Modification of DOBOB mesogen

As part of our attempt to prepare a molecular spinning machine, we synthesized a new discotic liquid crystal polymethacrylate based on taper-shaped monoesters of triethylene glycol with 3,4,5-tris(p-dodecyloxybenzyloxy-m-methoxybenzyloxy)benzoic acid (DOVOB acid). In advance of this effort, we embarked on the modification of the DOBOB mesogen to provide segmental units with the requisite mobility to produce a nanorotor. The induction of a glass transition for the taper-shaped columnar discotic mesogen 3,4,5-tris(p-dodecyloxybenzyloxy)benzoic (DOBOB) acid was achieved by attaching a methoxy group to the benzyl unit resulting in 3,4,5-tris(p-dodecyloxy-m-methoxybenzyloxy) benzoic (DOVOB) acid, using the Adam–Gibbs configurational entropy theory as the guideline. Solid state deuterium NMR techniques have been used to study the rotation dynamics of both mesogens.