0000000001301460
AUTHOR
Henrik Hupatz
An aryl-fused redox-active tetrathiafulvalene with enhanced mixed-valence and radical-cation dimer stabilities.
Molecular recognition of stable organic radicals is a relatively novel, but important structural binding motif in supramolecular chemistry. Here, we report on a redox-switchable veratrole-fused tetrathiafulvalene derivative VTTF which is ideally suited for this purpose and for the incorporation into stimuli-responsive systems. As revealed by electrochemistry, UV/Vis measurements, X-ray analysis, and electrocrystallisation, VTTF can be reversibly oxidised to the corresponding radical-cation or dication which shows optoelectronic and structural propterties similar to tetrathiafulvalene and tetrakis(methylthio)tetrathiafulvalene. However, theoretical calculations, variable temperature EPR, and…
Dual-stimuli pseudorotaxane switches under kinetic control
A series of dumbbell-shaped sec-ammonium salts with bulky (pseudo)stoppers (‘speed bumps’) were tested for their ability to form pseudorotaxanes with a redox-switchable, tetrathiafulvalene (TTF)-decorated [24]crown-8 ether. Depending on the size of the pseudostoppers, fast (less than ten minutes), slow (hours to days) and very slow (no pseudorotaxanes observed) threading has been observed. NMR spectroscopy as well as tandem mass spectrometry indicate the formation of non-threaded face-to-face complexes prior to pseudorotaxanes formation. Both isomers can be distinguished by their substantially different stability in collision-induced dissociation (CID) experiments. Two external stimuli affe…
Thermodynamic and electrochemical study of tailor-made crown ethers for redox-switchable (pseudo)rotaxanes
Crown ethers are common building blocks in supramolecular chemistry and are frequently applied as cation sensors or as subunits in synthetic molecular machines. Developing switchable and specifically designed crown ethers enables the implementation of function into molecular assemblies. Seven tailor-made redox-active crown ethers incorporating tetrathiafulvalene (TTF) or naphthalene diimide (NDI) as redox-switchable building blocks are described with regard to their potential to form redox-switchable rotaxanes. A combination of isothermal titration calorimetry and voltammetric techniques reveals correlations between the binding energies and redox-switching properties of the corresponding ps…
Chiroptical inversion of a planar chiral redox-switchable rotaxane.
Reversible redox-switching of a planar chiral [2]rotaxane with a tetrathiafulvalene-bearing crown ether macrocycle generates a complete sign reversal of the main band in the ECD spectrum, as shown by experiment and rationalised by DFT calculations.
CCDC 1910670: Experimental Crystal Structure Determination
Related Article: Marius Gaedke, Felix Witte, Jana Anhäuser, Henrik Hupatz, Hendrik V. Schröder, Arto Valkonen, Kari Rissanen, Arne Lützen, Beate Paulus, Christoph A. Schalley |2019|Chemical Science|10|10003|doi:10.1039/C9SC03694F
CCDC 1581480: Experimental Crystal Structure Determination
Related Article: Hendrik V. Schröder, Felix Witte, Marius Gaedke, Sebastian Sobottka, Lisa Suntrup, Henrik Hupatz, Arto Valkonen, Beate Paulus, Kari Rissanen, Biprajit Sarkar, Christoph A. Schalley|2018|Org.Biomol.Chem.|16|2741|doi:10.1039/C8OB00415C
CCDC 2073308: Experimental Crystal Structure Determination
Related Article: Marius Gaedke, Henrik Hupatz, Hendrik V. Schröder, Simon Suhr, Kurt F. Hoffmann, Arto Valkonen, Biprajit Sarkar, Sebastian Riedel, Kari Rissanen, Christoph A. Schalley|2021|Org.Chem.Front.|8|3659|doi:10.1039/D1QO00503K
CCDC 1586984: Experimental Crystal Structure Determination
Related Article: Hendrik V. Schröder, Felix Witte, Marius Gaedke, Sebastian Sobottka, Lisa Suntrup, Henrik Hupatz, Arto Valkonen, Beate Paulus, Kari Rissanen, Biprajit Sarkar, Christoph A. Schalley|2018|Org.Biomol.Chem.|16|2741|doi:10.1039/C8OB00415C