Synthesis and Functionalization of N-Heterocycles Using Transition Metal-Free Cross-Dehydrogenative Coupling (CDC) Approaches



The creation of carbon–carbon bonds for the construction or the post-functionalization of various N-heterocycles is one of the most active research areas in organic chemistry. Among those approaches, cross-dehydrogenative coupling (CDC) processes in the front line because of its simple, practical applicability in organic synthesis. Historically discovered in the presence of transition metal catalysts, this decade witnessed great progress in the metal-free CDC approaches, thus improving the sustainability of this transformation. This chapter aims at providing an update on selected examples of the metal-free approaches toward the access to various N-heterocycles. The first part deals with the synthesis of N-heterocycles by metal-free CDC approaches in the presence of stoichiometric or catalytic amount of oxidants, whereas the second part is focused on the last stage C–H bond functionalization of N-heterocycles via CDC process.


Functionalization of amines Oxidant Metal-free approaches 



1-Butylpyridinium iodide




Benzoyl peroxide


Dicumyl peroxide




Di-tert-butyl peroxide


Ionic liquids


Potassium hexamethyldisilazide


meta-Chloroperoxybenzoic acid












Tetrabutylammonium bromide


Tetrabutylammonium iodide


tert-Butyl hydroperoxide




Trifluoroacetic acid


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© Springer Nature Singapore Pte Ltd. 2019

Authors and Affiliations

  1. 1.Department of Organic Synthesis and Process ChemistryCSIR—Indian Institute of Chemical Technology (CSIR-IICT)HyderabadIndia
  2. 2.Academy of Scientific and Innovative Research (AcSIR)GhaziabadIndia
  3. 3.Univ Rennes, UMR 6226 (Institut Des Sciences Chimiques de Rennes)RennesFrance

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