Carbon(sp²)‐carbon(sp³) Bond‐forming Cross‐coupling Reactions Using Sulfur‐Modified Au‐Supported Nickel Nanoparticle Catalyst

Abstract

We report a carbon(sp2)‐carbon(sp3) bond‐forming cross‐coupling reactions by employing a nano‐size nickel catalyst supported on sulfur‐modified gold (SANi). This transformation demonstrates an efficient synthesis of functionalized aryl compounds, including heterocycles. Notably, the reactions proceeded in good yields with significantly low leaching of nickel from SANi. Moreover, SANi could be recycled several times without significant loss of catalytic activity.

Ligand-free reductive coupling of aldehydes with 1,3-dienes using a sulfur-modified Au-supported nickel nanoparticle catalyst

“…About 3 nm sized Ni NPs are supported and stabilized by the self-assembly of sulfate ions and a durene polymer, similar to SAPd. 18…”

“…About 3 nm sized Ni NPs are Table 3 Reductive coupling of aldehydes with 1,3-dienes using SANi; substrate scope supported and stabilized by the self-assembly of sulfate ions and a durene polymer, similar to SAPd. 18 Furthermore, SANi shows high catalytic activity in the Kumada and Negishi coupling reactions without the use of ligands and can be used repeatedly more than five times (Scheme 3a-c). 17 In these reactions, heterogeneous catalyst SANi shows unique characteristics; we speculate that just a tiny amount of Ni(0) NPs leave from the SANi surface and efficiently act as actual active species in these coupling reactions.…”