Syntheses, Crystal Structures and Characterization of Two New Cadmium（II） Arsonates

Two cadmium arsonate coordination polymers, Cd(HL1)2 (1, H2L1 = 4-aminophenylarsonatic acid) and Cd(H2L2)2·2H2O (2, H3L2 = 2-(4-arsonphenylamino)acetic acid), have been synthesized and characterized by IR and single-crystal X-ray diffraction. Crystal data for 1: triclinic, space group P1 with a = 5.7559(12), b = 7.0903(14), c = 8.9925(18), α = 89.04(3), β = 80.79(3), γ = 85.09(3)o, Dc = 2.496 g·cm-3, μ = 6.095 mm-1, F(000) = 260, Z = 1, the final R = 0.0574 and wR = 0.1376 for 1489 observed reflections with I > 2σ(I). And those for 2: monoclinic, space group P21/c with a = 4.7595(10), b = 9.925(2), c = 22.609(5), β = 91.81(3)°, Dc = 2.167 g·cm-3, μ = 4.168 mm-1, F(000) = 684, Z = 2, the final R = 0.0335 and wR = 0.0815 for 2340 observed reflections with I > 2σ(I). The structure of 1 shows a two-dimensional layer consisting of inorganic chains of {CdN2(AsO3)2} along the a axis linking with the phenyl groups. These layers are further linked through strong interlayer hydrogen bonding interaction to form a three-dimensional hydrogen bond supramolecular architecture. Compound 2 has inorganic chains of {CdO2(AsO3)2} similar to 1, which connect with four adjacent inorganic chains forming a three-dimensional framework.