The cathodic cleavage of the 4-nitrobenzyloxycarbonyl group from amine derivatives in aprotic conditions
作者:Hernani L. S. Maia、Maria-Jose Medeiros、Maria-Irene Montenegro、Derek Pletcher
DOI:10.1039/p29880000409
日期:——
The cathodic cleavage of the 4-nitrobenzyloxycarbonyl group from the urethane derivatives of four amines, two primary and two secondary, in dimethylformamide is reported. It is shown by cyclic voltammetry that the derivatives are reduced in several steps. The first occurs at about –1.1 V vs. s.c.e. and on the timescale of cyclic voltammetry is a reversible 1 e process. On the timescale of several minutes
据报道,在二甲基甲酰胺中从四个胺(两个伯和两个仲)的氨基甲酸酯衍生物中4-硝基苄氧基羰基的阴极裂解。通过循环伏安法表明,衍生物在几个步骤中被还原。第一次出现在大约–1.1 V vs。在循环伏安法的时间尺度上,这是一个可逆的1 e过程。然而,在几分钟的时间尺度上,阴离子自由基不稳定并且发生4-硝基苄基羰基的裂解。库仑法然后表明该还原为2e过程,并且游离胺的分离产率超过80%。因此,在质子惰性条件下于–1.2 V还原似乎是去除4-硝基苄氧基羰基的简单方法的基础,这扩大了在大分子合成中使用该保护基的范围。还讨论了质子给体对氨基甲酸酯衍生物还原的影响。