Photochromism of Diarylethene Maleimide Derivatives

Abstract

Abstract Diarylmaleimide derivatives having an indole ring, N-cyanomethyl-2-[2-methoxy-1-benzothiophen-3-yl]-3-[2-methyl-1-octadecylindol-3-yl]maleimide or N-cyanomethyl-2-[2-ethoxy-1-benzothiophen-3-yl]-3-[2-methyl-1-octadecylindol-3-yl]maleimide, were synthesized in an attempt to shift the photosensitive wavelength longer such that it becomes longer than 450 nm. The derivatives underwent the photocyclization reaction upon irradiation with 450–550 nm light in hexane solution and the photogenerated closed-ring isomers returned to the initial open-ring isomers upon irradiation with light longer than 600 nm.