WO1998035964A1

WO1998035964A1 - Benzoxazinyl-heterocycles with herbicidal activity

Info

Publication number: WO1998035964A1
Application number: PCT/EP1998/000651
Authority: WO
Inventors: Giovanni Meazza; Franco Bettarini; Piero La Porta; Sergio Massimini; Ernesto Signorini; Domenico Portoso
Original assignee: Isagro Ricerca SRL
Current assignee: Isagro Ricerca SRL
Priority date: 1997-02-12
Filing date: 1998-02-04
Publication date: 1998-08-20
Anticipated expiration: 1999-08-12
Also published as: ITMI970275A1; IT1289618B1

Abstract

Benzoxazinyl-heterocycles having general formula (I). The above benzoxazinyl-heterocycles have a high herbicidal activity.

Description

BENZOXAZINYL-HETEROCYCLES WITH HERBICIDAL ACTIVITY -

The present invention relates to benzoxazinyl- heterocycles .

More specifically, the present invention relates to benzoxazinyl-heterocycles having a high herbicidal activity, a process for their preparation and their use as herbicides for the control of weeds in agricultural crops.

Benzoxazinyl-heterocycles having a herbicidal activity are described, among others, in U.S. patents 4.640.707, 4.761.174, 4.798.620, 4.877.444 and 4.902.335.

In particular, U.S. patent 4.640.707 describes the compound corresponding to N- (7-fluoro-3 , 4-dihydro-3- oxo-4-prop-2-inyl-2H-l , 4—benzoxazin-6-yl) cyclohex-1- ene-1, 2-dicarboximide. This product, however, when applied in post-emergency, is highly phytotoxic with respect to all the most important agricultural crops and cannot therefore be used in the above applications. The Applicant has now found that, by suitably modifying the substituent in position 4 of the benzoxa- zinone ring, compounds are obtained which, as well as having a high herbicidal activity with respect to numerous weeds, at the same time have a low phytotoxic- ity with respect to one or more crops of agrarian interest even when used in post-emergency treatment. As a result, these compounds can be used as selective herbicides in either pre- and post-emergency treatment. The present invention therefore relates to benzoxazinyl-heterocycles having general formula (I) :

wherein:

X represents a hydrogen atom; a fluorine atom or a chlorine atom;

R represents a group having general formula (II) :

^R3 ^R5 - C I - C ≡ C - C I - OR- (II)

I \

^R. ^R6 or a group having general formula (III) :

I³

- C - CX. = CX-COOR- (III)

I R, R₁ and R-, the same or different, represent a hydrogen atom; or a C_j-C- alkyl or haloalkyl group, linear or branched;

R₃, R₄, R₅, R₆ and R-, the same or different, represent a hydrogen atom; or a C^C^ alkyl or haloalkyl group, linear or branched; X₁ and X-, the same or different, represent a hydrogen atom; a C,-C₄ alkyl or haloalkyl group, linear or branched; a C,-C₄ alkoxyl or haloalkoxyl group, linear or branched;

E represents one of the following heterocyclic groups represented by the following general formulae E₁ - E₁₀:

N

Eg

E lO wherein :

R_b represents a C.,-C₃ alkyl group, linear or branched;

R₈ and R₉, the same or different, represent a

C₁-C₄ alkyl or haloalkyl group, linear or branched;

R₁₀ and R_n, the same or different, represent a hydrogen atom; a C₁-C₆ alkyl group, linear or branched; a C₃-C₆ cycloalkyl group; a C₃-C₅ alkenyl group, linear or branched; a C₃-C₅ alkinyl group, linear or branched; or R₁₀ and

R jointly represent a C--C₅ alkylene or oxyalkylene chain, linear or branched; r represents 1 or 2 ; s represents an integer between 0 and 2 , extremes included.

The benzoxazinyl-heterocycles having general formula (I) have a high herbicidal activity.

A further object of the present invention relates to processes for the preparation of the compounds having general formula (I) . The compounds having general formula (I) , wherein E represents an E₁ group, corresponding to the following general formula (1-1) :

wherein X, R, R₁ , R₂, R_b, s and r have the same meanings described above, can be prepared by reacting an anhydride having general formula (IV) :

<

wherein R_b, s and r have the same meanings defined above, with a compound having general formula (V) :

wherein X, R, R₁ and R- have the same meanings described above .

The above reaction can be carried out without or in the presence of an inert organic solvent, at a temperature ranging from room temperature to the boiling point of the solvent possibly used, preferably between 60 °C and 200 °C, optionally in the presence of a catalyst.

