Atomically precise hydrido gold nanoclusters are extremely rare but interesting due to their potential applications in catalysis. By optimization of molecular precursors, we have prepared an unprecedented N-heterocyclic carbene-stabilized hydrido gold nanocluster, [Au 24 (NHC) 14 Cl 2 H 3 ] 3+ . This cluster comprises a dimer of two Au 12 kernels, each adopting an icosahedral shape with one missing vertex. The two kernels are joined through triangular faces, which are capped with a total of three hydrides. The hydrides are detected by electrospray ionization mass spectrometry and nuclear magnetic resonance spectroscopy, with density functional theory calculations supporting their position bridging the six uncoordinated gold sites. The reactivity of this Au 24 H 3 cluster in the electrocatalytic reduction of CO 2 is demonstrated and benchmarked against related catalysts.

Catalytic iodine in the presence of water acts indirectly as a source of Brønsted acid and, concurrently, generates iodonium ion and hydrogen peroxide, which mediate the final oxidative aromatization step in the multicomponent cyclocondensation of an aromatic amine and two aliphatic aldehyde compounds. The oxidative cycle in this and related iodine‐catalyzed reactions is seldom discussed, generally unoptimized, and rarely investigated in detail. This work establishes that two independent catalytic cycles (H+ and I−/I+) drive such multicomponent cyclocondensation/ oxidation reactions, provided that the oxidant is generated in sufficient concentration to inhibit oxidation of the dihydroquinoline by the intermediate iminium cation. The complementary dual catalytic cycles, when optimized, act in concert to suppress side product formation, which simplifies isolation and purification of the self‐aggregating products, and increases the efficiency and scope of the Wang‐Kozlov multicomponent reaction.

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