镍原子与环烷烃反应中C-C与C-H活化竞争机制研究

工程技术
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本文报道了2014年的一项理论研究，详细探讨了中性镍原子与环烷烃CnH2n（n=3到7）反应中的C-C和C-H键活化过程的竞争机制。这项工作主要针对Ni与C3H6和C4H8的反应，发现反应的主要途径涉及C-C键活化，而次要途径则侧重于C-H键的活化。实验结果与理论预测相吻合，表明镍原子在这些环烷烃分子中倾向于优先攻击C-H键，尤其是在C5H10至C7H14的分子中。 研究过程中，作者对感兴趣的反应路径上的中间体和过渡态进行了细致的结构分析。令人感兴趣的是，无论是C-C还是C-H键的活化，都通过一个单一的过渡态进行一步完成，这表明这两个过程在反应机理上是协同的。整体来说，C-H和C-C键的活化过程都是放热的，并且具有较低的能量障碍，这进一步证实了镍作为催化剂的有效性，能显著提升环烷烃CnH2n（n=3到7）的活性。 关键词包括“镍原子”，“环烷烃”，“C-H键活化”，“C-C键活化”，“反应机制”以及“催化作用”。这项研究不仅提供了对环烷烃与过渡金属反应行为的新见解，还为理解此类反应的调控策略以及设计更高效的催化剂提供了理论依据。对于理解有机合成反应中的金属催化剂选择性及其反应路径选择至关重要，尤其是在石油化工和材料科学领域。

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