N-(substituted benzyloxy)imine derivatives, process for the production thereof, use thereof, and method of use thereof

Abstract: Compound of the general formula (I), which is useful as an agricultural and horticultural fungicide, an agricultural and horticultural fungicidal composition containing said compound, use of said composition for controlling plant disease, and process for the production of said compound: shows a case in which R³ and R⁴ together form a cyclic substituent, and R¹ to R⁴ are substituents disclosed in the specification.

Description: This invention relates to N-(substituted benzyloxy)imine derivatives, agricultural and horticultural fungicides containing them as an active ingredient, a process for the production thereof, and a method of controlling plant disease. JP-A-61-106538 and JP-A-61-28045 disclose compounds which are structurally similar to the compound of this invention, and describe that such compounds are useful as an agricultural fungicide or insecticide. However, their activities are not necessarily satisfactory. EP-A-370 629, belonging to the state of the art pursuant to Article 54(3) EPC, discloses compounds of general formula and stereoisomers thereof, wherein A is hydrogen, halo, hydroxy, C₁₋₄ alkyl, C₁₋₄ alkoxy, C₁₋₄ haloalkyl, C₁₋₄ haloalkoxy, C₁₋₄ alkylcarbonyl, C₁₋₄ alkoxycarbonyl, phenoxy, nitro or cyano; R¹ and R², which may be the same or different, are hydrogen, optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted heterocycloalkyl, optionally substituted cycloalkylalkyl, optionally substituted aralkyl, optionally substituted heteroarylalkyl, optionally substituted aryloxyalkyl, optionally substituted heteroaryloxyalkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted alkoxy, optionally substituted aryl. optionally substituted heteroaryl, optionally substituted aryloxy, optionally substituted heteroaryloxy, nitro, halo, cyano, -NR³R⁴, -CO₂R³, -CONR³R⁴, -COR³, -S(O) n R³ wherein n is 0, 1 or 2, (CH₂) m PO(OR³)₂ wherein m is 0 or 1, or R¹ and R² join to form a carbocyclic or heterocyclic ring system; and R³ and R⁴, which may be the same or different, are hydrogen, optionally substituted alkyl, optionally substituted aralkyl, optionally substituted alkenyl, optionally substituted aryl or optionally substituted heteroaryl. These compounds are reported to have fungicidal, insecticidal and miticidal properties. Further compounds of fungicidal activity are described in WO-A-90/07493, also belonging to the state of the art pursuant to Article 54(3). These compounds belong to the general formula wherein X represents an aldimin group or ketimine group, and X specifically represents a group of formula wherein R¹ and R² independently are hydrogen, C₁₋₁₂-alkyl, C₁₋₄-haloalkyl, C₁₋₄-alkoxy-C₁₋₄-alkyl, C₁₋₄-alkylthio-C₁₋₄-alkyl, aryl-C₁₋₄-alkyl, aryloxy-C₁₋₄-alkyl, arylthio-C₁₋₄-alkyl, heteroaryl-C₁₋₄alkyl, C₂₋₁₂-alkenyl, aryl-C₂₋₄-alkenyl, heteroaryl-C₂₋₄-alkenyl, C₂₋₁₂-alkynyl, C₃₋₆-cycloalkyl, aryl, heteroaryl, cyano, COOR³, CONR⁴R⁵, COR⁶ or CR⁷=NOR², wherein R³ to R⁸ each represents hydrogen, C₁₋₄-alkyl, aryl or heteroaryl, or R¹ and R² together with the C-atom to which they are bonded form a 4- to 7-membered ring, optionally containing an O- or S-atom. It is the object underlying the present invention to provide novel compounds having a remarkable fungicidal activity and a process for their production as well as a fungicide containing same compounds and a method for controlling plant disease comprising the use of same compounds. According to the present invention this object is attained with N-(substituted benzyloxy)imine derivatives of general formula (I): wherein R¹ and R² each independently represent a C₁-C₆ alkyl group; one of R³ and R⁴ represents a C₁-C₆ alkyl group, a C₁-C₆ haloalkyl group or a lower alkoxyalkyl group, and the other is a nitrogen atom-containing hetero ring selected from the group consisting of substituted or unsubstituted pyrrolidine, piperidine, morpholine, thiomorpholine, piperazine, hexamethyleneimine, tetrahydroquinoline and tetrahydroisoquinoline, and the nitrogen atom in said hetero ring always forms the bond as a substituent