Synthesis, Crystal Structure, Solid Photochromic Properties and Light‐induced Radical Behavior of Bis{3‐[alkyl/(p‐alkoxyphenyl)]‐3‐hydroxyindan‐1‐on‐2‐ylidene} Derivatives

Abstract

AbstractA series of new bis{3‐[alkyl/(p‐alkoxyphenyl)]‐3‐hydroxyindan‐1‐on‐2‐ylidene} derivatives 1–6 were prepared and characterized fully by 1H NMR, IR, MS and elemental analysis data. The structures of compounds 1, 5 and 6 were confirmed by the single‐crystal X‐ray diffraction. The photochromic and light‐induced properties were examined by means of UV‐Vis and electron spin resonance (ESR) spectroscopy methods, respectively. The results show that all the title compounds in this work simultaneously exhibit photochromism in solid state and generate stable free radicals under irradiation with a 200 W high pressure Hg‐lamp. Structure‐property relationship within these photochromic compounds was discussed in the context of their molecular structures and intra‐molecular interactions.