Methods for producing sulfonic acid diamides

Abstract

The present invention relates to a process for preparing sulfuric diamides of the general formula I
R.sup.1R.sup.2NS(O).sub.2NH.sub.2(I)
in which R.sup.1 and R.sup.2 are each independently a primary alkyl radical having from 1 to 8 carbon atoms, a secondary alkyl radical having from 3 to 8 carbon atoms or a cycloalkyl radical having from 5 to 8 carbon atoms, or, together with the nitrogen atom, form a 5- to 8-membered, saturated nitrogen heterocycle which, as well as the nitrogen atom, may have a further heteroatom selected from O and S as a ring member, where the nitrogen heterocycle is unsubstituted or may have 1, 2, 3 or 4 alkyl groups having in each case from 1 to 4 carbon atoms as substituents. The process comprises the following steps: i) the reaction of a secondary amine of the formula II
R.sup.1R.sup.2NH(II) in which R.sup.1 and R.sup.2 are each as defined above with sulfuryl chloride in an inert solvent, especially an aromatic solvent, in the presence of a tertiary amine to give a sulfamoyl chloride of the formula III
R.sup.1R.sup.2NS(O).sub.2Cl(III) in which R.sup.1 and R.sup.2 are each as defined above, and ii) reaction of the sulfamoyl chloride of the formula III obtained in step i) with ammonia,
the sulfamoyl chloride of the formula III being used in step ii) in the form of the solution obtained in step i) in the inert solvent, especially the aromatic solvent.

Claims

1. A process for preparing a sulfuric diamide of the formula (I)
R.sup.1R.sup.2NS(O).sub.2NH.sub.2(I) in which R.sup.1 and R.sup.2 are each independently a primary alkyl radical having from 1 to 8 carbon atoms, a secondary alkyl radical having from 3 to 8 carbon atoms or a cycloalkyl radical having from 5 to 8 carbon atoms, comprising i) reacting a secondary amine of the formula (II)
R.sup.1R.sup.2NH(II) with sulfuryl chloride in an inert organic solvent in the presence of a tertiary amine to give a sulfamoyl chloride of the formula (III)
R.sup.1R.sup.2NS(O).sub.2Cl(III) wherein the tertiary amine is present in amount of from 1.05 to 1.5 equivalents, based on the secondary amine of formula (II); and wherein the secondary amine of the formula (II) and sulfuryl chloride are used in a molar ratio of from 1:1.1 to 1.1:1; and ii) reacting the sulfamoyl chloride of the formula (III) obtained in step i) with gaseous ammonia, wherein the reaction is performed at temperatures in the range of from 30 to 80 C., the sulfamoyl chloride of the formula (III) being used in step ii) in the form of the solution obtained in step i) in the inert organic solvent.

2. The process according to claim 1, wherein step i) comprises an extractive removal of the salts formed in the reaction.

3. The process according to claim 1, wherein the tertiary amine is a tri-C.sub.1-C.sub.6-alkylamine.

4. The process according to claim 1, wherein the R.sup.1 radical in the formulae (I), (II) and (III) is a primary alkyl radical having from 1 to 8 carbon atoms or a secondary alkyl radical having from 3 to 8 carbon atoms and the R.sup.2 radical is a secondary alkyl radical having from 3 to 8 carbon atoms.

