Preparation method of sulfonanilide compound

Abstract

The invention discloses a preparation method for a sulfonanilide compound, which comprises the following steps: adding 1-10 parts by mol of an aprotic dipolar solvent into a reactor, raising the temperature of the reactor to 90-136 DEG C while stirring, adding 0.001-0.1 part by mol of a catalyst, stirring the mixture, dropping 1-10 parts by mol of a sulfonated agent and carrying out a sulfonylation reaction for 10-25h at 90-136 DEG C, and cooling, filtering, washing and baking the reaction product, then obtaining the sulfonanilide compound. The catalyst adopted by the invention is triphenylphosphine, polyethylene glycol or crown ether instead of the former expensive catalysts including tetrabutyl amonium bromide and DMF, while the reaction conversion rate is above 99%, the reaction effect is better, the side reactions are less, and high-purity products are obtained in high yield. With simple technique, low cost of catalyst and few side reactions, the invention is suitable for large-scale industrial production.

Description

technical field [0001] The invention relates to the technical field of fine chemicals, in particular to a preparation method of sulfonyl anilide compounds. Background technique [0002] It is well known that some substituted sulfonanilides possess herbicidal activity and this has led to some useful compounds for the preparation of herbicides. For example, U.S. Patent [US 4818275] discloses sulfentrazone (N-(2,4-dichloro-5-(4-difluoromethyl-4,5-dihydro-3-methyl-5-oxo Generation-1 hydrogen-1,2,4-triazol-1-yl)phenyl)methanesulfonamide) as a herbicide. In this patent, sulfentrazone (N-(2,4-dichloro-5-(4-difluoromethyl-4,5-dihydro-3-methyl-5-oxo-1H- 1,2,4-triazol-1-yl)phenyl)methanesulfonamide) is prepared as follows: 1-(5-amino-2,4-dichlorophenyl)-4-difluoromethyl-3 -Methyl-1 hydrogen-1,2,4-triazol-5 (4 hydrogen) ketone and methanesulfonyl chloride take haloalkane as solvent, take triethylamine as base first to generate bis-methanesulfonamide, then in sodium hydroxide Under ...

AI Technical Summary

Problems solved by technology

The ensuing problem is exactly: one, in this reaction process, triethylamine or pyridine must be excessive to complete reaction as acid-binding agent, can produce a lot of triethylamine hydrochloride or pyridine hydrochloride and A large amount of waste water, high raw material costs and environmental costs make this method unsuitable for large-scale industrial production; second, each molecule of product needs to consume one more molecule of methanesulfonyl chloride, and the result is neither economical nor environmentally friendly; third, using hydrogen Sodium oxide treatment of bis-methylsulfonyl compounds yields low yield of product sulfentrazone

U.S. Patent [US 5990315] discloses direct sulfonylation reactions catalyzed by soluble salts such as quaternary ammonium salts and quaternary phosphonium salts. Although this method solves the problem of direct sulfonylation reactions, the catalyst used is relatively expensive, and the simultaneous reaction The yield is not high

U.S. Patent [US 7169952] reported the direct sulfonylation reaction catalyzed by DMF and other high-boiling amides and tertiary amines. This method uses cheap catalysts to solve the problem of direct sulfonylation reaction, but at the same time it will produce higher content of impurities. affect product quality

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