GB2093448A - Acylated hydrazine carboxylates - Google Patents

Abstract

The invention provides novel 2- acylated 1-C1-4alkyl-2-phenyl- hydrazine carboxylates, e.g. methyl 1- methyl-2-(methoxyacetyl)-2-(2,6- dimethylphenyl)-hydrazine- carboxylate, which are useful as fungicides. Other aspects of the invention are fungicidal compositions comprising such novel compounds, methods of combatting phytopathogenic fungi with the aid of said novel compounds, and the preparation of such novel compounds and fungicidal compositions.

Description

SPECIFICATION Improvements in or relating to organic compounds The present invention provides compounds useful in the combatting of phytopathogenic fungi.

More specifically the present invention provides compounds 5 of formula I

wherein R1 is H, C1-4alkyl, halogen or C1-4alkoxy, R2 is C,~4alkyl, halogen or C,~4alkoxy, R3 is hydrogen, C,~4aikyl or halogen, R4 is C1-4alkyl, R5 is C1-4alkyl unsubstituted or substituted by halogen, CN or SCN, R6 is H; Alkyl or C2~6alkenyl unsubstituted or substituted by halogen; C2~6alkinyl; C3~7cycloalkyl; C3-7cycloalkyl-C1-3alkyl; C2~6epoxyalkyl;; phenyl, phenyl-C1-3alkyl or phenyl C2~3alkenyl wherein the aromatic moiety is unsubstituted or substituted by 1 to 3 substituents selected from the group consisting of C1~4alkyl, C1~4alkoxy, halogen, NO2, phenyl or phenoxy; C1-4alkoxy-C1-4alkyl; C1-4alkylthio-C1-4alkyl; 2-furyl; 2-tetrahydrofuryl; halogenated 2-furyl; halogenated 2-tetrahydrofuryl; 1-imidazoylmethyl; 1-pyrrazolylmethyl; 2 tetra hydrofuryloxymethyl; 2-tetrahydropyranyloxymethyl.

When any of R1, R2 or R3 is or includes an alkyl group (e.g. alkoxy), this is preferably C1~4alkyl, i.e.

methyl, ethyl, n-propyl or i-propyl.

When any of Rr, R2, R3, R5 or R8is or includes halogen, this is F, Cl, Br or I, preferably F, Cl or Br, more preferably Cl or Br, particularly Cl.

R, and R2 are preferably in the 2- and the 6-position of the 5 phenyl group to which they are bound.

R3 is preferably Cl or Br.

R4 is preferably C,~3alkyl, more preferably C,~2alkyl, particularly OH 3.

When R5 is substituted Alkyl it is preferably mono-substituted.

The C1-4alkyl group of R5 is preferably a C1-3alkyl group, more preferably C1~2alkyl, particularly CH3.

Preferred C1-6alkyl significances of R6 are C24alkyl, particularly C3alkyl.

Preferred C2-6alkenyl significances of R6 are C24alkenyl, particularly C3alkenyl.

Preferred C37cycloalkyl significances of R6 are C3-6cycloalkyl, particularly C3-4cycloalkyl.

Preferred halogenated 2-furyl significances of R6 are mono-halogenated 2-furyl, e.g. 5-chloro-2furyl and 5-bromo-2-furyl.

Preferred C1-4halogenalkyl significances of R6 are C1~4chloroalkyl, or C1-4bromoalkyl, e.g.

chloromethyl, bromomethyl and C2H 5CHBr.

Preferred halogenated 2-tetrahydrofuryl significances of R6 are mono-halogenated 2tetrahydrofuryl, particularly mono-chlorinated or mono-brominated 2-tetrahydrofuryl e.g. 5-chloro-2tetrahydrofuryl.

Preferred C,~4alkoxy-C~4alkyl significances of R6 are C1~3alkoxymethyl, particularly CH3OCH2- and C2H5OCH2-.

Preferred C1-4alkylthio-C1-4alkyl significances of R6 are C1~3alkylthiomethyi, e.g. CH3SCH2.

R6 is preferably C1~6alkyl, C26alkenyl, C37cycloalkyl, C1-4alkoxy-C1-4alkyl, 2-furyl or 5-halo-2- furyl, more preferably C14alkoxy-C14alkyl.

