WO1987007606A1 - Herbicidal sulfonamides - Google Patents

Abstract

Specific sulfonamides show particular utility as selective pre-emergent and/or post-emergent herbicides.

Description

Title HERBICIDAL SULFONAMIDES Background of the Invention This invention relates to specific sulfon- amides, their agriculturally suitable compositions, and their raethod-of-use as a selective pre-emergent and/or post-emergent herbicide.

The compounds of this invention are generically disclosed in European Patent Application EP-A-107,979 which was published May 9. 1984. disclosing herbicidal sulfonylureas of the formula:

wherein

R₁ is H. F. Cl. Br. CH₃, OCH₃ , CF₃. SCH₃. or

OCF H; R is H or C -C alkyl; n is 0 or 1; w is o or S; R is H or CH_:

Z is CH. N, CCH- ■i. CC«_.H_b. CC1 or CBr;

X is CH . OCH₃. C₂H₅. Cl. F, Br. OCF₂H. CH₂F or CF : and

Y is, inter alia. H. CH₃. OCH₃. OC^. CH₂OCH₃.

NH . etc.

Compounds I and II are also generically disclosed in South African Patent Application 83/5165. published 1/16/84. which discloses herbicidal sulfonamides of formula

wherein

A is an unsubstituted or substituted bridge of

3 or 4 atoms which contains 1 or 2 oxygen, sulfur or nitrogen atoms and. together with the linking carbon atom, forms a non-aromatic

5- or 6-membered heterocyclic ring system. with the proviso that two oxygen atoms are separated by at least one carbon atom and that oxygen and sulfur atoms are only linked to -each other if the sulfur atom takes the form of the -SO- or SO - group, and R is hydrogen, halogen, nitro. C,-C alkyl, C.-C. haloalkyl. C -C alkoxy, C,-C haloalkoxy.

C -C alkoxycarbonyl. C,-C alkylthio,

C1-C4„ alkylεulfinyl. C1-C4_Λ alkylεulfonyl or

C -C alkoxyalkoxy;

R , is H. ha logen , NO_ . C. -C . alkyl . C, -C . 1 2 1 4 1 4 haloalkyl. C,-C alkoxy. C,-C haloalkoxy,

C,-C alkoxycarbonyl, C,-C alkylthio,

C -C alkylsulfinyl, C,-C alkylsulfonyl or C Δ_-C_cb alkoxyalkoxy;

R and R . each independently of the other, are hydrogen, C,-C alkyl. C,-C alkoxy. C,-C haloalkoxy, C^_^-C. haloalkylthio,

alkylthio. halogen. Cώ_-C_cb alkoxyalkoxy or NR..Ro.. wherein R_b and Ro, are hydrogen or

C,-C alkyl; and E is CH or N. Despite the broad teachings of these two disclosures, there is still a need for specific compounds which demonstrate selectivity as pre-emergent and/or post-emergent herbicides.

Summary o£ the Invention According to the instant invention such compounds have unexpectedly been found. The invention relates to the compounds of Formula I and Formula II. their agriculturally suitable compositions, and their method-of-use as selective pre-emergent and/or post-emergent herbicides, particularly for use in sugar beets.

I - R is CH CH,CH₂CH₃, R, is OCH₃ ii - is CH₂CH₂CH₃. R_L is CH₃

Compound I is 2-butyl-N-[(4.6-dimethoxy- py iraidin-2-yl)-aminocarbonyl]-2.3-dihydro-5-methoxy- 1.2-benzisothiazole-7-sulfonamide. S.S-dioxide, m.p. 174-176°C.

Compound II is 2-propyl-N-[ (4,6-dimethoxy- pyrimidin-2-yl)-aminocarbon l]-2.3-dihydro-5-meth 1- 1.2-benzisothiazole-7-εulfonamide. S,S-dioxide. p 208-212°C. Detailed Descripion of the Invention The compounds of Formula I and Formula I I can be prepared by the method described in Equation 1.

Equation 1

I I I IV

X or II

The sulfonyl isocyanates of Formula III are reacted with the aminopyri idine of Formula IV in an inert solvent such as dichloromethane. acetonitrile, xylene or chlorobenzene. for a period of 1 to 96 hours at temperatures of 20° to 100°C. The product of Equation 1 can be isolated either by filtration or by evaporation of the reaction solvent and trituration with a solvent such as 1-chlorobutane, ether or similar solvents.

The sulfonyl isocyanates of Formula III can be prepared by methods, or modifications thereof, obvious to one skilled in the art as described in U.S. Patent 4.379.769. The compounds of Formula I and Formula II can also be prepared by the method shown in Equation 2 by reacting the sulfonamides of Formula V with the phenylcarbamate of Formula VI in the presence of a molar equivalent of 1.8-diazabicyclo[5.4.0]undec- 7-ene. The phenylcarbamate of Formula VI can be prepared by the reaction of the aminopyrimidine IV with diphenyl carbonate in the presence of a base such as sodium hydride or. alternatively, by the reaction of the aminopyrimidine of Formula IV with phenyl chloro ormate in the presence of an acid acceptor such as pyridine or triethylamine.

Equation 2

y_ i

Also, the compounds of Formula I and Formula II can be prepared, as shown in Equation 3. by reacting the aminopyrimidine of Formula IV with the phenyl¬ carbamate of Formula VII at temperatures of 25° to 100°C in solvents such as dioxane, acetonitrile or tetrahydrofuran for a period of (about) 1 to 24 hours. The phenylcarbamate of Formula VI can be prepared by reaction of the sulfonamide V with phenyl chloroformate in the presence of a base such as pyridine or sodium hydroxide. Eq uation 3

VI I The sulfonamide of Formula Va can be prepared starting with the t-butylsulfonamide of Formula Villa as shown in Equation 4.

Equation 4

Villa IX

XI

XII

XIII

XIV

Va

Similarly, the sulfonamide Vb can be prepared according to the procedure of Equation 4 by starting with the t-butylsulfonamide Vlllb. In this case, it is not necessary to form the sulfoxide. Oxidative cnlorination is carried out using the sulfide.

