Unification of Solvolysis Mechanisisms

在C-13 NMR信号，诱导同位素氧取代O-16/O-18的分裂，成功地利用定量确定的程度，O-18混乱内的三个氧的磺酸盐部分。将该方法应用于对甲苯磺酸芳烷基酯溶剂解反应的返回过程的研究。金刚烷基溶剂解酶的（1-F）值与溶剂的依赖性与α-叔丁基苄基酮的（1-F）值一致。因此，离子对返回对基于2-金刚烷基Y_的α-叔丁基苄基溶剂解的溶剂效应分析结果几乎没有影响<OTs>。尽管芳基辅助和苄基溶剂解具有亲核限制性质，但溶剂效应对这些溶剂解的影响不能用使用金刚烷基Y_的Winstein-Grunwald方程给出单一的线性相关性，<OTs>而是对各种二元水溶剂系列表现出特征分散性。benzy过渡态反应中心电荷的发展 ...更多信息 LIC K_C碳正离子过程通过与芳基的有效π重叠而高度离域，这可能导致与脂肪族定域2-金刚烷基阳离子相比在反应中心的高度取向的特定溶剂化的显著损失。对甲氧基新酚溶剂分解的溶剂极性标度Y_<DELTA>与Y_<OTs>相结合，对含有不同程度的π-离域相互作用和初始碳正离子电荷的苄基芳烷基甲苯磺酸酯的溶剂分解反应显示出广泛的适用性：log（k/k_o）= aY_<OTs>+ bY_<DELTA>。该方程可以很高的精度应用于各种系列的芳基辅助溶剂分解反应，表明了k_c-k_机理的连续谱<DELTA>。苄基k_c溶剂分解反应也可用Y_c和Y_c的线性组合处理<OTs><DELTA>。修正的aY_<OTs>和bY_（<DELTA>包括cN_<OTs>项）方程也被推广到烷基和芳烷基甲苯磺酸酯的亲核溶剂解反应中，但效果有限，表明亲核溶剂的参与没有精确的加和性。少

The splitting in the C-13 NMR signals, induced by isotopic oxygen substitution O-16/O-18, was utilized successfully to determine quantitatively the extent of O-18 scrambling within three oxygens in the sulfonate moiety. This method was applied to the investigation of return process in the solvolysis of various arylalkyl tosylates. The solvent dependency of (1-F) value in adamantyl solvolyses shows in good accordance with that of alpha-t-butylbenzyl one. Accordingly the ion-pair return scarcely affects the result of the solvent effect analysis of alpha-t-butyl benzyl solvolysis based on 2-adamantyl Y_<OTs>.Despite the nucleophilically limiting nature of aryl-assisted and benzylic solvolyses, the solvent effect on these solvolyses failed to give a single linear correlation with the Winstein-Grunwald Equation, using the adamantyl Y_<OTs> but showed characteristic dispersion for various binary aqueous solvent series. Developing charge at the reaction center in the transition state of benzy … More lic k_c carbocationic process is highly delocalized through effective pi-overlapping with aryl group, and this may cause a significant loss of the highly oriented specific solvation at the reaction center in comparison with that for aliphatic localized 2-adamantyl cation. The solvent polarity scale Y_<DELTA> based on p-methoxyneophyl solvolysis combined with the Y_<OTs> has shown a wide applicability to the solvolyses of benzylic arylalkyl tosylates involving varying degree of pi-delocalization interaction with the incipient carbocation charge ; log (k/k_o) = aY_<OTs> + bY_<DELTA>. The equation can be applied to various series of aryl-assisted solvolyses in an extremely high precision, suggesting a continuous spectrum of k_c-k_<DELTA> mechanisms. Benzylic k_c solvolyses can also be treated with linear combination of Y_<OTs> and Y_<DELTA>. Application of revised equation, aY_<OTs> and bY_<DELTA> including cN_<OTs> term has also been extended to the nucleophilic solvolyses of alkyl and arylalkyl tosylates, with limited success, indicating no precise additivity for the nucleophilic solvent involvement. Less