Synthesis and photochromic reactivity of macromolecules incorporating four dithienylethene units

Two macrocycles bearing four dithienylethene units were synthesized. Upon irradiation of the macrocycles and with ultraviolet light, only one or two photo-induced cyclization reaction occurs. Each isomers were isolated and analyzed by 1H NMR spectrum. The quantum yield of and are 0.58 and 0.64, respectively. The high value is due to the presence of enforced antiparallel conformation in the macrocycles and .