Ag₂₀ Nanoclusters with Surface Azides as an Easily Functionalized Platform for Diverse Chemical Applications

Abstract Modifying atomically precise nanocluster surfaces while maintaining the cluster core remains a key challenge. Herein, the synthesis, structure, and properties of two targeted Ag₂₀ nanoclusters (NCs) with eight surface azide moieties, [CO₃@Ag₂₀(S^tBu)₁₀(m‐N₃‐C₆H₄COO)₈(DMF)₄] (1‐m) and [CO₃@Ag₂₀(S^tBu)₁₀(p‐N₃‐C₆H₄COO)₈(DMF)₄] (1‐p) are reported, where DMF is N,N‐dimethylformamide. These AgNCs are designed to undergo cluster surface strain‐promoted azide‐alkyne cycloaddition (CS‐SPAAC) reactions, introducing new functionality to the cluster surface. Reactivity is screened using model strained cyclooctynes. Reaction products and parent clusters are characterized by UV–vis, FT‐IR, and NMR spectroscopies. The structure of the parent clusters and presence of surface azides is confirmed by single crystal X‐ray diffraction (SCXRD) analysis. Clusters 1‐m and 1‐p are found to be amenable to CS‐SPAAC reactions with retention of the NC frameworks, opening new routes for efficient modification of AgNC for applications.