A diacetylene, 6-(2-pyridyl)-3,5-hexadiyn-l1-ol(PyHxD, 4) is synthesized and crystallized to obtain a monomer single crystal in order to investigate the effect of pyridyl substituent on topochemical polymerization. PyHxD was polymerized in the presence of water at room temperature although it is impossible to polymerize in bulk state because of its packing pattern. X-ray, UVVIS, Raman, IR spectroscopic studies were utilized to determine the structure of the monomer single crystals and the resulting polymers. (Z)-1-Methoxy-4-phenylbut-1-en-3-yne (MPBEY, 5) was polymerized over $NbCl_5$-based catalysts followed by pyrolysis to obtain new polyacene-based polymers. Poly[(Z)-1-methoxy-4-phenylbut-1-en-3-yne] (poly(MPBEY), 9) has the structure of fully conjugated backbone and completely aromatized on pyrolysis. The brown metathesis polymer was converted into black polyacene-based polymer on pyrolysis. The metathesis polymerization was influenced by substituents directly attached to the acetylene moiety. The polymers were characterized by GPC, FTIR, TGA, NMR, and X-ray diffraction studies.