Hetero-Bimetallic Complexes Based on an Anthyridine Ligand Preparation and Catalytic Activity
Journal
Organometallics
Journal Volume
39
Journal Issue
1
Pages
123-131
Date Issued
2020
Author(s)
Abstract
Complexation of anthyridine-based ligand L with [(η6-cymene)RuCl2]2, [Cp*RhCl2]2, and [Cp*IrCl2]2 yielded a mononuclear complex: [(N,N-L)Ru(η6-cymene)Cl]Cl (1), [(N,N-L)Rh(Cp*)Cl]Cl (2), and [(N,N-L)Ir(Cp*)Cl]Cl (3), respectively [L = 5-phenyl-2,8-di-2-pyridinylanthyridine]. Upon treatment with (CH3CN)PdCl2, complexes 1–3 underwent o-metalation to yield heterobimetallic complexes Ru–Pd, Rh–Pd, and Ir–Pd, respectively. Complexes were all characterized by spectroscopic method, and some are further confirmed by X-ray crystallography. Complex Ru–Pd exhibits catalytic activities for the tandem reactions of Suzuki–Miyaura coupling/transfer hydrogenation of p-bromoacetophenone with phenylboronic acid in isopropanol, whereas Ir–Pd shows a moderate activity. However, complex Rh–Pd does not behave the same way. Furthermore, catalytic activity of these heterobimetallic complexes toward debromination/transfer hydrogenation of p-bromoacetophenonewas also investigated. The catalytic pathways of these processes were studied and discussed. This study reveals the base used in the reactions plays an important role in the reaction pathway.
Type
journal article