of either R³ or R⁴. According to the present invention there is also provided a process for the production of N-(substituted benzyloxy)imine derivatives of the general formula (I): wherein R¹ and R² each independently represent a C₁-C₆ alkyl group; one of R³ and R⁴ represents a C₁-C₆ alkyl group, a C₁-C₆ haloalkyl group or a lower alkoxyalkyl group, and the other is a nitrogen atom-containing hetero ring selected from the group consisting of substituted or unsubstituted pyrrolidine, piperidine, morpholine, thiomorpholine, piperazine, hexamethyleneimine, tetrahydroquinoline and tetrahydroisoquinoline, and the nitrogen atom in said hetero ring always forms the bond as a substituent of either R³ or R⁴; which comprises reacting a compound of the general formula (II): wherein R¹ and R² are as defined in the above formula (I) and X represents a halogen atom, with a compound of the general formula (III): wherein R³ and R⁴ are as defined in the above formula (I). The present invention further provides an agricultural or horticultural fungicide which comprises an N-(substituted benzyloxy)imine derivative of the present invention in such an amount that exhibits agriculturally or horticulturally fungicidal activity and a carrier acceptable as an agricultural or horticultural inert carrier; and a method of controlling plant disease which comprises applying the agricultural or horticultural fungicide in an amount, as an active ingredient, of 0.1 to 1,000g per 10 ares. The N-(substituted benzyloxy)imine derivative of this invention is present as an isomer having an E-form or Z-form with regard to the carbon-nitrogen double bonds and carbon-carbon double bonds, and these isomers and the mixture of them are included in the scope of this invention. The N-(substituted benzyloxy)imine derivative of this invention can be isolated as a quaternary salt, e.g. as a salt of tosylate. Preferably the hetero-ring in the present N-(substituted benzyloxy)imine derivative is substituted with at least one member, selected from the group consisting of a halogen atom, a C₁-C₆ alkyl group, a phenyl group which may have 1 to 5 substituents selected independently from halogen atoms, benzyl groups, pyridyl groups, pyrimidyl groups and dioxolane groups, particularly with 1 to 3 alkyl groups. It is further preferred that one of R³ and R⁴ is a morpholine group which may be substituted with a C₁-C₆ alkyl group and the other is a C₁-C₆ alkyl group, a C₁-C₆ haloalkyl group or a lower alkoxyalkyl group, especially when the other is a C₁-C₆ alkyl group or a C₁-C₆ haloalkyl group. The N-(substituted benzyloxy)imine derivative of the general formula (I) can be produced by reacting a compound of the general formula (II) with a compound of the general formula (III) in the presence of a base or a silver compound and in the presence of an inert solvent. Any inert solvent that does not prevent the present reaction can be used in this invention. Examples of such a solvent are alcohols such as isopropanol, butanol and diethylene glycol; ketones such as acetone, methyl ethyl ketone and cyclohexanone, ethers such as diethyl ether, diisopropyl ether, tetrahydrofuran, dioxane, monoglyme, diglyme; halogenated hydrocarbons such as a dichloroethane, chloroform, carbon tetrachloride and tetrachloroethane; aromatic hydrocarbons such as benzene, chlorobenzene, nitrobenzene and toluene; nitriles such as acetonitrile; dimethylformamide; dimethylsulfoxide; water and a mixed solvent of these. When a two-phase reaction is carried out in the mixed solvent, a phase transfer catalyst such as, e.g., triethyl-benzylammonium chloride or trioctylmethylammonium chloride can be used. Inorganic bases and organic bases are usable as a base. Examples of the inorganic bases are carbonates of alkali metals or alkaline earth metals such as sodium carbonate, potassium carbonate, calcium carbonate and sodium hydrogencarbonate; hydroxides of alkali metals or alkaline earth metals such as sodium hydroxide, potassium hydroxide and calcium hydroxide; and hydrides of alkali metals such as lithium hydride and sodium hydride. Examples of the organic bases are alkoxides of alkali metal