**4. Conclusion**

In this chapter, I had listed the reactions using green methodologies for the synthesis of nitrogen heterocyclic compounds. These molecules often have interesting biological activities and are structures often generated in medicinal chemistry. Recently, numerous publications concerning the synthesis of heterocycles under solvent-free, use of bio-based solvent, reactions carried on solid support, microwave irradiation condition have appeared. Work on the use of green reactions leading to the formation of nitrogen heterocycles mainly indole, pyrrole, imidazole, pyrimidine, pyridine derivatives is reported in the present chapter using safe solvents, namely water, various bio-based systems is discussed. Green synthetic reactions using

microwaves for the one pot synthesis of N-heterocyclic compounds is of immense utility in terms of yield, being faster, cheaper, eco-friendly than conventional reactions. I hope that gathering information will enable the scientific community to implement heterocyclic syntheses that respect our environment a little better.
