Silicon-induced ene-type reaction in the thermal conversion of enolates to beta-silyl enones with molecular dioxygen

Org Lett. 2008 May 15;10(10):1913-6. doi: 10.1021/ol800007v. Epub 2008 Apr 24.

Abstract

Reaction of alkyl, acetoxy, and silyl enol ethers of 3-(organosilyl)cyclohexanone with molecular dioxygen in toluene at 110 degrees C produced the corresponding conjugated enones in yields up to 88% yield. The reaction of the same type failed on replacement of the silyl group at the C-3 position with an isopropyl group. These results indicate the existence of an unprecedented silicon-induced ene-type reaction. Its reaction mechanism, generality, limitations, and exceptions are discussed.