Regiospecific Synthesis of Unsubstituted Basic Skeletons of Heterocycles Containing Nitrogen Neighboring an Aromatic Ring by the Reductive Ring Expansion Reaction Using Diisobutylaluminum Hydride

A systematic investigation of reductive ring expansion reaction of oximes with diisobutylaluminum hydride (DIBAH) was performed.The reaction regiospecifically provided a variety of unsubstituted bicyclic heterocycles 3a-3g or tricyclic heterocycles 3h, 3j-3l that contained nitrogen attached to an aromatic ring.