Access to Pyrazolidin‐3, 5‐diones through Anodic N–N Bond Formation. Issue 32 (8th July 2016) - Gieshoff, Tile
Abstract: Pyrazolidin‐3, 5‐diones are important motifs in heterocyclic chemistry and are of high interest for pharmaceutical applications. In classic organic synthesis, the hydrazinic moiety is installed through condensation using the corresponding hydrazine building blocks. However, most N, N ′‐diaryl hydrazines are toxic and require upstream preparation owing to their low commercial availability. We present an alternative and sustainable synthetic approach to pyrazolidin‐3, 5‐diones that employs readily accessible dianilides as precursors, which are anodically converted to furnish the N−N bond. The electroconversion is conducted in a simple undivided cell under constant‐current conditions. Abstract : Tying up loose Ns : A novel synthetic approach to pharmacologically relevant heterocycles through anodic N−N bond generation was established. Readily accessible malonic dianilides provide an easy and efficient access to N, N ′‐diarylpyrazolidin‐3, 5‐diones without the need for N, N ′‐diarylhydrazines as building blocks.