The hydrolysis products of cis-diamminedichloroplatinum(II) 5. The anation kinetics of cis-Pt(X)(NH3)2(OH2)+ (XCl, OH) with glycine, monohydrogen malonate and chloride
作者:Sian E. Miller、Donald A. House
DOI:10.1016/s0020-1693(00)90384-0
日期:1991.9
mol −1 ; k cy (25.0 °C, pH=4.3, I =1.0 M)=1.03×10 −5 s −1 , Δ H ≠ =88.9 kJ mol −1 , Δ S ≠ =−42 J K −1 mol −1 . The rate ( k 3 , s −1 ) of the chloride release from cis -PtCl(OH)(NH 3 ) 2 to give cis -Pt(OH)NH 3 ) 2 (OH 2 ) + and rate of chloride uptake (k −3 , M −1 s −1 ) have been measured at pH=7.4. Kinetic parameters are k 3 =2.39×10 −5 s −1 (25.0 °C, pH=7.4, I =1.0 M) Δ H ≠ =82.4 kJ mol −1 , Δ S ≠
摘要用甘氨酸(Nu = gly在pH = 7.4时)或丙二酸氢钠(Nu)对顺式-PtCl(NH 3)2(OH 2)+进行阴离子分光光度法测定的速率常数k obs(s -1) = Hmal-在pH = 4.3时)可以由等式k obs = ko + k Nu [Nu]表示,其中ko是不依赖亲核试剂浓度但取决于pH的水解速率常数,并且k Nu是亲核试剂依赖性路径。 。在Nu = Hmal-的情况下,ko〜0,第一步是单齿配位,由于闭环,第二步(k cy)亲核试剂独立路径。在Nu = gly的情况下,闭环反应足够快以至于与配位同步出现,并且ko是在pH = 7.4时顺式-PtCl(OH)(NH 3)2的碱水解速率常数。与阴离子相关的动力学参数为k Hmal(25.0°C,pH = 4.3,I = 1.0 M)= 9。90×10 -4 M -1 s -1,ΔH≠= 74.8 kJ mol -1,ΔS≠=