Hypervalent iodine-mediated oxygenative phenol dearomatization reactions

Both λ3- and λ5-iodanes have proven to be useful reagents in the oxygenative dearomatization of phenols, and exploitations of their chemistry in the conception of both substrate- and reagent-controlled asymmetric variants of such a transformation of great value for natural product synthesis have shown evident signs of success. Moreover, the use of stabilized IBX (i.e., SIBX) in our methodology for O-demethylation of 2-methoxyphenols, which relies on the same key oxygenating dearomatization event, is reported here to be much more efficacious than that of IBX itself in the chemoselective one-step conversion of homovanillyl alcohol into hydroxytyrosol, and bergenin into norbergenin.

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