催化量的非金属单电子氧化试剂引发的链式反应研究

This project proposes that the substrate is initiated by one electron oxidant to generate radical cation intermediate, and then through the separating and reuniting of cation and radical of the intermediate, new chain reaction will be induced. We will develop the radical cation mediated reaction methodology using epoxides as substrates, find new transformations and study on their mechanisms. We will focus on the development of useful new reactions that only need catalytic amounts of nonmetallic initiator under mild conditions with good generality and scope, and their application in the synthesis of complex molecules will be explored too. At the same time, we will also synthesize more nonmetallic one electron oxidants and prepare chiral one electron oxidants and try to apply them in asymmetrical synthesis. The study will explore the application of radical cation mediated chain reaction in organic synthesis, and help to understand the nature of the one electron oxidation.

本次申请拟通过合理的底物设计，经过单电子氧化引发产生底物自由基正离子，利用反应进程中活泼中间体上的正离子与自由基的轨道分离与重新合并，诱导原本不能发生的新型链式反应。总的目标是发展和完善经历自由基正离子过程的链式反应策略，在中性条件下，以探索环氧化合物单电子氧化后的新反应为切入点，进行具有合成价值的反应方法学研究，并探索其反应机理。重点是发展引发剂用量小、条件温和、操作简便、具有较好或独特选择性、具有较广阔底物适应性、具有较好实用价值的新反应，并探索其在复杂分子合成中的应用。同时也将着力于扩大稳定的非金属单电子引发试剂类型，并尝试将其拓展到不对称催化领域。近年来，单电子氧化反应研究渐入佳境，此研究的进行可以拓宽经历自由基正离子过程的反应在有机合成中的应用范围，有助于进一步认识和理解单电子氧化反应的本质和规律，将相关领域的研究引向深入。

通过单电子氧化方式活化底物分子，进而构建碳碳键以及碳杂原子键。相关工作进展主要分为两类：一、经历单电子氧化过程的氧化偶联反应；二、经历自由基正离子过程的链式反应。