Electrochemical Post-Ugi Cyclization for the Synthesis of Highly Functionalized Spirolactams.

The combination of the Ugi reaction and electro-organic synthesis can aid in the creation of novel heterocycles that have not been previously explored. In this study, a new strategy utilizing bis-amides from the Ugi reaction has been developed, which can produce C-S, C-Se, and C-C═O functionalized five-membered spirolactams mediated by electricity under catalyst- and metal-free conditions. Notably, this approach can be applied using a microelectro-flow reactor (μ-EFR) for gram-scale synthesis.

Cell Voltage-Dependent Structural Dichotomy: Electrochemical C-H Acyloxylation and N-Acylation of 2-Indazoles.

A simple and efficient electrochemical method that utilizes modulation of the cell voltage to cause structural alterations in 2-indazole is introduced. This method enables the C-3 acyloxylation of 2-indazole and promotes the transfer of the acyl group from C-3 to N-1, allowing the N-acylation of 2-indazoles. Additionally, the application of the μ-electro flow reactor was demonstrated, showcasing its effectiveness in achieving gram-scale production of within a short residence time.

Merging Electrochemical Synthesis and Post-Ugi Cyclization for the Synthesis of Diverse 4-Imidazolidinones.

Despite the appreciation for electro-organic synthesis, postmulticomponent reaction transformation chemistry rarely exploits this powerful technology. Herein, we explore post-Ugi cyclization reactions using N-centered radical-mediated intramolecular ipso cyclization to synthesize diverse spirocyclic variants of 4-imidazolidinones through the use of electrochemically generated amidyl radicals from the bis-amides of the Ugi adducts. This protocol features an undivided cell setup under constant-current conditions with carbon-platinum electrodes.