R1 is preferably in the 2-position, R2 preferably in the 6-position and R3 preferably in the 3- position.

Thus, a preferred group of compounds are the compounds of formula la

wherein R,' and F2, independently are CH3, Cl or Br, R3, is H, Cl, Br or CH3, R5' is C 14alkyl and R6' is CH20CH3, CH20C2H5, 2-furyl or 5-halo-2-furyl.

Particularly preferred meanings of F6, are CH20CH3 or CH20C2H5.

According to a further aspect of the invention the compounds of formula I are produced by Nalkylating a compound of formula

wherein R1, R2, R3, R5 and R6 are as defined above, with an alkylating agent of formula III R4X, 111 wherein R4 is as defined above, and X, is a leaving group displaceable under the N-alkylation reaction conditions.

The N-alkylation of the invention can be carried out in a conventional manner. Suitable alkylating agents are for example the corresponding alkylhalogenides, particularly the alkyliodides, alkyl esters of sulphonic acids, e.g. methane sulphonic acid esters (mesylates) or tosylates, or dialkylsulphates, e.g.

dimethylsulphate. The compound of formula 11 is conveniently used in its salt form, e.g. in its N-alkali metal salt form, particularly its Na- or K-salt form which may be obtained by reacting the compound of formula 11 with a strong base, e.g. an alkali metal hydride, amide or alcoholate in a solvent which is inert under the reaction conditions, e.g. a hydrocarbon such as toluene. Such salts are suitably prepared with heating, preferably at reflux temperature. The N-alkylation of the invention may then be carried out by adding to the reaction mixture comprising the compound of formula 11 in salt form, an alkylating agent, e.g. C,~4alkyliodide. Preferably the alkylating agent is used in excess.The N-alkylation is suitably carried out with heating e.g. at a temperature of from 80 to 1 500C.

The compounds of formula I may be recovered from the reaction mixture in which they are formed by working up by established procedures.

The compounds of formula II are novel. They may be obtained by acylation of compounds of formula IV

wherein F1, R2, R3 and R5 are as defined above, with a compound of formula V

wherein R6 is as defined above, and Z is halogen, particularly CI, or OCOR6 wherein R6 is as defined above.

Suitable solvents for this acyiation reaction arehydrncarbonssuch as chlorobenzene. The reaction is conveniently effected at a temperature of from about 0 to about 1200C, e.g. room temperature, optionally in the presence of a base as e.g. triethylamine or pyridine.

The compounds of formula IV may be obtained by reaction of compounds of formula VI

wherein R,, R2 and R3 are as defined above, with a compound of formula VII

wherein R5 is as defined above, and X2 is halogen, particularly Cl.

This reaction is for example effected at a temperature of from about 0 to about 4O0C, conveniently at room temperature, in water or in an organic solvent which is inert under the reaction conditions, conveniently in the presence of a base, e.g. an organic amine or sodium hydrogen carbonate.

The starting materials and reagents employed in the processes described above are either known or, insofar as they are not known, they may be produced in analogous manner to the processes described herein or to known processes.

The compounds of formula I have useful fungicidal activity, particularly against phytopathogenic fungi, especially against fungi of the class Oomycetes as indicated by a significant fungicidal effect in tests against Phytophtora infestans in potatoes (test description, see Test A hereinafter) and against Plasmopara viticola in grape vine (test description, see Test B hereinafter) with test concentrations of 8 ppm to 125 ppm, e.g. 8 ppm, 32 ppm and 125 ppm. Representative compounds show also interesting activity against Pythium aphanidermatum after soil treatment with concentrations of 10 to 1 60 ppm, e.g. 32 and 125 ppm (see Test C hereinafter).The compounds of formula I are essentially nonphytotoxic at fungicidally effective doses in plants subject to such fungi and are further indicated to be of particular interest for combatting fungi by systemic, curative and eradicative action (Test D, E and F hereinafter).

