Emerging trends in C(sp3)–H borylation

Along with the advancement of metal complexes, ligand families, and boron reagents, some innovative and sustainable methods for C(sp3)–H bond borylation have emerged. The borylation of C(sp3)–H bonds has been reported via both transition-metal catalysis and metal-free conditions. For the regio- and enantioselective borylation of remote C(sp3)–H bonds, the association of an iridium catalyst, chiral monophosphite ligand, and receptor ligand system provides a creative and effective catalytic approach. The unique chemistry of the bidentate boryl ligand offers inspiring opportunities for the development of new asymmetric C–H borylation processes. The emergence of light-induced radical strategies has provided exciting possibilities for metal-free, selective C(sp3)–H borylation. C–H bond activation and functionalization has been the subject of intensive research efforts in organic synthesis due to their special relevance both academically and industrially. In particular, C–H borylation represents a highly atom- and step-economic approach toward the generation of organoborons. As a result of ubiquity and low reactivity of alkanes, controlling both the chemo- and site-selectivity of C(sp3)–H borylation constitutes a significant challenge. Herein we highlight the representative examples in the field. Our analysis serves to document the emerging trends in C(sp3)–H borylation, while also pointing out the limitations of current methods. C–H bond activation and functionalization has been the subject of intensive research efforts in organic synthesis due to their special relevance both academically and industrially. In particular, C–H borylation represents a highly atom- and step-economic approach toward the generation of organoborons. As a result of ubiquity and low reactivity of alkanes, controlling both the chemo- and site-selectivity of C(sp3)–H borylation constitutes a significant challenge. Herein we highlight the representative examples in the field. Our analysis serves to document the emerging trends in C(sp3)–H borylation, while also pointing out the limitations of current methods. a sequence of β-hydrogen eliminations and migratory insertions that isomerizes an unsaturation through an aliphatic system. a functional group in the vicinity of the reaction center that generates attractive substrate–reagent interaction and controls the trajectory of the incoming reagent. This phenomenon is also described as the complex-induced proximity effect. a reaction that cleaves an A–B bond forming two new covalent bonds between a metal center (M) and the A and B residues (A–M–B). During this process, the metal is formally oxidized by two electrons and the coordination number of the metal center increases. This is often the first step of organometallic catalytic cycles. opposite reaction of oxidative addition where two metal–ligand bonds are cleaved and a new bond between those ligands is formed. During this process, the metal is formally reduced by two electrons and the coordination number of the metal center decreases. This is typically the last step of organometallic catalytic cycles. the preference of a direction in which a chemical bond is formed or broken. Regioselective reactions discriminate different potentially reactive positions in a molecule. the transfer of a single electron from a molecular entity to another, or between two localized sites in the same molecular entity.