Inert organic solvents which can be used for the purpose are, for example, benzene, toluene, xylene, chlorobenzene, acetic acid, diisopropylether, dimetho- xyethane, tetrahydrofuran, dioxane.

Catalysts which can be used for the purpose are, for example, mixtures of nitrogenated organic bases such as, for example, triethylamine, piperidine, pyrrolidine, with aliphatic carboxylic acids such as, for example, acetic acid, propionic acid, butyrric acid.

In order to facilitate the above reaction, it may also be useful to azeotropically remove the water which is formed during the condensation.

Anhydrides having general formula (IV) are compounds which are known in literature.

The aminobenzoxazinones having general formula (V) can be prepared according to the known methods. The compounds having general formula (I) , wherein E represents an E. group, corresponding to the following general formula (1-2):

wherein X, R, R₁ , R₂ and R₈ have the same meanings defined above, can be prepared by reacting with a cyclizing agent such as, for example, phosgene or trichloromethylchloroformiate, a hydrazide having general formula (VI) :

wherein X, R, R₁ , R₂ and R_g have the same meanings described above.

The above reaction can be carried out by treating the hydrazide having general formula (VI) , dissolved or suspended in a suitable inert organic solvent, with the cyclizing agent, optionally dissolved in turn in a suitable inert organic solvent, at a temperature ranging from 20 °C to the boiling point of the reaction mixture, possibly in the presence of an organic or inorganic base. Inert organic solvents which can be used for the purpose are, for example, methylene chloride, chloroform, 1, 2-dichloroethane, benzene, toluene, xylene, chlorobenzene, ethyl ether, tetrahydrofuran, dioxane, ethyl acetate.

Inorganic bases which can be used for the purpose are, for example, sodium bicarbonate, sodium carbonate, potassium carbonate.

Organic bases which can be used are, for example, triethyla ine, pyridine, 4-dimethylaminopyridine.

The hydrazides having general formula (VI) can be prepared by converting the a inobenzoxazinones having general formula (V) described above into the corresponding hydrazides having general formula (VII) :

wherein X, R, R₁ and R₂ have the same meanings defined above, and reacting the latter with acylic chlorides having general formula (VIII) :

R₈C0C1 (VIII) wherein R₈ has the same meanings described above, operating according to processes known in the art. The compounds having general formula (I) wherein E represents an E₃ group corresponding to the following general formula (1-3) , or an E₄ group corresponding to the following general formula (1-4), or an E₅ group corresponding to the following general formula (1-5) :

wherein X, R, R₁ , R₂, R_g, 1^, R_b, s and r have the same meanings described above, can be prepared by reacting the intermediates having general formula (IX-3), (IX-4) and (IX-5) , respectively:

wherein X, R, R₁ , R₂, R₈, R,, R_b, s and r have the same meanings described above, with a compound having general formula (X) :

R-X' (X) wherein R has the same meanings described above and X' represents a halogen atom, preferably chlorine or bromine, or an R'SO-0 group wherein R' represents a C₁-C₄ alkyl or haloalkyl group, linear or branched, or a phenyl group possibly substituted with C^-C_j alkyl groups, linear or branched, with nitro groups, or with halogen atoms such as bromine, chlorine and fluorine.

The above reaction can be advantageously carried out in an inert organic solvent and in the presence of an inorganic base, at a temperature ranging from -10 °C to the boiling point of the solvent used.

Inert organic solvents which can be used for the purpose are benzene, toluene, xylene, di ethoxyethane, diisopropylether, tetrahydrofuran, dioxane, acetoni- trile, N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, dimethylsulfoxide.

Inorganic bases which can be used for the purpose are, for example, hydroxides and carbonates of sodium, potassium and calcium, sodium hydride, sodium metho- xide.

The benzoxazinyl derivatives having general formulae (IX-3) , (IX-4) and (IX-5) and the compounds having general formula (X) can be prepared according to the methods known in literature.

The compounds having general formula (I) , wherein E represents an E₆ group, corresponding to the following general formula (1-6) :

wherein X, R, R₁ and R₂ have the same meanings described above, can be prepared by the cyclization, in the presence of a base, of a compound having general formula (XI)

wherein X, R, R₁ and R- have the same meanings defined above and R" represents a C₁-C₄ alkyl group, linear or branched.

The above reaction is preferably carried out in an inert organic solvent, in the presence of an organic or inorganic base, at a temperature ranging from room temperature to the boiling point of the reaction mixture.

