Synthesis of δ-hetaryl-α,α-dicarbonylalkadienes and a study of their isomerization

Article abstract of DOI:10.1007/BF02321384

The reaction of β-hetarylacrolein and β-hetaryl-α-methylacroleins with esters of acetoacetic and malonic acids was studied. The structures of the products obtained were established using ¹H and ¹³C NMR and UV spectroscopy. (E) and (Z) isomers of α,α-dicarbonylalkadienes, their mixtures with the corresponding 2H-pyrans or exclusively 2H-pyrans are formed depending on the substitution in the starting aldehyde and the ester used. 6-Methyl- and 3,6-dimethyl-5-carbalkoxy-2-(2-pyridyl)pyrans are converted upon heating to substituted 2-(pyrilidene)pyrans. 1997 Plenum Publishing Corporation.