Recent advances in C-H functionalizations assisted by removable and/or modifiable directing groups

Abstract

Transition-metal catalyzed chelation-assisted C-H bond functionalization is one of hot topics in current organic chemistry. Recently, using removable and/or modifiable directing groups for C-H bond functionalizations has being received specially attention and developed rapidly. By taking advantage of removable and/or modifiable directing groups, it not only greatly expands the scope of substrates for C-H fuctionalization, but also plays important roles in rapid construction of molecule diversity. Based on the classification according to different hetero-atom (N, O, S, and Si) donors, this review presents the state of the art in design of removable and/or modifiable directing groups for transition-metal catalyzed C-H functionalizations and their application in construction of molecule diversity. Finally, the existing problems and limitations of this field are summarized, and the outlook of the area is also prospected. © 2014 Chinese Chemical Society & SIOC, CAS.