WO1993004071A1

WO1993004071A1 - Benzothiazolone

Info

Publication number: WO1993004071A1
Application number: PCT/EP1992/001851
Authority: WO
Inventors: Georg Pissiotas; Hans Moser; Hans-Georg Brunner
Original assignee: Ciba Geigy AG
Current assignee: Novartis AG
Priority date: 1991-08-19
Filing date: 1992-08-13
Publication date: 1993-03-04
Anticipated expiration: 1994-02-19
Also published as: CA2076240A1; MX9204747A; IL102830A; CN1069977A; AU2113092A; EP0528765A1; SI9200182A; KR930004313A; CN1127255A; EP0528765B1; NO923232D0; FI923674A0; DE59208657D1; AU649867B2; IL102830A0; FI923674A7; NO923232L; NZ243978A; BR9203196A; TW211566B

Abstract

Benzothiazolone derivatives of formula (I), wherein Y is oxygen or sulfur; R1 is hydrogen or fluorine; and R2 is hydrogen, C1-C6alkyl, C2-C4alkenyl, or C2-C6alkynyl; halo-substituted C1-C6alkyl, C2-C4alkenyl, or C3-C6alkynyl; C1-C4alkoxy-C1-C4alkyl, C1-C4alkoxy-C1-C2alkoxy-C1-C2alkyl, 1-phenylpropen-3-yl, cyano- or C3-C6cycloalkyl-substituted C1-C6alkyl; carboxy-C1-C4alkyl, C1-C6alkoxycarbonyl-C1-C4alkyl, halo-C1-C6alkoxycarbonyl-C1-C4alkyl, C1-C4alkoxy-C1-C2alkoxycarbonyl-C1-C4alkyl, C1-C6alkoxycarbonyl-C1-C2alkoxycarbonyl-C1-C4alkyl, C3-C6cycloalkyl-C1-C2alkoxycarbonyl-C1-C4alkyl, C1-C5alkylaminocarbonyl-C1-C4alkyl, di-C1-C5alkylaminocarbonyl-C1-C4alkyl, C3-C6cycloalkyl, C1-C4alkylthio-C1-C4alkyl, benzyl, or halo-substituted benzyl, C1-C4alkylsulfonyl, C3-C6-alkenyloxy-C1-C4alkyl, C1-C8alkylcarbonyl, (a), (b), (c), C1-C4alkylthiocarbonyl-C1-C4alkyl, or the group (d); R3 is hydrogen or C1-C4alkyl; and R4 is hydrogen or C1-C4alkyl; have good pre- and post-emergence selective herbicidal properties.

Description

BENZOTHIAZOLONE

The present invention relates to novel herbicidally active benzothiazolone derivatives, to processes for the preparation thereof, to compositions comprising them as active ingredients and to the use thereof for controlling weeds, especially selectively in crops of useful plants.

Herbicidally active benzothiazolone derivatives are known, for example, from US Patent 4786310. Novel herbicidally active benzothiazolone derivatives have now been found.

The benzothiazolone derivatives according to the invention have the formula I

wherein

Y is oxygen or sulfur,

R₁ is hydrogen or fluorine; and

R₂ is hydrogen, C₁-C₆alkyl, C₂-C₄alkenyl, or C₂-C₆alkynyl; halo-substituted C₁ -C₆a lkyl,

C₂-C₄alkenyl, or C₃-C₆alkynyl; C₁-C₄alkoxy-C₁-C₄alkyl, C₁-C₄alkoxy-C₁-C₂alkoxy-

C₁-C₂alkyl, 1-phenylpropen-3-yl, cyano- or C₃-C₆cycloalkyl-substituted C₁-C₆alkyl; carboxy-C₁-C₄alkyl, C₁-C₆alkoxycarbonyl-C₁-C₄alkyl, halo-C₁-C₆alkoxycarbonyl-C₁-C₄- allcyl, C₁-C₄alkoxy-C₁-C₂alkoxycarbonyl-C₁-C₄alk yl, C₁-C₆alk oxycarbonyl-C₁-C₂alkoxy- carbonyl-C₁-C₄alkyl, C₃-C₆cycloalkyl-C₁-C₂alkoxycarbonyl-C₁-C₄alkyl, C₁-C₅alkyl- aminocarbonyl-C₁-C₄alkyl, di-C₁-C₅alkylaminocarbonyl-C₁-C₄alkyl, C₃-C₆cycloalkyl,

C₁-C₄alkylthio-C₁-C₄alkyl, benzyl or halo-substituted benzyl, C₁-C₄alkylsulfonyl, C₃-C₆- alkenyloxy-C₁-C₄alkyl, C₁-C₈alkylcarbonyl, C₁-C₄alkyl-COO

C₁-C₄alk ylthiocarbonyl-C₁-C₄alkyl, or

the group

C₁-C₄ alkyl - S - C - CH - O - C - C₁-C₄ alkyl ;

R₃ is hydrogen or C₁-C₄alkyl; and

R₄ is hydrogen or C₁-C₄alkyl.

The alkyl groups appearing in the definition of substituent R₂ may be straight-chain or branched and are, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, iso- butyl, tert-butyl, pentyl or the isomeric pentyls, hexyl or the isomeric hexyls.

Haloalkyl is, for example, fluoromethyl, difluoromethyl, trifluoromethyl, chloromethyl, dichloro methyl, trichloromethyl, 2,2,2-trifluoroe-hyl, 2-fluor oethyl, 2-chloroethyl, 2,2,2- trichloroethyl and 7-chloroheptyl; preferably trichloromethyl, difluorochloromethyl, trifluoromethyl and dichlorofluoromethyl.

Alkoxy is, for example, methoxy, ethoxy, propoxy, isopropoxy, n-butoxy, isobutoxy, secbutoxy and tert-butoxy; preferably methoxy and ethoxy.

