Cis-Trans Photoisomerization and Photooxygenation of 1,2-Diarylcyclopropanes, Salt Effects on the Photoinduced Electron Transfer Reactions

The efficiencies of the 9,10-dicyanoanthracene (DCA)-sensitized cis-trans photoisomerization and photooxygenation of cis- and trans-1,2-bis(4-methoxyphenyl)cyclopropanes (c-CP and t-CP) in CH3CN were remarkably enhanced by the addition of inorganic salts such as LiBF4 and Mg(ClO4)2. The mechanistic implication of the salt effects on these photoreactions was discussed.