Soluble precursor polymers 8 and 14 were successfully synthesized via the palladium-mediated condensation of 4,4’-(1,3,2-dioxaborolan-2-yl)biphenyl (7) with the bis(p-bromophenyl)norbornadiene monomer 5 and the bis(p-bromophenyl)norbornene monomer 13, respectively. The number-averaged molecular weights of these materials were determined by GPC-LS to be 34 000 for 8 and 75 000 for 14. Thermolysis of 8 by a retro-Diels-Alder reaction began at 260 degrees C and appeared (by GC-MS analysis of the volatile byproducts) to yield a conjugated polymer with both alkyne and cyclopentadiene functionalities in the polymer backbone; however, TGA analysis indicated that the transformation was accompanied by some decomposition. The analogous thermolysis of 14 to yield the polymer with a double bond in the backbone began at 230 degrees C and appeared to proceed without the concomitant decomposition.