Test A: Fungicidal effect against Phytophthora infestans Young potted potato plants (3-5 leaf stage) are sprayed until the run off with an aqueous spray suspension containing 0.01% to 0.0008% (weight/volume) of a compound of formula I, formulated for example in accordance with Formulation Example I hereinafter. Two hours later, the treated plants are inoculated with a spore suspension of Phytophthora infestans (approx. 105 sporangia/ml) and the plants are then transferred to a tent providing 100% relative atmospheric humidity at an ambient temperature of 160C and 1 6 hours daylight/day.Disease control is evaluated 4-5 days later by comparing the treated plants with untreated, similarly inoculated plants. (Test results of representative compounds see Table I hereinafter).

Test B: Fungicidal effect against Plasmopara viticola Young potted plants of grape vine (3-6 leaf stage) are sprayed until the run off with an aqueous spray suspension containing 0.01% to 0.0008% (weight/volume) of a compound of formula I formulated for example in accordance with Formulation Example I hereinafter. Two hours later, the treated plants are inoculated by spray application to the plant of a spore suspension of about 105 sporangia/ml of Plasmopara viticola and the plants are then transferred to a tent providing 100% relative atmospheric humidity at an ambient temperature of 1 5--220C (fluctuating over a 24 hr-period) and 1 6 hours daylight/day. Disease control is evaluated 6 days after inoculation by comparing the treated plants with untreated, similarly inoculated plants. (Test results of representative compounds see Table I hereinafter).

TABLE I

l FUNGI FUNGICIDAL EFFECT IN % CONTROL(1) \ ppm Test A Test B Compound L 125 32 8 125 32 8 x 1 90 70 20 90 70 30 2-3 50 -(2) - 50 - 26 100 - - - - 2-14 80 40 20 100 100 60 2-22 50 - - 50 - 35 50 - - - - 36 70 - - 80 70 50 37 90 70 20 100 100 50 (1)visual determination, 100% is complete control of disease and 0% is no control of disease.

2 ( )not tested Test C: Soll Treatment In vivo, employing Pythium aphanidermatum. The fungus is cultivated in a sterile mixture of sand and corn meal (97:3 v/v), to which water is added in a ratio of about 1:4 (v/v); cultivation lasts for 4 days at 250C. The fungus is then mixed into a semi-sterile mixture of peat and sand which then is treated with a suspension containing the formulated active ingredient to give concentration of 10 to 160 ppm (e.g.

10, 40 and 1 60 ppm) calculated per volume substrate) The substrate is transferred to pots of 5 cm diameter which are seeded with cucumber seeds. The planted pots are incubated at 240C and 6070% relative humidity in an incubation chamber for 7 days, after which disease attack is evaluated by a visual determination of the number of healthy emerged plants compared with that in untreated, similarly inoculated check pots. The compound of Example I, hereinafter, used in accordance with Formulation Example I hereinafter, provides a disease control of 90% with a test concentration of 1 25 ppm and of 80% with a test concentration of 32 ppm.

Tests analogous to Test C give similar results with peas and sugar beets.

Test D: Translocation in treated leaves of grape vines Excised leaves of grape vine are treated with an aqueous spray suspension containing 0.012% of a compound of formula I, e.g. methyl 1 -methyl-2-methoxyacetyl-2-(2,6-dimethylphenyl)-hydrazine- carboxylate (formulated in accordance with Formulation Example I), in that only the lower half of such leaves is treated. Two hours after treatment, the whole leaf is inoculated with a spore suspension of Plasmopara viticola after which the leaves are incubated in a tent providing 100% atmospheric humidity at conditions as described in Test B. Although only the lower half of the leaves was treated as stated above, with the test compound substantial disease control on the entire inoculated leaf was observed.

The same effect was also observed, when only the upper half of the leaves was treated. This test thus shows, that the methyl 1 -methyl-2-methoxyacetyl-2-(2,6-dimethylphenyl)-hydrazine-carboxylate (formulated in accordance with Formulation Example I), is distributed within a leaf both acropetally and basipetally.

Test E: Curative fungicidal effect against Plasmopara viticola Young potted plants of grape vine (3-6 leaf stage) are inoculated in the same way as determined in Test B, but the application of the compound, e.g. methyl 1 -methyl-2-methoxyacetyl-2-(2,6- dimethylphenyl)-hydrazine-carboxylate (formulated in accordance with Formulation Example I), follows only after 3 days after inoculation; the incubation conditions are the same as described in Test B.

