Thermal rearrangements of benzobicyclononatrienes (1,4-propeno-1,4-dihydronaphthalenes) to benzobarbaralanes; intramolecular Diels–Alder rather than intramolecular ene reactions
Abstract
The rearrangement of (1) to (2) involves the sequence (1)→(4)→(7)→(8)→(2) rather than the intramolecular ene process (1; arrows) earlier proposed; other examples of this process and the walk rearrangement of type (4)→(7) are described.