Dual Catalysis of Gold Nanoclusters: Photocatalytic Cross‐Dehydrogenative Coupling by Cooperation of Superatomic Core and Molecularly Modified Staples**

Abstract

AbstractThiolate‐protected gold nanoclusters (AuNCs) have attracted significant attention as nano‐catalysts, revealing a superatomic core and gold‐thiolate staples as distinct structural units. Here, we demonstrate the unprecedented dual catalytic activity of thiolate‐protected [Au25(SR)18]− nanoclusters, involving both photosensitized 1O2 generation by the Au13 superatomic core and catalytic carbon‐carbon bond formation facilitated by Au2(SR)3 staples. This synergistic combination of two different catalytic units enables efficient cross‐dehydrogenative coupling of terminal alkynes and tertiary aliphatic amines to afford propargylamines in high yields of up to 93 %. Mixed‐ligand AuNCs bearing both thiolate and alkynyl ligands revealed the intermediacy of the alkynyl‐exchanged AuNCs toward both photosensitization and C−C bond‐forming catalytic cycles. Density functional theory calculations also supported the intermediacy of the alkynyl‐exchanged AuNCs. Thus, the use of ligand‐protected metal nanoclusters has enabled the development of an exceptional multifunctional catalyst, wherein distinct nanocluster components facilitate cooperative photo‐ and chemo‐catalysis.