Perfluoroalkylation of Triarylamines by EDA Complexes and Ulterior Sensitized [6]-Electrocyclization to Perfluoroalkylated Endo-Carbazoles. Mechanistic and Photophysical Studies

Blue LEDs-irradiation of a mixture of N,N,N',N'-tetramethylethylenediamine (TMEDA) and perfluoroalkyl iodides (R-F-I) - Electron Donor Acceptor (EDA)-complex - in the presence of triphenylamines (TPAs) in an aqueous solvent mixture afforded mono-perfluoroalkylated triphenylamines (R-F-TPA) in good yields. These R-F-TPA were further subjected to acetone-sensitized [6 pi]-electrocyclization at 315 nm-irradiation affording exclusively perfluoroalkylated endo-carbazole derivatives (R-F-CBz) in quantitative yields. Mechanistic studies and photophysical properties of products are studied.