Electron transfer reactions (ETR) oftert-butyl perbenzoates with dimethyl sulfide: the rates controlled by translational entropy
作者:Sung Soo Kim、Sang Hak Lim
DOI:10.1002/poc.1099
日期:2006.10
Various tert-butyl perbenzoates were prepared according to the known methods. The mixtures of tert-butyl perbenzoate and dimethyl sulfide underwent thermolysis at several temperatures (T °C: 80, 90, 100, and 110). The rates of consumption of the peresters (kobs) were obtained from ln C0/Ct = kobs × t where C0 and Ct are the concentration of the perester at time 0 and t, respectively. For example: The
根据已知方法制备了各种过苯甲酸叔丁酯。过苯甲酸叔丁酯和二甲基硫醚的混合物在数个温度(T°C:80、90、100和110)下进行热解。从ln C 0 / C t = k obs × t获得过酸酯的消耗率(k obs),其中C 0和C t分别是时间0和t处的过酸酯浓度。例如:过氧化物的减少满足拟一级动力学,并确定了k obs 。k坎。和k ET是从k obs = k Hom获得的。 + ķ ET [CH 3 SCH 3 ]其中,[CH 3 SCH 3 ] / [过酸酯]> 10. ķ ET和其相对速率从积产生ķ OBS反对[CH 3 SCH 3 ]。针对σ和σ+绘制了Hammett相关性,其中σ的相关性比σ+更好。哈米特ρ可以认为选择性与温度无关而保持恒定。该现象与反应性/选择性原理不一致。微分活化熵随取代基常数σ线性增加,斜率为2.63,而微分焓的相似斜率显示出较低的0.892