Recent Expedition in Pd‐ and Rh‐Catalyzed C_(Ar)−B Bond Formations and Their Applications in Modern Organic Syntheses

Abstract

Transition metal‐catalyzed borylation has emerged as a powerful and versatile strategy for synthesizing organoboron compounds. These compounds have found widespread applications in various aspects, including organic synthesis, materials science, and medicinal chemistry. This review provides a concise summary of the recent advances in palladium‐ and rhodium‐catalyzed borylation from 2013 to 2023. The review covers the representative examples of catalysts, substrates scope and reaction conditions, with particular emphasis on the development of catalyst systems, such as phosphine ligands, NHC‐carbene, and more. The diverse array of borylative products obtained for further applications in Suzuki‐Miyaura coupling, and other transformations, are also discussed. Future directions in this rapidly evolving field, with the goal of designing more efficient, selective borylation methodologies are highlighted, too.

Isolation and Reactivity of Arylnickel(II) Complexes in Nickel-Catalyzed Borylation of Aryl Fluorosulfates

“…Organoborons have gained recognition as key organometallic reagents owing to their synthetic versatility, bench stability, low toxicity, and ease of handling. − Recent progress in palladium-catalyzed C–B bond formation, including the Miyaura borylation of aryl halides, has paved the way for the establishment of straightforward and reliable routes to prepare arylboron compounds. − However, comparatively less attention has been focused on elucidating the reaction pathways in nickel-catalyzed processes. , Nickel catalysts, in addition to being cost-effective, exhibit superior performance compared to palladium ones in activating less reactive electrophiles such as pseudohalides, esters, or even ethers. , Despite these advantages, nickel can exist in diverse oxidation states, and the facile interconversion between these states can pose challenges in controlling the desired reactivity. − Furthermore, the requirement of relatively high catalyst loading limits the practical application of nickel catalysis. Therefore, gaining a comprehensive understanding of the reaction mechanism, especially when it involves the activation of C–O bonds, is crucial.…”

“…1 − 6 Recent progress in palladium-catalyzed C–B bond formation, including the Miyaura borylation of aryl halides, has paved the way for the establishment of straightforward and reliable routes to prepare arylboron compounds. 7 − 10 However, comparatively less attention has been focused on elucidating the reaction pathways in nickel-catalyzed processes. 11 , 12 Nickel catalysts, in addition to being cost-effective, exhibit superior performance compared to palladium ones in activating less reactive electrophiles such as pseudohalides, esters, or even ethers.…”