A new LiI-promoted O- to N-alkyl migration has been developed for the conversion of O-alkylated 2-hydroxy pyridines, quinolines, and pyrimidines to the corresponding N-alkylated heterocycles in good to excellent yields (57-99%). This method serves as an efficient means for the preparation of N-benzyl pyridones, quinolones, and pyrimidones.

An efficient and inexpensive LiI-promoted O- to N-alkyl migration of 2-benzyloxy-, 2-allyloxy-, and 2-propargyloxypyridines and heterocycles is reported. The reaction produces the corresponding N-alkyl 2-pyridones and analogues under green, solvent-free conditions in good to excellent yields (30 examples, 20-97% yield). This method has been shown to be intermolecular and requires heat and lithium cation to occur.

Pyridine derivatives R 0380Synthesis of Substituted N-Benzyl Pyridones via an O-to N-Alkyl Migration. -Heating of 2-benzyloxypyridines with LiI allows a new and efficient access to N-benzylated pyridones. N-benzylated pyrimidones, pyrazinones, and quinolones are also available. -(LANNI, E. L.; BOSSCHER, M. A.; OOMS, B. D.; SHANDRO, C. A.; ELLSWORTH, B. A.; ANDERSON*, C. E.; J. Org. Chem. 73 (2008) 16, 6425-6428; Dep. Chem. Biochem., Calvin Coll., Grand Rapids, MI 49546, USA; Eng.) -Jannicke 01-148