Condensation Reaction of 5,6-Dihydro-6-methyl-6-piperonyl-2H-pyran-2,4-dione, Ethyl Orthoformate and Substituted Anilines

摘要

Piperonyl methyl ketone was obtained by oxidizing isosafrole with hydrogen peroxide and formic acid. Dianion of ethyl acetoacetate reacted with piperonyl methyl ketone and 5, 6-dihydro-6-methyl-6-piperonyl-2H-pyran-2, 4-dione was prepared, which reacted with substituted anilines in the presence of ethyl orthoformate to obtain 3-anilinomethylene-5, 6- dihydro- 6-methyl-6-piperonyl-2H-pyran-2, 4-diones. Their structures were confirmed by 1HNMR and elemental analysis.