3-Vinyl oxindole-chromone synthon as a skeletal reconstruction reactant for the synthesis of 2-hydroxy benzoyl pyridones

Abstract

The first example of ring-opening and recyclization reaction of 3-vinyl oxindole-chromones 1 as versatile synthons, which can react with ammonia or primary aliphatic amines as binucleophiles is developed, serving as a fruitful strategy for the eco-friendly and atom-economic synthesis of a new family of skeletally diverse 2-hydroxy benzoyl pyridones 3 with high to excellent yields (70–92%). The advantages of this methodology, including the use of easily available raw materials and the catalyst-free, wide functional group tolerance, and gram-scale synthesis, make the developed methodology a practical way to access important biologically active 2-hydroxy benzoyl pyridone molecules.