Gold Meets Mechanochemistry: Emerging Opportunities in Organometallics and Catalytic Reactions

Mechanochemistry has recently emerged as a practical approach for accessing gold-based organometallic complexes under solvent-minimized or solvent-free conditions. In this personal account, I summarize the developing intersection between gold chemistry and ball-milling, with emphasis on the preparation of Au(I) and Au(III) complexes bearing N-heterocyclic carbene, acyclic diaminocarbene, phosphine, pincer, and cyclometalated ligands. It also discusses the still limited but conceptually important use of gold species in mechanochemical catalysis, including C-H functionalization, multicomponent reactions, alcohol oxidation, and nitroarene reduction. Beyond listing synthetic protocols, this account highlights the operational advantages, current limitations, and unresolved mechanistic questions that define this emerging area. Notable limitations include lack of mechanistic understanding, less informative green metric analysis, unknown reproducibility studies, and scale-up opportunities. The available studies indicate that mechanochemistry can simplify access to selected gold complexes and enable distinctive solid-state catalytic manifolds; however, broader substrate scope, standardized milling parameters, rigorous green metrics, and deeper mechanistic insight will be essential for the field to mature.