Starch Sulfuric Acid an Effective Catalyst for the Synthesis of Tetrahydroacridinone Derivatives

Recent developments in 1,4-dihydropyridine chemistry and our continued interest in the development of efficient and environmentally friendly procedures for the synthesis of heterocyclic compounds, prompted us to study the conversion of dimedone into fused 1,4-dihydropyridines in the presence of starch sulfuric acid as hetero-geneous catalyst by the reaction of aldehyde (10 mmol), dimedone (10 mmol) and ammonium acetate (10 mmol) in the presence of Starch sulfuricacid (Scheme 1)