Hypervalent Iodine Reagent‐Mediated Selective Vinyl C−H Amidation of 4‐Alkoxystyrenes with Diarylsulfonimides for Preparation of Enamides

Hypervalent Iodine(III)-Mediated Umpolung Dialkoxylation of N-Substituted Indoles

Herein, we report dialkoxylation of N-substituted indoles through a hypervalent iodine-mediated umpolung strategy, affording trans-2,3-dimethoxyindolines with up to 95% yield. In addition, C5-selective bromination of 2,3-dialkoxyindoline via NBS-mediated rearomatization was achieved. DFT calculation of the sequence of electrophilic addition and nucleophilic substitution pathway of N-substituted indoles has also been investigated.

Hypervalent Iodine Reagent-Promoted Hofmann-Type Rearrangement/Carboxylation of Primary Amides

A novel transformation of primary amides to secondary amides promoted by hypervalent iodine reagents was developed. The hypervalent iodine reagent-mediated Hofmann-type rearrangement generated an isocyanate intermediate, which was subsequently trapped by an in situ generated carboxylic acid from the hypervalent iodine reagent to provide the corresponding secondary amides. This method provided a facile and efficient route for the synthesis of secondary amides from primary amides and also revealed novel reactivities of hypervalent iodine reagents.

Oxidative cross-dehydrogenative coupling between iodoarenes and acylanilides for C–N bond formation under metal-free conditions

A metal-free oxidative cross-dehydrogenative coupling between iodoarenes and acylanilides was developed. It gave highly para-selectivie C–N coupling products with the retention of iodine atom which enables further transformations.