Electrochemical Cyclization of Alkene with Bisnucleophile to Assemble Piperazine/1,4-Diazepane Scaffolds

Piperazine and homopiperazine skeletons are widely recognized as privileged scaffolds for the construction of pharmaceuticals. Nevertheless, the facile synthesis of diverse carbon-substituted piperazine derivatives from readily available, structurally simple feedstock chemicals remains a formidable synthetic challenge. Herein, we disclose a modular electrochemical strategy for the efficient synthesis of functionalized piperazine and 1,4-diazepane derivatives. This protocol employs inexpensive and commercially available alkenes as the starting materials. Crucially, the well-designed reaction sequence including anodic oxidation and nucleophilic attack effectively forged the C-N bond formation twice, ultimately delivering the target heterocyclic products. By employing electrons as traceless oxidants, the protocol is endowed with operational simplicity, mild reaction conditions, and broad functional group tolerance.