A regio- and the diastereoselective ring-expansion reaction of N-acyl aziridine has been described for the synthesis of 4-carboxamide oxazolines using InCl3. A domino Ugi-Joullié/ring expansion reaction of arylphenylazirines, isocyanides, and carboxylic acids led to the target product through N-acylaziridine intermediate in the presence of indium catalyst. The oxazolines were synthesized in moderate to excellent yields with high atom-economy and high bond-forming efficiency under mild reaction conditions.
2‐Cyanobenzaldehye (also called 2‐formylbenzonitrile) and related 2‐acylbenzonitriles belong to a class of bifunctional aromatic compounds that emerged as useful starting materials in developing efficient cascade‐type reactions leading to different heterocyclic compounds. The variety of sometimes unpredictable mechanisms that rise from these structurally simple starting materials renders this class of compounds unique to afford, through divergent cascade reactions, heterocycles like isoindolinones, phthalides (also known with the name of isobenzofuranones), imidates, and in less extent isoindolin‐1‐imine, six‐ and seven‐membered heterocycles, porphyrins, also in asymmetric way exploiting different organocatalytic activation modes. To give a picture, this chemistry can be associated to Goldberg variations which stem from a common motive in a pressing and surprising way. In this Review, emphasis is also given to the synthetic methods for the access to substituted 2‐cyanobenzaldehydes and 2‐acylbenzonitriles which allowed to enlarge the scope of the described cascade reactions.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.