作者:Austin Acton、Annette D. Allen、Andrei V. Fedorov、Huda Henry-Riyad、Thomas T. Tidwell
DOI:10.1002/poc.1036
日期:2006.12
constants for hydration of the same substrates: logk2(TEMPO) = 1.64logk(H2O)−5.76 (r = 0.98). These results fit within a previously established correlation of ketene hydration reactivity with aminoxyl radical reactivity, and confirm that the reactivity of TEMPO in additions to ketenes is dominated by the nucleophilic character of the aminoxyl oxygen, with a strong trend of increasing reactivity for more
在4-取代的苯基乙烯酮8(4-RC 6 H 4 CH C O,R = NO 2,CN,Cl )中添加氨基氧基TEMPO(2,2,6,6-四甲基哌啶基氨基氧基,TO·)的动力学研究,H,CH 3,CH 3 O)和3-吡啶基乙烯酮(15)揭示了log k 2(TEMPO)与取代基(包括15的氮杂取代基)的Hammett sigma参数之间的相关性,rho = 1.58(r = 0.94)。使用相同底物的水合速率常数可获得更好的相关性:log k 2(TEMPO)= 1.64log k(H 2 O)-5.76(r = 0.98)。这些结果符合乙烯酮水合反应性与氨氧基自由基反应性的先前建立的相关性,并证实除乙烯酮外,TEMPO的反应性受氨氧基氧的亲核特性支配,对更多亲电子乙烯酮的反应性呈强势增长趋势。版权所有©2006 John Wiley&Sons,Ltd.