ELEKTRONENREICHE HEPTAFULVENE ALS BAUSTEINE VON AZULENEN. 8-METHOXYHEPTAFULVEN

Abstract

Abstract 8-Methoxyheptafulvene (5), the first C-8 monosubstituted electron-rich heptafulvene is synthesized from 1,3,5-cycloheptatriene-7-carbaldehyde dimethyl acetal (4) and lithium diisopropylamide. (8+2) π cycloadditions of (5) are described. Dimethyl azulene-1,2-dicarboxylate (9) and dimethyl 3-methoxyazulene-1,2-dicarboxylate (8) are obtained from the cycloadduct of (5) and dimethyl acetylenedicarboxylate.