atoms such as sodium methoxide and potassium tert-butoxide, diethylamine, triethylamine, pyridine, and benzyltrimethylammonium hydroxide. As a silver compound, for example, silver oxide can be used. The reaction temperature is suitably between -70°C and the boiling point of the solvent, and it is preferably between -40°C and 30°C. The reaction time varies depending upon the reaction temperature and the reaction scale. It is, in general, from 30 min to 12 h. The present reaction is an equimolar reaction, and a compound of the general formula (II) and a compound of the general formula (III) can therefore be used in equimolar amounts. However, one of these compounds may be used in an excess amount. The base can be used in an equimolar amount based on a compound of the general formula (III). However, it may be used in an excess amount. After completion of the reaction, the intended product is isolated by an ordinary method and, optionally, purified, e.g. by column chromatography or a recrystalization method. The compound of the general formula (II) can be produced according to the process disclosed in JP-A 61-280452. The compound of the general formula (III), the scope of which includes some novel compounds, can be produced according to a process for the production of known compounds [e.g. Org. Syn. Coll. Vol. 2 , 313 (1943), ditto, 363 (1943), and J. Org. Chem., 1980, 45 , 4198]. Table 1 shows typical examples of the N-(substituted benzyloxy)imine derivative of the general formula (I). The following Examples illustrate typical embodiments of the N-(substituted benzyloxy)imine derivative of the general formula (I), Example 1 Methyl 2-[2-{1-(cis-2,6-dimethylmorpholino)-ethylideneaminooxymethylphenyl]-3-methoxyacrylate (Compound No. 15) 1.72 g of 1-(cis-2,6-dimethylmorpholino)-acetoaldoxime was dissolved in 30 ml of dimethylformamide, and 0.66 g of potassium hydroxide powder was added thereto, and the mixture was stirred for 10 min at 0°C. 2.85 g of methyl 2-(2-bromomethylphenyl)-3-methoxyacrylate was added thereto and the resultant mixture was further stirred for 1 h at room temperature to carry out the reaction. After completion of the reaction, the reaction mixture was poured into ice water, and extracted with ethyl acetate. The extracts were washed with water, and dried over magnesium sulfate. The extracts were filtered and concentrated under reduced pressure, and the resultant residue was purified by silica gel dry column chromatography to give 0.4 g of the intended product. Yield: 10.6%, Properties: 107-109°C The N-(substituted benzyloxy)imino derivatives of the general formula (1) are useful as agricultural and horticultural fungicides, and are very effective in controlling various plant diseases such as rice blast ( Pyricularia oryzae), rice sheath blight ( Rhizoctonia solani ), rice brown spot ( Cochliobolus miyabeanus ), powdery mildew of barley ( Frysiphe graminis f.sp. hordei ) and other plants, rust of various plants, and the diseases caused by Oomycetes fungi such as tomato late blight ( Phytophthora infestans ) and cucumber downy mildew ( Pseudoperonaspora cubensis ). The present compounds have excellent compounds have excellent activity in controlling diseases of paddy field crops, upland field crops, fruit trees, vegetables, other crops and flowering plants by the application to crop foliage, irrigation water or soil before or after disease appearance. When the N-(substituted benzyloxy)imine derivative of the general formula (I) is used as an agricultural or horticultural fungicide, it is generally prepared into conveniently usable forms according to an ordinary manner for preparation of agrochemicals. That is, the N-(substituted benzyloxy)imine derivative of the general formula (I) and, optionally, an adjuvant are blended with a suitable inert carrier and prepared into a suitable preparation form such as a suspension, emulsifiable concentrate, soluble concentrate, wettable powder, granules, dust or tablet through dissolution, dispersion, suspension, mixing, impregnation, adsorption or sticking. The inert carrier in this invention may be solid or liquid. Examples of the solid carrier are