Inert organic solvents which can be used for the purpose are, for example, benzene, toluene, xylene, dimethoxyethane, diisopropylether, tetrahydrofuran, dioxane, acetonitrile, N,N-dimethylformamide, N,N- dimethylacetamide, N-methylpyrrolidone, dimethylsulfoxide. Organic bases which can be used are, for example, triethylamine, pyridine, 4- (N,N-dimethylamine)pyridine, alkoxides of alkaline metals such as, for example, sodium ethoxide, sodium ethoxide, potassium t-butoxi- de, salts of carboxylic acids such as, for example, sodium acetate, potassium acetate.

Inorganic bases which can be used for the purpose are, for example, sodium hydride, potassium hydride, sodium carbonate, potassium carbonate, sodium hydoxide, potassium hydroxide. The intermediate having general formula (XI) can be prepared by the reaction of an arylisocyanate having general formula (XII) :

wherein X, R, R₁ and R- have the same meanings described above, with a compound having general formula (XIII) :

wherein R" has the same meaning described above.

The arylisocyanates having general formula (XII) can in turn be prepared by the reaction of an a inoben- zoxazinone having general formula (V) described above with phosgene or trichloromethylformiate, operating according to processes known in the art.

The compounds having general formula (XIII) are known in the art.

The compounds having general formula (I) , wherein

E represents an E- group, corresponding to the following general formula

wherein X, R, R₁ , R₂ and R₉ have the same meanings described above, can be prepared by the reaction of an arylisothiocyanate having general formula (XIV) :

wherein X, R, R₁ and R₂ have the same meanings described above, with a compound having general formula (XV) :

wherein R- has the same meanings described above, obtaining an intermediate having general formula (XVI) :

wherein X, R, R₁ , R₂ and R₉ have the same meanings described above, which is converted into the compounds having general formula (1-7) by oxidative cyclization. The reaction between the compounds having general formula (XIV) and (XV) is carried out in the presence of an inert organic solvent, at a temperature ranging from -50 °C to +50 °C, optionally in the presence of an organic or inorganic base.

Inert organic solvents which can be used for the purpose are, for example, ethyl ether, tetrahydrofuran, dioxane, methylene chloride, chloroform, ethyl acetate. Organic bases which can be used are, for example, triethylamine, pyridine, 4-dimethylaminopyridine.

Inorganic bases which can be used are, for example, sodium bicarbonate, sodium carbonate, potassium carbonate . The cyclization reaction of the intermediate having general formula (XVI) is carried out in the presence of an inert organic solvent, an oxidating agent and an acid acceptor, at a temperature ranging from -30°C to +30°C. Inert organic solvents which can be used for the purpose are, for example, methylene chloride, chloroform, chlorobenzene, N,N-dimethylformamide, ethyl acetate.

Oxidating agents which can be used are, for example, bromine, chlorine, sodium hypochlorite.

Acid acceptors which can be used for the purpose are, for example, organic bases such as, for example, triethylamine, pyridine, dimethylaniline, or inorganic bases such as, for example, sodium hydroxide, potassium carbonate, calcium carbonate. The arylisothiocyanates having general formula

(XIV) can in turn be prepared by the reaction of an aminobenzoxazinone having general formula (V) described above with phosgene or trichloromethylformiate, operat- ing according to processes known in the art.

The compounds having general formula (XV) are known in the art.

The compounds having general formula (I) , wherein E represents an E₈ group, corresponding to the following general formula (1-8) :

wherein X, R, R₁ , R₂, R_b, s and r, have the same meanings described above, can be prepared by the reaction with phosgene or trichloromethylchloroformiate of a compound having general formula (XVII) :

wherein X, R, R. , R₂, R_b, s and r, have the same mean- ings defined above. The reaction is carried out by treating the compound having general formula (XVII), dissolved or suspended in a suitable inert organic solvent, with phosgene or trichloromethylchloroformiate, possibly dissolved in turn in a suitable inert organic solvent, at a temperature ranging from 20 °C to the boiling point of the reaction mixture, optionally in the presence of an organic or inorganic base.

Inert organic solvents which can be used for the purpose are, for example, methylene chloride, chloroform, 1, 2-dichloroethane, benzene, toluene, xylene, chlorobenzene, ethyl ether, tetrahydrofuran, dioxane, ethyl acetate.

Organic bases which can be used are, for example, triethylamine, pyridine, 4-dimethylaminopyridine.

