The Journal of Organic Chemistry 2018-04-04

Metal-Free Iodine-Catalyzed Oxidation of Ynamides and Diaryl Acetylenes into 1,2-Diketo Compounds

SeungWoo Kim, Tae-Woong Um, Seunghoon Shin

Index: 10.1021/acs.joc.8b00484

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Abstract

Metal-free oxidation of ynamides is described, employing pyridine-N-oxides as oxidants under molecular iodine catalysis. In stark contrast to Brønsted acid catalysis, iodophilic activation of ynamides diverts the reaction manifold into a dioxygenation pathway. This oxidation is very rapid at room temperature with only 2.5 mol % I2. Furthermore, this protocol could be extended to nonactivated alkynes, such as diarylacetylenes, to deliver various benzil derivatives.