, sulfonyl carbonic acid derivatives, sulfonyl carbonic acid derivatives, sulfonyl carboxylic acid derivatives, sulfonyl carboxylic acid derivatives, sulfonyl carboxylic acid derivatives, sulfonyl carboxylic acid derivatives, and (Hetero) aryloxyphenoxypropionic acids, their salts, esters and amides and others into consideration.

It may also be useful to apply the cyclohexenone derivatives of the formula I or herbicides containing them, alone or in combination with other herbicides or else mixed with other crop protection agents, for example with agents for controlling pests or phytopathogenic fungi or bacteria. Also of interest is the miscibility with mineral salt solutions, which are used to remedy nutritional and trace element deficiencies. Non-phytotoxic oils and oil concentrates can also be added.

Examples

4-phenylbutyloxyamine<chemistry id="chem0007" num="0007"><img file="EP0456089B1_D0013.tif" /></chemistry>

Method A:

To 302 g (1.85 mol) of N-hydroxyphthalimide in 1.9 l of anhydrous N-methylpyrrolidone were added 167.5 g (1.21 mol) of potassium carbonate and 2 g of potassium iodide. After the reaction mixture had been heated to 60 ° C., 395.2 g (1.85 mol) of 4-phenylbutyl bromide were added dropwise and the mixture was kept at this temperature for a further 6 h. After cooling, the mixture was poured onto 6 l of ice water, taken up in dichloroethane, the organic phase was washed with dilute sodium hydroxide solution, dried and concentrated in vacuo. Yield: 397 g of N- (4-phenylbutyloxy) phthalimide (73%). 250 MHz ¹H NMR (DMSO-d₆) δ (ppm) = 1.65-1.85 (m, 4H); 2.66 (t, 2H); 4.18 (t, 2H) 7.1-7.4 (m, 5H); 7.86 (s, 4H).

81.8 g (1.34 mol) of ethanolamine were added to a solution of 396 g (1.34 mol) of the phthalimide ether obtained above in 1300 ml of ethyl acetate. The reaction mixture was heated at 60 ° C for 5 hours. The mixture was then stirred for a further 24 hours at room temperature, the crystals which had precipitated were filtered off, washed with a little ethyl acetate and passed through the combined mother liquors for 15 minutes in a strong hydrochloric acid gas stream, the internal temperature not exceeding 40.degree. The precipitated crystals were filtered off, washed with a little ethyl acetate and dried in vacuo. Yield: 148.5 g of 4-phenylbutyloxyamine hydrochloride (55%); Mp: 93-94 ° C. 250 MHz ¹H NMR (DMSO-d₆) α (ppm) = 1.5-1.7 (m, 4H); 2.58 (t, 2H); 4.04 (t, 2H) 7.1-7.3 (m. 5H); 11.1 (broad s, 3H).

4- (4-fluorophenyl) butyloxyamine

<chemistry id="chem0008" num="0008"><img file="EP0456089B1_D0014.tif" /></chemistry>

Method B: hydrogenation

N- (4- (4-fluorophenyl) butyloxy) phthalimide

2 g of palladium were added to a solution of 71.5 g (0.23 mol) of N- (4- (4-fluorophenyl) -3-butenyloxy) phthalimide (prepared according to DE-OS 38 38 310) in 300 ml of tetrahydrofuran Activated carbon (10%) given. The mixture was hydrogenated at a slight excess pressure until 1.2 times the theoretical amount of hydrogen had been consumed. It was suctioned off over kieselguhr, concentrated and the crude product was recrystallized from isopropanol. Yield: 62.8 g (87%); Mp .: 67-68 ° C 250 MHz ¹H NMR (DMSO-d₆) δ (ppm) = 1.8-1.9 (m, 4H); 2.65 (t, 2H); 4.15 (t, 2H) 7.0-7.35 (m, 4H); 7.86 (s, 4H).

61.8 g (0.197 mol) of the phthalimide ether previously prepared were added in portions to 92 mol of ethanolamine. After heating at 60 ° C. for 3 h, after cooling, it was poured into 400 ml of ice water and extracted with dichloroethane. The combined organic phases were washed with saturated sodium chloride solution, dried and concentrated in vacuo. The 4- (4-fluorophenyl) butyloxyamine was obtained as an oil. 250 MHz 1 H NMR (CDCl 3) δ (ppm) = 1.5-1.75 (m, 4H); 2.61 (t, 2H); 3.68 (t, 2H) 5.4 (broad s, 2H); 6.9-7.2 (m, 4H).