soybean flour, cereal flour, wood flour, bark flour, saw dust, powdered tobacco stalks, powdered walnut shells, bran, powdered cellulose, extraction residues of vegetables, powdered synthetic polymers or resins, clays (e.g. kaolin, betonite, and acid clay), talcs (e.g. talc and pyrophyllite), silica powders or flakes (e.g. diatomaceous earth, silica sand, mica and white carbon, i.e. synthetic, high-dispersion silicic acid, called finely divided hydrated silica or hydrated silicic acid), activated carbon, powdered sulfur, powdered pumice, calcined diatomaceous earth, ground brick, fly ash, sand, calcium carbonate powder, calcium phosphate powder and other inorganic or mineral powders, chemical fertilizers (e.g. ammonium sulfate, ammonium nitrate, urea and ammonium chloride), and compost. These carriers may be used alone or in combination. The liquid carrier either itself has solubility or is without such solubility but is capable of dispersing an active incredient with the aid of an adjuvant. The following are typical examples of the liquid carriers that can be used alone or in combination. Water; alcohols such as methanol, ethanol, isopropanol, butanol and ethylene glycol; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone and cyclohexanone; ethers such as ethyl ether, dioxane, Cellosolve, dipropyl ether and tetrahydrofuran; aliphatic hydrocarbons such as gasoline and mineral oils; aromatic hydrocarbons such as benzene, toluene, xylene, solvent naphtha and alkylnaphthalene; halogenated hydrocarbons such as dichloroethane, chloroform, carbon tetrachloride and chlorobenzene; esters such as ethyl acetate, diisopropyl phthalate, dibutyl phthalate and dioctyl phthalate; amides such as dimethylformamide and dimethylacetamide; nitriles such as acetonitrile; and dimethyl sulfoxide. The following are typical examples of the adjuvants, which are used depending upon purpose and used alone or in combination in some cases, or may not be used at all. To emulsify, disperse, dissolve and/or wet an active ingredient, a surfactant is used. Examples of the surfactant are polyoxyethylene alkyl ethers, polyoxyethylene alkylaryl ethers, polyoxyethylene higher fatty acid esters, polyoxyethylene resinates, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monooleate, alkylarylsulfonates, naphthalenesulfonic acid condensation products, ligninsulfonates and higher alcohol sulfate esters. Further, to stabilize the dispersion of an active ingredient, tackify it and/or bind it, an adjuvant may be used. Examples of such an adjuvant are casein, gelatin, starch, methylcellulose, carboxymethylcellulose, gum arabic, polyvinyl alcohol, turpentine, bran oil, bentonite and ligninsulfonates. To improve the flowability of a solid product, an adjuvant may be used. Examples of such an adjuvant are waxes, stearates and alkyl phosphates. Adjuvants such as naphthalenesulfonic acid condensation products and polycondensates of phosphates may be used as a peptizer for dispersible products. Adjuvants, e.g. silicone oils, may be also used as a defoaming agent. The content of the active ingredient may be varied as required. In dusts or granules, the suitable content thereof is from 0.1 to 50% by weight. In emulsifiable concentrates, flowable wettable powders, it is from 0.1 to 90% by weight. An agricultural or horticultural fungicide containing the N-(substituted benzyloxy)imine derivative of the general formula (I) as an active ingredient is used to control a variety of crop diseases in the following manner. That is, it is applied to a crop on which diseases are estimated to occur or a site where the occurrence of diseases is undesirable directly or by suitably diluting it with water or suspending it in water in such an amount that is effective to control the diseases. The amount of the agricultural or horticultural fungicide containing the N-(substituted benzyloxy)imine derivative of the general formula (I) as an active ingredient varies depending upon various factors such as a purpose, diseases to be controlled, a growth state of a plant, tendency of diseases occurrence, weather, environmental conditions, a preparation form, an application