In the above definitions, halogen is to be understood as being fluorine, chlorine, bromine and iodine, preferably fluorine, chlorine and bromine.

C₁-C₄alkylsulfon yl is, for example, methylsulfonyl, ethylsulfonyl, n-propylsulfonyl, isopropylsulfonyl, n-butylsulfonyl, sec-butylsulfonyl, isobutylsulfonyl and tert-butyl- sulfonyl.

The C₂-C₄alkenyl radicals may be in the Z-form (cis) or in the E-form (trans) and may be straight-chain or branched. Alkenyl radicals having a chain length of two or three carbon atoms are preferred. Examples of C₂-C₄ alkenyl radicals are: vinyl, allyl, methallyl, 1-methylvinyl and but-2-en-1-yl. Vinyl and allyl are preferred. In halo-substituted C₂-C₄- alkenyl radicals the individual meanings of halogen are fluorine, chlorine, bromine and iodine. Preferred halogen atoms that may occur as substituents of C₂-C₄alkenyl radicals are fluorine and chlorine. Preferred halo-substituted C₂-C₄alkenyl radicals are those having a chain length of two or three carbon atoms. Especially preferred C₂-C₄alkenyl radicals mono- to tri-substituted by halogen are 1-chlorovinyl, 2-chlorovinyl, 3-fluoroallyl and 4,4,4-trifluorobut-2-en-1-yl. 1-Chlorovinyl and 2-chlorovinyl are very especially preferred.

Alkylthio is, for example, methylthio, ethylthio, propylthio, isopropylthio, n-butylthio, isobutylthio, sec-butylthio and tert-butylthio, preferably methylthio and ethylthio.

The C₂-C₆alkynyl radicals may be straight-chain or branched. Alkynyl radicals having a chain length of 2 or 3 carbon atoms are preferred. C₂-C₆alkynyl radicals are, for example, ethynyl, propargyl, 1-propynyl, 3-butynyl, 1-methylpropargyl, 3-pentynyl and 3-hexynyl, with ethynyl and propargyl being especially preferred.

The C₃-C₆cycloalkyl groups appearing in the definition of substituent R₂ may be substituted or unsubstituted and include, for example, cyclopropyl, 2-fluorocyclopropyl, 2,4- difluorocyclopropyl, 2-chlorocyclopropyl, 2,3-dichlorocyclopropyl, 2-methylcyclopropyl, 2-methylthiocyclopropyl, 2,3-dimethylcyclopropyl, 2-methoxycyclopropyl, cyclobutyl, cyclopentyl, 3-methylcyclopentyl, 3,4-dimethoxycyclopentyl, cyclohexyl, 3-fluorocyclo- hexyl, 4-methylcyclohexyl and 4-methylthiocyclohexyl.

Of the compounds of formula I preference is given to those wherein R₁ is fluorine, with Y preferably being oxygen.

Special preference is given to those compounds of formula I wherein R₂ is hydrogen, C₁-C₄alkyl, C₂-C₄alkenyl, or C₂-C₄alkynyl; halo-substituted C₁-C₄alkyl, C₂-C₄alkenyl, or C₃-C₄alkynyl; C₁-C₄alkoxy-C₁-C₄alkyl, C₁-C₄alkoxy-C₁-C₂alkoxy-C₁-C₂alkyl, 1-phenyl- propen-3-yl, cyano- or C₃-C₆cycloalkyl-substituted C₁-C₄alkyl, benzyl or halo-substituted benzyl, C₃-C₆alkenyloxy-C₁-C₄alkyl, C₁-C₈alkylcarbonyl, C₁-C₄alkyl-COO-

C₁-C₄alkyl-COO C₁-C₄alkylthiocarbonyl-C₁-C₄alkyl, or

the group

C₁-C₄ alkyl-S-C-CH-O-C-C₁-C₄ alkyl ;

R₃ is hydrogen or C₁-C₄alkyl; and

R₄ is hydrogen or C₁-C₄alkyl.

Special interest is accorded also to compounds of formula I wherein R₂ is hydrogen, C₁-C₄alkyl, C₂-C₄alkenyl, or C₂-C₄alkynyl; halo-substituted C₁-C₄alkyl, C₂-C₄alkenyl, or C₃-C₄alkynyl; or C₁-C₂alkoxy-C₁-C₂alkyl.

Very special preference is given to those compounds of formula I wherein R₂ is hydrogen, C₁-C₄alkyl, C₂-C₄alkenyl, fluoro-substituted C₁-C₄alkyl or C₂-C₄alkenyl.

In a further prominent group of compounds of formula I, R₂ is C₃-C₆cycloalkyl, C₃-C₆- cycloalkyl-substituted C₁-C₆alkyl; C₁-C₄alkylthio-C₁-C₄alkyl, benzyl, or halo-substituted benzyl, C₁-C₄alkylsulfonyl, C₃-C₆alkenyloxy-C₁-C₄alkyl, C₁-C₄alkylcarbonyl, C₁-C₄alkyl-COO C₁-C₄ alkyl-COO-

alkylthiocarbonyl-C₁-C₄alkyl, or the group

C₁-C₄ alkyl-S-C-CH-O-C-C₁-C₄ alkyl

R₃ is hydrogen or C₁-C₄alkyl; and R₄ is hydrogen or C₁-C₄alkyl;

special prominence being given to those compounds wherein Y is oxygen, R₁ is fluorine and R₃ is hydrogen or methyl.

