Michael-Aldol Double Elimination Cascade to Make Pyridines: Use of Chromone for the Synthesis of Indolizines

A domino Michael-aldol double elimination route to indolizines having two different acyl groups at the C5 and C7 positions is described where chromone is employed as a two-carbon unit for the synthesis of a pyridine moiety for the first time. Various analogues were readily accessed in good yields under metal-free and eco-friendly conditions. Further manipulation of the resulting products allowed entry to novel indolizine-heterocycle adducts, which are difficult to access by other methods.

Automated summary

A domino Michael-aldol double elimination route was utilized to synthesize indolizines with two different acyl groups at the C5 and C7 positions, using chromone as a two-carbon unit for the first time. Various analogues were easily obtained in good yields under metal-free and eco-friendly conditions. Manipulation of the resulting products led to the synthesis of novel indolizine-heterocycle adducts that are not easily accessible by other methods.