A C-H bond of electron-rich heterocycles is transformed into a C-N bond in a reaction sequence comprising the formation of heteroaryl(phenyl)iodonium azides and their in situ regioselective fragmentation to heteroaryl azides. A Cu(I) catalyst ensures complete regiocontrol in the fragmentation step and catalyzes the subsequent 1,3-dipolar cycloaddition of the formed azido heterocycles with acetylenes. The heteroaryl azides can also be conveniently reduced to heteroarylamines by aqueous ammonium sulfide. The overall C-H to C-N transformation is a mild and operationally simple one-pot sequential multistep process.

A one-pot two-step method for intermolecular C-H amination of electron-rich heteroarenes and arenes has been developed. The approach is based on a room-temperature copper-catalyzed regioselective reaction of the in situ formed unsymmetrical (hetero)aryl-λ(3)-iodanes with a wide range of primary and secondary aliphatic amines and anilines.

A mild, room-temperature Pd-catalyzed acetoxylation of pyrroles with phenyliodonium acetate is described. The acetoxylation was found to proceed via the initial formation of pyrrolyl(phenyl)iodonium acetates, which were converted to acetoxypyrroles in the presence of Pd(OAc)(2). The acetoxylation could also be carried out as a one-pot sequential procedure without the isolation of the intermediate iodonium salts.

A one-pot two-step method for para-selective C–H amination of carbocyclic arenes comprises the in situ formation of unsymmetrical diaryl-λ3-iodanes followed by their Cu­(I)-catalyzed reaction with a range of N-unprotected amines.

In sharp contrast to hypervalent iodine(III) compounds, the isoelectronic bromine(III) counterparts have been little studied to date. This knowledge gap is mainly attributed to the difficult-to-control reactivity of l 3 -bromanes as well as to their challenging preparation from the highly toxic and corrosive BrF 3 precursor. In this context, we present a straightforward and scalable approach to chelation-stabilized l 3bromanes by anodic oxidation of parent aryl bromides possessing two coordinating hexafluoro-2-hydroxypropanyl substituents. A series of para-substituted l 3 -bromanes with remarkably high redox potentials spanning a range from 1.86 V to 2.60 V vs. Ag/AgNO 3 was synthesized by the electrochemical method. We demonstrate that the intrinsic reactivity of the bench-stable bromine(III) species can be unlocked by addition of a Lewis or a Brønsted acid. The synthetic utility of the l 3 -bromane activation is exemplified by oxidative C À C, C À N, and C À O bond forming reactions.