Synthesis of a Photochromic Fused 2H-Chromene Capable of Generating a Single Coloured Species
作者:Céu M. Sousa、João Pina、João Seixas de Melo、Jerome Berthet、Stephanie Delbaere、Paulo J. Coelho
DOI:10.1002/ejoc.201101702
日期:2012.3
A new photochromic fused 2H-chromene that has a dehydropyran bridge between the pyran double bond and the benzene ring was prepared. Unlike standard 2H-chromenes that give rise to two coloured species (one short- and one long-lived) under UV irradiation, flash photolysis studies on this particular 2H-chromene show that the opening of the pyran ring led to the formation of a single, coloured, open species
制备了一种在吡喃双键和苯环之间具有脱氢吡喃桥的新型光致变色稠合2H-色烯。与在紫外线照射下产生两种有色物质(一种短寿命和一种长寿命)的标准 2H-色烯不同,对这种特殊 2H-色烯的闪光光解研究表明,吡喃环的打开导致形成单个,有色,开放的物种,可在 <1 毫秒内漂白成无色的初始形式。这种融合的 2H-色烯的设计避免了不受欢迎的长寿命、transoid-trans、有色、开放形式的形成;因此,根据单指数动力学,颜色褪色非常快,没有在 2H-色烯中常见的任何残留颜色的持久性。4-[(乙氧羰基)甲基]-2H-色烯的酸处理导致内酯的形成。