Normal, Leveled, and Enhanced Steric Effects in Alkoxyamines Carrying a β-Phosphorylated Nitroxyl Fragment
作者:Gérard Audran、Raphael Bikanga、Paul Brémond、Jean-Patrick Joly、Sylvain R. A. Marque、Paulin Nkolo
DOI:10.1021/acs.joc.7b00541
日期:2017.6.2
The design of new R1R2NOR3 alkoxyamines for various applications relies on the accurate prediction of two kinetic parameters, the C–ON bond homolysis rate constant (kd) and its re-formation rate constant (kc). Relationships to describe the steric and polar effects of the R1R2NO fragment ruling kd have been developed. For all cyclic nitroxyl fragments, the steric effect is described as the sum of the
用于各种应用的新R 1 R 2 NOR 3烷氧基胺的设计依赖于两个动力学参数的准确预测,即C-ON键均溶速率常数(k d)和其重整速率常数(k c)。已经开发出描述R 1 R 2 NO片段规则k d的空间和极性效应的关系。对于所有环状亚硝酰基片段,空间效应被描述为R 1和R 2的体积庞大之和分组(即正常的空间效应),而对于非环状的硝酰片段(除一种情况),假定水平的空间效应。在这项工作中,我们表明正常的空间效应也适用于非环状硝酰基片段,并且在一种情况下,还观察到了增强的空间效应,即实验k d > 5倍于预测值。