Synthesis of Spiro[4.5]ecanes by Au(I)-Catalyzed Vinylogous Conia Ene Reaction

Au(I) catalysed vinylogous Conia ene reaction was developed to construct the densely functionalized spiro[4.5]-deca-1,6-diene-8-ones from easily available 4-alkyne tethered cyclohex-2-enones. 17 substrates with multiple substitutes on the cyclohex-2-enone ring were explored to afford the corresponding spiro[4.5]in 52-81 % yields. This reaction features mild conditions, wide substrate scope and atom economic characters. Au(I) catalysed vinylogous Conia ene reaction was developed to construct the spiro[4.5]-deca-1,6-diene-8-ones. The spirocyclization reaction was applied to rapidly construct the tetracyclic skeleton of ganocin C.image