Structural Aspects of 1,2-Dioxetanes Active toward Intramolecular Charge-Transfer-Induced Chemiluminescent Decomposition

Simple 1,2-dioxetanes decompose thermally to produce mainly triplet-excited carbonyl fragments, whereas 1,2-dioxetanes bearing an aromatic electron donor display intramolecular charge-transfer-induced decomposition with accompanying effective emission of light. This type of 1,2-dioxetanes has been extensively studied with a view to understanding the mechanisms of bioluminescence and chemiluminescence and applying them to modern biochemical and biomedical analyses. In this account, recent developments of dioxetane-based chemiluminescent substrates are described from the viewpoint of relationships between the structure of dioxetanes and the properties of chemiluminescence, namely, chemiluminescent efficiency, singlet-chemiexcitation efficiency, color, and the rate of chemiluminescent decomposition.