Synthesis of N‐Aryl α–Ketoamides, α–Ketoesters, α–Ketothioesters and Their Applications in Quinoxalinone Preparation

Sulfur-Promoted Access to 3-Arylquinoxalin-2-ones by Oxidative Coupling of o-Phenylenediamines with Arylacetates

We disclose the synthesis of 3-arylquinoxalin-2-ones from o-phenylenediamines and readily available arylacetates. The method harnesses the selective oxidative property of elemental sulfur in the presence of amine base catalyst and DMSO. The reactions are operationally simple and tolerate a wide range of functional groups.

Microwave-assisted chemoselective transamidation of secondary amides by selective N-C(O) bond cleavage under catalyst, additive and solvent-free conditions

A microwave-assisted, highly chemoselective protocol has been developed for the transamidation of tert-butyloxycarbonyl (Boc) activated secondary carboxamides with amines. Under non-conventional microwave techniques, the reactions were achieved under catalyst, additive, promoter and solvent-free conditions. The transamidation of a structurally diverse set of amides and amines was accomplished in good to excellent yields. The salient features of the developed methodology include a simple operation, broad substrate scope, functional group tolerance, practicality, and the scalability.