在室温稳定的MnIII-Hydroperoxo复合物的光谱性质和反应性
Elizabeth N Grotemeyer1, Zahra Aghaei1, Timothy A Jackson1
1The University of Kansas, Department of Chemistry and Center for Environmentally Beneficial Catalysis, 1567 Irving Hill Road, 66045, Lawrence, KS, USA.
Chemistry (Weinheim an der Bergstrasse, Germany)
|September 11, 2024
概括
研究人员合成和表征了一种罕见的 (III) - 氧化复合物. 这种新的复合物在氧化反应中比其 (III) - 烯类同类物显著更具反应性.
科学领域:
- 协调化学 协调化学
- 氧化催化剂氧化催化剂
- 有机金属化学 有机金属化学
背景情况:
- 激活过氧化的催化剂对于有机转化如环氧化和C-H氧化至关重要.
- 机制经常提出Mn(III) -hydroperoxo中间体,但明确的例子很少.
- 属性经常从Mn(III) -alkylperoxo类似物中推断出来.
研究的目的:
- 为了合成和表征一个明确的Mn(III) - 水氧复合物.
- 为了研究这种新型物种的反应性和电子性质.
- 为了比较它的反应性与相关的Mn(III) -hydroxo和Mn(III) -alkylperoxo复合物.
主要方法:
- 一个Mn(III) - 氧复合物的反应与过氧化和酸.
- 使用电子吸收,1H NMR,IR和ESI-MS进行表征.
- 热衰变和与基质发生反应的动力学研究 (TEMPOH,PPh3).
- 密度函数理论 (DFT) 和时间依赖 (TD-DFT) 计算.
主要成果:
- 形成一个深绿色的Mn(III) -水氧复合体,[MnIII(OOH)(6Me-dpaq) ]+ (2).
- 综合体2展示了第一阶段的热衰变动力学.
- 复合物2的反应能力是Mn (III) - 氧前体与TEMPOH的两倍.
- 复合物2与PPh3的反应性比其Mn(III) - 基氧类似物高600倍.
结论:
- 一个明确的Mn (III) - 氧化合物复合物已成功合成和表征.
- 这种Mn(III) - 基氧物种与Mn(III) - 基氧类似物相比显示出显著增强的反应性.
- 这些发现为催化氧化反应的机制提供了宝贵的见解.
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