DD251342A1 - METHOD FOR THE PRODUCTION OF TRISUBSTITUTED N-METHYL-ARENSULFONAMIDES TRISUBSTITUTED IN THE METHYL GROUP - Google Patents

Abstract

The invention relates to a process for the preparation of trisubstituted on the methyl group N-methyl-arensulfonamiden, which are obtained by reacting Arensulfonyl-iminokohlensaeurehalogeniden with Grignard compounds. The aim of the invention is to find an uncomplicated to be realized process for the preparation of the title compounds, the u. a. as intermediates for the production of pesticides and pesticides as well as pharmaceuticals may have meaning.

Description

or toluene, with the Arensulfonyl-iminokohlensäurehalogenids of the general formula II in one of the abovementioned solvents at temperatures between 0 ⁰ C and the boiling temperature of the solvent used in each case with the exclusion of moisture and air.

The N-methyl-arensulfonamide of the general formula I are obtained after customary hydrolytic workup of the reaction mixture in an acidic medium as a colorless, crystalline compound. The advantage of the invention is that N-methyl-arensulfonamides of the general formula I can be obtained by using the readily available arenesulfonyliminocarboxylic acid halides of the general formula II (Anders, B, Khle, E .: Angew Chem 77 [1965] 430 / Neidlein, R Haussmann, W. Heukelbach, E .: Chem. Ber. 99 [1966] 1252 / Kühle, E., Anders, B. Klauke, E., Thronow, H., Zumach, G .: Angew Chem. 81 [1969] 18 / Hans, M .; Dehne, H .; Hartwig R: Z. Chem. 26 [1986] in press) and Grignard compounds of general formula III can be prepared in a straightforward manner.

embodiment

The invention will be explained in more detail with reference to the following example and the data of the table, without reference thereto

to be limited.

To 50 ml of a 0.60 molar (0.03 mol) ethereal solution of benzylmagnesium chloride under argon atmosphere and stirring at room temperature 0.01 mol (2.64 g) of p-toluenesulfonyl-iminothiokohlensäuremethylester-chloride, dissolved in 30 ml of tetrahydrofuran, added dropwise slowly. The reaction can be observed on the discoloration and self-heating of the reaction solution.

First, it is stirred at room temperature and then heated for 1 hr. At reflux. After cooling, the reaction solution is slowly added to about 100 ml of 0.5 molar HCI-ice-water mixture. The organic solvents are i. Vak. distilled off, wherein the water-insoluble N-tribenzyl-methyl-p-toluenesulfonamide precipitated crystalline. After suction, the crude product is recrystallized from ethanol. This gives a crystalline, colorless substance of mp. 191-

Yield: 3.55 g (80% of theory)

Analytical data: C ₂₉ H ₂₉ NO ₂ S (455.63)

Calculated: C76.45 H 6.42 N 3.07 S 7.04

Found: C 76.12 H 6.38 N 3.19 S 7.08

IR / cm " ¹ /: v _{N. H} 3381; v _S o ₂ 1165.1321

Table 1: N-methyl-arensulfonamides I

Ser. Y. Schmp. From Il

No. R ¹ η R ² (%) ( ⁰ C) X

solvent

1 H O H 70 243-245 Cl SCW ₃ Ether / benzene 2 4-CH ₃ O H 60 239-242 Cl SCH ₃ Ether / benzene 3 4-CI O H 60 228-231 Cl SCH ₃ Ether / benzene 4 4-CH ₃ O 4-CI 15 209-212 Cl SCH ₃ THF 5 H 1 H 75 200-202 Cl SCH ₃ THF 6 4-CH ₃ 1 H 80 191-193 Cl SCH ₃ Ether / THF 7 4-CH ₃ 1 H 45 191-193 Cl Cl Ether / toluene 8th 4-CI 1 H 75 180-182 Cl SCH ₃ Ether / THF

X

Z-Mg- (CH ₂ ) _η - ~ -

Vr '

III

Claims (2)

