Metal-Free Synthesis of Heterocycles via Cross-Dehydrogenative Coupling

Abstract

The synthesis of heterocyclic molecules has always been a central theme in organic chemistry since centuries. Numerous methodologies have been developed towards the construction of complex heterocyclic molecules. The traditional approaches generally involve the use of preactivated substrates as the essential requirement, thus making the overall method tedious and expensive. Working towards the development of greener and sustainable approach, metal-free cross-dehydrogenative coupling strategies have emerged as a boon to the synthetic chemists. The method is straightforward eliminating the pre-functionalization steps and avoiding the toxicity imposed by the metal impurities. This chapter illustrates various metal-free cross-dehydrogenative tactics for the synthesis of different N, O, and S based heterocyclic molecules with few representative examples in each case along with the mechanism demonstrating the synthesis of respective molecule.