Oxy-pyridinium Ylides Mediated 1,4-Pyridyl/Aryl Translocation.

Molecular rearrangement via carbene transfer is a powerful tool to access molecular diversity. Herein, we describe an efficient approach to selective pyridyl/aryl relocation via a rhodium-catalyzed aminoarylation of diazo compounds, providing a promising strategy to access -pyridyl N-alkylated pyridone scaffolds in a single operation. This reaction features the novel reactivity of oxy-pyridinium ylide, rhodium-associated five-membered transition state, and 1,4-pyridyl/aryl relocation. A computational study discloses the initial oxy-pyridinium ylide formation, keto-enol tautomerization, and 1,4-pyridyl migration to complete the whole rearrangement.