Inorganic bases which can be used are, for example, sodium bicarbonate, sodium carbonate, potassium carbonate.

The compounds having general formula (XVII) can in turn be prepared by the reaction of an arylisothiocya- nate having general formula (XIV) described above with a compound having general formula (XVIII) :

(XVIII)

wherein R_b, s and r have the same meanings described above, operating according to processes known in the art.

The compounds having general formula (I) , wherein E represents an E₉ group, corresponding to the following general formula (1-9) :

wherein X, R, R₁ , R₂, R_b, s and r, have the same meanings described above, can be prepared by the reaction with phosgene or trichloromethylchloroformiate of a compound having general formula (XIX) :

wherein X, R, R₁ , R₂, R_b, s and r, have the same mean- ings defined above.

The reaction is carried out by treating the compound having general formula (XIX) , dissolved or suspended in a suitable inert organic solvent, with phosgene or trichloromethylchloroformiate, possibly dissolved in turn in a suitable inert organic solvent, at a temperature ranging from 20 °C to the boiling point of the reaction mixture, optionally in the presence of an organic or inorganic base.

Inert organic solvents which can be used for the purpose are, for example, methylene chloride, chloroform, 1 , 2-dichloroethane, benzene, toluene, xylene, chlorobenzene, ethyl ether, tetrahydrofuran, dioxane, ethyl acetate.

The compounds having general formula (XIX) can in turn be prepared by the reaction of an arylisocyanate having general formula (XII) described above with a compound having general formula (XVIII) described above, operating according to processes known in the art. The compounds having general formula (I) , wherein E represents an E₁₀ group, corresponding to the following general

wherein X, R, R₁ , R_, R_b, R_1Q, R , s and r have the same meanings described above, can be prepared by the reaction of a compound having general formula (1-1) described above with an a ine having general formula (XX) :

/^Rιo HN (XX)

^R11 wherein R₁₀ and R_n have the same meanings described above.

The reaction is carried out in an inert organic solvent, at a temperature ranging from 0°C to the boiling point of the solvent used, possibly in the presence of an organic or inorganic base as catalyst. Inert organic solvents which can be used for the purpose are, for example, methylene chloride, chloroform, carbon tetrachloride, chlorobenzene, benzene, toluene, xylene, hexane, octane, cyclohexane, ethyl ether, tetrahydrofuran, di ethoxyethane, acetone, methylethylketone, acetonitrile, ethyl acetate, dimethylformamide .

Organic bases which can be used are, for example, triethylamine, pyridine.

Inorganic bases which can be used are, for exam- pie, sodium carbonate, potassium carbonate. Specific examples of benzoxazinyl-heterocycles having general formula (I) which are interesting for their herbicidal activity are indicated in Tables 1-10 below.

TABLE 1 Compounds having general formula (1-1) :

TABLE 2

Compounds having general formula (1-2)

TABLE 3

Compounds having general formula (1-3)

TABLE 4

Compounds having general formula (1-4) :

TABLE 5

Compounds having general formula (1-5)

TABLE 6

20 Compounds having general formula (1-6) :

TABLE 7

Compounds having general formula (1-7)

20 TABLE 8

Compounds having general formula (1-8)

TABLE 9 Compounds having general formula (1-9)

20 Compounds having general formula (1-10)

The compounds having general formula (I) of the present invention have shown a high herbicidal activity which makes them suitable for use in the agrarian field to defend crops from weeds.

In particular, the compounds having general formula (I) are effective in the control, both in pre- and post-emergency, of numerous monocotyledon and dicotyledon weeds. At the same time, these compounds have compatibility or no toxic effects with respect to useful crops, both in pre-emergency and post-emergency treatment.

Examples of weeds which can be efficiently controlled using the compounds having general formula (I) of the present invention are: Abutilon theofrasti, Amaranthus retroflexus, Capsella bursa pastoris, Chenopodium album, Convolvulus sepium, Galium aparine. Geranium dissecturo, Ipomea sp. , Matricaria chamomilla, Papaver rhoaes, Phaseolus aureus , Polvgonum persicaria, Portulaca oleracea, Sida spinosa, Solanum nicrrum, Stellaria media, Veronica persica, Xanthium sp. , etc.

With the doses used for agrarian applications, the above compounds have shown no toxic effects with respect to important crops such as rice (Oryza sativa) , wheat (Triticum spp. ) , maize (Zea mais) , soybean

(Glycine max) , etc.

