5,5'-Substituted-2,2'-bipyridines: A new series of liquid crystalline materials

Dissymmetric functionalization of 5,5'-dimethyl-2,2'-bipyridine with a 'stilbene type' chromophore bearing a terminal alkoxy group leads to a new family of mesomorphic compounds exhibiting a rich thermotropic polymorphism. A succession of smectic B, smectic A and nematic phases was observed. For the octyloxy compound, an additional phase was detected which was hexatic in symmetry.