Useful 1,2-dioxygenated dienes: syntheses and Diels–Alder reactions en route to substituted 2-naphthols and phenols

Abstract

The design and synthesis of novel heteroatom functionalized dienes competent to expand the chemical space of the Diels–Alder cycloaddition reaction to prepare valuable yet challenging architectures continues to be highly desirable in organic synthesis. Here, we present a practical method to synthesize 1,2-dioxygenated dienes via a Pd-catalyzed alkenylation reaction of vinylene carbonate with readily available vinyl triflates. The diene synthesis protocol tolerates various functional groups and substitution types, affording diverse dienes including ones containing natural product fragments. Empowered by the unique 1,2-carbonated motif, these dienes can smoothly undergo a tandem Diels–Alder cycloaddition/decarboxylative aromatization/oxidation reaction, allowing the concise syntheses of 2-naphthol architectures with ease. In addition, the preparation of substituted phenols and natural product derivatives is viable employing alkynes as the dienophiles, and excellent regioselectivity is observed when unsymmetrical alkynes are used.