Molecular Crystals and Liquid Crystals, Vol.430, 243-243, 2005
Synthesis and photochromic properties of functional diarylethenes with a [1,3]dithiol-2-one (thione) bridging unit
In designing new photochromic compounds for optical data storage and photo-switching devices, the synthesis of a series of 4,5-diaryl-1,3-dithiol-2-one and 4,5-diaryl-1,3-dithiol-2-thione, which are suitable building blocks for incorporation with fluorophore, is herein reported. Our strategy needs the preliminary preparation of diarylalkynes, obtained by successive Sonogashira-Hagihara coupling-reactions in good yields (63-92%). A combination of these synthetic precursors with diisopropylxanthogen disulfide leads to the corresponding 4,5-diaryl-1,3-dithiol-2-ones under radical conditions with excellent yields (54-70%). The thionation of these compounds is obtained nearly quantitatively with phosphorous pentasulfide.
Keywords:1,2-diarylalkynes;4,5-diaryl-1,3-dithiol-2-one;4,5-diaryl-1,3-dithiol-2-thione;photochromism;synthesis