ABSTRACT
We present theoretical investigations on the nature and persistence of the strong central hydrogen bond of a tetraamido/diamino quaternized macrocycle. Our theoretical study of the NMR properties of the central hydrogen bond proved difficult to reconcile with the available experimental results, suggesting the possibility of the non-persistence of the central hydrogen bond of the macrocycle in solution. We demonstrate alternative scenarios, in which a tautomerization of the macrocycle in solution gives rise to the experimentally observed NMR shifts.
GRAPHICAL ABSTRACT
![](/cms/asset/ee585e37-5440-45cc-bff6-c056be57e40f/tmph_a_1539256_uf0001_oc.jpg)
KEYWORDS:
Acknowledgements
We dedicate this work to the memory of Professor Dieter Cremer.
Disclosure statement
No potential conflict of interest was reported by the authors.