5. The process according to claim 4, wherein the secondary amine of the formula (II) is N-(1-methylethyl)-N-methylamine.

6. The process according to claim 1, wherein the inert organic solvent is an aromatic solvent.

7. The process according to claim 6, wherein the aromatic solvent comprises chlorobenzene.

8. A process for preparing active herbicidal ingredients of the general formula (IV) ##STR00007## in which R.sup.1 and R.sup.2 are each as defined in claim 1, R.sup.a is hydrogen or C.sub.1-C.sub.4-alkyl, R.sup.b is hydrogen, C.sub.1-C.sub.4-alkyl or C.sub.1-C.sub.4-haloalkyl, X and Y are each hydrogen or halogen, where one of the X or Y radicals may also be CN, comprising a) preparing the sulfuric diamide of the formula I by the process according to claim 1, b) reacting the sulfuric diamide of the formula (I) with a 3-nitrobenzoyl chloride of the formula (V) to obtain a 3-nitrobenzenesulfonamide of the formula (VI); ##STR00008## c) reducing the 3-nitrobenzenesulfonamide of the formula (VI) to a 3-aminobenzenesulfonamide of the formula (VII) ##STR00009## d) converting the 3-aminobenzenesulfonamide of the formula (VII) to a compound of the formula (IV).

9. The process according to claim 8, wherein step d) comprises: d1) reacting the 3-aminobenzenesulfonamide of the formula (VII) with a C.sub.1-C.sub.4-alkyl chloroformate to give a compound of the formula (VIII) ##STR00010## in which R.sup.1, R.sup.2, X and Y are each as defined for formula (IV) and R.sup.3 is C.sub.1-C.sub.4-alkyl, d2) reacting the compound (VIII) with a 3-aminoacrylic ester of the formula (IX) ##STR00011## in which R.sup.a is hydrogen or C.sub.1-C.sub.4-alkyl, R.sup.b is hydrogen, C.sub.1-C.sub.4-alkyl or C.sub.1-C.sub.4-haloalkyl and R.sup.4 is C.sub.1-C.sub.4-alkyl, and d3) when R.sup.a is hydrogen, optional alkylation of the compound IV obtained in step d2), in which R.sup.a is hydrogen, with a compound R.sup.aa-L in which R.sup.aa is C.sub.1-C.sub.4-alkyl and L is a nucleophilically displaceable leaving group, to obtain a compound of the general formula (IV).

Description

EXAMPLE 1

Preparation of N-methyl-N-(1-methylethyl)aminosulfonamide (Compound I where R1=methyl, R2=1-methylethyl)

Step a)

(1) A reaction vessel was initially charged under inert gas atmosphere with 137.7 g (1.0 mol) of sulfuryl chloride in 800 g of chlorobenzene and cooled to internal temperature 5 C. To this were added, over a period of 300 minutes, a mixture of 73.1 g (1.0 mol) of isopropylmethylamine and 116.3 g (1.15 mol) of triethylamine, in the course of which the temperature was kept within the range from 0 to 5 C. by cooling. After the addition had ended, the resulting suspension was stirred at 10 C. for a further 120 minutes. The suspension was then added to 250 g of 10% hydrochloric acid at 10 C. The phases were separated at 10 C. and the organic phase was washed again with 250 g of 10% aqueous hydrochloric acid at 10 C. The organic phase was removed and concentrated under reduced pressure (30 mbar, 22 to 41 C.), in order to remove water. In this way, 570 g of a solution of N-isopropyl-N-methylsulfamoyl chloride in chlorobenzene (about 25% by weight) were obtained. This corresponds to a yield of 84%.

(2) 343.4 g of the solution of N-isopropyl-N-methylsulfamoyl chloride in chlorobenzene (25% strength by weight) obtained in step i) were introduced into a pressure vessel which was flushed with nitrogen and ammonia. Subsequently, the partial pressure of the ammonia was increased to 5 bar. The reactor contents were then heated to 50 C., and this temperature was maintained for 8 hours, in the course of which an ammonia pressure of 6 bar was maintained. The suspension obtained here was added to 210 g of aqueous hydrochloric acid (8% strength), which dissolved the solids present in the reaction mixture. The pH of the aqueous phase was about 2. The phases were separated at 40 C. and the aqueous phase was extracted twice with 372 g of chlorobenzene each time. In this way, 1065 g of a 6.3% by weight solution of the title compound in chlorobenzene was obtained, which corresponds to a yield of 88%. The solution can be used directly in the subsequent reaction.

