The label scrambling within the ethylene chain of the final acetolysis products was determined for a series of α-D2 labeled 2-arylethyl tosylates by using proton NMR spectroscopy and the kΔ⁄ks values were derived from the scrambling ratios. For both buffered and unbuffered acetolysis runs log (kΔ⁄ks) were not correlated linearly with σ° or σ+. Application of the LArSR Eq. results in linear correlations
通过使用质子 NMR 光谱,确定了一系列 α-D2 标记的甲
苯磺酸 2-芳基
乙酯在最终乙酰化产物的
乙烯链内的标记扰乱,kΔ⁄ks 值来自扰乱比。对于缓冲和未缓冲的乙酰化运行,日志 (kΔ⁄ks) 与 σ° 或 σ+ 不呈线性相关。
LArSR 方程的应用。导致具有出色精度的线性相关性,对于无缓冲运行,log (kΔ⁄ks)=−3.70 (σ°+0.63Δ\barσR+)+0.152 和 log (kΔ⁄ks)=−3.97 (σ°+0.60Δ\barσR+) )−0.207 用于缓冲运行。芳基辅助途径的 ρΔ 和 rΔ 值是根据上述表观值估算的,这是基于 ks 途径的小 ρs 值的合理假设。