摘要
胺的有氧氧化是有机合成中应用广泛的过程之一,其产物腈类化合物在医药、农药和香料等重要中间体被广泛应用。通过密度泛函理论(DFT)在分子水平上对Cu^(I)/amine仿生催化体系选择性氧化胺生成腈的详细反应机理、抗衡离子及溶剂对反应活性的控制因素进行了详细分析,发现机理分为两步进行:第一步为生成关键活性亚胺中间体(5)过程,该过程存在单核(PathⅠ)和双核(PathⅡ)反应路径,计算结果表明两条路径均为可能路径,并以单核机理(PathⅠ)路径为主导路径;第二步为生成腈过程,该过程存在两条可能路径(Path A和Path B),能量跨度模型分析表明Path B为优势路径,δE=16.6 kcal/mol,TOF=4.14 s^(-1)。此外,还发现抗衡离子I^(–)的存在明显降低了反应路径的能垒,而溶剂则对反应能垒没有明显影响。
The aerobic oxidation of amines is a widely used process in organic synthesis,and the resulting nitrile compounds are widely used as important intermediates in pharmaceuticals,pesticides,and fragrances.This paper,using Density Functional Theory(DFT),analyzed the detailed reaction mechanism of selective oxidation of amines to nitriles by a Cu^(I)/amine biomimetic catalytic system at the molecular level,as well as the controlling factors of reaction activity by counter ions and solvents.It was found that the mechanism includes two steps:Step 1 involves the generation of a key active imine intermediate(5),which has two reaction pathways,namely the single-core reaction pathway(Path I)and the dual-core reaction pathway(Path II).The calculation results show that both pathways are possible,and the single-core mechanism of(PathⅠ)is the dominant pathway.Step 2 is the nitrile generation process with two possible pathways(Path A and Path B).The energy span model analysis shows that Path B is the dominant pathway,δE of 16.6 kcal/mol,and TOF of 4.14 s^(-1).In addition,the presence of counter ion I^(—)significantly reduces the energy barrier of the reaction pathway,while the solvent has no significant effect on the reaction barrier.
作者
张子春
程琳
马丽莎
ZHANG Zichun;CHENG Lin;MA Lisha(School of Chemical Engineering,Inner Mongolia University of Technology,Hohhot 010051,China;School of Resources and Environmental Engineering,Inner Mongolia University of Technology,Hohhot 010051,China)
出处
《内蒙古工业大学学报（自然科学版）》
2024年第4期309-315,共7页
Journal of Inner Mongolia University of Technology：Natural Science Edition
基金
国家自然科学基金项目(21963009)
内蒙古自治区自然科学基金项目(2021MS02019)
内蒙古自治区教育厅支持地方高校改革发展资金项目(学科建设)。
关键词
胺
亚胺
密度泛函理论
amine
nitrile
density functional theory