EXAMPLE 2

Preparation of 2-chloro-5-[3,6-dihydro-3-methyl-2,6-dioxo-4-(trifluoromethyl)-1-(2H)-pyrimidinyl]-4-fluoro-N-[[methyl-(1-methylethyl)amino]sulfonyl]-benzamide

Step b): (2-chloro-4-fluoro-5-nitrobenzoyl)-N-isopropyl-N-methylsulfamide

(3) To a solution of 43.1 g (0.277 mol) of N-methyl-N-(1-methylethyl)sulfamoylamide and 0.77 g (12.0 mmol) of tributylmethylammonium chloride in 637 g of chlorobenzene were added, at 20 C. within 60 min, 43.7 g (50% strength in water) of NaOH. 15 minutes after the start of addition of the base, 65.0 g (0.26 mol) of 2-chloro-4-fluoro-3-nitrobenzoyl chloride in 70 g of chlorobenzene were added within 45 min. Both metered additions ended simultaneously. The reaction mixture was subsequently stirred at 20 C. for 1 h and diluted by means of addition of 424 g of water and 138 g of isohexane. The aqueous phase was acidified to pH 4.5 with concentrated hydrochloric acid and then removed at 68-70 C. The organic phase was admixed with 430 g of water and 60 g of isohexane and the phases were separated again at pH 4.5 while hot. The resulting organic phase was admixed with a further 280 g of isohexane and then cooled to 5 C. After filtration, washing with water and drying at 70 C. under reduced pressure, 82.1 g (87% of theory, purity 97%) of N-(2-chloro-4-fluoro-5-nitrobenzoyl)-N-isopropyl-N-methylsulfamide were obtained.

(4) .sup.1H NMR (400 MHz, CDCl.sub.3) =9.1 ppm (s, NH), 8.4 (d, ArH), 7.45 (d, ArH), 4.25 (sept., iso-Pr-H), 2.95 (s, Me), 1.25 (d, iso-Pr-H). iso-Pr=isopropyl=1-methylethyl

Step c): N-(2-chloro-4-fluoro-5-aminobenzoyl)-N-isopropyl-N-methylsulfamide

(5) 177 g (0.500 mol; 99.9%) of N-(2-chloro-4-fluoro-3-nitrobenzoyl)-N-isopropyl-N-methylsulfamide were admixed in 397 g of methanol with 2.17 g (0.008 mol %) of 1% Pt/C (63% suspension in water). The mixture was hydrogenated with 5 bar of hydrogen at 60-70 C. with stirring. After 2 h, the solution was decompressed, the reaction mixture was filtered at 60 C. and the solvent was removed by distillation. 157.8 g (97.5% of theory, purity: 99%) of N-(2-chloro-4-fluoro-5-aminobenzoyl)-N-isopropyl-N-methylsulfamide were obtained as a white-yellowish solid (m.p.: 147-149 C.).

(6) .sup.1H NMR (400 MHz, d-DMSO) =11.9 ppm (s, NH), 7.35 (d, ArH), 6.90 (d, ArH), 5.50 (br. s., NH.sub.2), 4.05 (sept., iso-Pr-H), 2.80 (s, Me), 1.15 (d, iso-Pr-H).

Step d1): N-[2-chloro-4-fluoro-5-{(ethoxycarbonyl)amino}benzoyl]-N-isopropyl-N-methylsulfamide (Variant 1)

(7) To a solution of 50.0 g (0.153 mol; 99.3%) of N-(2-chloro-4-fluoro-5-aminobenzoyl)-N-isopropyl-N-methylsulfamide in 225 g of toluene were added, at 105-110 C., 22.7 g (0.207 mol) of ethyl chloroformate and the mixture was subsequently stirred at 108-110 C. for 6.5 h. The reaction mixture was concentrated to dryness on a rotary evaporator under reduced pressure. After drying under reduced pressure at 70 C., 59.9 g (98.4% of theory, purity 99.7%) of N-[2-chloro-4-fluoro-5-{(ethoxycarbonyl)-amino}benzoyl]-N-isopropyl-N-methylsulfamide were obtained.

