Synthesis and Crystal Structure of a 2D Cu Framework Constructed from Dinuclear Building Units

摘要

A novel 2D Cu coordination polymer [Cu4(pca)4(H2O)2(DMSO)2·2DMSO·2H2O]n(2, H2 pca = pyrazole-3-carboxylic acid) has been prepared by dissolving a dinuclear Cu complex Cu2(py)3(pca)2(H2O)·(H2O)(1) in DMSO solution and structurally characterized by X-ray diffraction. The polymer crystallizes in space group P1 with a = 9.538(3), b = 9.714(3), c = 10.765(3) A, α = 86.492(6), β = 84.007(7), γ = 82.592(6)o, Mr = 1079.04, V = 982.4(5) A3, Z = 1, Dc = 1.824 g/cm3, μ = 2.425 mm-1 and F(000) = 548. The final refinement gave R = 0.0785 and w R = 0.1940 for 2787 reflections with I > 2σ(I). The structure of 2 consists of Cu4(pca)4(H2O)2(DMSO)2·2DMSO·2H2O units, which can be viewed as two dinuclear subunits of Cu2(pca)2(H2O)2 and Cu2(pca)2(DMSO)2 connected to each other alternately, with solvent DMSO and H2 O molecules around. The framework features a grid-like topology, with the walls of the grids composed of Cu4(pca)4 units, and the coordinated solvent molecules trapped in the grids.