In a very especially preferred group of compounds of formula I, Y is oxygen, R₁ is fluorine and R₂ is C₁-C₃alkyl, CH₂F, CH₂CH₂F, CH₂CH₂CH₂F, CHF₂, allyl, propargyl, 1-methyl-3-propynyl, methoxycarbonylmethyl, ethoxycarbonylmethyl, isopropoxy- carbonylmethyl, 1-(methoxycarbonyl)-ethyl, 1-(ethoxycarbonyl)-ethyl or 1-(isopropoxy- carbonyl)-ethyl.

A preferred individual compound within the scope of formula I is:

9-[3-(1-methylethyl)-6-fluoro-2(3H)-benzothiazolon-5-yl]-8-thia-1,6-diazabicyclo[4.3.0]- nonan-7-one (Compound No. 1.001).

In a further, especially preferred sub-group of compounds of formula I,

R₂ is halo-substituted C₁-C₆alkyl, C₂-C₄alkenyl, or C₃-C₆alkynyl; C₁-C₄alkoxy-C₁-C₄- alkyl, C₁-C₄alkoxy-C₁-C₂alkoxy-C₁-C₂alkyl, cyano- or C₃-C₆cycloalkyl-suhstituted C₁-C₆alkyl; carboxy-C₁-C₄alkyl, C₁-C₆alkoxycarbonyl-C₁-C₄alkyl, C₁-C₄alkoxy-C₁-C₂- alkoxycarbonyl-C₁-C₄alk yl, C₁-C₆alkoxycarbonyl-C₁-C₂alkoxycarbonyl-C₁-C₄alkyl, C₃-C₆cycloalkyl-C₁-C ₂alkoxycarbonyl-C₁-C₄alkyl, C₁-C₅alkylammocarbonyl-C₁-C₄alkyl, di-C₁-C₅alkylaminocarbonyl-C₁-C₄alkyl, C₃-C₆cycloalkyl, C₁-C₄alkylthio-C₁-C₄alkyl,

C₃-C₆alkenyloxy-C₁-C₄alkyl, C₁-C₄alkyl-COO

C₁-C₄alkyl C₁-C₄alkylthiocarbonyl-C₁-C₄alkyl, or

the group

C₁-C₄ alkyl - S - C - CH - O - C - C₁-C₄ alkyl

R₁ preferably being fluorine and Y being oxygen. Of that group special preference is given to those compounds wherein

R₂ is C₁-C₄alkoxy-C₁-C₄alkyl, C₁-C₄alkoxy-C₁-C₂alkoxy-C₁-C₂alkyl, cyano-substituted C₁-C₆alkyl; carboxy-C₁-C₄alkyl, C₁-C₆alkoxycarbonyl-C₁-C₄alkyl, C₁-C₄alkoxy-C₁-C₂- alkoxycarbonyl-C₁-C₄alkyl, C₁-C₆alkoxycarbonyl-C₁-C₂alkoxycarbonyl-C₁-C₄alkyl, C₃-C₆cycloalkyl-C₁-C₂alkoxycarbonyl-C₁-C₄alkyl, C₁-C₅alkylaminocarbonyl-C₁-C₄alkyl, di-C₁-C₅alkylaminocarbonyl-C₁-C₄alkyl or C₃-C₆cycloalkyl, but more especially C₁-C₆- alkoxycarbonyl-C₁-C₄alkyl or C₁-C₄alkoxy-C₁-C₂alkoxycarbonyl-C₁-C₄alkyl.

The compounds of formula I are prepared by converting an isothiocyanate of formula ll

wherein the substituents R₁ and R₂ are as defined for formula I, with a hexahydro- pyridazine of formula llI

into a compound of formula IV

which is then reacted with a compound of formula V

CYCl₂ (V), wherein Y is oxygen or sulfur, in the presence of a base.

The reaction of the isothiocyanate of formula II with the hexahydropyridazine of formula HI is advantageously carried out in an inert solvent at temperatures of from -5°C up to the boiling temperature of the solvent, especially from 0 to +50°C, preferably at room temperature. Suitable solvents for this reaction are, for example, toluene, xylene, ethyl acetate and acetonitrile.

The reaction of the compound of formula IV with the compound of formula V is advantageously earned out in an inert solvent at low temperatures, preferably at from 0 to +50°C, especially at from 0 to +15°C. Suitable bases for this reaction are, for example, pyridine, triethylamine and N,N-dimethylaniline. Suitable solvents are, for example, 1,2-dichloro- ethane, die hloromethane and toluene.

The hexahydropyridazine of formula llI used as starting material for the compounds of formula I according to the invention is known from EP-A-0304920. The isothiocyanates of formula II and the preparation thereof are described in US Patent 4828 605.

The processes given above can be carried out analogously to processes known in the literature. The reaction conditions preferred in those processes, such as temperature, molar ratios of the starting materials, reaction procedure, solvent, any reagents which may be necessary, such as acids, bases, water-binding agents etc., are familiar to the person skilled in the art.

The compounds of formula I are used in unmodified form, as obtainable from the synthesis, or, preferably, together with the adjuvants customarily employed in formulation technology and are therefore formulated in known manner e.g. into emulsifiable concentrates, directly sprayable or dilutable solutions, dilute emulsions, wettable powders, soluble powders, dusts, granules, and also encapsulations in e.g. polymer substances. As with the nature of the compositions, the methods of application, such as spraying, atomising, dusting, wetting, scattering or pouring, are chosen in accordance with the intended objectives and the prevailing circumstances.

The formulations, i.e. the compositions, preparations or mixtures comprising the compound (active ingredient) of formula I and, where appropriate, one or more solid or liquid adjuvants, are prepared in known manner, e.g. by homogeneously mixing and/or grinding the active ingredients with extenders, e.g. solvents, solid carriers and, where appropriate, surface-active compounds (surfactants).

