Photoredox Reactions in Water-in-Oil Microemulsions. The Functions of Amphiphilic Viologens in Charge Separation and Electron Transfer across a Water-Oil Boundary

Article abstract of DOI:10.1021/j150663a036

The photosensitized reduction of the series of dialkyl-4,4'-bipyridinium salts, C_nV²⁺, is examined in water-in-oil microemulsions, by using Ru(bpy)3²⁺ as sensitizer and (NH4)3EDTA as electron donor.With the amphiphilic electron acceptors (n=8-18) the water-in-oil microemulsion media affect the charge separation of the initial encounter cage complex, 3+...C_nV^+.>, and stabilize the photoproducts, C_nV^+. and Ru(bpy)3³⁺, against the recombination process.Consequently, enhanced quantum yields for C_nV^+. formation are observed under continuous illumination.