Nayak Mithilesh Kumar, Stubbe Jessica, Neuman Nicolás I, Narayanan Ramakirushnan Suriya, Maji Sandipan, Schulzke Carola, Chandrasekhar Vadapalli, Sarkar Biprajit, Jana Anukul
Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad, 500107, India.
Institut für Chemie und Biochemie, Anorganische Chemie, Freie Universität Berlin, Fabeckstraße 34-36, 14195, Berlin, Germany.
Chemistry. 2020 Apr 1;26(19):4425-4431. doi: 10.1002/chem.202000255. Epub 2020 Mar 9.
This work presents a stepwise reversible two-electron transfer induced hydrogen shift leading to the conversion of a bis-pyrrolinium cation to an E-diaminoalkene and vice versa. Remarkably, the forward and the reverse reaction, which are both reversible, follow two completely different reaction pathways. Establishing such unprecedented property in this type of processes was possible by developing a novel synthetic route towards the starting dication. All intermediates involved in both the forward and the backward reactions were comprehensively characterized by a combination of spectroscopic, crystallographic, electrochemical, spectroelectrochemical, and theoretical methods. The presented synthetic route opens up new possibilities for the generation of multi-pyrrolinium cation scaffold-based organic redox systems, which constitute decidedly sought-after molecules in contemporary chemistry.
这项工作展示了一个逐步可逆的双电子转移诱导氢迁移过程，该过程导致双吡咯啉鎓阳离子转化为E-二氨基烯烃，反之亦然。值得注意的是，正向和逆向反应都是可逆的，但遵循两条完全不同的反应途径。通过开发一种通往起始双阳离子的新型合成路线，在这类过程中建立这种前所未有的性质成为可能。通过光谱、晶体学、电化学、光谱电化学和理论方法相结合，对正向和逆向反应中涉及的所有中间体进行了全面表征。所展示的合成路线为基于多吡咯啉鎓阳离子支架的有机氧化还原体系的生成开辟了新的可能性，这类体系无疑是当代化学中备受追捧的分子。
