A multi-responsive diarylethene system based on the structure transformation by chemical and light stimuli

A novel diarylethene with a Schiff base unit was successfully synthesized and its multi-responsive photochromism could be effectively modulated by chemical and light stimuli. By the stimulation of sodium hydroxide, the absorption maximum of its closed-ring isomer showed extraordinarily large redshift of 134 nm, accompanied with a notable color change from purple to green. Subsequent irradiation with 420 nm visible light further caused a dramatic change in its color from green to cyan due to the formation of the benzoxazole moiety. Moreover, the deprotonated open-ring isomer exhibited typical photochromism via the diarylethene intermediate with a benzoxazole unit.