As an important class of nitrogen-containing fused heterocyclic compounds, imidazo[1,2-a]pyridines often exhibit significant biological activities, such as analgesic, anticancer, antiosteoporosis, anxiolytic, etc. Using Y(OTf)₃ as a Lewis acid catalyst, a simple and efficient method has been developed for the synthesis of C₃-alkylated imidazo[1,2-a]pyridines through the three-component aza-Friedel–Crafts reaction of imidazo[1,2-a]pyridines, aldehydes, and amines in the normal air atmosphere without the protection of inert gas and special requirements for anhydrous and anaerobic conditions. A series of imidazo[1,2-a]pyridine derivatives were obtained with moderate to good yields, and their structures were confirmed by ¹H NMR, ¹³C NMR, and HRMS. Furthermore, this conversion has the advantages of simple operation, excellent functional group tolerance, high atomic economy, broad substrate scope, and can achieve gram-level reactions. Notably, this methodology may be conveniently applied to the further design and rapid synthesis of potential biologically active imidazo[1,2-a]pyridines with multifunctional groups.

A novel method for the efficient and straightforward synthesis of tetrasubstituted furans is presented, employing a base-catalyzed reaction of α-hydroxy ketones and cyano compounds. The reaction proceeds under relatively mild conditions, utilizes readily available starting materials, and exhibits good functional group tolerance and high yields. Notably, this reaction obviates the need for expensive metal catalysts and introduces crucial functional groups such as amino and cyano moieties. Furthermore, it avoids the prerequisite functionalization of substrates, thereby enhancing atomic economy.

Oxazoles are important five-membered heterocycles that contain both nitrogen and oxygen atoms. Due to their wide range of biological activities, many oxazoles demonstrate potential for extensive application in various fields, including medicinal chemistry. Trifluoromethyl carbinol, an important pharmacophore, contains both trifluoromethyl and hydroxyl groups and is common in molecules with important biological activities. Constructing oxazoles that contain a trifluoromethyl carbinol unit is undoubtedly important and valuable for expanding the chemical space in drug discovery. In this study, a simple and efficient method was developed for the synthesis of oxazoles containing a CF₃-substituted alcohol unit via the tandem cycloisomerization/hydroxyalkylation of N-propargylamides with trifluoropyruvates through a rational Lewis acid catalytic mechanism. This Zn(OTf)₂-catalyzed synthetic protocol is operationally simple and provides a series of oxazoles in moderate to good yields. The protocol demonstrates broad substrate scope, high functional group tolerance, and high atom economy and can achieve gram-level reactions, indicating the strong possibility of its practical application.

An efficient and operationally simple method for the synthesis of α-acyloxy ketones through the readily available 2-methylimidazole-promoted reaction of α-hydroxy ketones and anhydrides is developed. In the reaction, the anhydrides act as both a substrate and a solvent. The new method features good substrate tolerance, mild reaction conditions, readily accessible starting materials, and excellent yields, providing facile and green access to the targets. Importantly, the reaction also avoids the use of reagents with pungent odors, such as pyridine, in traditional esterification, which may promote the development of organocatalysis using nitrogen-containing heterocyclic compounds as catalysts.