A chemo- and regioselective Pd(0)-catalyzed three-component spiroannulation.

A chemo- and regioselective Pd(0)-catalyzed spiroannulation has been successfully developed. The key feature of this method is the use of readily available 1,2-dihaloarenes, alkynes and 2-naphthols for the rapid assembly of spirocarbocyclic molecules. Mechanistic studies revealed that this domino reaction proceeded through a cascade of oxidative addition to Pd(0), alkyne migratory insertion, and 2-naphthol-facilitated dearomatizing [4+1] spiroannulation.