Metal-Free Redox Transformations for C–C and C–N Bond Construction

This manuscript is dedicated to Prof. V. Snieckus, a larger-than-life inspirational chemist, on the occasion of his 80th birthday

Abstract

In this Account, the authors retrace their development of remote functionalisation reactions relying on photoredox catalysis. Inextricably connected to this is their discovery of small molecule organocatalysts that behave as formal reductive activators of diazonium salts, while requiring no promotion by visible light. This ultimately paved the way for the development of an unusual class of reactions in which the catalyst is also the nucleophile.

Key words

photocatalyst - diazonium salt - redox - hydrazine - 1,5-hydrogen transfer

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