Cobalt-Catalyzed Alkynylation of Organic Compounds: Hydroalkynylation, Dehydrogenative Alkynylation, and Reductive Alkynylation

Abstract

Cobalt-catalyzed hydroalkynylation of alkynes, alkenes, and imines affords internal alkynes with various functional groups adjacent to the carbon-carbon triple bond moiety in an atom-economical manner. In addition, cross-coupling of in situ-generated alkynylcobalt species from terminal alkynes, haloalkynes, and metal acetylides with (hetero)aromatic compounds and organic halides selectively provides various internal aryl- and alkylalkynes. 1 Introduction 2 Hydroalkynylation of Alkynes for 1,3-Enyne Synthesis 3 Hydroalkynylation of Polar and Non-polar Double Bonds 4 Dehydrogenative Cross-coupling Reaction Using Terminal Alkynes with Aromatic Compounds 5 Cross-coupling Reactions Using Haloalkynes as the Coupling Partners 6 Cross-coupling Reactions Using Metal Acetylides 7 Conclusion

Cobalt-catalyzed cross-electrophile coupling of alkynyl sulfides with unactivated chlorosilanes

“…A , which was subsequently reduced by Zn to provide a more nucleophilic alkynyl Co I Int. B 62 , 63 . The S N 2 oxidative addition of chlorosilanes to Int.…”

Cobalt Hydride-Catalyzed Hydroalkynylation of Alkenes with Alkynyl Trifluoroborates

“…Among many established strategies, transition-metal-catalyzed hydroalkynylation of alkenes is a highly attractive and powerful strategy for the synthesis of alkyne-containing compounds . Leveraged the CC bonds insertion into in situ generated metal-acetylides or metal-hydride species, a series of catalytic hydroalkynylation of alkenes with alkynyl reagents, such as terminal alkyne, alkynyl bromides and ethynylbenziodoxolones, have been developed under Ir, Ni, Co, Pd, and Au catalysis (Scheme A). Complementing these polar strategies, radical hydroalkynylation of alkenes, i.e., intercepting a carbon-centered radical, also serves as a versatile and fascinating strategy for the installation of alkynyl functional groups in recent years .…”