method, an application site and an application time. It is, however, used in an amount of 0.1 g to 1,000 g per 10 ares as an active ingredient depending upon a purpose. The agricultural or horticultural fungicide containing the N-(substituted benzyloxy)imine derivative of the general formula (I) as an active ingredient may be used as a mixture thereof with an agrochemical, fertilizer and/or plant nutrient which are usable at its application time, or just in combination with these. When the agricultural or horticultural fungicide containing the compound of this invention as an active ingredient is used to control crop diseases, it may be mixed with some other controller(s) to control other crop damage which occurs concurrently with crop diseases to be controlled by the present fungicide, and the mixture can be used as a multi-purpose controller. Examples of such other controllers are as follows. O,O-dimethyl O-(3-methyl-4-nitrophenyl)phosphorothioate (Fenitrothion) O,O-dimethyl O-(3-methyl-4-methylthiophenyl)phosphorothioate (Fenthion) S-α-ethoxycarbonylbenzyl O,O-dimethyl phosphorodithioate (Phenthioate) O,O-diethyl O-(2-isopropyl-6-methyl-4-pyrimidinyl)phosphorothioate (Diazinon) dimethyl 2,2,2-trichloro-1-hydroxyethylphosphonate (Trichlorphon) O-4-cyanophenyl O-ethyl phenylphosphonothioate (Cyanophenphos) O-ethyl O-4-nitrophenyl phenylphosphonothioate (EPN) 4-(methylthio)phenyl dipropylphosphate (Propaphos) O,O-dimethyl S-phthalimidomethyl phosphorodithioate (Phosmet) 2,2-dichlorovinyl dimethyl phosphate (DDVP) O,O-dimethyl S-methylcarbamoylmethyl phosphorodithioate (Dimethoate) S-1,2-bis(ethoxycarbonyl)ethyl O,O-dimethyl phosphorodithiate (Malathion) 1-naphthyl methylcarbamate (Carbaryl) m-tolyl methylcarbamate (Metocarb) 2-isopropoxyphenyl methylcarbamate (propoxur) S-(N-ethoxycarbonyl-N-methylcarbamoylmethyl) O,O-diethylphosphorodithioate (Mecarbam) 3,4-xylyl methylcarbamate (Xylylcarb) 2-sec-butylphenyl methylcarbamate (BPMC) 2-isopropylphenyl methylcarbamate (Isoprocarb) 2-chlorophenyl methylcarbamate (CPMC) 3,5-xylyl methylcarbamate (XMC) 2-(1,3-dioxolan-2-yl)phenyl methylcarbamate (Dioxacarb) 3-tert-butylphenyl methylcarbamate (Terbam) 4-diallylamino-3,5-xylyl methylcarbamate (Allyxycarb) S-methyl N-(methylcarbamoyloxy)thioacetimidate (Methomyl) N-(4-chloro-o-tolyl)-N,N-dimethylformamidine hydrochloride (Chlorodimeform) 1,3-bis-(carbamoylthio)-2-dimethylaminopropane hydrochloride (Cartap) Diisopropyl 1,3-dithiolan-2-ylidenemalonate (Isoprothiolane) S-benzyl O,O-diisopropyl phosphorothioate (IBP) TEST EXAMPLES Test Example 1. Controlling effect on powdery mildew of barley ( Erysiphe graminis f.s. hordei ) Barley seedlings at 2-leaf stage were sprayed with the test compound (200 ppm) one day after inoculation with conidia of Erysiphe graminis f.sp. hordei . The seedlings were held in a constant-temperature room at 25°C for one week and the percentage of the infected area per leaf was examined. Disease controlling activity was estimated in comparison with the untreated plot as follows. A: control rate 100-95% B: control rate 94-80% C: control rate 79-60% D: control rate 59-0% Table 2 shows the results Test example 2. Controlling effect on downy mildew of cucumber ( Pseudoperonospora cubensis ) Cucumber plants at 2-leaf stage were sprayed with the test compound (200 ppm) one day before inoculation with zoospores of Pseudoperonospora cubensis . After the plants were held in a humid room at 25°C for one day and then in a greenhouse for 6 days, the degree of infection per leaf was examined. Disease controlling activity was estimated in the same manner as in Test example 1. The results are shown in Table 3. Test example 3. Controlling effect on rice blast ( Pyricularia oryzae ) Rice seedlings at 5-leaf stage were sprayed with the test compound (200 ppm) one day before inoculation with conidia of Pyricularia oryzae . After the seedlings were held in a humid room at 25°C for one day and then held in a greenhouse for 6 days, the number of lesions appeared per leaf was examined. Disease controlling activity was estimated in the same manner as in Test example 1. The results are shown in Table 4.

