论文部分内容阅读
苯并冠醚由于苯环上环流效应引起的各向异性内部磁场使醚环区的谱线能很好地分辨。便于谱线的指认,同时也可以提供更多有关空间结构的信息,因而引起了人们广泛的兴趣。它们的~(18)C NMR谱由于化学位移值大,谱线结构简单更受到化学工作者的重视。有关这类化合物的数据,文献上虽有报导,但不系统。为了便于应用NMR这一有力工具来研究各种冠醚的不同化学性能,我们记取了不同大小环的苯并-12-冠-4(Ⅰ),苯并-15-冠-
The anisotropic internal magnetic field caused by the benzene ring crowning effect makes the ether ring region well resolved. Which is convenient for the identification of spectral lines and can also provide more information about the spatial structure. Therefore, it has aroused widespread interest. Their 18 C NMR spectra are highly valued by chemists because of their large chemical shift and simple spectral structure. The data on these compounds are reported in the literature, but not systematically. In order to facilitate the use of NMR as a powerful tool to study the different chemical properties of various crown ethers, we have taken into account the different sizes of benzo-12-crown-4 (Ⅰ), benzo-15-crown-