A further object of the present invention relates to a method for controlling weeds in cultivated areas, by the application of the compounds having general formula (I) .

The quantity of compound to be applied to obtain the desired effect can vary in relation to different factors such as, for example, the compound used, the crop to be preserved, the weed to be fought against, the degree of infestation, the climatic conditions, the characteristics of the soil, the method of application, etc.

Doses of compound varying from 1 g to 1000 g per hectare generally give sufficient control.

For practical uses in agriculture, it is often advantageous to use compositions with a herbicidal activity containing, as active substance, one or more compounds having general formula (I) , possibly also as a mixture of isomers. Compositions can be used in the form of dry powders, wettable powders, emulsifiable concentrates, microemulsions , pastes, flakes, solutions, suspensions, etc.: the selection of the type of composition depends on the specific use.

The compositions are prepared according to the known methods, for example by diluting or dissolving the active substance with a solvent medium and/or solid diluent, optionally in the presence of surface-active agents.

Solid inert diluents, or carriers, which can be used are kaolin, alumina, silica, talc, bentonite, chalk, quartz, dolomite, attapulgite, mont orillonite, diatomaceous earth, cellulose, starch, etc. Liquid inert diluents, in addition to water of course, which can be used are organic solvents such as aromatic hydrocarbons (xylols, mixtures of alkylben- zols, etc.), aliphatic hydrocarbons (hexane, cyclohexa- ne, etc.), halogenated aromatic hydrocarbons (chloro- benzol, etc.), alcohols (methanol, propanol, butanol, octanol, etc.), esters (isobutyl acetate, etc.), ketones (acetone, cyclohexanone, acetophenone, isopho- rone, ethylamylketone, etc.), or vegetable or mineral oils or their mixtures, etc. Surface-active agents which can be used are wetting and emulsifying agents of the non-ionic type (polyethoxylated alkylphenols , polyethoxylated fatty alcohols, etc.), anionic type (alkylbenzenesulfonates , alkylsulfonates , etc.), cationic type (quaternary salts of alkylammonium, etc.).

It is also possible to use dispersing agents (for example lignin and its salts, derivatives of cellulose, alginates, etc.), stabilizers (for example antioxi- dants, ultraviolet ray absorbers, etc.). To widen the range of action of the above compositions, it is possible to add other active ingredients such as, for example, other herbicides, fungicides, insecticides or acaricides, fertilizers.

The concentration of active substance in the above compositions can vary within a wide range, depending on the active compound, the applications for which it is destined, the environmental conditions and the type of formulation adopted.

In general, the concentration of active substance is between 1% and 90%, preferably between 5% and 50%. The following examples are provided for illustrative purposes and do not limit the scope of the present invention. EXAMPLE 1 Preparation of N- [7-fluoro-3,4-dihydro- (4-methoxybut-2- inyl) -3-oxo-2H-l, 4-benzoxazin-6-yl] cyclo-hex-l-ene-1,2- dicarboxyimide (Compound Nr. 1) .

A mixture of 6-amino-7-fluoro-4- (4-methoxy-but-2- inyl) -2H-1, 4-benzoxazin-3 (4H) -one (0.9 g; 3.4 mmoles) , 3 , 4 , 5 , 6-tetrahydrophthalic anhydride (0.52 g; 3.4 mmoles) and acetic acid (15 ml), is heated to reflux temperature for 2 hours. After cooling it is diluted with water and the precipitate is filtered.

The solid obtained is then purified by silica gel chromatography eluating with hexane/ethyl acetate in a ratio fo 2:1.

0.9 g of the desired product having a melting point of 165°C-166°C, are obtained. EXAMPLE 2 Using the same procedure described in example 1, the following compounds were prepared starting from 3 , 4 , 5, 6-tetrahydrophthalic anhydride and the corresponding aminobenzoxazinones suitably substituted:

N- [7-fluoro-3 , 4-dihydro-4- (5-methoxypent-3-in-2- yl) -3-oxo-2H--l, 4--ben oxazin-6-yl ] cyclohex-1-- ene-1, 2-dicarboxyimide (Compound Nr. 2) ; N- [7-fluoro-3 , 4-dihydro—4— (4-methoxycarbonyl— (E) -but-3-en-2-yl) -3-oxo-benzoxazin—6—yl ] cyclo- hex-l-ene-1, 2-dicarboxyimide (Compound Nr. 3); - N- [7-fluoro-3 , 4-dihydro-4- (3-methoxycarbonyl-2- methoxy- (E) -prop-2-enyl) -3-oxo-2H-l , 4-benzoxazin— 6--yl ] cyclohex--l--ene-l , 2-dicarboxyimide (Compound Nr . 4 ) . EXAMPLE 3 Determinationn of the herbicidal activity in post- emergency.

