Heteropoly Acid Catalyzed Micheal Addition of Benzene Sulfonamide to Ethyl Acrylate

Abstract

The solvent-free aza-Michael addition reaction of benzene sulfonamide to ethyl acrylate carried out in presence of catalytic amount of different. Keggin type heteropoly acids as reusable catalyst in solvent-free condition has been investigated. Pure N-alkylsulfonamide was obtained and the structure of N-alkylsulfonamide was identified by GC-MS, FT-IR and ¹H NMR spectra. It is found that H₃PW₁₂ had the best activity affording N-alkylsulfonamide with excellent yield of 93 %. The effects of experimental factors on the catalytic aza-Michael addition reaction and the catalytic recycling of H₃PW₁₂ catalyst were studied. H₃PW₁₂ catalyst exhibited good catalytic activity after 5 times of running. The undemanding catalytic separation and the reusability of the H₃PW₁₂ catalyst is hopefully to be beneficial to the exploration of green chemistry and environmental benign procedure for the synthesis of N-alkylsulfonamide.