Suitable solvents are: aromatic hydrocarbons, preferably the fractions containing 8 to 12 carbon atoms, such as mixtures of alkylbenzenes, e.g. xylene mixtures or alkylated naphthalenes; aliphatic and cycloaliphatic hydrocarbons, such as paraffins, cyclohexane or tetrahydronaphthalene; alcohols, such as ethanol, propanol or butanol; glycols and their ethers and esters, such as propylene glycol or dipropylene glycol ether, ketones, such as cyclohexanone, isophorone or diacetone alcohol; strongly polar solvents, such as N- methyl-2-pyrrolid one, dimethyl sulfoxide or water; vegetable oils and esters thereof, such as rape oil, castor oil or soybean oil; and, where appropriate, also silicone oils.

The solid carriers used, e.g. for dusts and dispersible powders, are normally natural mineral fillers, such as calcite, talcum, kaolin, montmorillonite or attapulgite. In order to improve the physical properties it is also possible to add highly dispersed silicic acid or highly dispersed absorbent polymers. Suitable granulated adsorptive carriers are porous types, for example pumice, broken brick, sepiolite or bentonite; and suitable nonsorbent carriers are, for example, calcite or sand. In addition, a great number of pregranulated materials of inorganic or organic nature can be used, e.g. especially dolomite or pulverised plant residues.

Depending upon the nature of the compound of formula I to be formulated, suitable surface-active compounds are non-ionic, cationic and/or anionic surfactants having good emulsifying, dispersing and wetting properties. The term "surfactants" will also be understood as comprising mixtures of surfactants.

Both so-called water-soluble soaps and water-soluble synthetic surface-active compounds are suitable anionic surfactants.

Suitable soaps are the alkali metal salts, alkaline earth metal salts or unsubstituted or substituted ammonium salts of higher fatty acids (C₁₀-C₂₂), e.g. the sodium or potassium salts of oleic or stearic acid, or of natural fatty acid mixtures which can be obtained e.g. from coconut oil or tallow oil. Mention may also be made of fatty acid methyltaurin salts.

More frequently, however, so-called synthetic surfactants are used, especially fatty alcohol sulfonates, fatty alcohol sulfates, sulfonated benzimidazole derivatives or alkylaryl sulfonates.

The fatty alcohol sulfonates or sulfates are usually in the form of alkali metal salts, alkaline earth metal salts or unsubstituted or substituted ammonium salts and contain a C₈-C₂₂alkyl radical, which also includes the alkyl moiety of acyl radicals, e.g. the sodium or calcium salt of lignosulfonic acid, of dodecyl sulfate or of a mixture of fatty alcohol sulfates obtained from natural fatty acids. These compounds also comprise the salts of sulfated and sulfonated fatty alcohol/ethylene oxide adducts. The sulfonated benzimidazole derivatives preferably contain two sulfonic acid groups and one fatty acid radical containing 8 to 22 carbon atoms. Examples of alkylarylsulfonates are the sodium, calcium or triethanolamine salts of dodecylbenzenesulfo nic acid, dibutylnaphthalene- sulfonic acid, or of a condensate of naphthalenesulfonic acid and formaldehyde.

Also suitable are corresponding phosphates, e.g. salts of the phosphoric acid ester of an adduct of p-nonylphenol with 4 to 14 mol of ethylene oxide, or phospholipids.

Non-ionic surfactants are preferably polyglycol ether derivatives of aliphatic or cycloaliphatic alcohols, saturated or unsaturated fatty acids and alkylphenols, said derivatives containing 3 to 30 glycol ether groups and 8 to 20 carbon atoms in the (aliphatic) hydrocarbon moiety and 6 to 18 carbon atoms in the alkyl moiety of the alkylphenols.

Further suitable non-ionic surfactants are the water-soluble adducts of polyethylene oxide with polypropylene glycol, ethylenediaminopolypropylene glycol and alkylpolypropylene glycol containing 1 to 10 carbon atoms in the alkyl chain, which adducts contain 20 to 250 ethylene glycol ether groups and 10 to 100 propylene glycol ether groups. These compounds usually contain 1 to 5 ethylene glycol units per propylene glycol unit.

Representative examples of non-ionic surfactants are nonylphenol polyethoxyethanols, castor oil polyglycol ethers, polypropylene/polyethylene oxide adducts, tributylphenoxy- polyethoxyethanol, polyethylene glycol and octylphenoxypolyethoxyethanol.

Fatty acid esters of polyoxyethylene sorbitan, e.g. polyoxyethylene sorbitan trioleate, are also suitable non-ionic surfactants.

Cationic surfactants are preferably quaternary ammonium salts which contain, as

N-substituent, at least one C₈-C₂₂alkyl radical and, as further substituents, unsubstituted or halogenated lower alkyl, benzyl or hydroxy-lower alkyl radicals. The salts are preferably in the form of halides, methyl sulfates or ethyl sulfates, e.g. stearyltrimethylammonium chloride or benzyldi(2-chloroethyl)ethylammonium bromide.

The surfactants customarily employed in formulation technology arc described inter alia in the following publications:

- "Mc Cutcheon's Detergents and Emuls ers Annual", MC Publishing Corp.,

Glen Rock, New Jersey, 1988.

- M. and J. Ash, "Encyclopedia of Surfactants", Vol. I-llI, Chemical Publishing Co., New York, 1980-1981.

- Dr. Helmut Stache "Tensid-Taschenbuch" (Surfactant Handbook), Carl Hanser Verlag, Munich/Vienna 1981.

The pesticidal compositions usually comprise 0.1 to 99 %, preferably 0.1 to 95 %, of a compound of formula l, 1 to 99 % of a solid or liquid adjuvant, and 0 to 25 %, preferably 0.1 to 25 %, of a surfactant

Whereas commercial products will preferably be formulated as concentrates, the end user will normally employ dilute formulations.

