MODERN AZIDATION TECHNIQUES OF ALIPHATIC C-H BOND FUNCTIONALIZATION

Abstract

The azidation of the ubiquitous C-H bond can lead to the creation of numerous biologically relevant molecules. Azidated organic molecules are often times recognized as useful precursors for a wide range of nitrogen based biological molecules or for therapeutic drugs. Due to the importance of the functionality of the azide group in molecules in synthetic chemistry or pharmaceuticals, the synthetic repertoire for making these azidated molecules through azidation of the C-H bond is actively being expanded. Through the lens of the much more understood fluorination reaction, the progress of modern azidation reactions is surveyed here. Modern techniques of these azidation reactions generally involve the production of a carbon centered radical through a hydrogen atom transfer step and then followed by a reaction to bond an azide with the produced radical. There are also a few cases where the carbon centered radical and an azide radical work together to give the azidation product. Generally, these methods fall into three categories: directing group mediated azidation, metal-free azidation, and metal-catalyzed azidation which all have the goal of creating a selective pathway for azidation. Taking control of the ubiquity of the C-H bond and the versatility of the azide molecule could have large implications on various fields of study.