engleski

Structural and thernodynamic features of diamondoid ammonium salt inclusion complexess with cyclodextrins

Functionalized diamondoid ammonium salts are an intriguing class of compounds capable of forming ultra-stable complexes with cucurbituril hosts (CB[n]) in aqueous environment with binding constants up to 1015 mol–1 dm3.1 Inspired by these properties, we decided to broaden the research scope of inclusion complexes stabilized by hydrophobic interactions between various cage ammonium salt guests and cyclodextrin (CD) as a different macrocycle host molecule.2 Herein we present the synthesis of a continued series of diamondoid ammonium salts and a detailed thermodynamic study of their complexation with β- and γ-CDs. The complex stability constants were determined by ITC and 1H NMR titrations in aqueous solutions. Additional NMR spectroscopic techniques (1H-1H NOESY, 1H DOSY) along with computational methods were employed to provide a deeper insight into the thermodynamics of hydrophobically driven complexations and structural features of the formed supramolecules. The binding strength was assessed as a function of diamondoid salt size, functional group position and cyclodextrin cavity size and by varying these parameters, a structure- selectivity relationship can be determined in order to facilitate the design of next generation of suitable guests.

Cyclodextrins ; Diamondoid Ammonium Salts ; Supramolecular Chemistry ; Inclusion complexes ; thermodynamic and NMR study

This work has been supported by the Croatian Academy of Science and Arts and the Croatian Science Foundation (UIP-2017-05-9653 (DiamMat), IP-2019-04- 9560 (MacroSol)).