NL8000488A - 4-PHENYLTHIOALCANE SULFONANILIDS AND THEIR DERIVATIVES. - Google Patents

Description

Β-4-phenylthioalkanesulfonanilides and derivatives thereof.

The invention relates to alkane sulfonanilides, which are substituted in the para position by a phenylthio, phenylsulfinyl or phenylsulfonyl group, and are further substituted by halogen and / or trifluonethyl, and salts thereof acceptable for agriculture and horticulture . The compounds of the invention are active herbicides and plant growth modifiers. The invention also relates to herbicidal compositions containing said compounds, and to the use of the compounds for controlling and controlling the growth of higher plants.

More particularly, the invention relates to compounds of the general formula 1, wherein R represents an alkyl group of 1-4 carbon atoms or monohalogenmethyl (chloromethyl, bromomethyl, fluoromethyl or iodomethyl), A represents halogen or CF 2, B represents hydrogen or halogen and n represents 0-2, where when A is CF ^ and B is hydrogen R cannot represent methyl, and its salts acceptable for agriculture and horticulture, on preparations for killing and modifying the growth of higher plants, which preparations mainly consists of a compound of the invention dispersed in a diluent medium, the use of the compounds of the invention for modifying the growth of higher plants and for killing higher plants and methods of the preparation of the compounds of the invention.

The compounds of the formula I can form salts, ie compounds of the above 8000488 2 formula, in which H is replaced by a cation acceptable in agriculture or horticulture. These are generally metal, ammonium and organic amine salts and can be prepared by treating the acidic form of the compound with a suitable base under mild conditions. The metal salts of the present invention include alkali metal (e.g., barium, calcium, and magnesium) and heavy metal (e.g., zinc and iron) salts as well as other metal salts, such as aluminum. Suitable bases for use in the preparation of the metal salts include metal oxides, 10 hydroxides, carbonates, hydrogen carbonates, and alkoxides. Some salts can also be prepared by a cation exchange reaction (by reaction of a salt of the invention with an organic or inorganic salt in a cation exchange reaction). The organic amine salts include the salts of aliphatic (eg, alkyl), aromatic and heterocyclic amines, as well as those with a mixture of these types of amines. The amines useful in the preparation of the salts of the invention can be primary, secondary or tertiary and preferably contain no more than 20 carbon atoms. Such amines include, for example, morpholine, methylcyclohexylamine, glucosamine, amines derived from fatty acids, etc. The amine and ammonium salts can be prepared by reacting the acid form with the appropriate organic base or ammonium hydroxide. All types of the above-mentioned salts are acceptable in agriculture or horticulture, the salt selected depending on the particular intended application and the economy of the situation. Particularly useful are the alkali metal, alkaline earth metal, ammonium and amine salts.

The salts of the invention are frequently formed by reaction of the precursors in aqueous solution. This solution can be evaporated to give the salt of the compound, usually as a dry powder. In some cases it may be easier to use a non-aqueous solvent, such as an alcohol, acetone, etc. The resulting solution is then treated to remove the solvent, for example, by evaporation under reduced pressure.

The compounds of the invention can be 8000488 c. 5 3 are prepared according to methods 1 and 2 described below (see reaction schemes A and B).

Method 1.

Step (1) of method 1 is performed by heating equimolar amounts of a substituted 4-chloronitrobenzene and benzenethiol in a suitable solvent in the presence of an equimolar amount of base. The solvent is a solvent in which the reactants are soluble, such as a lower alkanol (for example, ethanol or methanol), dimethyl sulfoxide or dimethyl formamide. The base is an organic or inorganic base. Suitable organic bases are tertiary amines such as N, N-dimethylaniline, triethylamine, pyridine, alkoxides such as sodium ethoxide and the like. Suitable inorganic bases are alkali metal hydroxides, such as sodium and potassium hydroxide, calcium hydride and the like. The product is isolated by conventional methods.

The reaction of step (2) is a reduction of the nitro group of the intermediate substituted 4-phenylthio-nitrobenzene. Chemical or catalytic methods known in the art are successful. Raney nickel is a suitable catalyst for the reduction. The product is isolated using conventional methods.

The reaction of step (3) is the sulfonylation of the intermediate substituted 4-phenylthioaniline with sulfonyl chloride in the presence of a base. If 1-2 equivalents of sulfonyl chloride are used, a mixture of mono and bis (sulfonylated) product can be obtained, which can be used in step (4). A larger amount of the bis (sulfonylated) product can be formed if two or more equivalents of sulfonyl chloride are reacted in the presence of a strong base.

