Syntheses and Photochromic Studies of Dithienylethene-Containing Imidazolium Derivatives and Their Reactivity towards Nucleophiles

摘要

A series of dithienylethene-containing imidazolium salts with various substituents on the 2-position of the imidazolium ring has been synthesized. The photochromic properties of these compounds have been studied, and the closed forms are found to be solvatochromic due to the donor–acceptor interaction with the solvent molecules. The closed form of the imidazolium salt shows a much higher affinity towards nucleophiles over the open form of the salt. A reaction pathway has been proposed to account for this reactivity difference based on the structure–property relationship, and the possible structure of the reaction product is discussed.