Ligand Steric Effects of α-Diimine Nickel(II) and Palladium(II) Complexes in the Suzuki–Miyaura Cross-Coupling Reaction
Citations Over TimeTop 20% of 2020 papers
Abstract
Nickel catalysts represent a low cost and environmentally friendly alternative to palladium-based catalytic systems for Suzuki-Miyaura cross-coupling (SMC) reactions. However, nickel catalysts have suffered from poor air, moisture, and thermal stabilities, especially at high catalyst loading, requiring controlled reaction conditions. In this report, we examine a family of mono- and dinuclear Ni(II) and Pd(II) complexes with a diverse and versatile α-diimine ligand environment for SMC reactions. To evaluate the ligand steric effects, including the bite angle in the reaction outcomes, the structural variation of the complexes was achieved by incorporating iminopyridine- and acenaphthene-based ligands. Moreover, the impact of substrate bulkiness was investigated by reacting various aryl bromides with phenylboronic acid, 2-naphthylboronic acid, and 9-phenanthracenylboronic acid. Yields were the best with the dinuclear complex, being nearly quantitative (93-99%), followed by the mononuclear complexes, giving yields of 78-98%. Consequently, α-diimine-based ligands have the potential to deliver Ni-based systems as sustainable catalysts in SMC.
Related Papers
- → Biosynthesis of palladium nanoparticles using Poplar leaf extract and its application in Suzuki coupling reaction(2016)11 cited
- → An efficient and recyclable water-soluble cyclopalladated complex for aqueous Suzuki reactions under aerial conditions(2009)41 cited
- → Preparation of Pd-Diimine@SBA-15 and Its Catalytic Performance for the Suzuki Coupling Reaction(2016)22 cited
- → Water‐Soluble and Recyclable Cyclopalladated Ferrocenylimine for Suzuki Coupling Reaction(2013)13 cited
- → Inhibition of Homo‐coupling of Arylboronic Acids in Ligand Free Pd(II)‐Catalyzed Suzuki Reaction(2007)6 cited