The polysubstituted tropylium ions having cyclopropyl or t-butyl groups at the ring positions with the least steric hindrance, i.e. 1,3- and 1,4-dicyclopropyltropylium, 1,3- and 1,4-di-t-butyltropylium, 1,3,-5-tricyclopropyl- and 1,3,5-tri-t-butyltropylium and 1,2,4,6-tetracyclopropyltropylium ions (4), were synthesized, and their properties were compared with the known monosubstituted and unsubstituted
在具有最小空间位阻的环位置具有环丙基或叔丁基的多取代的托鎓离子,即1,3-和1,4-二环丙基托鎓,1,3-和1,4-二-叔丁基托鎓,1,合成了 3,-5-
三环丙基-和 1,3,5-三-叔丁基托鎓离子和 1,2,4,6-四环丙基托鎓离子 (4),并将它们的性质与已知的单取代和未取代阳离子进行了比较。环丙基衍
生物的 1H 和 13C NMR 谱和叔丁基衍
生物的 13C NMR 谱在连续取代后显示出七元环信号的逐渐上场位移。因此,对于叔丁基衍
生物,发现 pKR+ 值在引入每种取代基后线性增加;对于环丙基衍
生物,