Synthesis, crystal structure and optoelectronic properties of a new unsymmetrical photochromic diarylethene

摘要

A new unsymmetrical photochromic diarylethene. 1-(2-methyl-5-phenyl-3-thienyl)-2-[2-methyl-5-(3-trifluoromethylphenyl) -3-thienyl]perfluorocyclopentene (la), was synthesized and its structure was determined by single-crystal X-ray diffraction analysis. Its optical and electrochemical properties. including photochromic reactivity both in solution and in the solid state (PMMA film and the single-crystalline phase), fluorescence and electrochemical properties were investigated in detail. The compound showed excellent photochromism even in the single-crystalline phase by photo-irradiation. In acetonitrile, the open-ring isomer of diarylethene 1 exhibited relatively strong fluorescence at 470 nm when excited at 300 nm, and its emission intensity decreased along with the photochromism upon irradiation with 313 nm light. Its closed-ring isomer showed almost no fluorescence. The electrochemical properties of diarylethene were investigated by performing cyclic voltammetry experiment and its HOMO and LUMO energy level were calculated. (C) 2007 Elsevier B.V. All rights reserved.