The herbicidal activity of Compound Nr . 1 was evaluated in post-emergency treatment and was compared with the herbicidal activity of N- (7-fluoro-3 , 4-dihy- dro-3-oxo-4-prop-2-inyl-2H-l, 4—benzoxazin-6-yl) cyclo- hex-l-ene-1 , 2-dicarboxyimide (RC) corresponding to Compound Nr. 20 of U.S. patent 4.640.707.

The evaluation tests of each product were carried out according to the following operating procedures. Vases (diameter of more than 10 cm, height 10 cm) containing sandy earth were prepared. In each of these one of the following weeds was planted together with the following crops (10 vases for each species) : weeds (dicotyledons) : Abutilon theofrasti (AT) , Convolvulus sepium (CS) , Ipomea purpurea (IP) ; crops: Zea mays (maize) , Glycine max (soybean) . Water was added to each vase in a suitable quantity for a good germination of the seeds. The vases were divided into two groups each containing 5 vases for each weed or crop. Fifteen days after the planting, i.e. when the weeds, depending on the species, were 10-15 cm high, the first group of vases was treated with a hydroaceto- ne dispersion of the two products under examination (Compound Nr. 1 and Compound RC) , acetone at 10% by volume and Tween 20 at 0.5%.

The second group was only treated with a hydroace- tone solution containing acetone at 10% by volume and Tween 20 at 0.5%, and was used as a comparison (blank) . All the vases were kept under observation in a conditioned environment under the following environmental conditions: temperature: 24 °C; relative humidity: 60%; - photoperiod: 16 hours; luminous intensity: 10000 lux.

Every two days the vases were uniformly watered to ensure a sufficient degree of humidity for a good development of the plants. Fifteen days after the treatment, the herbicidal activity was evaluated, expressed according to a scale of values from 0 to 100, referring to the percentage of damage observed on the plants treated with respect to those not treated (blank) . According to this scale: - 0 = no herbicidal effect; 100 = death of the plant treated.

The results obtained are shown in Table 11 below.

TABLE 11 HERBICIAL ACTIVITY^(a IN POST-EMERGENCY AT DOSES OF 15- 50 g/ha.

(a) : each data is the average of at least 5 tests, (b) : the letters indicate the weeds listed above.

Claims

1. Benzoxazinyl-heterocycles having general formula

( I ) :

wherein :

X represents a hydrogen atom; a fluorine atom or a chlorine atom;

R represents a group having general formula (II) :

or a group having general formula (III) R,

- C - CX^ = CX-COOR- (III)

R. and R₂, the same or different, represent a hydrogen atom; or a C^C- alkyl or haloalkyl group, linear or branched;

R₃, R₄, R₅, R₆ and R_, the same or different, represent a hydrogen atom; or a C₁-C₄ alkyl or haloalkyl group, linear or branched;

X₁ and X₂, the same or different, represent a hydrogen atom; a C₁-C₄ alkyl or haloalkyl group, linear or branched; a C,-C₄ alkoxyl or haloalkoxyl group, linear or branched; E represents one of the following heterocyclic groups represented by the following general formulae E^E^:

Eg lO wherein:

R_b represents a ^- ₂ alkyl group, linear or branched;

R₈ and R-, the same or different, repre- sent a . -C_1t alkyl or haloalkyl group, linear or branched;

R₁₀ and R_n, the same or different, represent a hydrogen atom; a C₁-C₆ alkyl group, linear or branched; a C₃-C₆ cy- cloalkyl group; a C₃-C₅ alkenyl group, linear or branched; a C₃-C₅ alkinyl group, linear or branched; or R₁₀ and R_nι jointly represent a C₂-C₅ alkylene or oxyalkylene chain, linear or branched; - r represents 1 or 2 ; s represents an integer between 0 and 2 , extremes included. 2. Herbicides consisting of benzoxazinyl-heterocycles having general formula (I) :

wherein: - X represents a hydrogen atom; a fluorine atom or a chlorine atom;

R represents a group having general formula

(II):

or a group having general formula (III) :

R₃ C— <_X =CX₂COOR₇ ( II I ) ;

