Photochemical and Photocatalytic Amination Reactions with Monovalent Nitrogen-based Reactive Intermediates

胺化反应是有机合成中最重要的反应之一，在药物发现和材料科学中有着广泛的应用。通常，胺化反应是通过经典的取代反应或通过金属催化的偶联反应实现的。另一种选择是使用硝基中间体的胺化反应。然而，即使在今天，这种胺化反应仍然受到严格的限制，通常需要强制反应条件，因为碱性胺很容易抑制Lewis酸性过渡金属催化剂。然而，在光化学或光催化条件下，可以产生自由的硝基或自由的硝基阴离子，从而克服了传统的硝基转移反应的局限性。到目前为止，这种光化学或光催化的氮转移反应还只是零星地用于有机合成，目前的工作主要局限于高能紫外光的使用。可见光的使用只在几个选定的案例中进行了描述。在我们关于光化学和光催化氮转移反应的工作的基础上，我们现在想在这里详细研究这些反应。对反应性的了解和合适的新试剂的鉴定在实现这种硝基转移反应中起着核心作用，因此在开发可持续的合成方法和理解有机合成中的这一概念方法方面是一项重要的任务。在第一部分，计划的工作重点是多不饱和烃的光化学和光催化胺化反应，以及与碘烷的C-H胺化反应，以了解游离硝烯的反应性。进一步的工作重点是扩大胺化试剂的应用范围。将对不同的胺化试剂进行系统的研究，并在胺化反应中应用。所有计划中的研究包括详细的机理实验，如吸收光谱、荧光猝灭或循环伏安法，以及支持实验数据和阐明反应机理的密度泛函计算。

The amination represents one of the most important reactions in organic synthesis and is widely used in drug discovery or material sciences. Typically, aminations are realized via classic substitution reactions or via metal-catalyzed coupling reactions. An alternative lies within amination reactions using nitrene intermediates. However, such amination reactions are even today severely limited and often require forcing reaction conditions, since basic amines can easily inhibit the Lewis acidic transition metal catalysts. Under photochemical or photocatalytic conditions however, a free nitrene or a free nitrene radical anion can be generated, thereby overcoming classic limitations of nitrene transfer reactions. So far such photochemical or photocatalytic nitrene transfer reactions have only been used sporadically in organic synthesis, and current work is mainly limited to the use of high-energy UV light. The use of visible light has only been described in a few selected cases. Building on our work on photochemical and photocatalytic nitrene transfer reactions, we now want to examine these in detail here. The understanding of reactivity and identification of suitable new reagents plays a central role in enabling such nitrene transfer reactions and is therefore an important task in the development of sustainable synthetic methods and in understanding this conceptual approach in organic synthesis. In a first part, the planned work focuses on photochemical and photocatalytic amination reactions of poly-unsaturated hydrocarbons as well as C-H amination reactions with iodinanes to gain an understanding of the reactivity of free nitrenes. Further work focuses on expanding the range of applications with regard to the aminating reagent. Different amination reagents will be systematically investigated and applied in amination reactions. All planned studies include detailed mechanistic experiments, such as absorption spectroscopy, fluorescence quenching, or cyclic voltammetry, as well as DFT calculations to support the experimental data and elucidate reaction mechanisms.