Organische Reaktionen an stark sauren Nafion-Silica nanokompositen Katalysatoren

Abstract

This paper decribes the study on several organic reactions over highly acidic Nafion/Silica catalysts. Via embedding nano-sized Nafion particles within a highly porous silica matrix, a nano-composite catalyst is manufactured, which got tremendously improved desorption and adsorption properties. This implies improvements in the catalytic activity. Due to the rigid silica framework, the acidic composite catalyst is even able to catalyze gaseous organic reactions. The scope of the explored organic reactions implies the dimerization of alpha-methlystyrene, Friedel Crafts acylation reactions, Fries rearrangements, electrophilic additions of carboxylic acids or water to monocyclic unsaturated carbohydrates, Pinacolon rearrangements and especially reactions in the vapour phase. In all studied reactions the impact of the solvent has been thoroughly discussed. The results were evaluated in comparison to alternative catalysts like acidic ion-exchange resins as well as to zeolithes e.g. H-BEA