Synthesis of a new class of tetronic acid derivatives: a one-pot three-component condensation reaction between isoquinoline or pyridine and dialkyl acetylenedicarboxylate with tetronic acid

Reaction of the zwitterions generated from isoquinoline or pyridine and dialkyl acetylenedicarboxylate with tetronic acid leads to 1,2-dihydroisoquinoline or 1,2-dihydropyridine tetronic acid derivatives without using any catalyst or activation at room temperature.