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协调诱导的旋转状态转换切换了 (II) 氨酸在进化反应中的反应性
Hao-Zong Xue1, Jia-Hui Wu1, Bing-Wu Wang1
1Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China.
Angewandte Chemie (International ed. in English)
|November 19, 2024
概括
旋转状态显著影响色氨酸催化剂对的进化. 低旋转有利于化,而高旋转则通过不同的途径促进的进化.
科学领域:
- 无机化学 无机化学 有机化学
- 催化剂是一种催化剂.
- 电化学 电化学 电化学
背景情况:
- 电子旋转在与金属复合物的反应中至关重要,但对其精确作用的实验数据有限.
- (II) 氨酸是重要的催化剂,具有可调的自旋状态,具有反应控制的潜力.
研究的目的:
- 为了研究 (II) 5,10,15,20-tetrakis ((pentafluorophenyl) 氨酸在电催化进化中的自旋依赖性选择性.
- 阐明进化的机制和酸化作为催化剂旋转状态的函数.
主要方法:
- 使用 (II) 氨酸催化剂的电催化演化反应 (HER).
- 通过轴性皮里丁协调改变催化剂自旋状态.
- 使用cobaltocene (CoCp2) 和p-toluenesulfonate. pyridinium的化学还原研究.
- 密度函数理论 (DFT) 计算以建模反应路径.
主要成果:
- 皮里丁协调诱导了Ni (II) 中心的低旋转到高旋转状态开关.
- 在pyridine (低自旋状态) 的存在下,通过电子转移和随后的质子转移发生甲的β化.
- 没有化物 (高旋转状态),的进化主要是通过协同的质子合电子转移发生的.
- 在化学还原实验中观察到类似的自旋依赖选择性.
结论:
- 催化剂中中心的自旋状态决定了反应路径和选择性.
- 高旋转状态有利于电催化的进化,而低旋转状态促进化.
- DFT计算证实,高旋转状态丰富了连接体电子密度,将质子转向β外围.
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