Three zinc(Ⅱ), cobalt(Ⅱ), and nickel(Ⅱ) coordination polymers, namely [Zn(μ₃-cpna)(μ-dpea)_0.5]_n (1), [Co(μ₃-cpna)(μ-dpey)_0.5]_n (2), and [Ni(μ₃-cpna)(μ-dpey)_0.5(H₂O)]_n (3), have been constructed hydrothermally using H₂cpna (5-(4-carboxyphenoxy)nicotinic acid), dpea (1, 2-di(4-pyridyl)ethane), dpey (1, 2-di(4-pyridyl)ethylene), and zinc, cobalt, and nickel chlorides at 160 ℃. The products were isolated as stable crystalline solids and were characterized by IR spectra, elemental analyses, thermogravimetric analyses, and single-crystal X-ray diffraction analyses. Single-crystal X-ray diffraction analyses revealed that three compounds crystallize in the triclinic system, space group P1. Compounds 1-3 show 2D layer structures. The catalytic activities in the Knoevenagel condensation reaction of these compounds were investigated. Compounds 1 and 2 exhibit effective catalytic activities in the Knoevenagel condensation reaction at room temperature. For this reaction, various parameters were optimized, followed by the investigation of the substrate scope.