J Am Chem Soc. 2018 May 2;140(17):5696-5700. doi: 10.1021/jacs.8b02508. Epub 2018 Apr 20.
One-electron reduction of CuEL (L = tris(β-diketiminate)cyclophane, and E = S, Se) affords [CuEL], which reacts with CO to yield exclusively CO (95% yield, TON = 24) and regenerate CuEL. Stopped-flow UV/visible data support an A→B mechanism under pseudo-first-order conditions ( k = 115(2) s), which is 10 larger than those for reported copper complexes. The k values are dependent on the countercation and solvent (e.g., k is greater for [K(18-crown-6)] vs (PhP)N, and there is a 20-fold decrease in k in THF vs DMF). Our results suggest a mechanism in which cations and solvent influence the stability of the transition state.
一电子还原 CuEL（L = 三（β-二酮亚胺）环戊二烯，E = S，Se）得到 [CuEL]，它与 CO 反应仅生成 CO（95%产率，TON = 24）并再生 CuEL。准一级条件下的停流 UV/可见数据支持 A→B 机理（k = 115(2) s），这比报道的铜配合物的 k 值大 10 倍。k 值取决于抗衡阳离子和溶剂（例如，[K(18-冠-6)] 的 k 值大于 (PhP)N，在 THF 中 k 值比在 DMF 中降低 20 倍）。我们的结果表明，阳离子和溶剂影响过渡态的稳定性的机制。
