Ultraviolet-emitting, alkoxy-functionalized poly(m-phenylene)

UV-emitting, highly soluble poly(3,5-(dodecyloxy)phenylene) (2) has been prepared by the nickel-catalyzed polymerization of 3,5-dichloro(dodecyloxy)benzene (1) in the presence of excess zinc, triphenylphosphine, and 2,2'-bipyridine. Structural characterization by H-1 and C-13 NMR spectroscopy agrees with the proposed polymer architecture of 2 consisting exclusively of meta-linkages. MALDI-MS in a dithranol matrix confirms the presence of the 260 g/mol repeat units contained in the polymer backbone. Elemental analysis is consistent with an average polymer chain consisting of approximately 40 monomer repeats capped by one terminal chlorine atom. GPC of 2 indicates an M(n) of 9700 g/mol (relative to polystyrene), well in aggreement with the M(n) of 8800 g/mol obtained by toluene VPO studies of the same sample. Thermal analysis has shown the polymer to possess high thermal stability with no weight loss in N-2 up to 350 degrees C. Solution fluorescence studies of the polymer in THF have determined the polymer to be primarily a UV emitter with only a slight tail extending into the visible region.