Photooxidation studies with perylenediimides in solution, PVC and sol-gel thin films under concentrated sun light

Photooxidation of α-terpinene is performed with ABIPER and N-DODEPER as photosensitizers, both in acetonitrile solutions and immobilized phases (PVC and sol-gel host matrices) by the use of two different irradiation sources, Na lamp and concentrated sun light. The photosensitizers exhibited different activities on the product profile, which were strongly dependent on the irradiation source, period of irradiation and the phase that the sensitizers were placed (solution or immobilized phases). Product analysis results point that in immobilized phases of PVC films 3,6-dioxoheptanal is the major product. In solution and immobilized phase of sol-gel ascaridol is the most abundant product. Superoxide anion radical, forms as reactive intermediate at photoinduced electron transfer process, directs the primary mechanistic step of photooxidations. A secondary mechanistic step is being proposed for the clarification of product formations.