Magnesium methoxide‐induced chemiluminescent decomposition of bicyclic dioxetanes bearing a 2′‐alkoxy‐2‐hydroxy‐1,1′‐binaphthyl‐7‐yl moiety

Bicyclic dioxetanes 2a–c bearing a 2′‐alkoxy‐2‐hydroxy‐1,1′‐binaphthyl‐7‐yl moiety were effectively synthesized and their base‐induced chemiluminescent decomposition was investigated by the use of alkaline metal (Na + and K + ) or Mg 2+ alkoxide in MeOH. When 2a–c were treated with tetrabutylammonium fluoride (TBAF) in dimethyl sulfoxide (DMSO) as a reference system, they showed chemiluminescence as a flash of orange light (maximum wavelength λ max CL  = 573–577 nm) with efficiency Φ CL  = 6–8 × 10 –2 . On the other hand, for an alkaline metal (Na + or K + ) alkoxide/MeOH system, 2a–c decomposed slowly to emit a glow of chemiluminescence, the spectra of which were shifted slightly toward red from the TBAF/DMSO system, and Φ CL (= 1.4–2.3 × 10 –3 ) was considerably decreased. In addition, Mg(OMe) 2 was found to play a characteristic role as a base for the chemiluminescent decomposition of 2a–c through coordination to the intermediary oxidoaryl‐substituted dioxetanes 13. Thus, Mg 2+ increased Φ CL to more than twice those with Na + or K + , while it shifted λ max CL considerably toward blue (λ max CL  = 550–566 nm). Copyright © 2012 John Wiley & Sons, Ltd.