Effect of Two Electron-Donating Substituents on Photochromism of Aryl Fulgide, 2-(2,6-Dimethyl-3,5-substituted benzylidene)-3-isopropylidenesuccinic Anhydride

Article abstract of DOI:10.1246/bcsj.65.2352

Two electron-donating substituents (e. g. p-diethylaminostyryl) were introduced to an aryl structure of fulgide and photochromic performance was investigated.It was found that the strong electron-donating ability of the substituents caused a significant red shift of the colored form to the near-infrared region (λ_max; 633 nm), resulting in a high molecular extinction coefficient (ε_max; 24300 mol^-1 cm^-1).Furthermore, rapid reactions of both coloration and discoloration were observed; the quantum yields (φ_EC and φ_CE) were 0.65 and 0.052, respectively.