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A rapid route to 5,5- and 5,6- bicyclic systems is provided by an 1,3-alkyl-shift process mediated by a hypervalent iodine reagent on aromatics. The structures obtained contain several unsaturations with different behaviors and reactivities. Such diversity allows further elaborations for the rapid formation of compact systems present in a variety of natural products. The potential for further transformations has been demonstrated by performing a double Michael addition. This cyclization process is regio- and stereoselective due to the presence of a former benzylic substituent. Furthermore, an extension of this approach has been accomplished on indole derivatives., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Oxidative 1,2- and 1,3- alkyl shifts mediated by a hypervalent iodine reagent were performed on simple and inexpensive phenol derivatives. These transpositions enable rapid redesign of the main aromatic skeleton to generate good yields of highly functionalized scaffolds containing a prochiral dienone system, a quaternary carbon center connected to as many as four sp(2) centers, and a carbonyl functionality or precursor. An efficient enantioselective version of this process resulting in the formation of a challenging quaternary carbon center is also described. The products represent the central cores of several natural products having important bioactivities. As an illustration of the potential of this method, we describe the rapid synthesis of several functionalized polycyclic systems as well as a formal synthesis of acetylaspidoalbidine, a hexacyclic alkaloid belonging to the Aspidosperma family.

An oxidative Prins-pinacol tandem process mediated by a hypervalent iodine reagent has been developed. This oxidative version of the famous tandem process fits within the concept of "aromatic ring umpolung" and allows the stereoselective transformation of simple phenols into highly elaborated spirocyclic dienone cores containing several quaternary carbon centers. The scope and the limitations of this process, including the study of its stereoselectivity, are described in this article. As a direct application of this stereoselective process, we describe the formal synthesis of (-)-platensimycin, an important antibiotic agent.

An oxidative Wagner-Meerwein transposition involving different functionalities mediated by a hypervalent iodine reagent has been accomplished. The strategy fits within the concept of "aromatic ring umpolung" and allows rapid access to highly functionalized cores.

A concise total synthesis of (+/-)-aspidospermidine has been achieved in twelve steps from inexpensive 4-ethylphenol, based on an oxidative Hosomi-Sakurai reaction via the concept of "aromatic ring umpolung".

An oxidative Friedel-Crafts reaction involving different aromatic compounds mediated by a hypervalent iodine reagent has been performed, using polysubstituted phenols. The strategy fits within the concept of "aromatic ring umpolung", which opens up novel opportunities in chemical synthesis. The reaction takes place in useful yields, and allows rapid access to highly functionalized compounds containing a dienone, a quaternary carbon center, and an aromatic ring. The product's skeleton is present in numerous natural products. As an illustration of the potential of this transformation, total syntheses of compounds belonging to the Amaryllidaceae alkaloids family such as O-methyljoubertiamine, mesembrine, and its natural derivative the dihydro-O-methylsceletenone have been achieved in eight/nine steps. The synthetic route to these molecules features a novel and efficient transformation on the basis of a Fukuyama and Michael-retro-Michael tandem process to produce the required nitrogen-containing ring system.