Abstract 4-(2-Ethynylphenyl) pyridine (10), 3-(2-ethynylphenyl) pyridine (11), 2-(2- trimethylsilylethynylphenyl) pyridine (26), and 3-ethynyl-2-phenylpyridine (13) were prepared from readily available pyridine precursors by standard coupling reactions. Pyrolysis of 10 at 810 C/0.5 Torr provided benzo [f] isoquinoline (45) and the benzopentalene dimer 47. Pyrolysis of 11 (820 C/0.5 Torr) afforded benzo [f] quinoline (50 ...