Gold Nanosystem Catalyzed Precise Bromination of Aromatic Feedstock Enabled by Global-Vertexes Stabilization

Abstract

Ligand advancements have propelled the development of sophisticated ligand strategies for nanocatalysis. These strategies offer the tantalizing prospect of nanoparticles to achieve remarkable selectivity for catalytic process. However, achieving electronic/steric control and realizing selectivity regulation in nanocatalysis remains a formidable challenge, as the dynamic nature of metal-ligand interfaces, including dissolution and structural reconstruction, poses significant obstacles. Herein, we disclose carboranyls (CBs) as carbon-bonded global vertexes coordinating ligands (E_{ads.c−Au(111)} = -2.90 eV, E_{ads.BHs−Au(111)} = -0.54 eV) for gold nanoparticles (AuNPs), showcasing their exceptional inherent stabilization capability and the unique core (Au_n)-satellite (CB₂Au⁻) structure of the resulting NPs. Leveraging these distinct features, CB@AuNPs accomplished regio-selective bromination of aromatic feedstocks including chlorobenzene (p:o > 30:1) and phenyl acrylate, a prominent transformation in chemical industry suffered from selectivity issue. Systematic investigations unveiled the advantages of CB@AuNPs, including: 1) the global coordinating capability of ligands in their vicinity, and 2) the presence of inert counterions. These characteristics enable selectivity regulation through counterion manipulation and harness the substituent effect arising from the stabilized catalytic micro-environment at nanoscale. The effective control of regio-selectivity achieved through the global coordination of carboranyls offers valuable insights into expanding current strategy with heterocatalysts via ligand approach.