A Time-Resolved Electron Paramagnetic Resonance Investigation of the Spin Exchange and Chemical Interactions of Reactive Free Radicals with Isotopically Symmetric (<sup>14</sup>N−X−<sup>14</sup>N) and Isotopically Asymmetric (<sup>14</sup>N−X−<sup>15</sup>N) Nitroxyl Biradicals
作者:Elena Sartori、Igor V. Khudyakov、Xuegong Lei、Nicholas J. Turro
DOI:10.1021/ja0687670
日期:2007.6.1
(14N-X-15N), were employed as probes of the spin exchange and chemical interactions between r and the nitroxyl biradicals. The interaction of r# with the asymmetric ortho-nitroxyl biradical (14N-O-15N), which exists in a condition of strong spin exchange, proved to be particularly informative. In this case, spin polarized (14N-O-15N)# (product of spin exchange with r#) and two polarized monoradicals (r14N-O-15N)#
通过时间分辨电子顺磁共振 (TR-EPR) 研究了反应性自由基 (r) 与稳定的单硝酰自由基 (N) 和双硝酰自由基 (NXN) 之间的相互作用。反应性自旋极化自由基 (r#) 具有非玻尔兹曼自旋态,是通过苄基二甲基单缩酮或(2,4,6-三甲基苯甲酰基)二苯基氧化膦的激光闪光光解产生的(上标 # 符号表示电子自旋极化)。同位素对称的硝酰基双自由基 (14N-X-14N) 和同位素不对称的硝酰基双自由基(一个硝酰基带有 15N,另一个带有 14N(14N-X-15N))被用作 r 之间的自旋交换和化学相互作用的探针和硝酰基双自由基。r#与不对称邻硝酰基双自由基(14N-O-15N)的相互作用,它存在于强烈的自旋交换条件下,被证明是特别有用的。在这种情况下,自旋极化的 (14N-O-15N)#(与 r# 的自旋交换的产物)和两个极化的单自由基 (r14N-O-15N)# 和 (14N-O-15Nr)#(与r#)