Zeolite Catalyzed Aldol Condensation Reactions

The review is based on the description of zeolite structure, uses, synthesis, and catalytic aldol reaction in aldol condensation. An internal aldol condensation reaction has been achieved over ZSM-5 zeolite with high silica-alumina ratio at 350°C. It therefore follows that zeolite can function as a catalyst in aldol type condensation reactions and that weak acid sites as well as a small number of active sites favor the aldol condensation reaction of carbonyl compounds. However, the mixed condensation product was found to be favored at temperatures above 300°C and the self-condensation of ethanal to crotonaldehyde was favored at temperatures below 3000C. It has also been suggested that both Broosted and Lewis acids are involved in aldol reactions with Lewis acid sites the most probable catalytic sites. The zeolite group of minerals has found use in many chemical and allied industries