Pd-Catalyzed Cross-Coupling Reactions with Carbonyls: Application in a Very Efficient Synthesis of 4-Aryltetrahydropyridines

Scaffold builders: Readily available 4‐piperidones are directly employed in a very efficient Pd‐catalyzed synthesis of 4‐aryltetrahydropyridines, which are important scaffolds in medicinal chemistry. The actual coupling partner, a tosylhydrazone, is generated in situ from the piperidone and tosylhydrazine. The reaction can be applied to other ketones and aldehydes, providing polysubstituted olefins directly from carbonyls by a very simple and efficient procedure (see scheme).