ABSTRACT
Allenes are frequently used as building blocks for the synthesis of cyclic compounds by inter-and intramolecular photochemical cyclization reactions with ketones, thiones, enones, and related compounds. Most of the reactions, however, proceed between the ground state of the allenes and the excited state of the other reactants. Over the past 40 years, many photochemical reactions of allenes have been reported, and theoretical studies of the excited states have been conducted.