Disease control is evaluated as stated in Test B. With the test compound, substantial control of the fungal infection is observed.

Test F: Eradicative fungicidal effect against Plasmopara viticola The procedure to evaluate this kind of activity is evaluated as described in Test E, with the exception that the treatment is carried out only 6 days after inoculation when sporulation on the lower leaf surface is already evident. Disease control is evaluated 7 days after application of the spray liquid.

With e.g. 0.012% of the compound methyl 1-methyl-2-methoxyacetyl-2-(2,6-dimethylphenyl)- hydrazinetcarboxylate (formulated in accordance with Formulation Example I), a stopping effect on already sporulating zones is observed.

Particularly effective fungicidal activity is found in the above tests with the compounds of formula la wherein Rtr and R'2 are OH R'3 is H, 3-CI or 3-Br; R5' is CH3 and R6, is CH20CH3.

The compounds of the invention of formula I are therefore indicated for use as fungicide.

The invention therefore also provides a method of combatting phytopathogenic fungi, especially of the class Oomycetes, in plants, seeds or soil with a fungicidally effect amount of a compound of formula I.

Fungi of the class Oomycetes, against which the method of the invention is indicated to be particularly effective, are those of the genus Phytophthora in plants such as potatoes, tomatoes, tobacco, citrus, cacao, rubber, apples, strawberries, vegetables and ornamentals, e.g. Phytophthora infestans in potatoes and tomatoes; of the genus Plasmopora in plants such as grape vines and sunflower e.g. Plasmopara viticola in grape vines; of the genus Peronospora in plants such as tobacco, e.g. Peronospora tabacina in tobacco; of the genus Pseudoperonospora in plants such as hops and cucumber, e.g. Pseudoperonospora humuli in hops; of the genus Bremia in plants such as lettuce, e.g.

Bremia lactucae in lettuce; of the genus Pythium causing damping-off and root rots in a great number of plants, such as vegetables, sugar beets, ornamentals and conifers, e.g. Pythium aphanidermatum in sugar beets; of the genus Sclerospora in plants such as sorghum and corn, e.g. Sclerospora sorghis in sorghum.

For use in the method of the invention, the amount to be employed will vary depending on such factors as the species of fungi to be combatted, the time and nature of application and the amount and nature of the compound of formula I employed.

However, in general, satisfactory results are obtained when applied to a locus, e.g. on crops or to soil with a dosage rate in the range of from 0.05 to 5 kg, preferably from 0.1 to 3 kg particularly from 0.1 to 0.5 kg of a compound of formula I/ha treated locus, the application being repeated as required.

When employed as a seed dressing, satisfactory results are obtained when applied at a rate of from about 0.05 to 0.5, preferably about 0.1 to 0.3 g compound of formula I/kg seed.

Depending on the circumstances, the compounds of formula I may be used in association with other pesticides e.g. fungicides, bactericides, insecticides, acaricides, herbicides or plant growth regulating agents in order to enhance their activity or to widen their spectrum of activity.

Fungicides particularly indicated for use in association with a compound of formula I are one or more compounds selected from a copper fungicide, captan, folpet, mancozeb or maneb.

Examples of copper fungicides suitable for use in association with a compound of formula I are e.g.

copper (II) carbonat, copper (II) calcium sulphate, copper (II) calcium oxychloride, tetracupric oxychloride, Bordeaux mixture, Burgundy mixture, cuprous oxide, cupric hydroxide, copper (II) oxychloride or also copper complexes such as copper triethanolamine hydroxide of the formula [Cu N(OH2OH2OH)3]-(OH)2, or bis(ethylenediamine)-copper (II) sulphate of the formula [Cu(H2NCH2CH2NH2)2]SO4, and mixtures thereof, particularly cuprous oxide, copper (II) oxychloride, cupric hydroxide and a mixture of copper (II) calcium sulphate and copper (II) oxychloride.

Captan, Folpet, Mancozeb and Maneb are the common names for protective fungicides effective against foiiage diseases (Pesticide Manual, 5th Ed., by H. Martin and C. R. Worthing, page 76,281,328 and 329 resp.).