Suitable bases for the reaction of step (3) are organic and inorganic bases such as pyridine, triethylamine, dimethylcyclohexylamine and substituted pyridines and the like. Liquid bases in excess can be used to eliminate the use of a solvent. Stronger bases promote the formation of bis (sulfonylated) product over a mono (sulfonylation).

Step (4) is a partial hydrolysis of the intermediate bis (sulfonyl) compounds. A high yield is obtained in this reaction. Basic hydrolysis using a strong base, such as potassium hydroxide in ethanol, is used. On the other hand, the precursor of step (3) can be directly converted to the product of step (4) via a mono (sulfonylation) reaction using one or more equivalents of sulfonyl-10 chloride and one or more equivalents of base. This reaction is favored by a base weaker than pyridine, such as 3-bromo-pyridine.

Step (5) is performed using conventional oxidation methods, such as hydrogen peroxide in acetic acid, sodium meta periodate and the like. The sulfoxide compound (n = 1) is formed when equimolar amounts of the oxidizing agent and the reactant are used, while the sulfone (n = 2) is prepared directly using two moles (or a small excess) of the oxidizing agent per mole 20 reaction component.

Method 2.

The reaction of step (1) of method 2 involves the formation of the substituted 4-thiocyanoaniline from the corresponding aniline, generally using conventional means.

The reaction of step (2) involves the direct formation of the substituted 4-phenylthioaniline from the corresponding 4-thiocyanoaniline. This reaction involves the formation of a sodium capaptide from the thiocyano portion by reacting it with sodium sulfide in aqueous dimethylformamide, followed by arylation thereof (ie, by heating the aqueous dimethylformamide solution with cuprous oxide and an aryl halide). nide, preferably iodobenzene). This product is identical to the precursor of step (3) of method 1 and can be converted identically to the compounds of the invention.

The herbicidal activity of the compounds 8000488 r. t 5 according to the invention was determined by comparative tests on greenhouse plants. The application activities before and after the emergence of the plants were determined in a direct comparative test on selected weed species. The weeds listed below are 5 examples of weeds used in these tests.

Grasses:

Giant foxtail (Setaria faberi)

Cinnabar (Echinochloa crus-galli)

Blood Millet (Digitaria isochaemum) 10 Cultivated Grass (Agropyron repens)

Yellow nut sedge (Cyperus esculentus)

Broad-leaved plants:

Red goosefoot (Amaranthus retroflexus)

Purslane (Portulaca oleracea) 15 Wild mustard (Brassica kaber)

Field bindweed (Convolvulus arvensis)

The chemicals under investigation are dissolved in a small amount of acetone or other suitable solvent and then diluted with water to obtain a concentration of 2000 ppm. Samples of this concentrate are diluted to obtain a final concentration of 500 ppm. 80 ml of this solution are added to a 15 cm jar containing the weed seeds to obtain a concentration equivalent to 20 pounds / acre. The use of 20 ml of this solution gives a concentration of 5 pounds / acre. All subsequent watering is accomplished from the bottom. Two pots per treatment are used. The observations are made 2-3 weeks after the treatment and recorded as the percent mortality at plant emergence for each species compared to the untreated control plants.

To determine the post-emergence application activity, the same weed mixes are grown for 2-3 weeks until the grassy crops are about 2.5-7.5 cm in length and the broad-leaved plants are about 2 in length. Possess 5-3.8 cm. They are sprayed with a 2000 ppm solution as described above for about 10 seconds or until good wetting of the blade surfaces.

The observations are made 2-3 weeks after treatment and recorded as the percent mortality for each species compared to the untreated control plants.

The compounds of the invention are generally active as herbicides. The mechanism or mechanisms by which this herbicidal activity is effected is currently unknown. However, the compounds of the invention also exhibit varying types of plant growth modifying activities. The plant growth modification as defined herein consists of all deviations from natural development, eg defoliation, stimulation, growth inhibition, growth retardation, dehydration, sedation, dwarfism (withering away), regulation and the like. This growth growth modifying activity is generally observed when the compounds of the invention begin to interfere with certain processes within the plant. If these processes are essential, the plant will die if treated with a sufficient amount of the compound. However, the observed type of the growth modifying activity varies with the types of the plants.

For application to plants, the compounds can be finely divided and suspended in any conventional aqueous media. In addition, spreaders, wetting agents, adhesives or other additives can be added if desired. Dry powders, as such or diluted with inert materials, such as diatomaceous earth, can also be used as dust materials (spray materials) for this purpose. The compositions are applied to the plants or the soil is covered therewith when control against emergence of the plants is desirable. The application is carried out with the help of usual sprayers, spray guns and the like. Application rates are generally 0.5-20 pounds / acre, but these rates may be increased or decreased depending on the individual application conditions. 8000488

It «7 things.

