Radiolytic studies of the reductive cyclization of 2-nitroarylamides: Cyclization via hydroxylamine intermediates
作者:Bridget M. Sykes、Graham J. Atwell、William A. Denny、Charmian J. O'Connor
DOI:10.1002/poc.610080904
日期:1995.9
nitroamides are the corresponding hydroxylamines. Under anaerobic conditions, cyclization via the hydroxylamines was considerably faster (up to 160-fold) than via the corresponding amines under comparable conditions, but was similarly influenced by changes in geometry. Unlike cyclization via the amines, rates of cyclization via the hydroxylamines were sensitive to substitution on the leaving aniline, being
通过辐射还原研究了几种2-硝基芳基酰胺的还原环化作用,研究了取代基对硝基苯环和离去的苯胺的影响以及硝基苯环与离去的苯胺之间的连接性质的变化。还原的化学计量和氮的鉴定-羟基内酰胺和苯胺产物表明,这种还原硝基酰胺的主要初始产物是相应的羟胺。在厌氧条件下,在相当的条件下,通过羟胺的环化比通过相应的胺的环化要快得多(最多160倍),但同样受到几何形状变化的影响。与通过胺的环化不同,通过羟胺的环化速率对离去的苯胺上的取代敏感,被吸电子基团加速。提出羟胺环化中的决定速率的步骤是四面体中间体的分解。