Chapter 4 - A chapter on synthesis of various heterocyclic compounds by environmentally friendly green chemistry technologies

Abstract

Advancement of green chemistry carried out various challenges to those who applied chemistry in medicine industry, education and research. The start of green chemistry is considered as a revolution to the need to reduce the environment damage and human health risk by synthetic chemicals and the methods used to synthesized them. The preferable application of green chemistry in research is to use environment benign, mild, non toxic, reproducible catalyst and efficient solvents in synthesis of chemical compounds. The principles of green chemistry directed to designing new organic compounds and procedures in such a manner that they reduced their impact on the environment. Various reports related to synthesis of heterocyclic compounds containing N, O and S heteroatom in their cyclic structures and have exhibited wide varieties of their biological activities. Recently various informations regarding the synthesis of heterocyclic compounds under solvent-free, reactants immobilized on solid support and microwave irradiation state has been come out. In this review, discussed the important role of solvent-free condition coupled with microwave activation and their advantages in the synthesis of imidazoles, triazines, triazoles, benzimidazoles, benzoxazoles, oxadiazoles and benzothiazoles. Use of microwave irradiation directed too many advantages, such as the use of non-corrosive and inexpensive chemicals and reagents, in addition to the eco-friendly “green chemistry” inexpensive and environmental impacts.