2‑Oxo-Driven N₂ Elimination Induced Decarbonylative Cyclization Reaction in Benzotriazoles to 6‑Aminophenanthridines

An efficient functional group induced strategy for the synthesis of 6-aminophenanthridines (6AP) has been developed as a result of an in situ generated novel system “CO–CH­(N₁N₂)”. This reaction presents a new mode of N₂ extrusion in benzotriazoles that later result in decarbonylative cyclization to 6AP. This method offers an easier protocol for the synthesis of 6AP from readily available inexpensive substrates

Amino Catalytic Oxidative Thioesterification Approach to α‑Ketothioesters

An efficient metal-free method for the synthesis of α-ketothioesters is described for the first time. This reaction features the ability of pyrrolidine to fine-tune the reaction between 2-oxoaldehyde and thiols through iminium to the desired product in moderate to good yields. As an advantage, no external oxidants or metal catalysts are required in our method. Reactions performed under modified conditions lead to an apparent balance in reactivity of secondary amine and thiols toward 2-oxoaldehydes

I₂/Aqueous TBHP-Catalyzed Coupling of Amides with Methylarenes/Aldehydes/Alcohols: Metal-Free Synthesis of Imides

We present a metal-free method for the synthesis of imides by the direct coupling of NH-amides with methylarenes under iodine/aqueous TBHP conditions. The optimized conditions worked very well with benzaldehydes and benzyl alcohol and furnished the corresponding imides in good to excellent yields. A series of control and radical scavenger experiments were also performed, which suggested the involvement of radical pathways. The labeling experiment in the presence of ¹⁸O-labeled H₂O suggested water as a source of oxygen in the imides

Metal-Free Oxidative Amidation of 2‑Oxoaldehydes: A Facile Access to α‑Ketoamides

A novel and efficient method for the synthesis of α-ketoamides, employing a dimethyl sulfoxide (DMSO)-promoted oxidative amidation reaction between 2-oxoaldehydes and amines under metal-free conditions is presented. Furthermore, mechanistic studies supported an iminium ion-based intermediate as a central feature of reaction wherein C₁-oxygen atom of α-ketoamides is finally derived from DMSO