An electrochemical C–H amination process enables sustainable unified access to the heterocyclic classes of pyrrolidines and piperidines.

The dual function of the N À Fb ond as an effective oxidant and subsequent nitrogen source in intramolecular aliphatic C À Hfunctionalization reactions is explored. Copper catalysis is demonstrated to exercise full regio-and chemoselectivity control, whicho pens new synthetic avenues to nitrogenated heterocycles with predictable ring sizes.F or the first time,auniform catalysis manifold has been identified for the construction of both pyrrolidine and piperidine cores.The individual steps of this new copper oxidation catalysis were elucidated by control experiments and computational studies, clarifying the singularity of the NÀFf unction and characterizing the catalytic cycle to be based on acopper(I/II) manifold.

Iodine catalysis was developed for aliphatic fluorination through light‐promoted homolytic C−H bond cleavage. The intermediary formation of amidyl radicals enables selective C−H functionalization via carbon‐centered radicals. For the subsequent C−F bond formation, previous methods have typically been limited by a requirement for electrophilic fluorine reagents. We here demonstrate that the intermediary instalment of a carbon–iodine bond sets the stage for an umpolung, thereby establishing an unprecedented nucleophilic fluorination pathway.

Iodine catalysis was developed for aliphatic fluorination through light‐promoted homolytic C−H bond cleavage. The intermediary formation of amidyl radicals enables selective C−H functionalization via carbon‐centered radicals. For the subsequent C−F bond formation, previous methods have typically been limited by a requirement for electrophilic fluorine reagents. We here demonstrate that the intermediary instalment of a carbon–iodine bond sets the stage for an umpolung, thereby establishing an unprecedented nucleophilic fluorination pathway.

We have recently developed a method for the synthesis of pyrrolidines and piperidines via intramolecular C–H amination of N -fluoride amides using [Tp x CuL] complexes as precatalysts [Tp x = tris(pyrazolyl)borate ligand and L = THF or CH 3 CN]. Herein, we report mechanistic studies on this transformation, which includes the isolation and structural characterization of a fluorinated copper(II) complex, [(Tp iPr2 OH)CuF] [Tp iPr = hydrotris(3,5-diisopropylpyrazolyl)borate], pertinent to the mechanistic pathway. The effects of the nature of the Tp x ligand in the copper catalyst as well as of the halide in the N–X amides employed as reactants have been investigated both from experimental and computational perspectives.

Die Bifunktionalitätd er N-F-Bindung als wirksames Oxidationsmittel und nachfolgende Stickstoffquelle in intramolekularen aliphatischen C-H-Funktionalisierungen wird untersucht. Dabei wird gezeigt, dass eine Kupferkatalyse eine vollständige Regio-und Chemoselektivitätskontrolle ermçglicht, wodurchn eue Synthesewege zu stickstoffhaltigen Heterozyklen mit vorhersagbarer Ringgrçße geebnet werden. Fürd en Aufbau von Pyrrolidin-und Piperidinringen wird erstmals ein einheitlicher Katalysezyklus identifiziert. Die einzelnen Schritte dieser neuen Kupferoxidationskatalyse werden durch Kontrollexperimente und Computerstudien aufgeklärt, um die Einzigartigkeit der N-F-Funktion zu belegen und die Katalyse als einen Kupfer(I/II)-Zyklus zu charakterisieren.

Just like a horse capturing a pawn to win its position in a chess game, nitrogen‐centered radical selectivity for hydrogen atom abstraction allows for a novel directed aliphatic C−H fluorination methodology. As described by D. Bafaluy, Z. Georgieva, and K. Muñiz in their Communication on page 14241, the unique and outstanding performance of halogen catalysis enables the use of simple fluoride as the fluorine source in a homogeneous approach to 1,3‐ and 1,4‐fluoroamines.

No abstract