Vb VHIb

The aminopyrimidine of Formula IV can be pre¬ pared by methods obvious to one skilled in the art. For a review of the syntheses and reactions of 2-aminopyrimidines, see The Chemistry of Heterocvclic Compounds. Vol. 16. John Wiley and Sons (1962).

Agriculturally suitable salts of the compounds of Formula I and Formula II are also useful herbicides and can be prepared in a number of ways known to the art. For example, metal salts can be made by contacting the compounds of Formula I or Formula II with a solution of an alkali or alkaline earth metal salt having a sufficiently basic anion (e.g.. hydroxide, alkoxide or carbonate). Quaternary amine salts can be made by similar techniques.

Salts of the compounds of Formula I or Formula II can also be prepared by exchange of one cation for another. Cationic exchange can be effected by direct contact of an aqueous solution of a salt of the compound of Formula I or Formula II (e.g., an alkali metal or quaternary amine salt) with a solution containing the cation to be exchanged. This method is most effective when the desired salt containing the exchanged cation is insoluble in water and can be separated by filtration.

Exchange may also be effected by passing an aqueous solution of a salt of the compounds of Formula I and Formula II (e.g.. an alkali metal or quaternary amine salt) through a column packed with a cation exchange resin containing the cation to be exchanged for that of the original salt and the desired product is eluted from the column. This method is particu- larly useful when the desired salt is water-soluble. Acid addition salts, useful in this invention, can be obtained by reacting the compounds of Formula I or Formula II with a suitable acid {e.g., p.-toluenesulfonic acid, trichloroacetic acid or the like) .

The preparation of the compounds of this invention is further illustrated by the following examples wherein temperatures are given in degrees Celsius unless otherwise designated.

Example 1 2-Propylthio-4-methoxy-N-(l,l-dimethylethyl)benzene- sulfonamide

To 4-methoxy-N-(l.l-dimethylethyl)benzenesulfon- amide (100 g) stirring at -78° in tetrahydrofuran (1 L) under nitrogen was added dropwise 1.55 M n-butyllithium (0.584 L) . The reaction mixture was allowed to warm to room temperature and stirred for 1 hour at that temper¬ ature. The solution was then re-cooled to -78° and dipropyldiεulfide (0.0711 L) was added dropwise. The reaction mixture was allowed to warm to room temperature and stirred overnight. The whole mixture was poured into water and extracted with ether. The ethereal solu¬ tion was washed successively with water and saturated sodium chloride solution, dried over sodium sulfate and concentrated jLri vacuo to yield 105.5 g of the title compound, m.p. 84-88°. Example 2 2-(l,l-Pimethylethyl)-2.3-dihydro-5-m thoxy-7-(propyl- thio)-1.2-be zisothiazol-3-ol-l,1-dioxide

A solution 2-propylthio-4-methoxy-N-(l,1-dimethyl- ethyl)benzeneεulfonamide (250.42 g) in tetrahydrofuran (1.5 L) was cooled to 0° and n-butyllithium was added cautiously with stirring of the solution under a nitrogen atmosphere. The reaction mixture was allowed to warm to room temperature and stirred for 1.5 hours. After this time, it was cooled to -78° and N.N-dimethyl- formamide (0.184 L) was added dropwise. The mixture was allowed to warm to room temperature and stir overnight. The whole was quenched with water and the aqueous mix¬ ture extracted with ethyl acetate. The organic layer was washed with water and saturated sodium chloride solution and dried over sodium sulfate. The solvent(s) was removed by rotary evaporation and the crude oily product triturated with butyl chloride to give.149 g of the title compound as a yellow solid, .p. 99-102°. Example 3

5-Methoxy-7-(propylthio)-l,2-benzisothiazole-l,1-dioxide

Benzene (0.40 L) containing 2-(l,1-dimethyl- ethyl)-2,3-dihydro-5-methoxy-7-(propylthio)-1,2-benz- isothiazol-3-ol-l.1-dioxide (147.2 g) and jj-toluene- sulfonic acid (1.5 g) was azeotroped for 5 hours. After this time. 7.9 mL of water had been collected. The reaction mixture was allowed to cool and the crude product was collect-ed by filtration. Trituration with ri-butyl chloride gave 63.5 g of the title compound as _a yellow solid, m.p. 109-113°.

Example 4 2,3-Dihydro-5-methoxy-7-(propylthio)-l.2-benziεothiazole- 1.1-dioxide

5-methoxy-7-(propylthio)-1.2-benzisothiazole-l.1- dioxide (83 g) was suspended in ethanol/tetrahydrofuran (1:0.4 L) and cooled to 0°. Sodium borohydride (11.60 g) was added in portions to the cool stirred suspension and the resulting solution was allowed to warm to room temperature and stirred overnight. Acetic acid (0.06 L) was added and a white precipitate formed. The precipitate was collected by filtration, washed with water and dried to yield 68 g of the title compound as a white solid, m.p. 85-89°.

Example 5 2-Butyl-2.3-dihydro-5-methoxy-7-(propylthio)-1.2-benz- isothiazole-1,1-dioxide

Powdered potassium carbonate (15.2 g) was suspended in ethanol (0.20 L) and 2,3-dihydro-5-methoxy- 7-(propylthio)-1.2-benzisothiazole-l.1-dioxide (20.0 g) and 1-iodobutane (excess) were added. The reaction mixture was refluxed overnight and its course was moni¬ tored by TLC. After this time, the whole mixture was poured into water, acidified with 10% hydrochloric acid solution and extracted with 1-chlorobutane. The organic layer was washed with water, dried over sodium sulfate and concentrated j vacuo to yield 20 g of the subject compound as a yellow oil.