1. A process for the preparation of N-methyl-arensulfonamides of the general formula I in which R ¹ and R ^{2 are} identical or different substituents located in identical or different positions, such as, for example, halogen atoms, alkyl, alkylthio or alkoxy groups with C ₁ - to C ₄ -GeKiSt or phenyl or phenoxy radicals, optionally also nitro groups, and η can take integer values between zero and two, characterized in that arenesulfonyl-iminocarbonic acid halide of the general formula H in whichX is a halogen atom and also Y is a halogen atom or an alkoxy radical or Alkylthiogruppierung with C ₁ - to C ₆ skeleton, a phenoxy or phenylthio radical, which may optionally be mono- or polysubstituted by identical or different substituents, for example by halogen atoms, alkyl, alkylthio or alkoxy with C ₁ - stands to C ₄ backbone and R ^{1 has} the meaning above with Grignar d compounds of general formula III in which R ² and η have the abovementioned meaning in a molar ratio of approximately 1: 3 in organic solvents, preferably in dialkyl ethers having 4 to 8 carbon atoms, cyclic ethers, such as 1,4-dioxane or tetrahydrofuran or in mixtures of the above solvents with aromatic hydrocarbons such as benzene or toluene at temperatures between ^{0 0} C and the boiling temperature of the particular solvent used. 2. The method according to item 1, characterized in that the reaction is carried out in the absence of moisture and air. 1 page_form_ _ Field of application of the invention The invention relates to a process for the preparation of trisubstituted on the methyl group N-methyl-arensulfonamiden, which are used as intermediates u. a. for the production of pesticides and pharmaceuticals. Characteristic of the known technical solutions Methods for the preparation of the inventively substituted N-methyl-arensulfonamide have not been described. N-alkyl (or N-aryl) substituted arenesulfonamides are known to be mainly from Arensulfonsäurechloriden and alkyl or arylamines or by alkylation or arylation of Arensulfonamiden or salts thereof. (Huntress, EH; Autenrieth, JS: J. Amer., 1987, 511; Huntress, EH; Carlen, F .: J. Amer., 1984, 34: 343; Muth, F.; - In: Methods of Organic Chemistry Bd.lX./Hrsg .: E.Müller .- Stuttgart: Georg Thieme Verlag, 1955. -S., 599-648). The abovementioned processes permit the production of the title compounds, if at all, only via unreasonably complex, multistep synthesis steps. Object of the invention The aim of the invention is to find a simple, versatile method for the preparation of the title compounds in high yields from readily available starting materials in a manner which can be easily implemented in a simple manner. Explanation of the essence of the invention The compounds which can be prepared by the process forming the subject of the invention are N-methyl-arenesulfonamides of the general formula I in which R ¹ and R ^{2 are} identical or different substituents, located in identical or different positions, such as, for example, halogen atoms, alkyl -, alkylthio or. Alkoxy groups with Ci-to C ^ skeleton or phenyl or. Phenoxy radicals, optionally also nitro groups and η can take integer values between zero and two. The N-methyl-arensulfonamides of general formula I according to the invention are prepared by reacting Arensulfonyliminokohlensäurehalogeniden of the general formula II in which X is a halogen atom and Y is also a halogen atom or an alkoxy or alkylthio with Cr to Ce skeleton, a phenoxy or phenylthio radical, which may optionally be monosubstituted or polysubstituted, identically or differently, in different positions, for example by halogen atoms, alkyl, alkylthio or alkoxy groups with CrisGt skeleton and R ^{1 has} the abovementioned meaning, with Grignard compounds of the general formula III, in which Z represents a halogen atom and R ² and η have the abovementioned meaning, in a molar ratio of approximately 1: 3. It has proved to be advantageous to prepare the title compounds I by combining solutions of the Grignard compounds of the general formula III in dialkyl ethers having 4 to 8 carbon atoms, cyclic ethers, such as 1,4-dioxane or tetrahydrofuran or in mixtures of the above solvents with aromatic Hydrocarbons, such as benzene