Photochemical Polar Addition of 1,1-Diphenylethene Using Photosensitive Surfactant in Stable Oil-in-Water Emulsion

An aq NaOH solution of the photosensitive surfactant 1 was mixed with 1,1-diphenylethene 2 to form a stable oil-in-water emulsion and excitation of the emulsion afforded the alcohol 3 in good yield without stirring. The photosensitive surfactant 1 works more efficiently in heterogeneous system (in water) than in homogeneous system (in organic solvent).