Unusual Effects of Acetate Ion on Photosensitized Oxygenation of Naphthalene Derivatives via Electron Transfer

Abstract
The oxygenation of 2-methylnaphthalene photosensitized by 9,10-dicyanoanthracene in an O2-saturated acetonitrile gave phthalic acid and 4-methylphthalic acid in the presence of Et4NOAc or KOAc/18-crown-6, but different products in the presence of Et4NBF4 and KClO4 and without a salt. The photosensitized ring oxygenation also occurred with naphthalene and 2,3-dimethylnaphthalene.