Efficient Solvent-Free Synthesis of Indolizines Using CuBr Catalyst from Pyridine, Acetophenone, and Electron-Deficient Alkenes

Herein, we have developed a new approach for the synthesis of indolizine via Cu-catalyzed reaction of pyridine, acetophenone, and nitroolefin under mild conditions in high yields. This reaction involved the formation of C-N and C-C bonds and new indolizine compounds with high stereoselectivity and excellent functional group tolerance.

Synthesis of N-, O-, and S-heterocycles from aryl/alkyl alkynyl aldehydes

In the field of heterocyclic synthesis, alkynyl aldehydes serve as privileged reagents for cyclization reactions with other organic compounds to construct a broad spectrum of N-, O-, and S-heterocycles. Due to the immense application of heterocyclic molecules in pharmaceuticals, natural products, and material chemistry, the synthesis of such scaffolds has received wide attention. The transformations occurred under metal-catalyzed, metal-free-promoted, and visible-light-mediated systems. The present review article highlights the progress made in this field over the past two decades.

Lewis Acid-Promoted Three-Component Cyclization for the Construction of Functionalized Oxazoles

A simple and efficient synthetic strategy from amides, ynals, and sodium sulfinates via a Lewis acid-promoted three-component reaction has been reported. Thus, a broad range of various aryl (not alkyl)-substituted oxazoles could be synthesized via the formation of C-N, C-O, and C-S bonds in a one-pot process. In addition, this reaction possesses other unique advantages, such as transition metal-free catalysis, high step economy, good functional group tolerance, and good regioselectivity.

Electrochemical diselenylation of indolizines via intermolecular C-Se formation with 2-methylpyridines, α-bromoketones and diselenides

An efficient electrochemical system for the construction of diselenytlated indolizines from available pyridines, ketones and diselenides under undivided electrolytic conditions was developed. No external oxidants and transition-metal catalysts are needed for achieving this three-component tandem reaction realizing C-C, C-N and C-Se bond formations.