Studies On The Synthesis Of Polysubstituted Pyridines And Oxazoles Using Enaminones As The Scaffolds

Unsaturated enaminones compounds are kinds of important structural unit, which are widely used as the key scaffolds for the synthesis of a variety of N-heteroarenes such as pyridines, pyrroles, indoles, quinolines etc.Pyridines represent a privileged class of heterocyclic compounds, and emerge in many naturally occurring bioactive molecules. Indeed, pyridines are the important basic raw materials in medicine and chemical industry. Therefore, the synthesis of pyridine rings has already become the research hotspot in the field of organic synthesis. In this dissertation, we described a novel route for the synthesis of polysubstituted pyridine derivatives from N-propargyl enaminones via a series of cascade reactions, using N-heteroarenes or formamides as nucleophile reagents.Oxazoles are widespread in bioactive natural products. In particular, the molecules isolated from marine organisms display a wide of biological activities. Subsequently,oxazoles are widely used as the substrate for the synthesis of complex natural products. This methodology is a high efficent way to access functionalized polysubstituted oxazoles from enaminones via iodine-mediated C-O bone formation/dehydrogenative annulation reaction.