Self-Assembly And Catalytic Property Of The Metal-organic Compounds Based On Ag, Cd And Fe

The reactions catalyzed by transition metal have attracted a lot of consideration due to easily getting the starting materials, mild reaction and easily building complicated ring system. The supramolecular chemistry is a more complex and highly ordered system constructed by two or more moleculars through intermolecular interactions. The interaction between host and guest is the base of molecule recognition and catalysis. How to introduce transition metal into supramolecular chemistry and combine both advantages in order to achieve good catalytic activity has became a hot topic recently.1. A new’Trinity’helix complex1was synthesized based on C3-symmetric ligand L1and Ag(Ⅰ). Heterogenous isocyanoacetate aldol reaction of aldehydes was studied in CH2Cl2at room temperature. Under optimal conditions, high conversion (>99%) and high diasteroselectivities (up to80%) were obtained. When added chiral quinine during the synthese of complex1, complex2was obtained. The CD spectrum shows that complex2has chiral structure. And then we studied heterogenous isocyanoacetate aldol reaction. Under optimal conditions, reasonable conversion (up to80%), high diasteroselectivities (up to88%) and high enantioselectivities (up to almost100%) were obtained.2. A new two-dimensional Cd-MOF (complex3) was synthesized based on C3-symmetric L2. The MOF has a one-dimensional pore with a big window size of24.2×12.8A. Heterogeneous catalytic cyanosilylation of aldehydes was studied in CH2Cl2at room temperature. The kinetic curve shows that the cyanosilylation of aldehydes catalyzed by complex3consistents with first order reaction, with a rate constant of0.023min-13. A new dinuclear helix complex4was synthesized based on C2-symmetric ligand L3and Fe(Ⅱ). The CD spectrum showed that complex4has chiral structure. Homogeneous catalytic cyanosilylation of benzaldehyde and4-methoxy-benzaldehyde were studied in CH2Cl2at room temperature:a yield of almost100%obtained after11h with moderate enantionselectivities (up to86%and71%respectively). The magnetic measurements show that weak ferromagnetic interaction exists between Fe(Ⅱ) ions in one molecular.