Stable and Recyclable Copper Nanoclusters with Exposed Active Sites for Broad-Scope Protosilylation in Open Air.

Despite recent advances in cluster-based catalysis for organic synthesis, the substrate scope of reactions catalyzed by metal nanoclusters is typically not superior to previously established catalytic systems. Herein, we develop new atomically precise copper nanoclusters for protosilylation, with scope expanding to alkenes and simple enynes that were not suitable for prior synthetic methodologies with traditional copper complexes. The involvement of a second copper center in the metal kernel during the migratory insertion step is thought to be responsible for the expanded scope. In addition, the reaction is highly compatible with water and can be carried out in open air rather than under inert gas protection. Mechanistic studies suggest that the cluster-catalyzed protosilylation proceeds in the absence of silyl radicals. The current findings demonstrate the potential of using metal nanoclusters for practical and sustainable chemical synthesis.