Characterization of nanoporous cavity of quardruply bridged calix[6]arenes by means of hyperpolarized 129Xe NMR.

: The bridged calix[6]arenes, which are well known as cavitands to capture ions and molecules, were characterized via the hyperpolarized 129Xe NMR. Also, we could deduce the pathway of a guest molecule into hosts and estimate the pore diameter of bridged calix[6]arenes. The characterized results of nanoporous cavity by the hyperpolarized 129Xe NMR corresponded with the measurement from the X-ray structure. This study showed that the hyperpolarized 129Xe NMR could be used as a promising tool to characterize nanoporous cavity of host compounds with low surface area.