Gold and Bronsted Acid Catalyzed Hydride Shift onto Allenes: Divergence in Product Selectivity

摘要

A series of allenyl ethers can be transformed into various fused or spiro tetrahydrofurans and tetrahydropyrans following a hydride shift/cydization sequence. A divergence in product selectivity, which depends on the nature of the catalyst used (Au(l) complex or Bronsted acid), was observed.