Example 6 2-Butyl-2,3-dihydro-5-methoxy-7-(propylsulfinyl)-1,2- benzisothiazole-l.l-dioxide

To 2-butyl-2,3-dihydro-5-methoxy-7-(propylsul- finyl)-1.2-benzisothiazole-l.1-dioxide (20.0 g) in methylene chloride (0.20 L) at 0° was added m-chloro- peroxybenzoic acid (13.0 g) in methylene chloride (0.10 L). The reaction mixture was stirred at 0° for 0.5 hours and saturated sodium sulfite (0.010 L) was added. The whole mixture was poured into water and extracted with methylene chloride. The organic layer was washed 2X with saturated sodium bicarbonate solu- tion. water and saturated sodium chloride solution. The extract was dried over sodium sulfate. concentrated in vacuo and triturated with hexane/1-chlorobutane mixture to yield 14.0 g of the title compound as a semisolid. f ^' Example 7

2-Butyl-2,3-dihydro-5-methoχy-1.2-benzisothiazole-7- sulfonamide- .1-dioxide

2-Butyl-2,3-dihydro-5-methoxy-7-(propylsulfinyl)- 1.2-benzisothiazole-l.l-dioxide (19.0 g) was dissolved in propionic acid and cooled to -20°. Water (1.5 mL) and then liquid chlorine (4.4 mL) are added. The reaction mixture was stirred at -20° for 0.5 hours then allowed to warm to room temperature. The reaction mixture was poured into ice and water and extracted with ethyl acetate. The extracts were washed 3 times with saturated sodium bicarbonate, then with saturated sodium chloride solution, dried over sodium sulfate and concentrated ii vacuo to yield the sulfonyl chloride as a pale yellow oil. The whole was dissolved in ethyl- ene chloride, cooled to -40° and liquid ammonia (3.4 mL) was added dropwise. The reaction mixture was allowed to warm gradually to room temperature, after which the mixture was poured into water, acidified with 10% hydro¬ chloric acid solution and extracted with ethyl acetate. The organic layer was washed with water and saturated sodium chloride solution, dried over sodium sulfate and concentrated by rotary evaporation to yield 9.26 of the title compound as a white solid, m.p. 164-166°.

Example 8 2-Butyl-N-r (4.6-dimethoxypyrimidin-2-yl)amino- carbonyl1-2.3-dihydro-5-methoxy-l.2-benzisothiazole-7- sulfonamide, S.S-dioxide

To a stirred solution of 2-butyl-2,3-dihydro-5- methoxy-1,2-benzisothiazole-7-sulfonamide-1,1-dioxide (0.5 g) and 1.8-diazabicyclo[5.4.0]undec-7-ene (0.22 mL) in acetonitrile (3.0 mL) was added phenyl-(4.6-dimeth- oxy-2-pyrimidin-2-yl)carbamate (0.41 g). The reaction mixture was stirred at room temperature for 1 hour. After this time, water (6.0 mL) and 10% hydrochloric acid solution were added. The resulting precipitate was collected by filtration, washed 3 times with water and vacuum dried to yield 0.68 g of the subject compound as a white solid, m.p. 174-176°.

Example 9 N-(l, 1-Dimethylethyl)-4-methyl-2-(propylthio)-benzene- sulfonamide

To a solution of 50 g (.22 m) of N-(l.1-dimethyl- ethyl)-4-methyl-benzenesulfonamide in 875 ml of anhydrous THF. 312 ml (.48 m) of a 1.55 M solution of n-BuLi in hexane was added dropwise at -78°C. After the addition was complete, the reaction mixture was allowed to warm to room temperature. After 1.5 hr.. trie resulting yellow suspension was cooled to -75°C and 38 ml (.24 m) of propyl disulfide added dropwise. warming to -15°C for 1 hr. , then stirring overnight at room temperature resulted in a white suspension. This was poured into water and extracted with ether. The organic extracts were washed twice with water, then brine and dried. Concentration gave a white solid which was washed with hexane to provide 58.8 g of the subject compound, m.p. 98-101°C.

NMR (d6-DMSO) 1.02 (m. 3. CH₃)

1.08 (s, 9, t-Bu); 1.45-1.90 (m. 2); 2.35 (S. 3. ArCH₃) 2.90-3.18 (t. 2. SCH₂)

7.01-7.21 (m. 2. ArH) ; 7.38 (br. s. 1. NH) ; 7.75-7.90 (d. 1. ArH). Example 10 2.3-Dihydro-5-methy1-7-( ropylthio)-!.2-benzisothia- zole. 1,1-dioxide

To a solution of 116 g (.387 m) of the above sulfonamide in 875 ml anhydrous THF, 531 ml (.850 ) of a 1.6 M solution of n-BuLi in hexane was added drop¬ wise at -45°C. After the addition was complete, the reaction mixture was allowed to warm to room temperature. ^• After 1 hr., the mixture was cooled to -73°C and 90 ml (1.16 ) of DMF (dimethylformamide) added dropwise at -78°C. After warming and stirring at room temperature for 1 hr.. the mixture was poured into water and extracted with ethyl acetate. The combined organic extracts were washed with water, then brine and dried. Concentration gave 2-(l.l-dimethyl- ethyl)-5-methyl-7-(propylthio)-l,2-benzisothiazol-3-ol as a viscous orange oil.

This oil was dissolved in 200 ml benzene and 1.2 g (6.3 mm) p-toluenesulfonic acid added. The solution was azeotroped for 36 hr. and 5.5 ml of water^' removed. The solution was cooled and hexane added to precipitate 51.3 g of 5-methyl-7-(propylthio)-1.2- benzisothiazole, 1.1-dioxide as a yellow solid, mp 101- 106°C. A second crop was obtained and the combined crops recrystallized from 500 ml n-BuCl to provide 57.5 g of the desired benzisothiazole.

To a suspension of 56.5 g (.22 ) of this benzisothiazole in 475 ml ethanol and 200 ml THF at 0°C. 8.3 g (.22 ) of sodium borohydride was added in portions. The mixture went to a homogeneous yellow solution, then a thick white precipitate appeared. The mixture was warmed to room temperature and stirred for 2.5 hr. Acetic acid was added dropwise to destroy any excess sodium borohydride. After gas evolution stopped, the mixture was poured into ice/water. The resulting precipitate was collected by filtration and washed twice with water. The solid was dried over¬ night in a vacuum oven at 40°C to provide 54.5 g of the subject compound as a white solid, m.p. 110-113°C. NMR (d6-DMSO) 0.99 (t, 3. CH₃) ;

1.63 (m, 2) ;

2.40 (S. 3..CH3);

3.08 (t, 2. SCH );

4.28 (S. 2);

7.11 (S. 1);

7.32 (S. 1).

