Metal-triflate ionic liquid systems immobilized onto mesoporous MS41 materials as new and efficient catalysts for N-acylation

Two kinds of MS41-immobilized ionic liquids (ILs) based on dihydroimidazolium and pyridinium cation were prepared using a grafting method. The second immobilization of triflate salts on these materials led to the immobilization of metal-triflate complexes into ILs. The materials thus obtained were characterized by 1H NMR, XRD, N2-sorption measurements, TG–DTA, DRIFT, XPS, TEM, and ICP-AES. The catalysts were tested in acylation of amines and sulfonamides and proved highly active and selective. For both aromatic and aliphatic amines, acylation with carboxylic acids was possible. For sulfonamides, acylation was possible only with anhydrides. Recycling the catalysts was not accompanied by any leaching of ILs or metal triflate.