Transition‐Metal‐Catalyzed Remote C(sp3)−H Functionalization Of Carboxylic Acid And Its Derivatives

Abstract Carboxylic acids are ubiquitous functional groups present in many bio‐relevant molecules, including drugs and amino acids. In general, α‐ and β−C(sp 3 )−H bonds of carboxylic acids are easy to functionalize, contrary to remote (γ‐ and δ) C−H bonds which are difficult due to the distal location of these C−H bonds from the functional group. On the other hand, functionalizing an inert C(sp 3 )−H bond is another critical challenge in synthetic chemistry due to its lower acidity and reactivity. Nevertheless, the last decade has witnessed tremendous development in remote sp 3 ‐C−H bond functionalization of carboxylic acid and its derivatives. Here, in this review, we have delineated recent progress in remote γ‐ and δ‐C−H bond functionalization of aliphatic carboxylic acids/amino acids and their derivatives. This review is further subdivided based on the type of functionalization reaction. Finally, we have presented some applications of these methodologies, such as total synthesis of hibispeptin A, etc.