Example 11

2 , 3-Dihydro-5-methyl-2-propyl-7-(propylthio)-l,2- benzisothiazole, 1.1-dioxide

A mixture of 7.10 g (27.3 mm) of the above propylthio benzisothiazole, 5.3 ml (54.6 mm) of n-propyl idodide, 11.3 g (81.9 mm) of potassium carbonate, and 100 ml of ethanol was refluxed overnight. After cooling, the mixture was poured into water, a^'cidified with 10% HCl and extracted with ethyl acetate. The combined organic extracts were washed . . . with water, brine and dried. Concentration gave 8.36 g of the subject compound as a yellow oil.

NMR (CDC13) 0.94-1.09 (m. 6);

1.06-1.84 (m, 4); 2.38 (s. 3, AπCH₃); 2.99 (t. 2) ; 3.19 (t, 2);

4.21 (s. 2. ArCH₂N); 6.92 (s. 1. ArH); 7.15 (S. 1. ArH).

Example 12

2 , 3-Dihydro-5-methyl-2-propyl-l,2-benzisothiazole-7- . . sulfonyl chloride. 1,1-d oxιde

To a 15°C solution of 8.36 g (28 mm) of the above 2-propyl benzisothiazole in 100 ml acetic acid

1.26 ml (70 mm) of water was added followed by the dropwise addition of 6.5 ml (14 mm) of chlorine gas.

The solution was allowed to warm to room temperature.

After 1.5 hr.. the yellow suεpenεion was poured into ice/water. The resulting white precipitate was collected by filtration and washed with water to

5 provide 6.5 g of the subject compound, m.p. 131-135°C.

NMR (d6-DMSO) 0.93 (t. 3. CH₃) I

1.45-1.85 (m. 2):

2.44 (S. 3, ArCH₃);

3.09 (t. 2. NCH₂):

4.28 (S, 2, ArCH₂N);

7.41 (S. 1, ArH); ____ — 0 7.70 (S. 1. ArH).

~- — Example 13

2.3-Dihydro-5-methyl-2-propyl-l.2-benzisothiazole-7- εulfonamide, 1,1-dioxide

To a εolution of 6.24 g (19.3 mm) of the above sulfonyl chloride. 100 ml methylene. chloride and 100 ml THF. at -78°C, 1.2 ml (48 mm) of ammonia gas was added dropwise. The resulting suspension was allowed to warm to 10°C. It was then poured into water, acidified with 10% HCl and extracted with ethyl ⁰ acetate. The resulting combined organic extracts were washed with water, then brine. Concentration gave

4.43 g of the subject compound as a white solid, m.p.

173-175°C.

NMR (d6-DMSO) 0.94 (t. 3. CH₃) ; 5 1.48-1.87 (m, 2. CH₂) ;

2.48 (S. 3. ArCH₃);

3.12 (t. 2. NCH₂);

4.43 (S. 2. ArCH₂N);

7.50 (S. 2. NH₂);

7.70 (s. 1, ArH);

7.89 (s. 1, ArH). ⁰ Example 14

2-Propyl-N-f ( , 6-dimethoxy-pyrimidin-2-yl)amino- carbony11-2 , 3-dihydro-5-methyl-l, 2-benzisothiazole-7- sulfonamide, S,S-dioxide

To a mixture of .5 g (1.65 mm) of the above ς . . sulfonamide. .45 g (1.65 mm) of N-[4, 6-dιmethoxypyrlmi- din-l-yl)aminocarbonyl] phenyl carbamate and 3 ml acetonitrile at ambient conditions. .25 ml (1.65 mm) of DBU was added dropwise. After 15 min.. 6 ml of water was added to the solution, then 10% HCl was added dropwise until a white precipitate formed. The resulting precipitate was collected by filtration and washed with water to provide .67 g of the subject compound as a solid, m.p. 208-212°C.

NMR (d6-DMSO) 0.86 (t. 3, CH₃) ; 1.52-1.68 (m. 2);

2.50 (s. 3. ArCH₃);

3.04 (t. 2 NCH₂);

3.91 (S. 6. OCH₃);

4.40 (s. 2. ArCH₂N);

5.96 (s. 1);

7.70 (s. 1. ArH)

7.96 (s. 1. ArH); 10.65 (S. 1. NH);

13.00 (s. 1. NH).

Formulations

Useful formulations of the compounds of Formula I and Formula II can be prepared in conventional ways. They include dusts, granules, pellets, 5 solutions, suspensions, emulsions, wettable powders, emulsifiable concentrates and the like. Many of these may be applied directly. Sprayable formulations can be extended in suitable media and used at spray volumes of from a few liters to several hundred liters

10 per hectare. High strength compositions are primarily used as intermediates for further formulation. The formulations, broadly, contain about 0.1% to 99% by weight of active ingredient(s) and at least one of (a) about 0.1% to 20% surfactant(s) and (b) about 1% to

1599.9% solid or liquid inert diluent(s). More specifically, they will contain these ingredients- in the following approximate proportions:

Table 1

2_Q Weight Percent*

Active Ingredient Diluent(s) Surfactant(s)

Wettable Powders 20-90 0-74 1-10

Oil Suspensions. 3-50 40-95 0-15

Emulsions. Solutions. 25 (including Emulsifiable Concentrates) Aqueous Suspension 10-50 40-84 1-20

Dusts 1-25 70-99 0- 5

Granules and Pellets 0 . 1-95 5-99 . 9 0-15

High Strength 90-99 0- 10 0-2 30 compositions

* Active ingredient plus at least one of a surfactant or a diluent equals 100 weight percent.

