Treatment of phenols or anilines containing a sulfonyl group in the presence of a hypervalent iodine reagent promotes a formal dearomatizing [2 + 3] cycloaddition reaction on unactivated benzene and naphthalene derivatives. This process occurs via an intramolecular nucleophilic addition to the Wheland species generated during the oxidative activation. Subsequent treatment under acidic conditions readily transforms the tricyclic system into a biaryl via a formal cross-coupling process.

An oxidative ipso-rearrangement mediated by a hypervalent iodine reagent that enables rapid generation of a functionalized dienone system containing a quaternary carbon center connected to several sp(2) centers has been developed. The process occurs through transfer of an aryl group from a silyl segment present on the lateral chain. As an illustration of the potential of this transformation, a total synthesis of sceletenone, a small alkaloid, is described.

Althought there are several reported synthetic routes to strychnine, one of the most widely recognized alkaloids, we report an unexplored route with an oxidative dearomatizing process mediated by hypervalent iodine as the key step. The new syntheses of isostrychnine and strychnine have been achieved from an readily available phenol in nine and ten steps. In addition to the key step, these syntheses involve an aza Michael-ether-enol tandem transformation, two heck type cyclizations, a reductive isomerization, and a double reductive amination in cascade leading to the alkaloid main core.

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A chemoselective and environmentally benign oxidation of benzylic amines into aldehydes mediated by a hypervalent iodine reagent has been developed. This mild oxidative version of the Polonovski process may be selectively carried out in the presence of several functionalities including a free alcohol and provides new synthetic opportunities as a masked aldehyde segment.