Three copper(Ⅱ), nickel and cadmium(Ⅱ) complexes, namely [Cu₂(μ-H₂dbda)₂(phen)₂]·2H₂O (1), [Ni(μ-H₂dbda)(μ-bpb)(H₂O)₂]_n (2), and [Cd(μ-H₂dbda)(μ-bpa)]_n (3), have been constructed hydrothermally using H₄dbda (4,4′-dihydroxy-[1,1′-biphenyl]-3,3′-dicarboxylic acid), phen (1,10-phenanthroline), bpb (1,4-bis(pyrid-4-yl)benzene), bpa (bis(4-pyridyl)amine), and copper, nickel and cadmium 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 complexes crystallize in the monoclinic P2₁/n, tetragonal I42d, and orthorhombic P2₁2₁2 space groups. The complexes exhibit molecular dimers (1) or 2D metal-organic networks (2 and 3). The catalytic performances in the Knoevenagel reaction of these complexes were investigated. Complex 1 exhibits an effective catalytic activity and excellent reusability as a heterogeneous catalyst in the Knoevenagel reaction at room temperature.