Effects of doping in 25-atom bimetallic nanocluster catalysts for carbon–carbon coupling reaction of iodoanisole and phenylacetylene

A trio of thiolate-protected atomically precise gold nanoclusters, [Au_(23)(S-c-C_6H_(11))_(16)]~–, Au24(SCH_2pH~tBu)_(20)and [Au_(25)(SCH_2CH_2pH)_~(18)]~–, are utilized as catalysts for 4-nitrophenol(4-NP) reduction to 4-aminophenol(4-AP).Despite nearly identical sizes(~1 nm), the three nanoclusters possess distinctly different atomic packing structures and surface ligand binding modes, which contribute to different catalytic performance. The [Au_(23)(Sc-C_6H_(11))_(16)]~–nanocluster shows the highest activity with a kinetic rate constant of 0.0370 s~(-1), which is higher than those of Au24(SCH_2pH~tBu)_(20)(0.0090 s~(-1)) and [Au_(25)(SCH_2CH_2pH)_~(18)]~–(0.0242 s~(-1)). Such a trio of gold nanoclusters indicate that the atomic packing mode and electronic structure play a crucial role in determining their catalytic performance.

Mechanistic insights from atomically precise gold nanocluster-catalyzed reduction of 4-nitrophenol