must be revised. The n.m.r. spectra for intermediates in the syntheses show a steric effect for the t-butyl group and indicate the presence of geometric and rotational isomers of the sterically hindered benzimidates, which were rearranged to give the carboxydiphenylamin derivatives. The t-butyl group was eliminated in all attempts to prepare 9-t-butylaminoacridine. Acridine 9-aminoacridine, and a number
由相应的2-羧基
二苯胺(
二苯胺-2-
羧酸)合成了2-s-丁基-,2-叔丁基-和2,7-二叔丁基-9-
氨基ac啶和其他a啶。他们的1 H nmr光谱表明必须对9-
氨基ac啶进行更早的修饰。合成中中间体的nmr光谱显示了叔丁基的空间效应,表明存在空间受阻的苯甲二酸盐的几何和旋转异构体,将其重新排列以得到羧基
二苯胺衍
生物。在所有制备9-叔丁基
氨基ac啶的尝试中都消除了叔丁基。preferential啶9-
氨基ac啶和许多其他衍
生物无法通过多种大型烷基化剂在位置10上烷基化,因为发生了优先消除。