Synthesis of novel benzimidazole derivatives and their platinum (II) complexes.

• Other Authors: Soares, A. M.
• Language: en
• Published: 2011
• Subjects: Imidazoles > Synthesis.; Imidazopyridines.; Heterocyclic compounds.; Chemistry > Theses.; Pyridine.
• Online Access: http://hdl.handle.net/10413/2612

Imidazo[1,5-a]pyridines are an important and versatile class of N-heterocyclic compounds due to their stability, unique biological, and photochemical properties. Due to the conjugation and charged structure, their properties are extended to conducting electricity and also have electronic properties. They can be used for chelating transition metals especially heavy metals that can be harmful to living things (including human). The aim of this research was to develop more useful imidazo[1,5-a]pyridines which are stable in both free and complexed state. A variety of imidazo[1,5-a]pyridyl compounds was synthesized following three useful methods namely (i) The first route includes the isolation of imine intermediates which were then treated with phosphorus oxychloride in one case and hydrochloric acid in another case as catalysts. Both cases resulted in the yield of the same imidazo[1,5-a]pyridyl compounds. (ii) The second route was the development on the first route for those imine intermediates that could not be isolated and only hydrochloric acid catalyst was used. In both the first and second routes, paraformaldehyde was used for the ringclosure step of the reaction. The last route for the formation of imidazo[1,5-a]pyridyl compounds did not involve the use of the paraformaldehyde reagent. The suitable routes were followed depending on the nature of the targeted products and the reaction yields were moderate to excellent. === Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg,2010.