دورية أكاديمية
Mechanistic studies of isomeric [2]rotaxanes consisting of two different tetrathiafulvalene units reveal that the movement of cyclobis(paraquat-p-phenylene) can be controlled
| العنوان: | Mechanistic studies of isomeric [2]rotaxanes consisting of two different tetrathiafulvalene units reveal that the movement of cyclobis(paraquat-p-phenylene) can be controlled |
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| المؤلفون: | Jensen, Sofie K., Neumann, Mathias S., Frederiksen, Rikke, Skavenborg, Mathias L, Larsen, Mads C., Wessel, Stinne E., Jeppesen, Jan O. |
| المصدر: | Jensen , S K , Neumann , M S , Frederiksen , R , Skavenborg , ML , Larsen , M C , Wessel , S E & Jeppesen , J O 2023 , ' Mechanistic studies of isomeric [2]rotaxanes consisting of two different tetrathiafulvalene units reveal that the movement of cyclobis(paraquat-p-phenylene) can be controlled ' , Chemical Science , vol. 14 , no. 43 , pp. 12366-12378 . https://doi.org/10.1039/d3sc04408dTest |
| سنة النشر: | 2023 |
| المجموعة: | University of Southern Denmark: Research Output / Syddansk Universitet |
| الوصف: | Controlling the movement in artificial molecular machines is a key challenge that needs to be solved before their full potential can be harnessed. In this study, two isomeric tri-stable [2]rotaxanes 1·4PF 6 and 2·4PF 6 incorporating both a tetrathiafulvalene (TTF) and a monopyrrolotetrathiafulvalene (MPTTF) unit in the dumbbell component have been synthesised to measure the energy barriers when the tetracationic cyclobis(paraquat-p-phenylene) (CBPQT 4+ ) ring moves across either a TTF 2+ or an MPTTF 2+ dication. By strategically exchanging one of the thiomethyl barriers on either the TTF unit or the MPTTF unit with the bulkier thioethyl group, the movement of the CBPQT 4+ ring in 1 4+ and 2 4+ can be controlled to take place in only one direction upon tetra-oxidation. Cyclic voltammetry and 1 H NMR spectroscopy were used to investigate the switching mechanism and it was found that upon tetra-oxidation of 1 4+ and 2 4+ , the CBPQT 4+ ring moves first to a position where it is located between the TTF 2+ and MPTTF 2+ dications producing high-energy co-conformations which slowly interconvert into thermodynamically more stable co-conformations. The kinetics of the movement occurring in the tetra-oxidised [2]rotaxanes 1 8+ and 2 8+ were studied at different temperatures allowing the free energy of the transition state, when CBPQT 4+ moves across TTF 2+ (21.5 kcal mol −1 ) and MPTTF 2+ (20.3 kcal mol −1 ) at 298 K, to be determined. These results demonstrate for the first time that the combination of a TTF and an MPTTF unit can be used to induce directional movement of the CBPQT 4+ ring in molecular machines with a 90% efficiency. |
| نوع الوثيقة: | article in journal/newspaper |
| وصف الملف: | application/pdf |
| اللغة: | English |
| العلاقة: | https://portal.findresearcher.sdu.dk/da/publications/485f3751-bf89-4bdf-b0bf-ef999f2640aaTest |
| DOI: | 10.1039/d3sc04408d |
| الإتاحة: | https://doi.org/10.1039/d3sc04408dTest https://portal.findresearcher.sdu.dk/da/publications/485f3751-bf89-4bdf-b0bf-ef999f2640aaTest https://findresearcher.sdu.dk/ws/files/244528691/d3sc04408d.pdfTest |
| حقوق: | info:eu-repo/semantics/openAccess |
| رقم الانضمام: | edsbas.738A3E4E |
| قاعدة البيانات: | BASE |
| DOI: | 10.1039/d3sc04408d |
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