在中多电子转移:酸连接物的影响
Kate M Waldie1, Srinivasan Ramakrishnan1, Sung-Kwan Kim1
1Department of Chemistry, Stanford University , Stanford, California 94305, United States.
Journal of the American Chemical Society
|March 7, 2017
概括
一个新型的复合物与酸在轻微的电位下经历了罕见的两电子的减少. 这一发现促进了单核过渡金属复合物的发展,以实现高效的双电子转换.
科学领域:
- 有机金属化学
- 电化学
- 无机化学
背景情况:
- 单核第一排过渡金属复合物在催化过程中至关重要.
- 在温和的电位下实现多电子还氧化过程仍然是一个重大挑战.
- 酸连接体为氧化还原调节提供独特的电子特性.
研究的目的:
- 为了研究二聚-酸复合物的电化学行为.
- 探索在轻微电位下实现两电子减小的可能性.
- 阐明控制观察到的氧化还原行为的结构和电子因素.
主要方法:
- 使用循环电压测量来研究该复合物的电化学特性.
- 使用cobaltocene进行化学降解以隔离减少的物种.
- 使用X射线结晶学,光谱学和密度函数理论 (DFT) 的计算进行了表征.
主要成果:
- 滴定复合物[CpCo(azpy) ((CH3CN))) ((ClO4) 2 (1) 在 -0.16 V 与 Fc0/+ 的情况下表现出可逆的两电子减小.
- 这与类似的双和酸复合物形成鲜明对比,这些复合物呈现出连续的单电子减小.
- 隔离的双减复合物[CpCo(azpy) (2) 是稳定在空气中且具有二磁性.
- DFT计算与结构重组和金属-合体轨道重叠与两个电子的减少相关.
结论:
- 酸连接体在复合体中促进了独特的两电子还原路径.
- d轨道和π*轨道之间的有效重叠是观察到的潜在反转的关键.
- 这项工作代表了开发用于温和电位多电子氧化还原反应的单核复合物的重要一步.
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