Electronic Effects of Substituents on Indole Nitrogen on the Photochromic Properties of Indolylfulgides
作者:Soichi Uchida、Yasushi Yokoyama、Jitsuo Kiji、Tamon Okano、Hitoshi Kitamura
DOI:10.1246/bcsj.68.2961
日期:1995.10
N-p-tolylsulfonylindolylfulgide by Stobbe condensation was unsuccessful because hydrolysis of the Stobbe-condensation product eliminated the sulfonyl moiety to give, after several steps, the N-unsubstituted fulgide. Pd(II)-catalyzed carbonylation of 2-butyne-1,4-diol derivative bearing the N-p-tolylsulfonylindole, however, afforded the desired N-p-tolylsulfonylindolylfulgide. A comparison of absorption
通过 Stobbe 缩合合成 Np-甲苯磺酰基吲哚基富酸酐的尝试没有成功,因为 Stobbe 缩合产物的水解消除了磺酰基部分,在几个步骤后得到 N-未取代的富酸酐。然而,Pd(II) 催化的带有 Np-tolylsulfonylindole 的 2-butyne-1,4-diol 衍生物的羰基化得到了所需的 Np-tolylsulfonylindolyfulgide。将这些富酸酐的吸收光谱和光致变色特性与已知的 N-甲基吲哚基富酸酐的吸收光谱和光致变色特性进行比较,得出以下结果。氮上的吸电子取代基(i)缩短了有色形式的吸收最大值,(ii)抑制了热 E-Z 异构化,以及(iii)扩大了光致变色反应的量子产率。