The compounds of formula I are conveniently employed as fungicidal compositions in association with agriculturally acceptable diluents. Such compositions also form part of the present invention They may contain, aside from a compound of formula I as active agent, other active agents, such as fungicides. They may be employed in either solid or liquid forms e.g. in the form of a wettable powder, an emulsion concentrate, a water dispersible suspension concentrate ("fiowable"), a dusting powder, a granulate,a delayed release form, incorporating conventional diluents. Such compositions may be produced in conventional manner, e.g. by mixing the active ingredient with a diluent and optionally other formulating ingredients such as surfactants.

The term diluents as used herein means any liquid or solid agriculturally acceptable material which may be added to the active constituent to bring it in an easier or improved applicable form, respectively to a usable or desirable strength of activity. It can for example be talc, kaolin, diatomaceous earth, xylene, or water.

Particularly formulations to be applied in spraying forms such as water dispersible concentrates or wettable powders may contain surfactants such as wetting and dispersing agents, e.g. the condensation product of formaldehyde with naphthalene sulphonate, an alkylarylsulphonate, a lignin sulphonate, a fatty alkyl sulphate, an ethoxylated alkylphenol and an ethoxylated fatty alcohol.

In general, the formulations include from 0.01 to 90% by weight of active agent from 0 to 20% fungicidally acceptable surfactant and 0.01 to 10% solid or liquid diluent(s), the active agent consisting either of at least one compound of formula I or mixtures thereof with other active agents, such as fungicides. Concentrate forms of compositions generally contain between about 2 and 80%, preferably between about 5 and 70% by weight of active agent. Application forms of formulation may for example contain from 0.01 to 20% by weight, preferably from 0.01 to 5% by weight of active agent.

The invention is illustrated by the following Examples wherein parts and percentages are by weight and temperatures are in 00.

FORMULATION EXAMPLE 1 Wettable powder 50 Parts of methyl 1 -methyl-2-(methoxyacetyl)-2-(2,6-dimethylphenyl)-hydrazine-carboxylate are ground with 2 parts of lauryl sulphate, 3 parts sodium lignin sulphonate and 45 parts of finely divided kaolinite until the mean particle size is below 5 microns. The resulting wettable powder so obtained is diluted with water before use to a concentration of between 0.01% to 5% active agent.

The resulting spray liquor may be applied by foliar spray as well as by root drench application.

FORMULATION EXAMPLE 2 Granulate 0.5 Parts by weight of a binder (non-ionic tenside) is sprayed onto 94.5 parts by weight of quartz sand in a tumbler mixer and the whole thoroughly mixed. 5 Parts by weight of powdered methyl 1 methyl-2-(methoxyacetyl)-2-(2,6-dimethylphenyl)-hydra-zine-carboxylate are then added and thoroughly mixing continued to obtain a granulate formulation with a particle size in the range of from 0.3 to 0.7 mm. The granulate may be applied by incorporation into the soil adjacent the plants to be treated.

FORMULATION EXAMPLE 3 Emulsion Concentrate 25 Parts of a compound of formula I, e.g. the compound of Example 1, hereinafter given, 65 parts of acetone, 1 0 parts of the reaction product of an alkylphenol with ethyleneoxide and calciumdodecylbenzene sulphonate are thoroughly mixed until a homogeneous solution is obtained. The resulting emulsion concentrate is diluted with water before use.

EXAMPLE 1 Methyl 1 -methyl-2-(methoxyacetyl)-2-(2,6-dimethylphenyl)-hydrazine-carboxylate 0.73 g (0.03 Mol) NaH and 7.82 g (0.03 mol) methyl 2-(methoxyacetyl)-2-(2,6-dimethylphenyl)hydrazine-carboxylate in 100 ml absolute toluene are heated under reflux during 3 hours. The reaction mixture is then, together with 9.52 g (0.067 mol) Cm31, transferred into a sealed cylinder and heated 20 hours at 1100. The mixture is then diluted with diethylether, washed with water, dried, concentrated by evaporation and chromatographed over silica gel (eluant CHCI3:acetone 9:1). The title compound is obtained as an oil which crystallizes from diethylether:petrol ether, m.p. 72--40.

