model for understanding the bell-shaped pH-profiles. Analysis of the pressure and substituent effects on the reaction kinetics suggest that the k2 pathway is (i) more probable than the kinetically indistinguishable k3 pathway, and (ii) presumably mechanistically similar to the induced cleavage of the peroxide O−O bond postulated for cytochrome P450 enzymes. The redox titration of 1 by IrIV and electrochemical
停流Fe的氧化的动力学研究III -TAML催化剂,[ ˚F ∈1,2-X 2 c ^ 6 ħ 2 -4,5-(NCO
CME 2 NCO)2
CME 2 }(OH 2)] - (1),通过
水中的t -BuOOH和H 2 O 2提供Fe IV物种有助于阐明1与一级氧化剂的相互作用机理。在pH 6.0-13.8和17-45°C下收集的取代Fe III -TAMLs的数据已证实该反应是一阶反应1和过氧化物。有效二阶速率常数k I的钟形pH分布在10.5-12.5的pH范围内具有最大值,具体取决于1和所选过氧化物的性质。“酸性”部分是由diaqua形式的1的去质子决定的,因此吸电子基团将反应性的较低pH极限移向中性pH,尽管速率常数k I变化不大。将k I分解为各个固有速率常数k 1([FeL(OH 2)2 ] - + ROOH),k 2([FEL(OH 2)OH)] 2- + ROOH),ķ 3([FEL(OH