Terminal Olefins to Linear α,β-Unsaturated Ketones: Pd(Ⅱ)/ Hypervalent Iodine Co-catalyzed Wacker Oxidation-Dehydrogenation

摘要

Development of a mild (35 ℃, no Bronsted acids) tandem Wacker oxidation-dehydrogen-ation of terminal olefins was accomplished using palladium(Ⅱ) and hypervalent iodine co-catalysis. The reaction affords linear aryl and alkyl α,β-unsaturated ketones directly from readily available terminal olefins in good yields (average 75% per step) with excellent functional group tolerance and chemo- and stereo-selectivities. The hypervalent iodine co-catalyst was found to be critical for dehydrogenation but was not effective as a stoichiometric oxidant.