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在帕拉催化型烯的氧化碳化中,存在竞争机制
Jaya Mehara1, Mariarosa Anania1,2, Pavel Kočovský2,3
1Department of Spectroscopy and Catalysis, Institute for Molecules and Materials, Radboud University Nijmegen, Heyendaalseweg 135, Nijmegen 6525 AJ, The Netherlands.
在催化醇基碳化中选择氧化剂决定了反应途径. 铜(II) 乙酸盐有利于不和 Ester 的形成,而p-基将反应转移到和 Ester 产品.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 反应机制 反应机制
背景情况:
- 催化碳化是,乳和乳酸盐的关键合成方法.
- 基的基碳化可以通过不同的催化循环产生和或不和 Ester.
- 文献中缺乏对有利于特定氧碳化物产品的条件的一致理解.
研究的目的:
- 为了研究和比较 styrene methoxycarbonylation 的两个催化循环中的中间体的动力学.
- 阐明氧化剂在控制反应路径和产品选择性的作用.
- 了解氧化和化循环之间的机械切换.
主要方法:
- 在 styrene methoxycarbonylation 过程中使用质谱测量监测短寿命中间体.
- 在同一反应中,氧化和化循环中的中间体的动态分析.
- 系统地改变氧化剂 (p-金与铜酸) 来观察对反应条件和产品的影响.
主要成果:
- 氧的中间循环,产生不和,最初是更快的.
- 随着时间的推移,不断变化的条件有利于化循环,产生和 Ester.
- 铜酸维护pH值,促进氧化循环和不和 Ester 的形成.
- p-诺基降低了pH值,将反应转向了化循环和和的 Ester.
结论:
- 氧化剂,而不是催化剂,通过诱导机械开关来控制反应结果.
- 铜(II) 乙酸盐通过氧化途径选择性地促进不和的合成.
- 了解这些原理有助于发展和应用氧碳化反应.
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