Photochemical formation of strained cage compounds and their acid-catalysed reversion as a preliminary model for light energy conversion

Abstract

On irradiation, some Diels–Alder adducts derived from cyclic dienes and dienones gave, quantitatively, strained pentacyclic C₁₂, C₁₁, and C₁₀ cage compounds, which rapidly and completely reverted to the starting compounds with the evolution of heat (18·0–23·5 kcal/mol) when treated with an acid; the C₁₁ system was found to be the most promising for the reversible storage of light energy.