The compositions may also comprise further auxiliaries, such as stabilisers, e.g. vegetable oils or epoxidised vegetable oils (epoxidised coconut oil, rape oil or soybean oil), anti- foams, e.g. silic one oil, preservatives, viscosity regulators, binders and tackifiers, as well as fertilisers or other active ingredients for obtaining special effects.

Preferred formulations have especially the following composition (throughout,

percentages are by weight)

Emulsifiable concentrates:

active ingredient: 1 to 90 %, preferably 5 to 20 %

surface-active agent: 1 to 30 %, preferably 10 to 20 %

liquid carrier: 5 to 94 %, preferably 70 to 85 %

Dusts:

active ingredient: 0.1 to 10 %, preferably 0.1 to 1 % solid carrier: 99.9 to 90 %, preferably 99.9 to 99 %

Suspension concentrates:

active ingredient: 5 to 75 %, preferably 10 to 50 %

water 94 to 24 %, preferably 88 to 30 %

surface-active agent: 1 to 40 %, preferably 2 to 30 %

Wettable powders:

active ingredient: 0.5 to 90 % , preferably 1 to 80 %

surface-active agent: 0.5 to 20 %, preferably 1 to 15 %

solid carrier: 5 to 95 %, preferably 15 to 90 %

Granules:

active ingredient: 0.5 to 30 %, preferably 3 to 15 %

solid carrier: 99.5 to 70 %, preferably 97 to 85 %

The compounds of formula I are generally used successfully at rates of application of from 0.001 to 4 kg/ha, especially from 0.005 to 1 kg/ha. The concentration required to achieve the desired effect can be determined by experiment It is dependent upon the type of action, the stage of development of the cultivated plant and of the weed, and also upon the application (place, time, method) and, in dependence on those parameters, can vary within wide limits.

When used at relatively low rates of application, the compounds of formula I are distinguished by growth-inhibiting and herbicidal properties, which render them excellently suitable for use in crops of useful plants, especially in cereals, cotton, soybeans, rape, maize and rice.

The invention relates also to herbicidal compositions comprising a novel compound of formula I, and to methods of inhibiting plant growth. Preparation Examples:

Example P1: Preparation of 2-[6-fluoro-3-(1-methylethyl)-2-benzothiazolon-5-yl-amino- thiocarbonyl] -hexahydropyridazine :

At a temperature of +5°C, a solution of 10.8 g of 6-fluoro-3-(1-methylethyl)-2-benzo- thiazolon-5-yl-isothiocyanate in 150 ml of ethanol is added dropwise to a solution of 3.6 ml of hexahydropyridazine in 50 ml of ethanol. After being stirred for 12 hours at room temperature, the reaction mixture is concentrated by evaporation. Purification by means of silica gel chromatography (ethyl acetate/n-hexane 1:9) yields 6.9 g of 2-[6- fluoro-3-(1-methylethyl)-2-benzothiazolon-5-yl-aminothioc arbonyl]-hexahydropyridazine having a melting point of 198-199°C.

Example P2: Preparation of 9-[3-(1-methylethyl)-6-fluoro-2(3H)-benzothiazolon-5-yl]-8- thia-1,6-diazabicyclo[4.3.0]nonan-7-one (Compound No. 1.001):

At a temperature of +5°C, 7 ml of a 20 % toluene solution of phosgene is added dropwise to a solution of 4.4 g of 2-[6-fluoro-3-(1-memylethyl)-2-benzo thiazolon-5-yl-aminothio- carbonyl]-hexahydropyridazine prepared according to Example P1. After being stirred for one hour, the reaction mixture is poured into ice-water. After separation of the organic phase and drying over sodium sulfate, the solution is concentrated by evaporation.

Chromatographic purification over silica gel (ethyl acetate/n-hexane 1:1) yields 2.9 g of 9-[3-(1-methylethyl)-6-fluoro-2(3H)-benzothiazolon-5-yl]-8-thia-1,6-diazabicyclo[4.3.0]- nonan-7-one (Compound No. 1.001) having a melting point of 132-133°C.

The compounds of Table 1 can be prepared analogously to the above Example and the preparation processes mentioned in the description:

₁ H H H

6₁

₁

₁

C

1

₁

_D ¹⁹

D¹⁹

₁

₁

O

₁

₁

₁

O

₁

₁

₁ .

.

₁

₁

₁

₁

₁

253

.

₁

₁ .

.

₁ . .

.

₁ .

.

₁

₁

₁

₁

₁

₁

₁

₁

₁

O

Formulation Examples for liquid active ingredients of formula I (throughout percentages are by weight)

1. Emulsifiable concentrates a) b) c)

a compound of Table 1 25% 40% 50%

calcium dodecylbenzenesulfonate 5% 8% 6%

castor oil polyethylene glycol

ether (36 mol of ethylene oxide) 5% - - tributylphenol polyethylene glycol

ether (30 mol of ethylene oxide) - 12% 4%

cyclohexanone - 15% 20%

xylene mixture 65% 25% 20%

Emulsions of any desired concentration can be produced from such concentrates by dilution with water.

2. Solutions a) b) c) d) a compound of Table 1 80% 10% 5% 95% propylene glycol monomethyl ether 20% - - - polyethylene glycol

(mol. wt 410) - 70% - -

N-methyl-2-pyrrolidone - 20% - - epoxidised coconut oil - - 1% 5% benzine (boiling range 160-190°C) - - 94% -

The solutions are suitable for application in the form of micro-drops.

3. Granules a) b) c) d) a compound of Table 1 5% 10% 8% 21% kaolin 94% - 79% 54% highly dispersed silicic acid 1% - 13% 7% attapulgite - 90% - 18%

The active ingredient is dissolved in methylene chloride, the solution is sprayed onto the carrier, and the solvent is subsequently evaporated off in vacuo. 4. Dusts a) b)

a compound of Table 1 2 % 5 %

highly dispersed silicic acid 1 % 5 %

talcum 97 % _

kaolin - 90 %

Ready-for-use dusts are obtained by intimately mixing the carriers with the active ingredient.

