Iron-Catalyzed Cross-Electrophile Coupling of Inert C–O Bonds with Alkyl Bromides

Iron-catalysed reductive coupling for the synthesis of polyfluorinated compounds

“…On the basis of the experimental results aforementioned and the previous reports, 4–17 we proposed a radical-type mechanism for this Fe-catalysed defluorinative cross-coupling reaction (Scheme 6). At the beginning, Fe + complex I is formed under reductive reaction conditions, 14 followed by single-electron-transfer with the bromodifluoroacetate 2a .…”

“…Feng's group disclosed a reductive cross-coupling of aryl carbamates with alkyl bromides under an iron/B 2 pin 2 catalytic system (Scheme 1c). 17 Inspired by the above works, we envisioned that the use of ironcatalysis could induce difluorobromoacetates 18 to form carbon radicals under reductive conditions, which will undergo radical addition to trifluoromethyl olefins followed by b-F elimination to afford the corresponding gem-difluoroolefins. Herein, we set out to develop an iron-catalysed cross-electrophile coupling reaction for the synthesis of gem-difluoroolefins (Scheme 1d).…”

“…Feng's group disclosed a reductive cross-coupling of aryl carbamates with alkyl bromides under an iron/B 2 pin 2 catalytic system (Scheme 1c). 17…”

Recent Progress in Transition-Metal-Catalyzed Reductive Cross-Coupling Reactions Using Diboron Reagents as Reductants

“…Very recently, the Feng group reported an example of electrophilic cross-coupling involving alkyl bromides with inert (hetero)­aryl carbamates under iron catalysis, facilitated by B 2 pin 2 and LiOMe (Figure ). It should be noted that the success of the reaction could be attributed to the use of B 2 pin 2 as the reductant and LiOMe as the base. Intriguingly, other reductants (tetrakis­(dimethylamino)­ethylene, Mn, and Zn) and other bases (KOMe and NaO t -Bu) failed to promote this transformation.…”

A one-pot protocol for iron-catalyzed decarbonylative borylation of aryl and alkyl carboxylic acids

“…Our recent work found that high-valent iron species could be reduced to in situ generate the highly reactive iron species with the diborane reagents and alkali metal alkoxides systems, such as B 2 pin 2 / t -BuOLi, thus allowing the borylation and silylation of unreactive bonds. 5 , 6 , 7 , 8 , 9 , 10 …”