The Role of Weak Interactions in Supramolecular Compounds: A Synthetic and Theoretical Study of Novel Elongated Cavitands

A new resorcinol-based tetraazidocavitand (2) has been prepared via substitution reaction started from the corresponding tetrabromocavitand (1). This tetraazidocavitand was used as a starting material for azide-alkyne cycloaddition with different alkynes and this way four novel deepened cavitands have been synthesized under mild conditions. Molecular dynamics, semiempirical PM6 and DFT PBEPBE/6-31G(d,p) studies have been carried out for these new triazole ring containing structures to reveal the exact geometry in solution, furthermore theoretical NMR chemical shift calculations were completed at B3LYP - D3/6-31G(d,p) GIAO level in order to compare with the experimental NMR data. QTAIM analysis at B3LYP - D3/def2-TZVP level was performed and NCI isosurfaces were generated to reveal the potential intramolecular weak interactions between the cavitand branches.