Formulation Examples for solid active ingredients of formula I (throughout, percentages are by weight)

5. Wettable powders a) b) c)

a compound of Table 1 25 % 50 % 75 %

sodium lignosulfonate 5 % 5 % - sodium laurylsulfate 3 % - 5 %

sodium dϋsobutylnaphthalene- sulfonate - 6 % 10 %

octylphenol polyethylene glycol

ether (7-8 mol of ethylene oxide) - 2 % - highly dispersed silicic acid 5 % 10 % 10 %

kaolin 62 % 27 % _

The active ingredient is thoroughly mixed with the adjuvants and the mixture is thoroughly ground in a suitable mill, affording wettable powders which can be diluted with water to give suspensions of the desired concentration.

6. Emulsifiable concentrate

a compound of Table 1 10 %

octylphenol polyethylene glycol ether

(4-5 mol of ethylene oxide) 3 %

calcium dodecylbenzenesulfonate 3 %

castor oil polyglycol ether

(36 mol of ethylene oxide) 4 %

cyclohexanone 30 %

xylene mixture 50 % Emulsions of any required concentration can be obtained from this concentrate by dilution with water.

7. Dusts a) b)

a compound of Table 1 5 % 8 %

talcum 95 % - kaolin - 92 %

Ready-for-use dusts are obtained by mixing the active ingredient with the carrier and grinding the mixture in a suitable mill.

8. Extruder granules

a compound of Table 1 10 %

sodium lignosulfonate 2 %

carboxymethylcellulose 1 %

kaolin 87 %

The active ingredient is mixed and ground with the adjuvants, and the mixture is moistened with water. The mixture is extruded and then dried in a stream of air.

9. Coated granules

a compound of Table 1 3 %

polyethylene glycol (mol. wt. 200) 3 %

kaolin 94 %

The finely ground active ingredient is uniformly applied, in a mixer, to the kaolin moistened with polyethylene glycol. Non-dusty coated granules are obtained in this manner.

10. Suspension concentrate

a compound of Table 1 40 %

propylene glycol 10 %

nonylphenol polyethylene glycol ether

( 15 mol of ethylene oxide) 6 %

sodium lignosulfonate 10 % carboxymethylcellulose 1 %

silicone oil in the form of a 75%

aqueous emulsion 1 %

water 32 %

The finely ground active ingredient is intimately mixed with the adjuvants, giving a suspension concentrate from which suspensions of any desired concentration can be obtained by dilution with water.

The compounds of formula I are used in unmodified form or, preferably, in the form of compositions together with the adjuvants customarily employed in formulation technology and are therefore formulated in known manner e.g. into emulsifiable concentrates, directly sprayable or dilutable solutions, dilute emulsions, wettable powders, soluble powders, dusts, granules, and also encapsulations in e.g. polymer substances. As with the nature of the compositions, the methods of application, such as spraying, atomising, dusting, scattering or pouring, are chosen in accordance with the intended objectives and the prevailing circumstances.

Biological Examples:

Example B1: Pre-emergence herbicidal action

In a greenhouse, immediately after the test plants have been sown in seed trays, the surface of the soil is treated with an aqueous spray mixture corresponding to a rate of application of 4 kg of active ingredient/hectare. The seed trays are kept in the greenhouse at 22 - 25°C and 50 - 70 % relative humidity.

The herbicidal action is evaluated after 3 weeks using a scale of nine ratings (1 = total damage, 9 = no damage) in comparison with an untreated control group.

Ratings from 1 to 4 (especially from 1 to 3) indicate a good to very good herbicidal action. Ratings from 6 to 9 (especially from 7 to 9) indicate good tolerance (especially in cultivated plants).

In this test, the compounds of Table 1 exhibit pronounced herbicidal activity. For example, compound 1.001 exhibits the following herbicidal action against the tested weeds:

Table B1: Pre-emergence herbicidal action:

Example B2: Pre-emergence herbicidal action

In a greenhouse, immediately after the test plants have been sown in seed trays, the surface of the soil is treated with an aqueous spray mixture corresponding to a rate of application of 2 kg of active ingredient/hectare. The seed trays are kept in the greenhouse at 22 - 25°C and 50 - 70 % relative humidity.

In this test, the compounds of Table 1 exhibit pronounced herbicidal activity. Examples of good herbicidal activity are given in Table B2:

Example B3: Post-emergence herbicidal action (contact herbicide)

A number of weeds, both monocotyledonous and dicotyledonous, are sprayed post- emergence (in the 4- to 6-leaf stage) with an aqueous active ingredient dispersion at a rate of 4 kg of active ingredient/hectare and kept at 24°-26°C and 45-60 % relative humidity. The herbicidal action is evaluated 15 days after treatment using a scale of nine ratings (1 = total damage, 9 = no damage) in comparison with an untreated control group.

Example B4: Post-emergence herbicidal action (contact herbicide)

A number of weeds, both monocotyledonous and dicotyledonous, are sprayed post- emergence (in the 4- to 6-leaf stage) with an aqueous active ingredient dispersion at a rate of 2 kg of active ingredient/hectare and kept at 24°-26°C and 45-60 % relative humidity. The herbicidal action is evaluated 15 days after treatment using a scale of nine ratings (1 = total damage, 9 = no damage) in comparison with an untreated control group.