The compounds of the invention may advantageously be combined with other known herbicides to broaden or maximize the oh weed spectrum controlled by the herbicidal compositions of the invention or to control a weed which is not well controlled by the specific compounds according to the invention, better to combat. These other known herbicides include the phenoxy herbicides, for example 2.4-D, 2.4.5-T, silvex and the like, carbamate herbicides, thio-10 carbamate and dithiocarbamate herbicides, substituted urea herbicides, for example diuron, monuron and such triazine herbicides, for example simazine and atrazine, chloroacetamide and chlorinated aliphatic acid herbicides, chlorinated benzoic and phenylacetic acid herbicides, paraquat, nitraline and the like.

Furthermore, the herbicidal compositions containing the compounds of the invention may additionally contain nematocides, fungicides, insecticides, fertilizers, trace metals, soil conditioners, other plant growth regulators and the like.

These combinations are within the scope of the invention.

The invention is further illustrated but not limited by the following examples, wherein, unless otherwise indicated, the parts are parts by weight.

Example I

2-Nitro-5-phenylthiobenzotrifluoride.

A solution of 2-nitro-5-chlorobenzotrifluoride (28.8 g, 0.15 mol), benzenethiol (16.6 g, 0.15 mol) and ethanol (150 ml) is heated in a nitrogen atmosphere to the reflux temperature. To this solution is slowly added a solution of sodium hydroxide (6 g, 0.15 mol) and water (7 ml) at such a rate that reflux continues without external heating. The solution is then heated to reflux for an additional 2 hours, filtered hot, and the filtrate cooled. The resulting precipitate is collected by filtration and recrystallized from hexane to obtain a yellow solid; melting point = 65-67 ° C.

8000488 8

Analysis:

Calculated for Cj ^ HgFgNC ^ S: C 52.2, H 2.7, N 4.7%

Found: C 52.2, H 2.6, N 4.7 Z.

The following compound can be prepared using the same general method: 2-chloro-4-phenylthionitrobenzene, a solid.

Example II

4-Phenylthio-2-trifluoromethylaniline.

2-Nitro-5-phenylthiobenzotrifluoride 10 (25.6 g, 0.86 mol) in ethanol (500 ml) is reduced over

Raney nickel at about 3.15 kg / cm hydrogen gas. After the hydrogen uptake is complete, the mixture is deactivated with elemental sulfur, filtered and the filtrate evaporated under reduced pressure to yield the product in the form of an oil. The infrared spectrum shows an absorption at 2.9 um (strong Nï-band). The product crystallizes on standing to a solid; melting point = 63-66.5 ° C.

The following compound can be prepared using the same general method: 2-chloro-4-phenylthioaniline, a solid.

Example III

2-Bromo-4-phenylthioaniline.

A solution of 2-bromo-4-thiocyanoaniline (91.6 g, 0.4 mol) and dimethylformamide is added dropwise to a solution of sodium sulfide (0.48 mol) and water in a nitrogen atmosphere and the resulting solution is heated at 50 ° C for 1 hour. Cuprous oxide (34.33 g, 0.24 mol) and iodo-benzene (97.9 g, 0.48 mol) are added and the mixture is heated at a heating bath temperature of 150 ° C for 4.5 hours. The reaction is stopped by adding water, methylene chloride is added and the resulting mixture is filtered through a filter aid to remove suspended solids. The aqueous and organic layers are separated and the aqueous layer is extracted three times with methylene chloride. The methylene chloride extracts are combined, washed with water and dried. By removing the 8000488 * -> 9 desiccant and methylene chloride, the desired product is obtained, of which a purified sample melts at 61-63 ° C.

Analysis:

Calculated for C 14 H 25 BrNS: C 51.44, H 3.6, N 5.0%. Found: C 51.9, H 3.6, N 5.0%.

The following compounds can be prepared using the same general procedure: 2-chloro-4-phenylthioaniline, a solid, 2-fluoro-4-phenylthioaniline, a solid, 2,3-dichloro-4-phenylthioaniline, a solid, 2,5-dichloro-4-phenylthioaniline, a solid.

Example IV

N-chloromethylsulfonyl-4-phenylthio-2-trifluoromethylchloromethanesulfonanilide.

