在中心上用水氧化烯
Tapas Ghatak1, Mithun Sarkar1, Shrabani Dinda1
1Department of Chemistry and Center for Environmental Science and Engineering, Indian Institute of Technology Kanpur, Kanpur 208016, India.
Journal of the American Chemical Society
|May 8, 2015
概括
这项研究证明了使用水对1,5-环氧的催化氧化. 一个纳夫提里丁连接体促进了水的激活,产生了新的伊里达-乙烯和oxo-irida-allyl化合物.
科学领域:
- 有机金属化学 有机金属化学
- 催化剂是一种催化剂.
- 无机化学 无机化学 有机化学
背景情况:
- 金属催化氧化反应在合成化学中至关重要.
- 传统上,使用过氧化 (H2O2) 或分子氧 (O2) 等氧化剂.
- 在金属中心的水激活仍然是一个重大挑战.
研究的目的:
- 为了研究使用水作为氧气来源对1,5-环氧八二烯 (COD) 的直接氧化.
- 探索纳夫胺基连接体在促进水激活和随后的氧化中的作用.
- 描述这种新型反应途径的中间产品和最终产品.
主要方法:
- 合成和表征一个含有纳夫铁连接体的复合体.
- 复合物的反应与水存在的1,5-环氧 octadiene (COD).
- 使用光谱技术 (例如NMR,X射线晶体学) 隔离和阐明反应产品的结构.
- 使用密度函数理论 (DFT) 阐明反应机制的计算研究.
主要成果:
- 用水作为唯一的氧气来源,成功氧化COD形成化和化-化化合物.
- 确定了一种关键的结相互作用,其中涉及促进水核友性攻击的纳夫提里丁配体.
- 隔离稳定的伊里达-乙烯和-伊里达-基中间体,通常通过H2O2或O2.2获取.
- DFT的计算证实了配体辅助的水激活机制.
结论:
- 在金属催化氧化反应中,水可以作为有效的氧原子来源.
- 纳菲西里丁配体可以在激活水中发挥关键作用,用于对协调基质的核友性攻击.
- 这项工作为有价值的有机金属中间体提供了一个新的,可能更绿色的途径,绕过了传统氧化剂的需求.
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