Heterogeneously Catalyzed Synthesis of Heterocyclic Compounds

This chapter covers the synthesis of heterocyclic compounds using heterogeneous catalysts from the perspective of practicing industrial chemists. Before discussing the synthesis of various heterocycles using heterogeneous catalysts a brief discussion on catalyst choice and classification of reaction chemistry is provided. Next, the synthesis of commercially important heterocycles from acyclic precursors is provided starting with the three-membered aziridines and epoxides. For the four-membered heterocycles, propiolactone synthesis is discussed followed by the five-membered pyrroles, furans, and thiophenes. Within the five-membered ring category of heterocycles, the benz-fused pyrrole, indole and rings with more than one heteroatom such as pyrazoles, imidazoles, thiazoles, oxa- and thio-diazoles synthesis are also discussed. Similar to the five-membered ring heterocycles, the six-membered heterocycle syntheses discussed are pyridines, picolines, quinolines, acridines, pyrimidines, pyrazines, triazines, coumarins, etc. Finally a small section on process and economics consideration is provided along with final comments.