Claims: N-(substituted benzyloxy)imine derivatives of general formula (I): wherein R¹ and R² each independently represent a C₁-C₆ alkyl group; one of R³ and R⁴ represents a C₁-C₆ alkyl group, a C₁-C₆ haloalkyl group or a lower alkoxyalkyl group, and the other is a nitrogen atom-containing hetero ring selected from the group consisting of substituted or unsubstituted pyrrolidine, piperidine, morpholine, thiomorpholine, piperazine, hexamethyleneimine, tetrahydroquinoline and tetrahydroisoquinoline, and the nitrogen atom in said hetero ring always forms the bond as a substituent of either R³ or R⁴. The N-(substituted benzyloxy)imine derivatives of claim 1, wherein the hetero ring is substituted with at least one member, selected from the group consisting of a halogen atom, a C₁-C₆ alkyl group, a phenyl group which may have 1 to 5 substituents selected independently from halogen atoms, benzyl groups, pyridyl groups, pyrimidyl groups and dioxolane groups. The N-(substituted benzyloxy)imine derivatives of claim 2, wherein the hetero ring is substitued with 1 to 3 alkyl groups. The N-(substituted benzyloxy)imine derivative of claim 1, wherein one of R³ and R⁴ is a morpholine group which may be substituted with a C₁-C₆ alkyl group and the other is a C₁-C₆ alkyl group, a C₁-C₆ haloalkyl group or a lower alkoxyalkyl group. The N-(substituted benzyloxy)imine derivative of claim 4, wherein the other is a C₁-C₆ alkyl group or a C₁-C₆ haloalkyl group. A process for the production of N-(substituted benzyloxy)imine derivatives of the general formula (I): wherein R¹ and R² each independently represent a C₁-C₆ alkyl group; one of R³ and R⁴ represents a C₁-C₆ alkyl group, a C₁-C₆ haloalkyl group or a lower alkoxyalkyl group, and the other is a nitrogen atom-containing hetero ring selected from the group consisting of substituted or unsubstituted pyrrolidine, piperidine, morpholine, thiomorpholine, piperazine, hexamethyleneimine, tetrahydroquinoline and tetrahydroisoquinoline, and the nitrogen atom in said hetero ring always forms the bond as a substituent of either R³ or R⁴; which comprises reacting a compound of the general formula (II): wherein R¹ and R² are as defined in the above formula (I) and X represents a halogen atom, with a compound of the general formula (III): wherein R³ and R⁴ are as defined in the above formula (I). An agricultural or horticultural fungicide which comprises an N-(substituted benzyloxy)imine derivative of any of claims 1 to 5 in such an amount that exhibits agriculturally or horticulturally fungicidal activity and a carrier acceptable as an agricultural or horticultural inert carrier. A method of controlling plant disease which comprises applying an agricultural or horticultural fungicide of claim 7 in an amount, as an active ingredient, of 0.1 to 1,000 g per 10 ares.

Inventors: ENDO KATSUTOSHI, KANNO HIDEO, NIINO NOBUYUKI, TSUBATA KENJI, YAMAMOTO YOSHINOBU, ENDO, KATSUTOSHI, KANNO, HIDEO, NIINO, NOBUYUKI, TSUBATA, KENJI, YAMAMOTO, YOSHINOBU
Applicants: NIHON NOHYAKU CO LTD, NIHON NOHYAKU CO., LTD.
Application year: 1990
Main classification: C07C251
IPC codes: A01N57, C07D339, C07D209, C07F9, C07D265, C07D249, C07D295, A01N47, C07D239, A01N41, A01N43, A01N37, C07C323, C07C251, C07D317, C07C255, C07D307, C07C317, C07D335, C07D211, C07D213, C07D333, C07C257, C07D309, C07C327, C07D207, C07D491, C07D241, C07D231, C07D311, C07C311, C07D215, C07D521