R

R₁ and R₂, the same or different, represent a hydrogen atom; or a C.,-C₃ alkyl or haloalkyl group, linear or branched; R₃, R₄, R₅, R₆ and R₇, the same or different, represent a hydrogen atom; or a C^C_^, alkyl or haloalkyl group, linear or branched; X₁ and X₂, the same or different, represent a hydrogen atom; a C₁-C₄ alkyl or haloalkyl group, linear or branched; a C₁-C₄ alkoxyl or haloalkoxyl group, linear or branched;

E represents one of the following heterocyclic groups represented by the following general formulae E.-E^:

Eg

20 ElO wherein:

R_b represents a Cy alkyl group, linear or branched;

R₈ and R-, the same or different, repre¬

25 sent a C₁-C₄ alkyl or haloalkyl group, linear or branched;

R₁₀ and R , the same or different, represent a hydrogen atom; a C₁-C₆ alkyl group, linear or branched; a C--C₆ cy- cloalkyl group; a C₅~C₅ alkenyl group, linear or branched; a C₃-C₅ alkinyl group, linear or branched; or R₁₀ and R jointly represent a C--C₅ alkylene or oxyalkylene chain, linear or branched; r represents 1 or 2 ; s represents an integer between 0 and 2 , extremes included.

3. A herbicide according to claim 2, consisting of N- [7-fluoro-3 , 4-dihydro- (4-methoxybut-2-inyl) -3-oxo- 2H-1, 4-benzoxazin-6-yl ] cyclo-hex-l-ene-1 , 2-dicar- boxyimide .

4. A herbicide according to claim 2, consisting of N- [7-fluoro-3 , 4-dihydro-4- (5-methoxypent-3-in-2-yl) - 3-oxo-2H-l,4-benzoxazin-6-yl] cyclohex-l-ene-1 , 2- dicarboxyimide.

5. A herbicide according to claim 2, consisting of N- [ 7-fluoro-3 , 4-dihydro-4- (4-methoxycarbonyl- (E) - but-3-en-2-yl) -3-oxo-benzoxazin—6-yl ] cyclohex-1- ene-1 , 2-dicarboxyimide. 6. A herbicide according to claim 2, consisting of N- [7-fluoro-3, 4-dihydro-4- (3-methoxycarbonyl-2- methoxy- (E) -prop-2-enyl) -3-oxo—2H—1, 4-benzoxa- zin-6-yl ] cyclohex-l-ene—1 , 2—dicarboxyimide . A process for the preparation of the benzoxazinyl- heterocycles having general formula (I) according to any of the previous claims, wherein E represents an E₁ group, corresponding to the following general formula (1-1) :

wherein X, R, R.,, R₂, R_b, s and r have the same meanings described above, which consists in the reaction of an anhydride having general formula

wherein X, R, R₁ and R- have the same meanings described above, said reaction being carried out without or in the presence of an inert organic solvent, at a temperature ranging from room temperature to the boiling point of the solvent possibly used, optionally in the presence of a catalyst. 8. The process for the preparation of the benzoxazinyl-heterocycles having general formula (I) according to any of the previous claims, wherein E represents an E₂ group, corresponding to the following general formula (1-2) :

wherein X, R, R₁ , R- and R₈ have the same meanings defined above, which consists in reacting a cyclizing agent such as phosgene or trichlorome- thylchloroformiate, with a hydrazide having general formula (VI) :

wherein X, R, R₁ , R. and R₈ have the same meanings described above, said reaction being carried out by treating the hydrazide having general formula (VI) , dissolved or suspended in a suitable inert organic solvent, with the cyclizing agent, optionally dissolved in turn in a suitable inert organic solvent, at .a temperature ranging from 20 °C to the boiling point of the reaction mixture, possibly in the presence of an organic or inorganic base. The process for the preparation of the benzoxazinyl-heterocycles having general formula (I) according to any of the previous claims, wherein E represents an E₃ group, corresponding to the following general formula (1-3) , or and E₄ group corresponding to the following general formula (I- 4), or an E₅ group corresponding to the following general formula (1-5) :

wherein X, R, R₁ , R₂, R_g, R,, R_b, s and r have the same meanings described above, which consists in the reaction of the intermediates having general formula (IX-3) , (IX-4) and (IX-5) , respectively:

(

wherein X, R, R₁ , R₂, R₈, R₉, R_b, s and r have the same meanings described above, with a compound having general formula (X) :

R-X' (X) wherein R has the same meanings described above and X' represents a halogen atom, or an R'SO-O group wherein R' represents a C₁-C₄ alkyl or haloalkyl group, linear or branched, or a phenyl group possibly substituted with 0,-C- alkyl groups, linear or branched, with nitro groups, or with halogen atoms such as bromine, chlorine and fluorine, said reaction being advantageously carried out in an inert organic solvent and in the presence of an inorganic base, at a temperature ranging from -10 °C to the boiling point of the solvent used.

