Oxidative Photodimerization of Condugated Dienes Catalyzed by 9-Cyanophenanthrene

Abstract

Photoirradiation of a methanol solution containing 2,5-dimethyl-2,4-hexadiene (1) and 9-cyanophenanthrene (9-CP) is known to give oxidative photodimerized product, 2,9-dimethoxy-2,5,5,6,6,9-hexamethyldeca-3,7-diene (2), via photoinduced electron transfer reaction. In this work, we examined about the mechanism of the oxidative photodimerization reaction, improvement of the efficiency, and application to the organic synthesis. As a result, we found that the photodimerization reaction is efficiently catalyzed by 9-CP to give 2, and that various nucleophiles can be introduced to the dimerized products.