Multi walled carbon nanotubes supported N-heterocyclic carbene–cobalt (ΙΙ) as a novel, efficient and inexpensive catalyst for the Mizoroki–Heck reaction

•The first time report of N-heterocyclic carbene–cobalt complex (NHC-Co2 +) immobilized onto the surface of multi-walled carbon nanotubes.•The introduced catalyst is air stable, highly active and reusable without toxic ligands.•This paper presents a facility and high efficiency strategy for the Heck reaction using green solvents and mild conditions.

In this paper, an N-heterocyclic carbene–cobalt complex (NHC–Co2 +) was immobilized onto the surface of multi-walled carbon nanotubes (MWCNTs) via direct grafting amination approach for the first time. The resultant composite (Co-–NHC@MWCNTs) was characterized by FT-IR, TGA, XRD, ICP-OES, FE-SEM, TEM and CHN analyses. It was demonstrated that Co–NHC@MWCNTs can act as an efficient and inexpensive catalyst for Heck reactions in normal conditions which provided the corresponding products in moderate to good yields. More importantly, this phosphine and palladium-free catalyst can be reused for at least six successive runs without any discernible decrease in its catalytic activity and no remarkable changes were observed in catalyst structure.

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