Chloromethanesulfonyl chloride (18.6 g, 0.125 mol) is added dropwise to a cold (0-5 ° C) stirred solution of 4-phenylthio-2-trifluoromethylaniline (13.5 g, 0.05 mol) in pyridine (20 g , 0.25 mol). The solution is stirred at room temperature overnight, poured into ice water and 12N. hydrochloric acid with stirring to give N-chloromethylsulfonyl-4-phenylthio-2-trifluoromethylchloromethanesulfonanilide in the form of an oil.

The following compound can be prepared using the same general method: N-methylsulfonyl-2-chloro-4-phenylthiomethanesulfonanilide, a solid.

Example V

4-Phenylthio-2-trifluoromethylchloromethanesulfonanilide.

A solution of N-chloromethylsulfonyl-4-30 phenylthio-2-trifluoromethylchloromethanesulfonanilide and 85% potassium hydroxide (0.15 mol) in ethanol (200 ml) is stirred at room temperature overnight. The solvent is removed by filtration under reduced pressure and the solid product is taken up in hot water, filtered and then acidified with dilute hydrochloric acid. The product is taken up in methylene chloride and dried. By removing the drying agent and solvent, an oil which crystallizes on standing is obtained. Recrystallization from methylene chloride-hexane gives a beige solid; melting point »97-99 ° C.

Analysis; 5 Calculated for C ^ Hj JCIF2NO2S2: C 44.0, H 2.9, N 3.7%

Found: C 44.0, H 2.9, N 3.7%.

The following compound can be prepared using the same general method: 2-chloro-4-phenylthiomethanesulfonanilide, a solid.

Example VI

2-Bromo-4-thiocyanoaniline.

To a cold (0-5 ° C) stirred solution o-bromoaniline (20.6 g, 0.12 mol) and sodium thiocyanate (29.2 g, 0.36 mol) in methanol (300 ml) is added dropwise. solution of bromine (19.5 g, 0.122 mol) in methanol (75 ml), saturated with sodium bromide. The solution is stirred for 1 hour after the addition of the bromine and then poured into water (2 liters) and neutralized with sodium carbonate. The resulting solid is collected, washed with water and dried; melting point 20 = 74-79 ° C,

The following compounds are prepared using the same general method: 2-chloro-4-thiocyanoaniline, m.p. 63-65 ° C, 2-fluoro-4-thioeyanoaniline, mp. = 34-35 ° C, 2.5-dichloro-4-thiocyanoaniline, mp. Mp 111-115 ° C, 2,3-dichloro-4-thiocyanoaniline, mp. 132-137 ° C.

Example VII

2-Bromo-4-phenylthiomethanesulfonanilide.

Methanesulfonyl chloride (26.9 g, 0.23 mol) is added dropwise to a cold (0-5 ° C) solution of 2-bromo-4-phenylthioaniline (52.5 g, 0.187 mol) in 3-chloropyridine (163 g), and the solution is warmed to room temperature and stirred overnight. A further amount of methanesulfonyl chloride (7 g) is added and the reaction mixture is heated at 50 ° C for 24 hours. The reaction mixture is mixed with dilute hydrochloric acid and then three times 9000488. 11 extracted with methylene chloride. The methylene chloride extract is washed three times with water and dried. By removing the desiccant and methylene chloride, the desired product is obtained in crude form. This product is leached with hexane and the residue is chromatographed on silica gel using methylene chloride as the eluent. The methylene chloride eluent is removed by evaporation to give a solid which is recrystallized from hexane methylene chloride; mp 74.5-75 ° C.

10 Analysis:

Calculated for Gj: ^ ^ »58, H 3.38, N 3.91%

Found: C 43.7, H 3.4, N 3.9%.

The following compounds are prepared using the same general method: 2-chloro-4-phenylthiomethanesulfonanilide, m.p. = 79.5-81 ^ 0.2-fluoro-4-phenylthiomethanesulfonanilide, m.p. 125-125.5 ° C,

The following compounds are also prepared using the same general method with the exception that chloromethanesulfonyl chloride or ethanesulfonyl chloride are used: 2-bromo-4-phenylthiochloromethanesulfonanilide, m.p. = 71-72.5 ° C, 2-chloro-4-phenylthiochloromethanesulfonanilide, mp = 73-74 ° C, 2-fluoro-4-phenylthiochloromethanesulfonanilide, mp. 83-83.5 ° C, 2,3-dichloro-4-phenylthiochloromethanesulfonanilide, mp. -25 122-123.5 ° C, 2,5-dichloro-4-phenylthiochloromethanesulfonanilide, mp. 144-144.5 ° C, 4-phenylthio-2-trifluoromethyl-ethanesulfonanilide, a solid.

Example VIII

4-Phenylsulfinyl-2-trifluoromethylchloromethanesulfonanilide.