4- (4-chlorophenyl) butyloxyamine

<chemistry id="chem0009" num="0009"><img file="EP0456089B1_D0015.tif" /></chemistry>

Analogously to the example described above, starting from N- (4- (4-chlorophenyl) -2-butenyloxyphthalimide (DE-OS 38 38 310), the 4- (4-chlorophenyl) butyloxyamine was obtained as an oil in a total yield of 60%. 250 MHz 1 H NMR (CDCl 3) δ (ppm) = 1.65-1.85 (m, 4H); 2.66 (t, 2H); 4.18 (t, 2H) 7.1-7.4 (m, 5H); M 7.86 (s, 4H).

N- (4- (4-chlorophenyl) butyloxyphthalimide

<chemistry id="chem0010" num="0010"><img file="EP0456089B1_D0016.tif" /></chemistry>

Mp .: 72-73 ° C isopropanol 250 MHz ¹H NMR (DMSO-d₆) δ (ppm) = 1.6-1.85 (m, 4H); 2.68 (t, 2H); 4.17 (t, 2H) 7.2-7.4 (m, 4H); 7.88 (s, 4H).

2- {1- [4- (4-fluorophenyl) butyloximino] butyl} -5-tetrahydrothiopyran-3-yl-3-hydroxy-cyclohex-2-enone (compound 1.04)

A solution of 3 g (11 mol) of 2-butyryl-3-hydroxy-5-tetrahydrothiopyran-3-yl-cyclohex-2-enone in 100 ml of dry methanol was mixed with 2.2 g (12 mmol) of 4- (4- Fluorophenyl) butoxyamine added. The mixture stirred at room temperature for 16 h and was then evaporated to dryness in vacuo. The residue was taken up in diethyl ether and chromatographed on silica gel. Yield: 3.6 g (80% of theory).

According to this specification, the cyclohexenone compounds listed in Table 1 can be obtained.

Examples of use

The herbicidal activity of the cyclohexenoxime ethers of the formula I was demonstrated by greenhouse tests:

Plastic flower pots with loamy sand with about 3.0% humus as a substrate served as culture vessels. The seeds of the test plants were sown separately according to species.

In pre-emergence treatment, the active ingredients suspended or emulsified in water were applied directly after sowing by means of finely distributing nozzles. The tubes were lightly sprinkled to promote germination and growth and then covered with clear plastic hoods until the plants had grown. This cover causes the test plants to germinate evenly, unless this was affected by the active ingredients.

For the purpose of post-emergence treatment, the test plants were treated with the active ingredients suspended or emulsified in water only at a height of 3 to 15 cm, depending on the growth habit. The application rate for post-emergence treatment was 0.06 kg / ha as

The plants were kept at 10-25 ° C and 20-35 ° C depending on the species. The trial period lasted 2 to 4 weeks. During this time, the plants were cared for and their response to the individual treatments was evaluated.

Evaluation was carried out on a scale from 0 to 100. 100 means no emergence of the plants or complete destruction of at least the aerial parts and 0 means no damage or normal growth.

The plants used in the greenhouse experiments are composed of the following types: <tables id="tabl0007" num="0007"><table frame="all"><tgroup cols="3" colsep="1" rowsep="0"><colspec colnum="1" colname="col1" colwidth="52.50mm" /><colspec colnum="2" colname="col2" colwidth="52.50mm" /><colspec colnum="3" colname="col3" colwidth="52.50mm" /><thead valign="top"><row rowsep="1"><entry namest="col1" nameend="col1" align="left">Latvian name</entry><entry namest="col2" nameend="col2" align="center">German name</entry><entry namest="col3" nameend="col3" align="center">English name</entry></row></thead><tbody valign="top"><row><entry namest="col1" nameend="col1" align="left">Orvza sativa</entry><entry namest="col2" nameend="col2" align="left">rice</entry><entry namest="col3" nameend="col3" align="left">rice</entry></row><row><entry namest="col1" nameend="col1" align="left">Echinochloa crus-galli</entry><entry namest="col2" nameend="col2" align="left">Chicken millet</entry><entry namest="col3" nameend="col3" align="left">barnyardgrass</entry></row><row rowsep="1"><entry namest="col1" nameend="col1" align="left">Setaria italica</entry><entry namest="col2" nameend="col2" align="left">Piston millet</entry><entry namest="col3" nameend="col3" align="left">Foxtail Millet</entry></row></tbody></tgroup></table></tables>

With 0.06 kg / ha aS used in the post-emergence process, examples 1.11, 1.03 and 1.05 can be used to combat undesirable grass-like plants very well, while being compatible with the example culture rice.