Lower or higher levels of active ingredient can. 35 of course, be present depending on the intended use and the physical properties of the compound. Higher ratios of. surfactant to active ingredient are some¬ times desirable, and are achieved by incorporation into the formulation or by tank mixing. Typical solid diluents are described in Watkins. et al.. "Handbook of Insecticide Dust Diluents and Carriers", 2nd Ed.. Dorland Books. Caldwell. New Jersey, but other solids, either mined or manufac¬ tured, may be used. The more absorptive diluents are preferred for wettable powders and the denser ones for dusts. Typical liquid diluents and solvents are described in Marsden, "Solvents Guide." 2nd Ed.. Interscience, New York, 1950. Solubility under 0.1% is preferred for suspension concentrates; solution concentrates are preferably stable against phase separation at 0°C. "MσCutcheon¹s Detergents and Emulsifiers Annual", MC Publishing Corp., Ridgewood. New Jersey, aε well as Siεely and Wood, "Encyclopedia of Surface Active Agents", Chemical Publishing Co., inc.. New York, 1964, list surfactants and recommended uses. All formulations can contain minor amounts of additives to reduce foaming, caking, corrosion, micro¬ biological growth, etc.

The methods of making such compositions are well known. Solutions are prepared by simply mixing the ingredients. Fine εolid compoεitions are made by blending and, usually, grinding as in a hammer or fluid energy mill. Suspensions are prepared by wet milling (see. for example. Littler. U.S. Patent 3,060,084). Granules and pellets may be made by spraying the active material upon preformed granular carriers or by agglomeration techniques. See J. E. Browning, "Agglomeration", Chemical Engineering, December 4. 1967. pp. I47ff. and "Perry's Chemical Engineer's Handbook". 5th Ed.. McGraw-Hill. New York, 1973. pp. 8-57ff. For further information regarding the art of formulation, see for example:

H. M. Loux, U.S. Patent 3,235,361. February 15. 1966, Col. 6, line 16 through Col. 7, line 19 and Examples 10 through 41;

R. W. Luckenbaugh. U.S. Patent 3,309.192, March 14, 1967. Col. 5. line 43 through Col. 7. line 62 and Examples 8, 12. 15. 39. 41. 52. 53, 58. 132. 138-140. 162-164. 166. 167 and 169-182: H. Gysin and E. Knusli, U.S. Patent 2,891,855. June 23, 1959, Col. 3. line 66 through Col. 5. line 17 and Examples 1-4;

G. C. Klingman. "Weed Control as a Science", John Wiley and Sons. Inc.. New York. 1961. pp. 81-96; and

J. D. Fryer and S. A. Evans. "Weed Control Hand¬ book". 5th Ed.. Blackwell Scientific Publications, Oxford. 1968. pp. 101-103.

In the following examples, all parts are by weight unless otherwise indicated.

Example 15 Wettable Powder

2-Butyl-N-[ (4,6-dimethoxypyri idin-2-yl)amino- carbonyl]-2.3-dihydro-5-methoxy-l.2-benziso- thiazole-7-εulfonamide, S.S-dioxide 80% εodium alkylnaphthaleneεulfonate 2% sodium ligninsulfonate 2% synthetic amorphous silica 3% kaolinite 13% The ingredients are blended, hammer-milled until all the solids are essentially under 50 microns, re- blended, and packaged. Example 16 Wettable Powder

2-Propyl-N-[ (4.6-dimethoxy-pyrimidin-2-yl)amino- carbonyl]-2.3-dihydro-5-meth l-l,2-benziso- thiazole-7-sulfonamide, S,S-dioxide 50% sodium alkylnaphthalenesulfonate 2% low viscosity methyl cellulose 2% diatomaceous earth 46%

The ingredients are blended, coarsely hammer- milled and then air-milled to produce particles essen¬ tially all below 10 microns in diameter. The product is reblended before packaging.

Example 17 Granule Wettable Powder of Example Above 5% attapulgite granules 95%

(U.S.S. 20-40 mesh; 0.84-0.42 mm) A slurry of wettable powder containing 25% solids is sprayed on the surface of attapulgite granules in a double-cone blender. , The granules are dried and packaged.

Example 18 Extruded Pellet

2-Butyl-N-[(4.6-dimethoxypyrimidin-2-yl)amino- carbonyl]-2.3-dihydro-5-methoxy-l.2-benziso- thiazole-7-εulfonamide. S.S-dioxide 25% anhydrouε sodium sulfate 10% crude calcium ligninsulfonate 5% sodium alkylnaphthalenesulfonate 1% calcium/magnesium bentonite 59%

The ingredients are blended, hammer-milled and then moistened with about 12% water. The mixture is extruded as cylinders about 3 mm diameter which are cut to produce pellets about 3 mm long. These may be used directly af er drying, or the dried pellets may be crushed to pass a U.S.S. No. 20 sieve (0.84 mm openings). The granules held on a U.S.S. No. 40 sieve (0.42 mm openings) may be packaged for use and the fines recycled. Example 19

Low Strength Granule

2-Propyl-N-[ (4,6-dimethoxy-pyrimidin-2-yl)amino- carbonyl]-2,3-dihydro-5-methyl-1.2-benziso- thiazole-7-sulfonamide, S.S-dioxide 0.1% attapulgite granules 99.9%

(U.S.S. 20-40 mesh) The active ingredient is dissolved in a solvent and the solution is sprayed upon dedusted granules in a double-cone blender. After spraying of the solution has been completed, the material is warmed to evapor¬ ate the solvent. The material is allowed to cool and then packaged.

