Reverse aromatic-Cope rearrangement

Sol 3. (i) l,l-Divinyl-2-phenylcyclopropane derivative (I) on heating undergoes a vinylcyclopropane rearrangement to give vinylcyclopentene derivative (II). In this reaction one of the vinyl groups of I participates in the reaction and the other is a substituent. The major spirolactam (ID) is formed by a reversible aromatic Cope rearrangement followed by an irreversible ene reaction. In this... 

The reaction with the siloxy derivative 29 is an interesting example because the product 30 is a 1,5-dicarbonyl derivative (Equation (36)).96 1,5-Dicarbonyls are classically prepared by a Michael addition, but the synthesis of 30 by a Michael addition is not possible because it would require addition to the keto form of 1-naphthol. The acetoxy derivative 31 resulted in a different outcome, leading to the direct synthesis of the naphthalene derivative 32 (Equation (37)).96 In this case, the combined C-H activation/Cope rearrangement intermediate was aromatized by elimination of acetic acid before undergoing a reverse Cope rearrangement. 

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