(8) .sup.1H NMR (400 MHz, CDCl.sub.3) =8.9 ppm (s, NH), 8.4 (d, ArH), 7.2 (d, ArH), 6.80 (s, NH), 4.30-4.20 (m, iso-Pr-H, CH.sub.2O), 2.95 (s, Me), 1.40 (q, CH.sub.3CH.sub.2O), 1.25 (d, iso-Pr-H).

Step d1): N-[2-chloro-4-fluoro-5-{(ethoxycarbonyl)amino}benzoyl]-N-isopropyl-N-methylsulfamide (Variant 2)

(9) To a solution of 50.0 g (0.153 mol; 99.3%) of N-(2-chloro-4-fluoro-5-aminobenzoyl)-N-isopropyl-N-methylsulfamide in 450 g of toluene were added, at 105-110 C., 26.9 g (0.245 mol) of ethyl chloroformate and the mixture was then stirred at 108-110 C. for 6.5 h. The reaction mixture was concentrated to dryness on a rotary evaporator under reduced pressure. After drying under reduced pressure at 70 C., 61.2 g (99.3% of theory, purity 98.4%) of N-[2-chloro-4-fluoro-5-{(ethoxycarbonyl)amino}benzoyl]-N-isopropyl-N-methylsulfamide were obtained.

Step d2): 2-chloro-5-[3,6-dihydro-2,6-dioxo-4-(trifluoromethyl)-1(2H)-pyrimidinyl]-4-fluoro-N-{[methyl-(1-methylethyl)amino]sulfonyl}benzamide

(10) 396 g (1 mol) of N-(2-chloro-4-fluoro-5-[(ethoxycarbonyl)amino]benzoyl)-N-isopropyl-N-methylsulfamide were dissolved at room temperature in 1583 g of DMF (=dimethylformamide), and 189 g (1.02 mol) of ethyl 3-amino-4,4,4-trifluoro-2-butenoate were added. 378 g (2.1 mol) of sodium methoxide solution (30% in methanol) were metered in at 115-120 C. within 4 h, and methanol and ethanol were distilled off during this time. The mixture was left to stir for a further 30 min. For workup, the reaction mixture was metered with cooling into dilute sulfuric acid, and, after the end of the addition, the reaction mixture had a pH of <2 and the title compound precipitated out as a solid. The precipitated product was filtered off, washed with water and dried. 433 g (89% of theory) of the title compound were obtained [m.p. 238 C. (decomposition)].

Step d3): 2-chloro-5-[3,6-dihydro-3-methyl-2,6-dioxo-4-(trifluoromethyl)-1-(2H)-pyrimidinyl]-4-fluoro-N-[[methyl-(1-methylethyl)amino]sulfonyl]benzamide

(11) 40.0 g (0.0785 mol) of 2-chloro-5-[3,6-dihydro-2,6-dioxo-4-(trifluoromethyl)-1(2H)-pyrimidinyl]-4-fluoro-N-{[methyl-(1-methylethyl)amino]sulfonyl}benzamide, 2.5 g (0.0078 mol) of tetrabutylammonium bromide (=TBAB) and 13.4 g (0.106 mol) of dimethyl sulfate were initially charged at 25 C. in a mixture of toluene, water and THF (=tetrahydrofuran), and the mixture was heated to 40 C. Subsequently, by adding aqueous 10% NaOH solution, a pH of 5.3-5.5 was established in the reaction mixture. The mixture was stirred at 40 C. for 1 h, in the course of which 10% aqueous NaOH solution continued to be added, such that the pH was constant at the pH established beforehand. After 1 h, the addition of the aqueous 10% NaOH solution was stopped, whereupon the pH fell to 4.4-4.5. The mixture was left to stir at a pH of 4.4-4.5 and 40 C. for a further 5.5 h. After the reaction had ended, the phases were separated, the organic phase was dried and the solvent was partly removed. In the course of cooling, the title compound crystallizes out, and is filtered off, washed with toluene and dried (33 g, 84%).

