Direct 129Xe-NMR spectroscopy evidence of a mesogenic dendrimer with free void space

A dendrimer with three-fold symmetry and piperazinoamido moieties was prepared in ∼35% yield. This molecule was observed to exhibit columnar phases on thermal treatment and have free void space in the mesogenic and solid states based on a 129Xe-NMR study. The piperazinoamido moiety was indicated in a theoretical calculation to cause the dendritic framework to become twisted between the central core and periphery—thus resulting in the dendrimer forming a free void space inside the framework after having self-assembled into columnar stacks.