Photoredox catalytic activation of sulfur hexafluoride for the synthesis of pentafluorosulfanylated organic compounds

光氧化还原催化活化六氟化硫合成五氟磺酰化有机化合物

• 批准号: 505932961
• 负责人: Professor Dr. Hans-Achim Wagenknecht
• 金额: --
• 依托单位: Laboratorium für Organische Chemie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/505932961?language=en
• 关键词: Photoredox; catalytic; activation; sulfur; hexafluoride

The incorporation of fluorinated substituents into organic molecules significantly affects their physical, chemical, biological and pharmaceutical properties. Accordingly, fluorinated compounds play an important role in pharmaceutical chemistry, in agrochemistry, in dye chemistry, and in material chemistry for optoelectronics. Among the fluorinated substituents, the pentafluorosulfanyl group is probably the most unexplored one, therefore often designated as “forgotten functional group”. Pentafluorosulfanylated compounds are prospective alternatives to other fluorinated compounds, thus the pentafluorosulfanyl group does not simply represent a more expensive perfluorinated group. So far, the exploration and the use of the pentafluorosulfanyl group in organic compounds are drastically limited by the difficult synthetic accessibility due to the toxicity of the available pentafluorosulfanylation reagents. Sulfur hexafluoride is an important alternative, but chemically completely inert. Thermal methods efficiently destruct sulfur hexafluoride, but cannot easily be applied for pentafluorosulfanylations. The overall goal of this project is to use sulfur hexafluoride as pentafluorosulfanylation reagent by means of advanced photoredox catalysis to synthesize valuable pentafluorosulfanylated organic compounds and building blocks. In the first two stages we plan to advancing N-phenylphenothiazines as well as N,N-diphenylphenazines as tunable organophotoredox catalysts, and the photoredox catalytic pentafluorosulfanylation of styrene derivatives with heterocyclic components. For the broader use of the pentafluorosulfanyl substituent in medicinal and material chemistry, an efficient and non-toxic preparation of aromatic pentafluorosulfanylated compounds is crucial. Accordingly, we plan to prepare pentafluorosulfanylated arenes from organic boronic acid esters and trifluoroborates that are activated in a photoredox catalytic approach and subsequently cleaved into carbon-centered radicals. Furthermore, we plan to extend this chemistry to dehydroalanine derivatives to synthesize pentafluorosulfanylated amino acids and peptides. The incorporation of pentafluorosulfanylated amino acids is important for a novel class of amino acids with altered properties and/or as fluorine NMR labels. Taken together, this project will significantly broaden the substrate scope of photoredox catalytic pentafluorosulfanylation and bring it to a level that these compounds can be considered for the chemistry disciplines (mentioned in the second sentence) in the future.

有机分子中含氟取代基的引入对有机分子的物理、化学、生物和药学性质有重要影响。相应地，含氟化合物在药物化学、农业化学、染料化学和光电子材料化学中发挥着重要的作用。在含氟取代基中，五氟取代基可能是最未被开发的，因此常被称为“被遗忘的官能团”。五氟磺化化合物是其他含氟化合物的潜在替代品，因此五氟磺酰基团不仅仅代表更昂贵的全氟化基团。到目前为止，由于现有的五氟磺化试剂的毒性，五氟磺酰基团在有机化合物中的探索和使用受到了很大的限制，因为合成的难度很大。六氟化硫是一种重要的替代品，但在化学上完全是惰性的。热法可以有效地破坏六氟化硫，但不容易用于五氟磺化反应。本项目的总体目标是以六氟化硫作为五氟磺化试剂，通过先进的光催化氧化还原技术合成有价值的五氟磺化有机化合物和积木。在前两个阶段，我们计划发展N-苯基吩噻嗪和N，N-二苯基吩嗪作为可调有机光氧化还原催化剂，以及具有杂环成分的苯乙烯衍生物的光氧化还原催化五氟磺化反应。为了使五氟取代基在医药和原料化学中得到更广泛的应用，一种高效无毒的芳香族五氟磺基化合物的制备是至关重要的。因此，我们计划从有机硼酸酯和三氟硼酸盐中制备五氟磺化芳烃，这些化合物在光氧化还原催化方法中被活化，然后裂解成以碳为中心的自由基。此外，我们计划将这种化学扩展到脱氢丙氨酸衍生物，以合成五氟磺基氨基酸和多肽。五氟磺化氨基酸的引入对于一类具有改变性质和/或作为氟核磁共振标记的新型氨基酸是重要的。综上所述，该项目将大大拓宽光氧化还原催化五氟磺化反应的底物范围，并使其达到未来可以考虑将这些化合物用于化学学科(第二句中提到的)的水平。