Photochromism of dihydroindolizines. Part II-Synthesis and photophysical properties of new photochromic IR-sensitive photoswitchable substituted fluorene-9′-styrylquinolinedihydroindolizines
作者:Saleh Abdel-Mgeed Ahmed
DOI:10.1002/poc.509
日期:2002.7
Twenty-nine new photochromic 2,4,7-substituted fluorene-9′-styrylquinolinedihydroindolizines (DHIs) 4a–χ were prepared in 45–75% yield via nucleophilic addition of 4-styrylquinolines 2a–k to substituted spirocyclopropenes 1a–c. The absorption maxima (λmax) of the colored betaines 3a–χ were detected by flash photolysis measurements. All betaines 3a–χ showed two absorption maxima, one in the visible
通过向取代的螺环丙烯1a-c中亲核加成4-苯乙烯基喹啉2a-k,以45-75%的收率制备了29种新的2,4,7-光致变色的2,9,4-芴基苯乙烯基喹啉二氢吲哚吲哚(DHIs)4a-χ。彩色甜菜碱3a–χ的吸收最大值(λmax)通过快速光解法检测。所有甜菜碱3a-χ均显示出两个吸收最大值,一个在可见光区域(450-525 nm),另一个在红外光区域(825-950 nm)。在低温(77 K)下,通过FT-UV-Vis-Near-IR光谱记录了甜菜碱3a-χ的吸收光谱。甜菜碱3a–χ快速环化过程的动力学通过毫秒快速光解法研究了DHIs4a -χ对DHI的影响,发现发生在毫秒范围内(二氯甲烷溶液中35-310毫秒,甲醇溶液中50-425毫秒)。使用激光闪光光解法测量的瞬态寿命(约1毫秒)归因于(Z)到(E)-甜菜碱3的转化。在吸收最大值(λ大溶剂化变色效果最大)和半衰期的大幅增加(吨1/2与be