In this test, the compounds of Table 1 exhibit pronounced herbicidal activity. Examples of good herbicidal activity are given in Table B4:

Example B5: Herbicidal action in wild rice (paddy)

The weeds Echinochloa crus galli and Monocharia vag., which occur in water, are sown in plastic beakers (surface area: 60 cm², volume: 500 ml). After sowing, the beakers are filled with water up to the surface of the soil. 3 days after sowing, the water level is increased to slightly above the soil surface (3-5 mm). Application is effected 3 days after sowing by spraying the beakers with the test compounds. The dosage corresponds to an amount of active ingredient of 4 kg a.i. per hectare. The beakers are then kept in a greenhouse under optimum growth conditions for rice weeds, i.e.25°-30°C and high humidity.

The tests are evaluated 3 weeks after application. The compounds of Table 1 damage the weeds.

Claims

What is claimed is:

1. A benzothiazolone derivative of formula I

wherein

Y is oxygen or sulfur,

R₁ is hydrogen or fluorine; and

R₂ is hydrogen, C₁-C₆alkyl, C₂-C₄alkenyl, or C₂-C₆alkynyl; halo-substituted C₁-C₆alkyl,

C₁-C₂alkyl, 1-phenylpropen-3-yl, cyano- or C₃-C₆cycloalkyl-substituted C₁-C₆alkyl; carboxy-C₁-C₄alkyl, C₁-C₆alkoxycarbonyl-C₁-C₄alkyl, halo-C₁-C₆alkoxycarbonyl-C₁-C₄- alkyl, C₁-C₄alkoxy- C₁-C₂alkoxycarbonyl-C₁-C₄alkyl, C₁-C₆alkoxycarbonyl-C₁-C₂alkoxy- carbonyl-C₁-C₄alkyl, C₃-C₆cycloalkyl-C₁-C₂alkoxycarbonyl-C₁-C₄alkyl, C₁-C₅alkyl- aminocarbonyl-C₁-C₄alkyl, di-C₁-C₅alkylaminocarbonyl-C₁-C₄alkyl, C₃-C₆cycloalkyl,

C₁-C₄alkylthio-C₁-C₄alkyl, benzyl, or halo-substituted benzyl, C₁-C₄alkylsulfonyl, C₃-C₆- alkenyloxy-C₁-C₄alkyl, C₁-C₈alkylcarbonyl, C₁-C₄alkyl-COO

C₁-C₄alkyl-COO- C₁-C₄alkylthiocarbonyl-C₁-C₄alkyl, or

the group

C₁-C₄ alkyl- S - C - CH - O - C - C₁ - C₄ alkyl ;

R₃ is hydrogen or C₁-C₄alkyl; and

R₄ is hydrogen or C₁-C₄alkyl.

2. A compound according to claim 1 wherein R₁ is fluorine.

3. A compound according to claim 1 wherein R₁ is fluorine and Y is oxygen.

4. A compound according to claim 1 wherein R₂ is hydrogen, C₁-C₄alkyl, C₂-C₄alkenyl, or C₂-C₄alkynyl; halo-substituted C₁-C₄alkyl, C₂-C₄alkenyl, or C₃-C₄alkynyl; C₁-C₄- alkoxy-C₁-C₄alkyl, C₁-C₄alkoxy-C₁-C₂alkoxy-C₁-C₂alkyl, 1-phenylpropen-3-yl, cyano- or C₃-C₆cycloalkyl-substituted C₁-C₄alkyl, benzyl, or halo-substituted benzyl, C₃-C₆alkenyl- oxy-C₁-C₄alkyl, C₁-C₈alkylcarbonyl, C₁-C₄alkyl-COO

C₁-C₄alkyl-CO O C₁-C₄alkylthiocarbonyl-C₁-C₄alkyl, or

the group

C₁-C₄ alkyl - S - C - CH - O - C - C₁-C₄ alkyl ;

R₃ is hydrogen or C₁-C₄alkyl; and

R₄ is hydrogen or C₁-C₄alkyl.

5. A compound according to claim 1 wherein R₂ is hydrogen, C₁-C₄alkyl, C₂-C₄alkenyl, or C₂-C₄alkynyl; halo-substituted C₁-C₄alkyl, C₂-C₄alkenyl, or C₃-C₄alkynyl; or C₁-C₂- alkoxy- C₁-C₂alkyl.

6. A compound according to claim 1 wherein R₂ is hydrogen, C₁-C₄alkyl, C₂-C₄alkenyl, fluoro-substituted C₁-C₄alkyl or C₂-C₄alkenyl.

7. A compound according to claim 1 wherein R₂ is C₃-C₆cycloalkyl, C₃-C₆cycloalkyl- substituted C₁-C₆alkyl; C₁-C₄alkylthio-C₁-C₄alkyl, benzyl, or halo-substituted benzyl, C₁-C₄alkylsulfonyl, C₃-C₆alkenyloxy-C₁-C₄alkyl, C₁-C₈alkylcarbonyl,

alkylthiocarbonyl-C₁-C₄alkyl, or the group

C₁-C₄ alkyl - S - C - CH - O - C - C₁-C₄ alkyl ;

R₃ is hydrogen or C₁-C₄alkyl; and

R₄ is hydrogen or C₁-C₄alkyl.

8. A compound according to claim 7 wherein Y is oxygen, R₁ is fluorine and R₃ is hydrogen or methyl.

9. A compound according to claim 1 wherein Y is oxygen, R₁ is fluorine and R₂ is C₁-C₃- alkyl, CH₂F, CH₂CH₂F, CH₂CH₂CH₂F, CHF₂, allyl, propargyl, 1-methyl-3-propynyl, methoxycarbonylmethyl, ethoxycarbonylmethyl, isopropoxycarbonylmethyl, 1-(methoxy- carbonyl)-ethyl, 1-(ethoxycarbonyl)-ethyl or 1-(isopropoxycarbonyl)-ethyl.

