ARC Centre of Excellence for Free Radical Chemistry and Biotechnology, Australia.
Org Biomol Chem. 2015 Feb 28;13(8):2310-6. doi: 10.1039/c4ob02434f.
Competition kinetic studies augmented with laser-flash photolysis and high-level computational techniques [G3(MP2)-RAD], with [COSMO-RS, SMD] and without solvent correction, provide kinetic parameters for the ring closures of a series of 4-(alkylseleno)butyl radicals 1. At 22 °C rate constants (kc) that lie between 10(4)-10(7) s(-1) were determined experimentally and correlate with expectations based on leaving group ability. Activation energies (Eact) were determined to lie between 10.6 (R = Ph2CH) and 28.0 (R = n-Bu) kJ mol(-1), while log(A/s(-1)) values were generally between 9 and 10 in benzene. Computationally determined rate constants were in good-to-excellent agreement with those determined experimentally, with the COSMO-RS solvation model providing values that more closely resemble those from experiment than SMD.
竞争动力学研究，辅以激光闪光光解和高级计算技术[G3(MP2)-RAD]，以及[COSMO-RS、SMD]，不进行溶剂校正，为一系列 4-(烷基硒基)丁基自由基 1 的环闭反应提供了动力学参数。在 22°C 下，实验确定的速率常数（kc）在 10(4)-10(7) s(-1)之间，与基于离去基团能力的预期相符。活化能（Eact）测定值在 10.6（R = Ph2CH）和 28.0（R = n-Bu）kJ mol(-1)之间，而在苯中，log(A/s(-1))值通常在 9 和 10 之间。计算得到的速率常数与实验确定的速率常数非常吻合，与 SMD 相比，COSMO-RS 溶剂化模型提供的值更接近实验值。