To a stirred solution of 4-phenyl-thio-2-trifluoromethylchloromethanesulfonanilide (2.6 g, 0.0068 mol) in glacial acetic acid (15 ml) is added 30% hydrogen peroxide (0.77 g, 0.0068 mol). The solution is stirred at room temperature overnight, heated exactly to reflux and then treated with water. The aqueous mixture is filtered off, and the tan solid is washed with water and dried; mp. 146-150 ° C.

Analysis:

Calculated for C 21 H 18 ClF 2 O: C 42.2, H 2.8, N 3.5%. Found: C 42.3, H 3.0, N 3.6%.

The following compounds are prepared using the same general procedure: 2-chloro-4-phenylsulfinylmethanesulfonanilide, m.p. 129-129.5 ° C, 2-fluoro-4-phenylsulfinylmethanesulfonanilide, mp. 121-122.5 ° C, 10 2-bromo-4-phenylsulfinylmethanesulfonanilide, mp. 138-138.5 ° C, 2-fluoro-4-phenylsulfinylchloromethanesulfonanilide, mp. -185-185.5 ° C, 2-bromo-4-phenylsulfinylchloromethanesulfonanilide, mp. 123.5-124 ° C, 2-chloro-4-phenylsulfinylchloromethanesulfonanilide, mp. 142-143 ° C,

4-phenylsulfinyl-2-trifluoromethyl-ethanesulfonanilide, a solid. Example IX

4-Ε6 ^ ΐ3α1ίο ^ 1-2-ίΓίί1ηο: πιΐ6ί1 ^ 1ο1ι1οοπα6ίΤ ^ 3η3Ό.1ίο ^ ηί1ίά6.

To a stirred solution of 4-phenylthio-2-trifluoromethylchloromethanesulfonanilide (2.6 g, 0.0068 mol) in glacial acetic acid (15 ml) is added 30% hydrogen peroxide (3 g, 0.0272 mol). The solution is heated to reflux for 3 hours, water is added and the mixture is cooled. The resulting precipitate is collected by filtration, washed with water and dried to yield a white solid; melting point = 93-97 ° C.

Analysis:

Calculated for C 21 H 21 CIF NO NO 4: C 40.6, H 2.7, N 3.4%. Found: C 40.6, H 2.8, N 3.5%.

The following compounds are prepared using the same general method: 2-chloro-4-phenylsulfonylmethanesulfonanilide, a solid, 2-bromo-4-phenylsulfonylmethanesulfonanilide, mp. 159-160 ° C, 35 2-bromo-4-phenylsulfonylchloromethanesulfonanilide, mp. 136-136.5 ° C, 8000488 13 2-fluoro-4-phenylsulfonylmethanesulfan nanilide, mp. 127.5-128 ° C, 2-chloro-4-phenylsulfonylmethanesulfonainl, m.p. 152-156 ° G, 2-chloro-4-phenylsulfonylchloromethanesulfonanilide, 5 mp. 142-142.5 ° C, 2-fluoro-4-phenylsulfonylchloromethanesulfonanilide, mp. 142-142.5 ° C, 4-phenylsulfonyl-2-trifluoromethyl-ethanesulfonanilide, a solid.

10 8000488

Claims (10)

1. Compounds of general formula 1, wherein R represents alkyl of 1-4 carbon atoms or monohalo-methyl, A represents halogen or CF ^, B represents hydrogen or 5 halogen and n represents 0-2, where when A is CF ^ and B is hydrogen R cannot represent methyl, and salts thereof acceptable for use in agriculture or horticulture. Compounds according to claim 1, characterized in that n is 0. Compounds according to claim 1, characterized in that η is 1. Compounds according to claim 1, characterized in that n is 2. Compounds according to claim 1, characterized in that R represents -CH 1 Cl. Compounds according to claim 1, characterized in that A represents -CF ^. Compounds according to claim 1, characterized in that A represents halogen. A method of modifying the growth of plants, characterized in that one or more compounds according to claims 1-7 are used. 9. Preparation for modifying the growth of higher plants, characterized in that it contains one or more compounds as defined in claims 1-7 dispersed in a diluent medium acceptable for agriculture or horticulture. 10. Compounds, preparations and methods as described in the description and / or examples. 30 8000488 NHSOdR ^ -0 —A- “s ~ 0! O p) ii NHS02R NHSOeR n (S02R) 2 • ώ ~ W Β: φ ~ w ~“ "Φ s (0Lt) st) -B- SC» sQ 8000488 Minnesota Mining and Manufacturing Company, of St. Paul, Minnesota, USA St. v. America.