Multi-state molecular switches based on dithienylperfluorocyclopentene and imidazo [4,5-f] [1,10] phenanthroline

Two novel diarylethene derivatives containing imidazo [4,5-f] [1,10] phenanthroline have been efficiently synthesized. These molecules are sensitive to both light and chemical stimuli. Under sequential alternating UV-vis light irradiation and alkali/acid treatment, distinct differences in NMR, UV-vis, and fluorescent spectra were observed. Taking advantage of the variations in visible absorption and fluorescence, a reversible four-state molecular switch with two optical outputs was realized by a single molecule. (c) 2006 Elsevier Ltd. All rights reserved.