10. 9-[3-(1-methylethyl)-6-fluoro-2(3H)-benzothiazolon-5-yl]-8-thia-1,6-diazabicyclo- [4.3.0]nonan-7-one according to claim 1.

11. A compound according to claim 1 wherein R₂ is halo-substituted C₁-C₆alkyl, C₂-C₄- alkenyl, or C₃-C₆alkynyl; C₁-C₄alkoxy-C₁-C₄alkyl, C₁-C₄alkoxy-C₁-C₂alkoxy-C₁-C₂- alkyl, cyano- or C₃-C₆cycloalkyl-substituted C₁-C₆alkyl; carboxy-C₁-C₄alkyl, C₁-C₆- alkoxycarbonyl-C₁-C₄alkyl, C₁-C₄ alkoxy- C₁-C₂alkoxycarbonyl- C₁-C₄alkyl, C₁-C₆alkoxy- carbonyl-C₁-C₂alkoxycarbonyl-C₁-C₄alkyl, C₃-C₆cycloalkyl-C₁-C₂alkoxycarbonyl-C₁-C₄- alkyl, C₁-C₅alkylaminocarbonyl-C₁-C₄alkyl, di-C₁-C₅alkylaminocarbonyl-C₁-C₄alkyl, C₃-C₆cycloalkyl, C₁-C₄alkylthio-C₁-C₄alkyl, C₃-C₆alkenyloxy-C₁-C₄alkyl, C₁-C₄alkyl-COO-

alkylthiocarbonyl-C₁-C₄alkyl, or the group

C₁-C₄ alkyl - S - C - CH - O - C - C₁-C₄ alkyl

12. A compound according to claim 11 wherein R₂ is C₁ -C₄alkoxy-C₁-C₄alkyl, C₁-C₄- alkoxy- C₁-C₂alkoxy- C₁-C₂a lkyl, cyano-substituted C₁-C₆alkyl; carboxy-C₁-C₄alkyl, C₁-C₆alkoxycarbonyl-C₁-C₄alkyl, C₁-C₄alkoxy-C₁-C₂alkoxycarbonyl-C₁-C₄alkyl, C₁-C₆- alkoxycarbonyl-C₁-C₂alkoxycarbonyl-C₁-C₄alkyl, C₃-C₆cycloalkyl-C₁-C₂alkoxy- carbonyl-C₁-C₄alkyl, C₁-C₅alkylaminocarbonyl-C₁-C₄alkyl, di-C₁-C₅alkylamino- carbonyl-C₁-C₄alkyl or C₃-C₆cycloalkyl.

13. A compound according to claim 12 wherein R₂ is C₁-C₆alkoxycarbonyl-C₁-C₄alkyl or C₁-C₄alkoxy-C₁-C₂alkoxycarbonyl-C₁-C₄alkyl.

14. A compound according to claim 11 wherein R₁ is fluorine and Y is oxygen.

15. A process for the preparation of a compound of formula I

wherein

Y is oxygen or sulfur,

R₁ is hydrogen or fluorine; and

C₂-C₄alkenyl, or C₃-C₆alkynyl; C₁-C₄alkoxy-C₁-C₄alkyl, C₁-C₄alkoxy-C₁-C₂alkoxy- C₁-C₂alkyl, 1-phenylpropen-3-yl, cyano- or C₃-C₆cycloalkyl-substituted C₁-C₆alkyl; carboxy-C₁-C₄alkyl, C₁-C₆alkoxycarbonyl-C₁-C₄alkyl, halo-C₁-C₆alkoxycarbonyl-C₁-C₄ - alkyl, C₁-C₄alkoxy- C₁-C₂alkoxycarbonyl- C₁-C₄alkyl, C₁-C₆alkoxycarbonyl-C₁-C₂alkoxy- carbonyl-C₁-C₄alkyl, C₃-C₆cycloalkyl-C₁-C₂alkoxycarbonyl-C₁-C₄alkyl, C₁-C₅alkyl- aminocarbonyl-C₁-C₄alkyl, di-C₁-C₅alkylaminocarbonyl- C₁-C₄alkyl, C₃-C₆cycloalkyl, C₁-C₄alkylthio-C₁-C₄alkyl, benzyl, or halo-substituted benzyl, C₁-C₄alkylsulfonyl, C₃-C₆- alkenyloxy-C₁-C₄alkyl, C₁-C₈alkylcarbonyl, C₁-C₄alkyl-CO

C₁-C₄alkyl-COO C₁-C₄alkylthiocarbonyl-C₁-C₄alkyl, or

the group

C₁-C₄ alkyl - S - C - CH - O - C - C₁-C₄ alkyl ;

R₃ is hydrogen or C₁-C₄alkyl; and

R₄ is hydrogen or C₁-C₄alkyl; which process comprises converting an isothiocyanate of formula II

wherein the substituents R₁ and R₂ are as defined for formula I, with a hexahydropyridazine of formula llI

into a compound of formula IV

which is then reacted with a compound of formula V

CYCl₂ (V), wherein Y is oxygen or sulfur, in the presence of a base.

16. A herbicidal and plant growth regulating composition comprising one or more benzothiazolone derivatives of formula I according to claim 1.

17. A composition according to claim 16 comprising from 0.1 % to 95 % of a compound of formula I according to claim 1.

18. A method of controlling undesirable plant growth, which comprises applying a compound of formula I according to claim 1, or a composition comprising such a compound according to claim 16, in an effective amount to the plants or to the locus thereof.

19. A method according to claim 18, which comprises applying the active ingredient in an amount of from 0.001 to 4 kg per hectare.

20. A method according to claim 18 for the selective pre- or post-emergence control of weeds in crops of useful plants.

21. A method of inhibiting plant growth, which comprises applying a compound of formula I according to claim 1, or a composition comprising such a compound according to claim 16, in an effective amount to the plants or to the locus thereof.