Novel heterocyclic ring-expansion and/or dehydration-hydration reactions of propargylic and allenylic hydroxy γ-lactams in the presence of strong base or Lewis acid

Article abstract of DOI:10.1016/S0040-4020(98)00897-7

Dehydration-hydration products were obtained in good yields by the treatment of propargylich hydroxy γ-lactams with some Lewis acids. Several propargylic and allenylic hydroxy γ-lactams were successfully converted to the corresponding ring-expanded benzazepines in various yields via a tandem decyclization-cyclization process in the presence of (TMS)₂NLi, (TMS)₂NNa, or n-BuLi under reflux conditions in THF.