Oxidation of Silyl Enol Ethers by Using IBX and IBX⋅N-Oxide Complexes: A Mild and Selective Reaction for the Synthesis of Enones

α,β-Unsaturated carbonyl compounds can be prepared by the oxidation of trimethylsilyl enol ethers with IBX (1) or IBX⋅MPO (2). A diverse set of carbonyl compounds can be dehydrogenated with ease by using this method. Trimethylsilyl enol ethers such as 4, which are formed in situ by the addition of an organometallic species to an enone, can be dehydrogenated with 1 or 2 to give a functionalized enone (e.g. 3→5). IBX = iodoxybenzoic acid; MPO = 4-methoxypyridine-N-oxide.