EXAMPLE 2 Following the procedure of Example 1, but employing the appropriate compounds of formula II and alkyliodides as alkylating agents, the following compounds are obtained (Table A). Where the compound is obtained as an oil, the compound is characterised by its RF value on silica gel, whereby a), b), c), d), e), f) and g) specify the mobile phase used, which is for a) n-hexane:ethylacetate 1:1, for b) nhexane:ethylacetate 1 :2, for c) n-hexane:ethylacetate 2:1, ford) n-hexane:ethylacetate 1 :3, for e) nhexane:acetone 4:1 ,for f) chloroform acetone 9:1 and for g) diethylether.

TABLE A

Charac teri zation Ex. Rl R2 R3 R4 R5 R6 m.p./Rf CH3 2-1 2-CH3 6-CH3 H CH3 CHz -CH2OCH3 0.32/f) CH3 'eCHa 2-2 ,, ,, ,, 55 -CH2CH a, 0.18/e) CH3 2-3 ,, 5, .. ,, -CH3 < 97-99' CH, 2 < .. ., .. CH, CH3 1331350 2-7 ,, CHa ,, sa ,, -CH2OCH3 0.2/a) 2-8 ,, H ,, .. ,, -CH2OCH3 0.24/b) 2-9 ,, ,, .. 55 .r -CHOO2H5 0.18/a) 2-10 ,, .. ,, ,5 ,, 0.24/a) 211 ,, '5 ,, C2H5 ,, -CH2OCH3 0.25/b) 2-12 ,, .. ,, ,, ,I -CH2OC2H5 0.25/a) 2-13 ,, .. 5, ,, .. 110-112" 2-14 ,, 3-CI 6-CH3 CH3 ,, -CH2OCH3 0.18/a) 215 2-C,H, 4-Cl 8-C2H5 ,, .. .. 0.35/9) 2-16 ,, . . ,, .. . . lCH2oC2H5 0.28/a) 2-17 ,, .. ,, 5, .. 108-110" TABLE A (Continued)

Charac teri sati on Ex. R, R2 R3 R4 Rs R6 m.p./Rf 2-18 2-C,H, 4-Cl 6-O2H, -OH3 CH3 0.31/a) 2-19 ,, .. ,, -O2H5 rr -CH2OCH3 0.24/a) 2-20 ,, 5, 5, .. 5,, -CH2OC2H5 0.34/a) 2-21 ,, ., ., 5, ,, < 109-111" 2-22 2-OCH3 H H -OH3 ,, -SH,OCH, 0.09/a) 2--23 ,, ,I ,, II ,, 128-130' 2-24 ,, ,, II rl 1, -r\ 0.2/d) 2-25 ,, " 5, 5, CH2 -CH,- r? 0.28/a) 2-26 3-CF3 ,, , 5, 5, -CH2OCH3 0.13/a) 2-27 ,, . . " 55 0.29/a) 2-28 ,, II ,, It I, 0.21/a) 2-29 " " " ., ., SH2 < 0.37/a) 2-29 ,, ,1 ,1 ,, II 1H/9 0.37/a) 2-30 2-Cl 4-Cl 6-Cl ,, " -OH2OOH3 0.32/a) 2-31 ,, .. 1, 5, 5, 162-165" TABLE A (Continued)

I 1 teri sation Ex. R, R2 R3 R4 Ra, m.p./Rf 2-32 2-CI 4-CI 6-CI -CH3 CH3 --r) 0.28/a) 2-33 ,, " ,, .. 55 uCH2 0.30/c) 2-34 2-OH3 6-OH3 H CH3 CH3 CH2CH2CH3 0.33/a) 2-35 ,, 55 -5, 55 ., CH2=CHCH3 87-90" 246 ,, -3-Br 8-OH3 ,, .. CH=OHOH3 0.1 8/a) 2-37 ,, 5, " ,t 5, CH2OCH3 0.22/a) 248 " " " .. ,. CH2CH2CH3 0.44/b) 239 x CH3 H ~ .. CH2 ' on5/U INTERMEDIATES EXAMPLE A Methyl 2-(2 ,6-dimethylphenyl)-hydrazinecarboxylate To a mixture of 34 g (0.25 mol) 2,6-dimethylphenylhydrazine, 27.6 g (0.35 mol) pyridine and 83 ml water are added dropwise, within 15 minutes, at room temperature, 23.6 g (O.25 mol) chloroformic acid methyl ester. Thereto are added 83 ml water and this mixture is stirred 3 hours at room temperature. After the addition thereto of diethylether, the reaction mixture is acidified with 2N HCI, the organic phase washed with water, dried and concentrated. The solid residue crystallizes from diethylether/petroleum ether, m.p. 80--810.

