Concurrent primary and secondary deuterium kinetic isotope effects in anilinolysis of O-aryl methyl phosphonochloridothioates
作者:Md. Ehtesham Ul Hoque、Arun Kanti Guha、Chan Kyung Kim、Bon-Su Lee、Hai Whang Lee
DOI:10.1039/b903148k
日期:——
reactions of Y-O-aryl methyl phosphonochloridothioates with substituted anilines (XC6H4NH2) and deuterated anilines (XC6H4ND2) are investigated kinetically in acetonitrile at 55.0 °C. The Hammett and Brønsted plots for substituent (X) variations in the nucleophiles are biphasic concave downwards with a break region between X = H and 4-Cl. The deuterium kinetic isotope effects (DKIEs) are primary normal
动力学研究了Y- O-芳基甲基膦酰氯硫酸酯与取代苯胺(XC 6 H 4 NH 2)和氘代苯胺(XC 6 H 4 ND 2)的亲核取代反应。乙腈在55.0°C下。亲核试剂中取代基(X)变异的哈米特(Hammett)和布朗斯台德(Brønsted)图是双相向下凹的,断裂区域介于X = H和4-Cl之间。氘的动力学同位素效应(DKIEs)是较强亲核试剂(X = 4-MeO,4-Me和H)的主要标准(k H / k D = 1.03-1.30),并且具有非常大的次级逆数(k H / k D = 0.367–0.567)(较弱的亲核试剂(X = 4-Cl,3-Cl和3-NO 2))。交叉相互作用常数是负的(ρ XY(H) = -0.95和ρ XY(d) = -1.11),用于更强的亲核试剂,而正(ρXY(H) = 0.77和ρ XY(d) = 0.21),用于弱亲核体。这些动力学结果表明,该机理从涉