Studies towards Enantioselective Silver-Catalysed C-H Amination via Nitrene Transfer using Multi-Functional Ligands

第1年：CDT所有一年级学生成员的通用培训活动。第2-4年：通过硝基转移(NT)的C-H胺化能够将C-H键直接转化为C-N键，并具有改变含氮分子合成的潜力。在过去的25年里，NT反应作为交叉偶联反应的替代方法引起了人们的极大兴趣。虽然在C-H胺化反应中的化学选择性和位置选择性现在已经得到很好的证实，但对映体选择性仍然是一个挑战。通常的情况是，对于给定的底物类别，需要精心设计的手性配体才能看到任何对映体诱导。最近，银由于其广泛的配位几何构型和承载反应物与配体之间的非共价相互作用(NCIS)的能力而引起人们的兴趣。通过NT的对映选择性银催化的C-H胺化反应很少被探索，到目前为止只有少数成功的例子被开发出来。我们的研究组已经成功地证明了C-H硼化反应中的对映体选择性可以由与非手性阴离子配体Ir结合的手性阳离子来控制。由于这一方法有可能广泛应用于其他一系列过渡金属(TM)催化的反应，将使用银催化的C-H胺化反应来研究离子对配体体系。

Year 1: Generic training activities for all first-year student members of the CDT.Year 2-4: C-H amination via nitrene transfer (NT) is able to convert C-H bonds directly to C-N bonds and holds the potential to transform the synthesis of nitrogen-containing molecules. NT reactions have gained much interest in the last 25 years as an alternative to cross-coupling reactions. Whilst chemo- and site-selectivity in C-H amination reactions is now well established, enantioselectivity is still a challenge. It is often the case that elaborate chiral ligands are required to see any enantioinduction for a given substrate class. Recently, silver has gained interest for its wide range of coordination geometries and ability to host non-covalent interactions (NCIs) between reactants and ligands. Enantioselective silver-catalysed C-H amination via NT has been seldom explored with only a handful of examples successfully developed thus far. Our group has successfully shown that enantioselectivity in C-H borylation can be controlled by a chiral-cation that is associated with an achiral, anionic ligand for iridium. With the potential for this methodology to be broadly applied to a range of other transition metal (TM) catalysed reactions, the ion-paired ligand system will be investigated with a silver-catalysed C-H amination protocol.