APPLICATIONS OF THE PHOTOCHEMICAL-REACTION OF IODOHETEROCYCLIC DERIVATIVES WITH AROMATIC-COMPOUNDS IN THE SYNTHESIS OF NEW SINGLET OXYGEN SENSITIZERS

Study of the photochemical coupling reaction between 2-iodo-5-nitrothiophene and indolyl derivatives indicated that the coupling reaction occurs on the C-2 position of indole to give products showing absorptions in the visible region. The photochemical reaction between iodoheterocyclic derivatives and heterocyclic allylic acetates gave the corresponding coupling products that were used as starting materials in the synthesis of polyhydroxylated compounds through reaction of the corresponding allylic alcohols with osmium tetroxide. The same reaction on 1,2-dithienylethylene or 1-(2-furyl)-2-(2-thienyl) ethylene derivatives failed. Both indolyl derivatives and polyhydroxylated compounds synthesized in this work proved to be singlet oxygen sensitizers in the photo-oxidation of trans-alpha,alpha'-dimethylstilbene.