Thermo- and photochromic dyes: Spiro(indolinebenzopyrans). 2—detailed assignment of the1H NMR spectra and structural aspects of the closed form of 1,3,3-trimethylspiro(indoline-2,2′-benzopyrans)
摘要:
报道了一系列 12 种热致变色和光致变色 1,3,3-三甲基螺(二氢吲哚-2,2'-苯并吡喃)染料的质子 NMR 归属。染料分子中的所有质子都是通过同核解耦实验和相关光谱的结合来分配的。吲哚啉偕二甲基的相对立体化学被指定,因此对于 S-差向异构体,发现前 R 甲基在 1.24 ppm 处共振,而对于化合物 1,前 S 甲基出现在 1.37 ppm 处。
properties of a solvent were explored. The spiropyran-azobenzene derivative (SPAB) can be induced to different forms in different miscellaneous solvents accompanied with different color changes and spectral characteristics at the presence of organic base DBU. In a nonpolar or low-polar solvent, SPAB exists in thermostable spiropyran form with yellow color output. While in an aprotic polar solvent, the spiropyran