Example 20 Granule 2-Butyl-N-[ (4,6-dimethoxypyrimidin-2-yl)amino- carbonyl]-2.3-dihydro-5-methoxy-l.2-benziso- thiazole-7-sulfonamide, S,S-dioxide 80% wetting agent 1% crude ligninsulfonate salt (containing 10% 5-20% of the natural sugars) attapulgite clay 9%

The ingredients are blended and milled to pass through a 100 mesh screen. This material is then added to a fluid bed granulator, the air flow is adjusted to gently fluidize the material, and a fine spray of water is sprayed onto the fluidized material. The fluidiza- tion and spraying are continued until granuleε of the desired size range are made. The spraying is stopped, but fluidization is continued, optionally with heat, until the water content is reduced to the deεired level, generally less than 1%. The material is then discharged, screened to the desired size range, gener¬ ally 14-100 mesh (1410-149 microns), and packaged for use. Example 21

Low Strength Granule

2-Propyl-N-[ (4.6-dimethoxy-pyrimidin-2-yl)amino- carbonyl]-2,3-dihydro-5-methy1-1,2-benziso- thiazole-7-sulfonamide. S,S-dioxide 1% N.N-dimethylformaraide 9% attapulgite granules 90%

(U.S.S. 20-40 sieve) The active ingredient is dissolved in the solvent and the solution is sprayed upon dedusted granules in a double cone blender. After spraying of the solution has been completed, the blender is allowed to run for a short period and then the granules are packaged.

Example 22 Aqueous Suspenεion 2-Butyl-N-[ (4,6-dimethoxypyrimidin-2-yl)amino- carbonyl]-2, 3-dihydro-5-methoxy-l.2-benziso- thiazole-7-sulfonamide, S.S-dioxide 40.0% polyacrylic acid thickener 0.3% dodecylphenol polyethylene glycol ether 0.5% disodium phosphate 1.0% monosodium phosphate 0.5% polyvinyl alcohol 1.0% water 56.7%

The ingredients are blended and ground together in a sand mill to produce particles essentially all under 5 microns in size. Example 23 Solution

2-Propyl-N-[(4.6-dimethoxy-pyrimidin-2-yl)amino- carbony1]-2,3-dihydro-5-methyl-l,2-benziso- thiazole-7-sulfonamide. S.S-dioxide 5% water 95%

The salt is added directly to the water with stirring to produce the solution, which may then be packaged for use. Example 24

High Strength Concentrate

2-Butyl-N-[(4.6-dimethoxypyrimidin-2-yl)amino- carbonyl]-2.3-dihydro-5-methoxy-l,2-benziso- thiazole-7-sulfonamide. S.S-dioxide 99.0% silica aerogel 0.5% synthetic amorphous silica 0.5%

The ingredients are blended and ground in a hammer-mill to produce a material essentially all passing a U.S.S. No. 50 screen (0.3 mm opening). The concentrate may be formulated further if necessary.

Example 25 Wettable Powder

2-Propyl-N-[ (4.6-dimethoxy-pyrimidin-2-yl)amino- carbonyl]-2, 3-dihydro-5-methyl-l.2-benziso- thiazole-7-sulfonamide, S.S-dioxide 90.0% dioctyl sodium sulfosuccinate 0.1% synthetic fine silica 9.9%

The ingredients are blended and ground in a hammer-mill to produce particles essentially all below loo microns. The material is sifted through a U.S.S. No. 50 screen and then packaged. Example 26 Oil Suspension

2-Butyl-N-[ (4,6-dimethoxypyrimidin-2-yl)amino- carbonyl]-2,3-dihydro-5-methoxy-l,2-benziso- thiazole-7-sulfonamide, S,S-dioxide 35% blend of polyalcohol σarboxylic- 6% esters and oil soluble petroleum sulfonates xylene 59% The ingredients are combined and ground together in a sand mill to produce particles essentially all below 5 microns. The product can be used directly, extended with oils, or emulsified in water.

Example 27 Dust

2-Propyl-N-[ (4,6-dimethoxy-pyrimidin-2-yl)amino- carbon 1]-2,3-dihydro-5-methy1-1.2-benziso- thiazole-7-sulfonamide, S,S-dioxide 10% attapulgite 10% Pyrophyllite 80%

The active ingredient is blended with attapul¬ gite and then passed through a hammer-mill to produce particles substantially all below 200 microns. The ground concentrate is then blended with powdered pyro- phyllite until homogeneous.

Example 28 Oil Suspension

2-Butyl-N-[ (4.6-dimethoxypyrimidin-2-yl)araino- carbonyl]-2,3-dihydro-5-methoxy-l,2-benziso- thiazole-7-sulfonamide, S,S-dioxide 25% polyoxyethylene sorbitol hexaoleate 5% highly aliphatic hydrocarbon oil 70%

The ingredients are ground together in a sand mill until the solid particles have been reduced to under about 5 microns. The resulting thick suspension may be applied directly, but preferably after being extended with oils or emulsified in water.

Example 29 Wettable Powder 2-Propyl-N-C(4.6-dimethoxy-pyrimidin-2-yl)amino- carbonyl]-2.3-dihydro-5-meth 1-1,2-benziso- thiazole-7-sulfonamide, S,S-dioxide 20% sodium alkylnaphthalenesulfonate 4% sodium ligninsulfonate 4% low viscosity methyl cellulose 3% attapulgite 69%

The ingredients are thoroughly blended. After grinding in a hammer-mill to produce particles essen¬ tially all below 100 microns, the material is reblended and sifted through a U.S.S. No. 50 sieve (0.3 mm opening) and packaged.

UTIL ITY

The compounds of this invention are particularly useful for the control of weeds in sugar beets and fodder beets. This is a crop that takes a long period to become established. In this interval, the crop seedlings must be nurtured carefully, with particular attention to weed control to prevent damage due to competition. The subject compounds can be used either pre- or postemergence and will control numerous problem weeds including galium (Galium aparine) . pigweed (Amaranthus spp.). larabsquarter (Chenopodium album) . wild oats (Avena fatua) , wild radish (Raphanus raphanistrum) , and blackgrass (Alopecurus myosuroides) .

The rate of application for these compounds is determined by a number of factors including the weeds to be controlled, weather and climate, soil type, time of application, age and size of crop and weeds, method_^ of application (pre or post), etc. In general terms, the rate will vary between about 25 and 250 g/ha. The rate to be used in any given situation can be selected by one with ordinary skill in the art.

These compounds can and will often be used in mixtures with one or more other herbicides. They may be mixed with any other herbicide selective on beets including metaraitron, phenmedipham, chloridazin, desmedipham, lenacil, ethofumesate. cycloate, diclofop-methyl, fuazifop, haloxyfop and Aεsure®.