EXAMPLE 3

Preparation of 2-chloro-5-[3,6-dihydro-3-methyl-2,6-dioxo-4-(trifluoromethyl)-1-(2H)-pyrimidinyl]-4-fluoro-N-[[methyl-(1-methylethyl)amino]sulfonyl]-benzamide (Variant with Performance of Steps c) and d1) without Intermediate Isolation)

(12) The preparation was effected analogously to the method for example 2, with the difference that steps c) and d1) were carried out as follows:

(13) 179 g (0.500 mol; 99%) of N-(2-chloro-4-fluoro-3-nitrobenzoyl)-N-isopropyl-N-methylsulfamide were admixed in 391 g of methanol with 4.08 g (0.015 mol %) of 1% Pt/C (63% water) and hydrogenated with 5 bar of hydrogen at 60-70 C. with stirring. After 2 h, the solution was decompressed, the reaction mixture was filtered at 60 C. and the solution was admixed with 2200 g of toluene. The methanol was removed by distillation together with the water of reaction at 65-68 C. while gradually lowering the pressure from 900 mbar to 250 mbar. Subsequently, the suspension of N-(2-chloro-4-fluoro-5-aminobenzoyl)-N-isopropyl-N-methylsulfamide in toluene was heated to 106-107 C. and admixed with 64.4 g (0.588 mol) of ethyl chloroformate within 10 min. The mixture was subsequently stirred at 110 C. for 6.5 h. Subsequently, 746 g of toluene were distilled off at standard pressure and the mixture was then cooled to internal temperature 5 C. After the product solution had been seeded with 150 mg of the target compound, the product crystallized at 5 C. within 60 min. After filtration and drying under reduced pressure at 70 C., 166.2 g (95.0% of theory, purity 98.5%) of N-[2-chloro-4-fluoro-5-{(ethoxycarbonyl)amino}benzoyl]amino}benzoyl]-N-isopropyl-N-methylsulfamide were obtained.

EXAMPLE 4

Preparation of 2-chloro-5-[3,6-dihydro-3-methyl-2,6-dioxo-4-(trifluoromethyl)-1-(2H)-pyrimidinyl]-4-fluoro-N-[[methyl-(1-methylethyl)amino]sulfonyl]-benzamide (Variant with Crystallization of the Product Obtained in d1))

(14) The preparation was effected analogously to the method for example 2, with the difference that step d1) was carried out as follows:

(15) To a solution of 150.9 g (0.466 mol) of N-(2-chloro-4-fluoro-5-aminobenzoyl)-N-isopropyl-N-methylsulfamide in 350 g of methanol and 18.4 g of water were added 1100 g of toluene. The methanol was removed by distillation together with the water at 65-68 C. while gradually lowering the pressure from 900 mbar to 250 mbar. Subsequently, the suspension of N-(2-chloro-4-fluoro-5-aminobenzoyl)-N-isopropyl-N-methylsulfamide in toluene was heated to 108-109 C., then admixed with 64.4 g (0.588 mol) of ethyl chloroformate within 10 min and subsequently stirred at 110 C. for 6.5 h. After the product solution had been seeded with 100 mg of the target compound, the product crystallized at 5 C. within 60 min. After filtration and drying at 70 C. under reduced pressure, 169.6 g (92.0% of theory, purity 99.7%) of N-[2-chloro-4-fluoro-5-{(ethoxycarbonyl)amino}benzoyl]amino}benzoyl]-N-isopropyl-N-methylsulfamide were obtained.