42996-00-9Relevant articles and documents
Perchloric acid impregnated on silica gel (HClO4/SiO 2): A versatile catalyst for Michael addition of thiols to the electron-deficient alkenes
Khan, Abu T.,Ghosh, Subrata,Choudhury, Lokman H.
, p. 2226 - 2231 (2006)
Perchloric acid adsorbed on silica gel (HClO4X/SiO2) has been found to be a highly efficient and versatile catalyst for the Michael addition of thiols to a wide variety of conjugated alkenes such as α,α-unsaturated ketones, carboxylic esters, nitriles, amides and chalcones in dichloromethane or methanol at room temperature. The reactions are completed within 2-20 min in high yields. Some of the additional advantages are: no aqueous work-up is necessary, and the catalyst is also reusable. Moreover, the solid product can be obtained without chromatographic separation. Wiley-VCH Verlag GmbH & Co. KGaA, 2006.