The Substituent Effect. XIII. Solvolysis of 1-(7-Substituted 2-Fluorenyl)ethyl Chlorides and Alkaline Hydrolysis of Ethyl 7-Substituted 2-Fluorenecarboxylates
作者:Yuho Tsuno、Yoshihiko Tairaka、Masami Sawada、Takahiro Fujii、Yasuhide Yukawa
DOI:10.1246/bcsj.51.601
日期:1978.2
Two sets of rate constants for (i) solvolysis of 1-(7-substituted 2-fluorenyl)ethyl chlorides in both 90 and 80% aqueous acetone and (ii) alkaline hydrolysis of ethyl 7-substituted 2-fluorenecarboxylates in 85% aq EtOH have been determined. Both substituent effects could be correlated excellently with the LArSR relationship; the resulting r+ values (0.82 and 0.47, respectively) were comparable with
(i) 1-(7-取代 2-芴基)乙基氯在 90% 和 80% 丙酮水溶液中的溶剂分解和 (ii) 7-取代 2-芴羧酸乙酯在 85% 乙醇水溶液中的碱水解的两组速率常数已经确定。两种取代基效应都与 LArSR 关系密切相关;在相同条件下,所得 r+ 值(分别为 0.82 和 0.47)与相应联苯基系统中的 r+ 值相当。ρπ+ 值的比较清楚地表明芴基比联苯基系统更有效地传递π电子效应(1:0.75)。这可以归因于后一个 pi 系统中的扭曲因素。发现 Pi 效应传输的衰减是独立于反应的介入 pi 系统的特征:1。