10. The process for the preparation of the benzoxazinyl-heterocycles having general formula (I) according to any of the previous claims, wherein E represents an E₆ group, corresponding to the following general formula (1-6) :

wherein X, R, R₁ and R- have the same meanings described above, which consists in the cycliza- tion, in the presence of a base, of a compound having general formula (XI)

wherein X, -R, R__j and R₂ have the same meanings defined above and R" represents a C₁-C₄ alkyl group, linear or branched, said cyclization being carried out in the presence of an inert organic solvent and in the presence of an organic or inorganic base, at a temperature ranging from room temperature to the boiling point of the reaction mixture.

The process for the preparation of the benzoxazinyl-heterocycles having general formula (I) according to any of the previous claims, wherein E represents an E₇ group, corresponding to the following general formula (1-7) :

wherein X, R, R, , R₂ and R₉ have the same meanings described above, which consists in the reaction of an arylisothiocyanate having general formula (XIV) :

wherein R₉ has the same meanings described above, said reaction being carried out in the presence of an inert organic solvent, at a temperature ranging from -50°C to +50"C, possibly in the presence of an organic or inorganic base, obtaining an intermediate having general formula (XVI) :

wherein X, R, R₁ , R₂ and R, have the same meanings described above, which is converted into the compounds having general formula (1-7) by oxida- tive cyclization in the presence of an inert organic solvent, an oxidating agent and an acid acceptor, at a temperature ranging from -30 °C to +30°C.

The process for the preparation of the benzoxazinyl-heterocycles having general formula (I) according to any of the previous claims, wherein E represents an E₈ group, corresponding to the following general formula (1-8) :

wherein X, R, R.,, R₂, R_b, s and r, have the same meanings described above, which consists in the reaction with phosgene or trichloromethylchloroformiate of a compound having general formula (XVII) :

wherein X, R, R_1# R₂, R_b, s and r, have the same meanings defined above, wherein the compound having general formula (XVII) , dissolved or suspended in a suitable inert organic solvent, is treated with phosgene or trichloromethylchloro- formiate, possibly dissolved in turn in a suitable inert organic solvent, at a temperature ranging from 20°C to the boiling point of the reaction mixture, optionally in the presence of an organic or inorganic base. 13. The process for the preparation of the benzoxazinyl-heterocycles having general formula (I) according to any of the previous claims, wherein E represents an E₉ group, corresponding to the following general formula (1-9) :

wherein X, R, R₁ , R-, R_b, s and r, have the same meanings described above, which consists in the reaction with phosgene or trichloromethylchloroformiate of a compound having general formula (XIX) :

wherein X, R, R₁ , R₂, R_b, s and r, have the same meanings defined above, wherein the compound having general formula (XIX) , dissolved or suspended in a suitable inert organic solvent, is treated with phosgene or trichloromethylchloroformiate, possibly dissolved in turn in a suitable inert organic solvent, at a temperature ranging from 20°C to the boiling point of the reaction mixture, optionally in the presence of an organic or inorganic base.

The process for the preparation of the benzoxazinyl-heterocycles having general formula (I) according to any of the previous claims, wherein E represents an E₁₀ group, corresponding to the following general formula (1-10) :

wherein X, R, R,, R₂, R_b, R₁₀, R^, s and r have the same meanings described above, which consists in the reaction of a compound having general formula (1-1) described above with an amine having general formula (XX) :

/^R.0

HN (XX)

^K11 wherein R₁₀ and R have the same meanings described above, said reaction being carried out in an inert organic solvent, at a temperature ranging from 0°C to 100°C, possibly in the presence of an organic or inorganic base as catalyst.

15. Compositions with a herbicidal activity containing one or more benzoxazinyl-heterocycles according to any of the claims from 2 to 14, alone or in the presence of solid carriers, liquid diluents, surface-active agents or other active principles.

16. The herbicidal compositions according to claim 15, wherein the concentration of active substance is between 1% and 90%.

17. A method for the control of weeds in cultivated areas which consists in applying the compositions according to claims 15 and 16 to said areas.