Turing-Type Catalytic 2 <scp>D</scp> -Metal Nanomesh Inside Silica-Bilayer for Multicomponent Reaction Control

Although Turing-like ordering is common at macroscopic scales, its realization in metal nanostructures has been hindered by the intrinsic tendency of metals toward symmetric growth and coarsening. Here, we report the first synthesis of a few-nanometer-scale Turing-type pattern in a metal catalyst, achieved through a Nano-Molecular Dual confinement (NanoMolD) strategy. A bilayer hollow silica nanoscaffold with a ∼2 nm internal cavity provides spatial confinement, while in situ self-assembly of a surfactant-palladium ion complex modulates precursor diffusion and surface deposition. This synergistic confinement produces an ultrathin two-dimensional palladium nanomesh with periodic, curved "Turing" stripes encased in silica. The 2D nanomesh features a high density of under-coordinated Pd atoms and twin boundaries, forming a unique catalytic architecture. As a result, this catalyst enables multicomponent carbonylative coupling reactions (e.g., Sonogashira, Suzuki-Miyaura, Buchwald-Hartwig, and alcohol coupling) with exceptional efficiency, affording ≥95-99% yields from aryl iodides and appreciable activity with bromides and chlorides. Furthermore, the confined nanomesh facilitates a one-pot sequential semihydrogenation of the intermediate alkynyl ketone to an α, β-unsaturated ketone (chalcone) by simply introducing H₂, with tunable selectivity governed by the nanostructure. The Turing-type nanomesh is stable, fully recyclable, and demonstrates how nanoscale reaction-diffusion structuring can unlock new capabilities in heterogeneous catalysis.