<p class="MDPI12title">Cyclocondensation Reaction of <em>C</em>-Tetra(Ethyl)Pyrogallol[4]Arene: Its Study and the Evaluation of Its Thermodynamic Properties

Pyrogallol[4]arenes are polyhydroxylated compounds obtained by condensation between pyrogallol and different aldehydes. Depending on both the type of aldehyde (aromatic or aliphatic) and the reaction time, these compounds can be obtained in different conformations, the most common being the crown and chair conformations. Using the conventional synthesis method, it is possible to obtain, in addition to the chair or crown conformers, other molecular associations, such as dimer capsules. The research in this study focuses on the synthesis products obtained from the condensation between pyrogallol and propanal. These products obtained were characterized using spectroscopic methods, finding that it is possible to obtain, in addition to the crown conformation, the dimer capsule of the macrocycle. Finally, the volumetric properties of these conformers were evaluated in dimethylsulfoxide (DMSO) solution and at several temperatures.