Synthesis of Pyridines and Pyrazines Using an Intramolecular Hydroamination‐Based Reaction Sequence

Abstract

A management issue! Various pyridines and pyrazines can be efficiently accessed from simple acyclic precursors using an intramolecular hydroamination/isomerization/aromatization sequence (see scheme). p-Toluenesulfonic acid (2 mol %) is used to catalyze this novel alkyne annulation, in which the oxime group allows for a subsequent redox-neutral aromatization step to occur.