ABSTRACT
On-surface assembly of a spin-bearing and non-aromatic porphyrin-related synthetic Co(II)-complex on a ferromagnetic Ni thin film substrate and subsequent magnetic exchange interaction across the interface were studied by scanning tunnelling microscopy (STM), X-ray absorption spectroscopy (XAS), X-ray magnetic circular dichroism (XMCD) and density functional theory +U (DFT + U) calculations.
ABSTRACT
Carbazole-containing porphyrinoid was synthesised for the first time via Suzuki-Miyaura cross-coupling reaction. Oxidation with MnO(2) yielded its porphyrin-state featuring macrocyclic aromaticity in exchange for the loss of the resonance energies of the benzene rings.
Subject(s)
Carbazoles/chemistry , Porphyrins/chemical synthesis , Molecular Structure , Oxidation-Reduction , Porphyrins/chemistryABSTRACT
A new class of macrocyclic metal-N(4) complexes [MN(4)](n) (M = Co and Fe) were designed and synthesized based on a triangular ligand. Their unique triangular trinuclear structure provides a high density of active sites and facilitates the reduction of dioxygen via a four-electron pathway. Among them, a [CoN(4)](3)/C catalyst (20 wt %) exhibits high catalytic activity and long-time stability for the oxygen reduction reaction (ORR) in alkaline conditions, superior to the commercial Pt/C catalyst. Such structurally well-defined [MN(4)](n) complexes provide a platform for a new generation of nonprecious metal catalysts (NPMCs) for fuel cell applications.
ABSTRACT
In this communication, we report the synthesis of a novel porphyrin-related macrocycle. The core modifications result in aromatic building blocks connected exclusively via aryl-aryl bonds. The concept of synthesis permits the formation of a cavity similar to that of a porphyrin combined with the ability to bind metal ions to provide neutral metal complexes.
