New Research on Dihydropyridines

Dihydropyridines (DHPs) are one of the most important nitrogen-containing heterocycles which are widely recognized in the scaffold of various biologically active compounds and natural products. DHPs are also utilized as medicines and useful building blocks for the complex molecules. On the other hand, some DHPs exhibit blue fluorescence in organic solvents and have potential to apply as functional materials. Based on the novel utility of DHPs in both medicinal chemistry and material sciences, development of efficient and robust synthetic methods for DHPs has been paid much attention and a large number of synthesis of DHPs have been reported. The first chapter in this book summarizes recent progress in synthetic methodologies for the construction of DHP scaffolds both in catalytic and in stoichiometric manners (particularly from 2000 to present), which are classified by the reaction patterns as 1) Multi-Component Coupling Reactions, 2) Pericyclic Reactions, 3) Regioselective Transformation of Pyridines, and 4) Miscellaneous. Chapter Two focuses on the synthesis of 1,4-DHPs and derivative compounds by using different routes of synthesis and greener alternatives. Chapter Three describes a mild and efficient protocol for the synthesis of 1,4-dihydropyridines via four component reactions of aromatic aldehydes, dimedone, ethyl acetoacetate or methyl acetoacetate and ammonium acetate using Fe(ClO4)3/SiO2. Chapter Four reviews the synthesis of chiral dihydropyridines.