The Lewis acid catalyzed reaction of regioselectively generated silyl enol ethers with vinyl ketones has been explored as an alternative to the Robinson annulation sequence. Alkylation of the trimethylsilyl enol ethers of cyclohexanone, 2-methylcyclohexanone, and 2, 3-dimethylcyclohexanone with ethyl vinyl ketone, 3-penten-2-one, and methyl vinyl ketone ethylene ketal gave a series of 1, bdiketones. Cyclization of the diketones affords 8-dones ...