The selective properties of these compounds were discovered in greenhouse tests. The results of these tests are shown in the tables below. Test A Postemergence

Two round pans (25 cm diameter by 12.5 cm deep) were filled with Sassafras sandy loam soil. One pan was planted with blaσkgrass (Alopecurus myosuroides) , sugar beets, nutsedge (Cyperus rotundus) tubers, rape (Brassica napus) , crabgrass {Digitaria sanguinalis) , sicklepod (Cassia obtusifolia') . teaweed (Sida spinosa) . jimsonweed (Datura stramonium), velvetleaf (Abutilon theophrasti) . and giant foxtail (Setaria faberii) . The other pan was planted with wheat, cotton, rice, corn, soybean, wild oats (Avena fatua) , cocklebur (Xanthium pensylvanicum) . morningglory (Ipomoea hederacea). johnsongrass (Sorghum halepenεe) and barn- yardgrass (Echinochloa crusgalli) . The plants were grown for approximately fourteen days, then sprayed postemergence with Compound I or Compound II dissolved in a non- phytotoxic solvent. ,

Preemergence TWO round pans (25 cm diameter by 12.5 cm deep) were filled with Sasεafraε sandy loam soil. One pan was planted with blackgrass, sugar beets, nutsedge, rape, crabgrass. sicklepod. teaweed, jimsonweed. velvetleaf, and giant foxtail. The other pan was planted with wheat, cotton, rice, corn, soybeans, wild oats, cocklebur. morningglory, johnsongrass and barn- yardgrass. The two pans were sprayed preemergence with Compound I or Compound II disεolved in a non-phytotoxic εolvent. Treated plants and controls were maintained in the greenhouse for 28 days, then all treated plants were compared to controls and visually rated for plant response.

Response ratings are based on a scale of 0 to loo where 0 = no effect, and 100 = complete control. A dash (-) response means no test.

The results are summarized in Table 2. Table 2

Compound I

Rate (g/ha) 16 62

POSTEMERGENCE

Nutsedge 0 0 0 Crabgrass 0 20 50

Cassia 40 80 90

Teaweed 20 50 80

Rape 80 100 100

Jimsonweed 60 90 90 velvetleaf 80 90 100

Blackgrass 30 80 100

Rice 50 60 100

Sugar Beets 0 20 20

Wheat- 0 60 80 wild Oats 0 20 80

Cocklebur 0 40 80

Morningglory 40 80 90

Cotton 30 90 100

Johnsongrass 70 80 100 Barnyardgrass 0 30 40

Giant Foxtail 40 80 80

Soybeans 80 100 100

Corn 80 100 100

Table 2 (Cont'd)

Compound I

Rate (g/ha) 62 250

PREEMERGENCE

Nutsedge 0 0 Crabgrass 30 80

Cassia 0 50

Teaweed 0 60

Rape 20 70

Jimsonweed 0 60 Velvetleaf 60 80

Blackgrass 70 80

Rice 50 90

Sugar Beets 0 0

Wheat 0 20 wild Oats 60 80

Cocklebur 0 0

Morningglory 0 40

Cotton 0 20

Johnεongraεs 80 90 Barnyardgrass 30 80

Giant Foxtail 70 90

Soybeans 20 80

Corn 0 40

Table 2 (Cont'd) -

Compound II

Rate (g/ha) 16 62

POSTEMERGENCE

Nutsedge 60 90 100 Crabgrass 60 100 100

Cassia 70 80 100

Teaweed 20 60 90

Rape 100 100 100

Jimsonweed 50 70 100 Velvetleaf 60 90 100

Blackgrass 90 100 100

Rice 100 100 100

Sugar Beets 30 "50 100

Wheat 20 90 100 wild Oats 60 100 100

Cocklebur 20 40 70

Morningglory 0 20 90

Cotton 0 20 90

Johnsongrass 100 100 100 Barnyardgrass 90 100 100

Giant Foxtail 100 100 100

Soybeans 40 100 100

Corn 100 100 100

Table 2 (Cont'd)

Compound II

Rate (g/ha) 16 62 250

PREEMERGENCE

Nutsedge 0 0 80 Crabgrass 70 90 100

Cassia 0 0 50

Teaweed 40 70 90

Rape 0 20 100

Jimsonweed 20 50 100 Velvetleaf 30 70 100

Blackgrass 90 90 100

Rice 80 90 100

Sugar Beets 0 , 20 60

Wheat 70 100 100 wild Oats 70 100 100

Cocklebur 0 20 80

Morningglory 30 30 60

Cotton 0 20 40

Johnsongrass 80 90 100 Barnyardgrass 90 90 100

Giant Foxtail 90 100 100

Soybeans 0 20 80

Corn 0 80 100

Test B Seeds of the following crops and weeds are sown into 15 cm diameter pots containing Sassafras sandy loam soil: wheat (Triticum aestivum) , barley (Hordeum vulgare) . sugar beet (Beta vulgaris), black nightshade (Solanu nigrura). chickweed (Stellaria media) . common lambsquarters (Chenopodium album), Galium (Galium aparine) . knotweed (Poiygonum avicularβ). Kochia (Kochia scoparia) , Matricaria (Matricaria inodora) . redroot pigweed (Amaranthus retroflexus) , smartweed (Poiygonum persicaria) , speedwell (Veronica persica) , wild buckwheat (Poiygonum convolvulus) . wild mustard (Brassica kaber) , wild radish (Raphanus raphanistru ) . annual bluegrass (Poa annua) , annual ryegrass (Lolium multiflorum) . blackgrass (Alopecurus myosuroides) . green foxtail (Setaria viridis) . and wild oats (Avena fatua) . Compound I or Compound II was formulated in a non-phytotoxic solvent and applied to the plants as a foliar spray. Plantε are treated at three εtages: 1) preemergence, 2) postemergence when sugar beets are at the 1st true leaf stage, and 3) postemergence when sugar beets have three leaves. Plants are grown in a temperature- controlled greenhouse for the duration of the experiment. Weed control and crop injury are evaluated visually (3 to 4 weeks following compound application), using a scale of 0 to 100%, where 0 = no injury or control and 100 = complete death of the plants. The ratings represent averages of two tests run under identical conditions and are summarized in Table 3. Table 3

