| The design of metal-containing building blocks to spontaneously assembly into interesting molecular architectures is of considerable interest in view of the nature of magnetic exchange interactions between metal ions through bridging ligands. A successful strategy leading to one-, two-, and three-dimensional (1D, 2D, 3D) systems is the using of metal cations of link reactively stable coordination compounds containing potential bridging blocks, i.e. the"complex"as ligand approach. Acylamino-Schiff bases containing phenol-oxygen groups and amido groups are good versatile organic ligands, which can chelate as well as bridge metal ions to construct discrete and extended structures, further forming 1D, 2D or 3D structure polymers. They should play an important role for the study of coordination complex property.In view of reasons above and from the standpoint of molecular design, we have designed and synthesized mononuclear complexes, supramolecular architecture with channels and heterometal polymers of asymmetrical acylamino-Schiff bases. These compounds were characterized by X-ray crystallography, spectroscopic, thermal and magnetic properties. The main contents are described as following:(I)According to the principle of ester aminolysis, we have prepared the compound [N-(2-Hydroxybenzamido)-N'-(3-amino)dimethylmethane], and the asymmetrical acylamino-Schiff base ligand (H4L) containing carboxyl and phenol-oxygen groups.(II)Using mononuclear ligand H4L and Cu(ClO4)3·6H2O, we have synthesized copper mononuclear complex K2CuL. Through the selfassembly of mononuclear complex K2CuL and M(ClO4)2·6H2O(M=Cu,Co), we obtained 1D infinite chain-structure polymer {[Cu2·(CuL)2]·[Cu2·(CuL)2·2 H2O]}n and 2D heterotrimetallic complex {[Co·(CuL)2]·[K2·2C2H5OH]}n. Their crystal structures have been determined by X-ray analysis. Magnetic susceptibility measurements indicate that the interaction between ions is antiferromagnetic.(III)Using mononuclear complex K2MnL as precursor and Ln(ClO4)3·6H2O (Ln=Gd,Dy,Er,Ho), we have synthesized a series of homometal cagelike clusters [Ln6(HL)6·2(μ3-H2O)·CH3OH]. These complex were characterized by X-ray crystallography, spectroscopic, thermal and magnetic properties.(IV)Using analogical mononuclear complex K2NiLe and Gd(ClO4)3·6H2O, where H4Le=[N-(2-Hydroxybenzamido)-N'-(2-amino)ethane], we obtained supramolecular architecture with channels [(NiLe)4·Gd2.67·8.5H2O]2. And the complex structure was studied by X-ray, elemental analysis and IR spectra.
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