Aldehyde decarbonylation has been extensively investigated, primarily using noble-metal catalysts; however, nonprecious-base-metal-catalyzed aldehyde decarbonylation has been hardly reported. We have established an efficient selective aldehyde decarbonylation reaction with a broad substrate scope and functional group tolerance utilizing a heterogeneous Ni(0) nanospecies catalyst supported on CeO2. The high catalytic performance is attributable to the highly dispersed and non-electron-rich Ni(0) nanospecies, which possibly suppress a side reaction producing esters and adsorbed CO-derived inhibition of the catalytic turnover, according to detailed catalyst characterization and kinetic evaluation.

Decarbonylation via oxidative addition has been widely studied as a challenging and beneficial transformation using various carbonyl compounds. To our knowledge, however, diaryl 1,2-diketones have not been subjected to this type of decarbonylation thus far. Herein, we report a versatile 1,2-diketone decarbonylation to afford diaryl ketones via oxidative addition by utilizing a CeO 2 -supported Au−Pd alloy nanoparticle catalyst. According to a thorough catalyst characterization, kinetic evaluation, and control experiment, the high catalytic performance is attributed to the promotion of the reductive elimination as the turnover-limiting step by electron-deficient Pd(0) species due to their strong interaction with CeO 2 and to the suppression of catalyst deactivation by alloying Pd with Au. The present work provides a methodology for activating inert C−C bonds via oxidative addition based on the use of a multifunctional supported nanoparticle catalyst.

This study demonstrated a heterogeneously catalyzed system for decarbonylation of various aryl thioesters to produce thioethers and CO by utilizing CeO2- or hydroxyapatite-supported Ni or Pd nanoparticle catalysts. The Ni catalysts showed high catalytic activity, while the Pd catalysts possessed excellent functional group tolerance.