Compound I

Leaf Stage 1st 3rd 1st 3rd 1st 3rd 1st 3rd

Rate (g/ha) 16 16 3J) 30 6_3 1 125 125

POSTEMERGENCE

wheat 42 48 62 48 62 68 92 100

Barley 58 90 95 95 100 98 98 100

Sugar Beets 0 O 0 0 0 0 12 12

Black Nightshade 0 0 12 0 85 0 15 25

Chickweed 45 55 98 95 100 98 100 100 Lambsguarters 68 70 98 95 100 85 100 78

Galium 38 20 98 92 92 90 100 88

Knotweed 25 20 62 0 62 0 60 25

Kochia 0 - 0 - 12 - 95 -'

Matricaria 0 0 0 0 ^' 30 30 32 20 pigweed 95 95 100 100 98 98 98 100

Smartweed 28 45 62 60 68 62 80 75

Speedwell 42 0 10 15 52 20 42 12

Buckwheat 0 48 0 0 100 0 60 20

Mustard 98 90 98 95 100 98 100 98 wild Radish 92 95 95 100 100 98 100 98

Bluegrass 0 10 62 35 85 72 75 85

Ryegrass 0 0 0 10 10 20 35 50

Blackgrasε 18 12 12 45 80 85 92 98

Green Foxtail 22 45 58 88 90 88 98 98 wild Oats 18 68 95 88 100 100 100 98 Table 3 (Cont'd)

Compound I

Rate (g/ha) ϋ I_, 6_3_ 125

PREEMERGENCE

Wheat 0 0 22 40 Barley O 0 35 55

Sugar Beets 0 0 0 0

Black Nightshade 32 20 50 70

Chickweed 0 0 50 70

Lambsquarters 38 62 70 88 Galium 0 50 85 98

Knotweed 0 0 0 15

Kochia 0 95 20 0

Matricaria 25 55 90 95

Pigweed 12 10 60 98 Smartweed 20 28 45 62

Speedwell 0 45 50 35

Buckwheat 0 45 90 38

Mustard 20 85 98 98

Wild Radish 62 72 98 98 Bluegrasε 0 12 38 55

Ryegraεε 0 0 10 0

Blackgrass 0 20 42 65

Green Foxtail 0 0 48 62

Wild Oats 0 10 60 78 Table 3 (Cont ' d )

Compound II

Leaf Stage 1st 3rd 1st 3rd 1st 3rd 1st 3rd

Rate (g/ha) 16 1£ 30 . 63 11 125 125

POSTEMERGENCE

Wheat 60 70 85 85 95 85 100 100

Barley 80 90 95 100 95 95 100 100

Sugar Beets 0 20 30 30 40 45 40 45

Black Nightshade O 25 75 35 95 75 85 100

Chickweed 60 90 100 95 95 90 95 100 Lambsguarters 75 75 90 75 95 95 95 100

Galium 90 95 100 95 100 100 100 100

Knotweed 20 25 25 35 40 25 40 30

Kochia _t 80 85 75 0 100 100 100 100

Matricaria 0 0 50 0 50 35 100 50 Pigweed 85 85 100 90 100 90 95 95

Smartweed 25 40 90 40 90 90 80 95

Speedwell 0 0 0 0 0 0 25 40

Buckwheat 0 0 25 75 85 85 95 95

Mustard 90 95 100 100 100 95 100 100 wild Radish 95 95 100 100 100 100 100 95

Bluegrass 100 100 100 100 100 100 100 100

Ryegrass 100 100 100 100 100 100 100 100

Blackgrass 100 100 100 100 100 100 100 100

Green Foxtail 100 95 100 100 100 100 100 100 wild Oatε 100 100 100 100 100 100 100 ^' 100 Table 3 (Cont'd)

Compound II

Rate (g/ha) 16 30 63 r 125

PREEMERGENCE

Wheat 45 75 85 85 Barley 40 85 85 90

Sugar Beets 0 25 40 35

Black Nightshade 0 25 35 50

Chickweed 0 70 100 90

Larabsquarters 60 75 75 85 Galium 0 50 100 100

Kno weed 0 0 60 60

Kochia 0 0 65 65

Matricaria 40 70 95 95

Pigweed 40 95 85 90 smartweed 20 40 25 40

Speedwell 0 25 0 25

Buckwheat 0 0 70 65

Mustard 80 100 100 95

Wild Radish 75 100 95 100 Bluegrasε 60 95 95 90

Ryegraεε 95 100 95 95

Blaσkgraεε 95 100 95 100

Green Foxtail 50 95 95 100

Wild Oats 50 90 90 90

Claims

WHAT IS CLAIMED IS:

1. A compound which is 2-butyl-N-[ (4.6- dimethoxypyrimidin-2-yl)-aminocarbonyl]-2.3- dihydro-5-methoxy-1.2-benzisothiazole-7-sulfon- amide. S.S-dioxide.

2. A compound which is 2-propyl-N-[ (4.6- dimethoxypyrimidin-2-yl)-aminocarbonyl]-2.3- dihydro-5-methyl-l,2-benzisothiazore-7-sulfonamide- S.S-dioxide.

3. A composition suitable for controlling the growth of undesired vegetation which comprises an effective amount of the compound of Claim 1 and at least one of the following: surfactant, solid or liquid diluent.

4. A composition suitable for controlling the growth of undesired vegetation which comprises an effective amount of the compound of Claim 2 and at least one of the following: surfaσtant. solid or liquid diluent.

5. A method for controlling the growth of undesired vegetation which comprises applying to the locus to be protected an effective amount of the com¬ pound of Claim 1.

6. A method for controlling the growth of undesired vegetation which comprises applying to the locus to be protected an effective amount of the com¬ pound of Claim 2.

7. A method of Claim 5 wherein the locus to be protected is a sugar beet crop.

8. A method of Claim 6 wherein the locus to be protected is a sugar beet crop.