EXAMPLE B Methyl 2-(methoxyacetyl)-2-(2,6-dimethylphenyl)-hydrazine-carboxylate To a solution of 1 6.9 g (0.087 mol) methyl 2-(2,6-dimethylphenyl)-hydrazine-carboxylate in 11 5 ml absolute toluene are added dropwise, within 20 minutes, 10.4 g (0.096 mol) methoxyacetyl chloride. The suspension is stirred during 3 days at room temperature, the solvent then evaporated off and the solid residue crystallized from acetone-petroleum ether; m.p. 171--1720.

Claims (9)

1. A compound of formula I

wherein R1 is H, C1-4alkyl, halogen or C1-4alkoxy, R2 is C,~4alkyl, halogen or C1~4alkoxy, Ra is hydrogen, Alkyl or halogen, R4 is C,~4alkyl, R5 is Alkyl unsubstituted or substituted by halogen, CN or SCN, R6 is H; C 15alkyl or C2~6alkenyl unsubstituted or substituted by halogen; C2~6aikinyl; C3~7cycloalkyl; C3-7cycloalkyl-C1-3alkyl; C2~6epoxyalkyl;; phenyl, phenyl-C,~3alkyl or phenyl C2~3alkenyl wherein the aromatic moiety is unsubstituted or substituted by 1 to 3 substituents selected from the group consisting of C,~4alkyl, C,~4alkoxy, halogen, NO2, phenyl or phenoxy; C1-4alkoxy-C1-4alkyl; C1-4alkylthio-C1-4alkyl; 2-furyl; 2-tetrahydrofuryl; halogenated 2-furyl; halogenated 2-tetrahydrofuryl; 1-imidazoylmethyl; 1-pyrrazolylmethyl; 2 tetra hydrofuryloxymethyl; 2-tetrahydropyranyloxymethyl.

2. A compound according to Claim 1 of formula la

wherein R,' and R2, independently are CH3, CI or Br, R3, is H, CI, Br or CH3, R5' is C,~4alkyl and R6' is CH2OCH3, CH2OC2H5, 24uryl or 5-halo-2-furyl.

3. A compound according to Claim 2, selected from the group consisting of compounds wherein R,', R2', R3,, R5' and R6' are a) CH3, CH3, H, CH3 and CH2OCH3 respectively, b) CH3, CH3, 3-CI, CH3 and CH2OCH3 respectively, c) CH3, CH3, 3-Br, CH3 and CH2OCH3 respectively.

4. A process for the production of a compound of formula I, defined in Claim 1,which comprises N-alkylating a compound of formula Il

wherein R1,R2,R3,R5 and R6 are as defined in Claim 1 with an alkylating agent of formula Ill R4X1 Ill wherein R4 is as defined in Claim 1 and X, is a leaving group displaceable under the N-alkylation reaction conditions.

5. A compound of formula I as defined in Claim 1, wherever obtained by a process claimed in Claim 4.

6. A fungicide, comprising a compound claimed in any one of Claims 1 to 3 and 5, and an agriculturally acceptable diluent.

7. A process for the preparation of a fungicide as claimed in Claim 6, characterised in that an agriculturally acceptable diluent is mixed with a compound of any one of Claims 1 to 3 and 5.

8. The use of a compound of any one of Claims 1 to 3 and 5 as fungicide.

9. The use according to Claim 8 against phytopathogenic fungi of the class Oomycetes.

1 0. The use according to Claim 9 of the compounds defined in Claim 3 against fungi of the genera Phytoph thora, Plasmopora or Peronospora.