Study On Synthesis Of Intermediatas For Vinylsulphone Reactive Dyes

Vinyl sulfone reactive dyes are a kind of dye with excellent properities. They weredominant in the dyestuff market and show better application prospect. Therefore it isof great significance to explore synthetic process of vinylsulfone type reactive dyeintermediates.The task is mainly divided into the following three parts:(1) the vinylsulfonereactive dye intermediate while contains benzothiazolyl group2-amino-6-sulfonamideethoxyacetyl benzothiazole was designed and synthesized;(2) the structures of thesynthesized compounds were characterized by1H NMR,13C NMR, MS and IRspectra.(3) different synthesis methods and the reaction conditions in the syntheticprocedures were explored, the optimal synthetic conditions were found. The essaymainly include the following content.1. Synthesis route1.4-Nitrophenyl-2-hydroxyethyl sulfide (product1) wasobtained as main product by the reaction between4-nitro-chlorobenzene and β-mercaptoethanol, the yield is93.4%.4-aminophenyl-2-hydroxyethyl sulfide (product2) was obtained from reduction of the nitro group in Product1with hydrazine hydrateand Raney-Ni, the yield is95.1%.4-acetylaminophenyl-2-acetoxyethyl sulfide(product3) was obtained by acetic anhydride amidation and esterification, the yield is90.6%.4-acetylaminophenyl-2-acetoxyethyl sulfone (product4) was obtained byoxidation by product3with hydrogen peroxide, the yield is90.3%.4-aminophenyl-2-acetoxyethyl sulfone (product5) was obtained from hydrolysis ofproduct4, the yield is78.5%. At last2-amino-6-sulfonamide ethoxyacetyl benzothiazole (the intermediate compound6) was obtained by the reaction betweenthe compound5and potassium thiocyanate, the yield is62.2%. The total yield is35.4%.2. Synthesis route2.4-nitro-benzenesulfinic acid (product7) was obtained by thereaction between4-nitro-benzenesulfonyl chloride, Sodium sulfite and Sodiumbicarbonate, the yield is82.6%.4-nitrophenyl-2-hydroxyethyl sulfone (product8) wasobtained by condensation reaction, the yield is88.4%.4-aminophenyl-2-hydroxyethylsulfone (product9) was obtained from reduction of product8, the yield is93.4%. Thefinal product6was obtained by the reaction of esterification, hydrolysis andcyclization. The total yield is27.4%.3. Synthesis route3.4-Acetylamino-benzenesulfinic acid (product10) wasobtained by the reaction between4-acetylamino-benzenesulfonyl chloride, sodiumsulfite and sodium bicarbonate, the yield is84.3%.N-[4-(2-Hydroxy-ethanesulfonyl)-phenyl]-acetamide (product11) was obtained bycondensation reaction, the yield is90.5%. The final product6was obtained by thereaction of esterification, hydrolysis and cyclization. The total yield is37.3%.4. Synthesis route4.4-Amino-benzenethiol (product12) was obtained by thereaction between4-nitro-chlorobenzene and14%sodium sulfide solution, the yield is85.4%. Product2was obtained by the reaction of condensation using oxirane, theyield is30.7%. Then compound6was obtained by amidation and esterification,oxidation, hydrolysis and cyclization reaction as the essay described above. The totalyield is10.5%.