Electroreductive Cross‐Electrophile Coupling (eXEC) Reactions

Abstract

Electrochemistry utilizes electrons as a potent, controllable, and traceless alternative to chemical oxidants or reductants, and typically offers a more sustainable option for achieving selective organic synthesis. Recently, the merger of electrochemistry with readily available electrophiles has been recognized as a viable and increasingly popular methodology for efficiently constructing challenging C−C and C‐heteroatom bonds in a sustainable manner for complex organic molecules. In this mini‐review, we have systematically summarized the most recent advances in electroreductive cross‐electrophile coupling (eXEC) reactions during the last decade. Our focus has been on readily available electrophiles, including aryl and alkyl organic (pseudo)halides, as well as small molecules such as CO2, SO2, and D2O.

P,N Ligand in Ni-Catalyzed Cross-Coupling Reactions: A Promising Tool for π-Functionalization

“…In 2022, a seminal report from the Sevov group implemented a synergistic dual ligand strategy into electroreductive XEC to allow the coupling of a previously incompatible pair of electrophiles (Figure B) . In the reaction, 10 mol % NiCl 2 DME/ i PrQ ( L10 ) and 10 mol % (bpp)­MnCl 2 delivered a broad scope of coupling products from aryl- and alkenyl (pseudo)­halides with tertiary alkyl bromides.…”

Transition-Metal-Free Electrochemical Selenylative Cyclization of Alkynyl Phosphonates

“…On the other hand, sustainable electrochemical organic synthesis has been recognized as an important tool in heterocycle constructions. , Recently, elegant electrochemical C–H phosphorylation was achieved by Lei, Ackermann, Xu, and others . However, to the best of my knowledge, there are few reports regarding the electrochemical cyclic enol phosphonate synthesis .…”

Palladium(I)-Iodide-Catalyzed Deoxygenative Heck Reaction of Vinyl Triflates: A Formate-Mediated Cross-Electrophile Reductive Coupling with cine-Substitution

“…Such methods bypass the use of premetalated C -nucleophiles, which are often hazardous and expensive. In an outgrowth of this work, the first carbonyl reductive couplings of aryl halides beyond discrete arylmetal nucleophiles or metallic reductants were discovered, along with related formate-mediated reactions of vinyl halides or triflates. , The ability to exploit sp 2 halides as aryl- and vinylmetal pronucleophiles in formate-mediated carbonyl addition impelled investigations into “cross-electrophile reductive couplings”an emerging class of C–C couplings that typically require elemental zinc or manganese as the terminal reductants. − Here, we report formate-mediated reductive cross-couplings of vinyl triflates with aryl iodides, which, unlike long-standing palladium(0)-catalyzed cross-couplings of vinyl triflates, , result in cine -substitution through a deoxygenative Heck-type pathway (Figure ). − Our collective data corroborate a mechanism in which Pd­(OAc) 2 and Bu 4 NI form the dianionic iodide-bridged dimer [Pd 2 I 6 ]­[NBu 4 ] 2 , which, under reducing conditions, serves as a reservoir for the active palladium­(I) complex [Pd 2 I 4 ]­[NBu 4 ] 2 .…”