Recent Advances in Intramolecular Metal‐Free Oxidative C–H Bond Aminations Using Hypervalent Iodine(III) Reagents

Hypervalent iodine chemistry is a rapidly growing area of research with tremendous impact on synthetic chemistry in the past years. A rich and diverse chemistry is now available for reactions using hypervalent iodine reagents, as metal‐free, ecofriendly reagents and the advent of new reactions will be of large benefit to researchers working in the area of selective synthesis. In this review article, we emphasize the usage of hypervalent iodine(III) reagents for metal‐free intramolecular oxidative C–N bond formation/annulation to synthesize wide range of N‐heterocycles in organic synthesis. The functionalization of C–H bonds through the involvement of sp‐, sp2‐, and sp3‐hybridized carbon atoms for cyclizations is discussed in detail. Hypervalent iodine(III) reagents are valuable oxidants with soft, non‐toxic, and environmentally friendly features. These reagents are successfully applied for the cyclization/annulation through a C–H bond functionalization of sp‐, sp2‐, and sp3‐hybridized carbon atoms. In this review article, the use of hypervalent iodine(III) reagents for metal‐free intramolecular oxidative C–N bond formation reactions to produce the immense array of N‐heterocyclic compounds in synthetic organic chemistry is highlighted.