A zwitterionic 1,2,3-triazolium amidate was designed for use as an effective modular hydrogen-atom transfer catalyst for photoredox C−H functionalization. This zwitterionic amidate is stable yet amenable to single-electron oxidation for generating a highly reactive amidyl radical. In cooperation with an Ir-based visible-light photoredox catalyst, the optimal catalyst enables the efficient direct alkylation of the C−H bonds of various nitrogen-or oxygen-containing organic compounds.

The development of an intermolecular and enantioselective aza-Wacker reaction is described. Using indoles as the N-source, a selection of alkenols as the coupling partner enables selective β-hydride elimination towards the alcohol. This strategy preserves the newly formed stereocenter by preventing the formation of traditionally observed enamine products. Allylic and homoallylic alcohols with a variety of functional groups are compatible with the reaction in high enantioselectivity. Isotopic-labeling experiments support a syn amino-palladation mechanism for this new class of aza-Wacker reactions.

The catalytic asymmetric phase-transfer cyanation of alkylideneindolenines, generated in situ from sulfonylalkylindoles, was developed. In the presence of sodium cyanide and a catalytic amount of chiral 1,2,3-triazolium salt, a series of sulfonylalkylindoles can be transformed into the corresponding chiral 3-sec-alkylindoles with good-to-high levels of efficiency and enantioselectivity.

A catalytic asymmetric alkylation of fully substituted enolates with racemic, non-activated secondary alkyl halides is described. The chiral 1,2,3-triazolium ion enables excellent diastereo- and enantiocontrol via enantiofacial discrimination of prochiral enolates and kinetic resolution of secondary halides.