由Rh(III) 复合体催化的素衍生烯乙烯的氧中性脱聚合:一个机械的洞察力
Yan Zhang1,2, Yafei Luo1,2, Changwei Hu1
1Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, Sichuan, 610064, P. R. China. suzhishan@scu.edu.cn.
Physical chemistry chemical physics : PCCP
|September 4, 2024
概括
催化剂通过分裂乙烯键来促进素脱聚合. 虽然素可以充当源,但其有限的供应会影响这种氧化还原中性过程中的产品产量.
科学领域:
- 计算化学计算化学
- 催化剂是一种催化剂.
- 生物质转换生物质转换
背景情况:
- 素脱聚合对于将生物质转化为有价值的化学物质至关重要.
- 乙烯键是素复杂结构中的关键环节.
- 复合体在催化红素分解方面表现有前途.
研究的目的:
- 阐明由素衍生的乙烯二聚合物的氧化还原中性脱聚合的机制.
- 为了研究-二 ([Rh]) 和双核 ([2Rh]) 复合物的催化活性.
- 了解源在催化过程中的作用.
主要方法:
- 使用密度函数理论 (DFT) 的计算.
- 使用了TPSSh-D3 ((BJ) / def2-TZVP (SMD,水) 理论水平.
- 分析的重点是 β-O-4 模型化合物的 Cβ-O 键裂变.
主要成果:
- 该机制涉及脱到子中间体,其次是还原性以太键裂解.
- 氧化 ([Rh]-OH) 和化 ([Rh]-H) 的中间体起着关键的作用.
- 双核复合体 ([2Rh]-H) 显示出高反应性与低能障碍的Cβ-O键断裂 (35.3 kcal mol-1).
- 素本身可以作为产生活性化物种的源.
结论:
- 催化系统有效地在素模型化合物中切割乙烯键.
- 芳香产品形成的效率受到素供应的限制.
- 需要进一步优化,以提高实际应用中的产量.
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