Chemical Selectivities Disguised by Mass Diffusion. VIII. Influence of pH-gradients on the product distribution in mixing-disguised azo coupling reactions. 9th Communication on the selectivity of chemical processes
作者:Hasan Belevi、John R. Bourne、Paul Rys
DOI:10.1002/hlca.19810640540
日期:1981.7.22
In mixing-disguised azo coupling reactions the protons which are released during the electrophilic substitution steps cause a pH-gradient in the reaction zone. Since, owing to the acid-base pre-equilibria, these pH-gradients also determine the local concentrations of the reactants in the reaction zone, they also have an influence on the measured product distribution of such fast reactions. In the present
在混合伪装的偶氮偶合反应中,在亲电取代步骤中释放的质子在反应区中引起pH梯度。由于由于酸碱的预平衡,这些pH梯度也决定了反应区中反应物的局部浓度,因此它们也影响了这种快速反应的产物分布。在目前的工作中,通过实验测量了1-萘酚与4-磺基苯基重氮离子偶氮偶合的产物分布,并将其结果与我们先前开发的混合反应模型预测的分布进行了比较[1]。此外,提供了一些存在等选择性点的实验证据,在这些点上,初始pH值的变化对产物分布没有影响。