Cycloaddition of the anion derived from homophthalic anhydride to cis,cisoid,cis-tricyclo[6.3.0.02,6]undeca-4,9-diene-3,11- dione. Aromatization as a driving force for intramolecular sigmatropic hydrogen transfer

Abstract

Reaction of the anion derived from homophthalic anhydride with cis,cisoid,cis-tricyclo[6.3.0.02,6]undeca-4,9-diene-3,11- dione proceeds via initial Diels–Alder cycloaddition followed by intramolecular dyotropic hydrogen migration with concomitant aromatization; the structure of the reaction product (4)(formed in 42% yield) was established via single-crystal X-ray structural analysis.