Synthesis And Exploring Performances Of Water-soluble Coordination Macrocycles And Coordination Cages

Water-soluble metal-organic coordination macrocycles and coordination cages had potential applications in many areas,such as host-guest recognition,catalysis,and drug delivery,due to their hydrophobic coordination cavities.By using suitable coordination units,not only a series of flexible and water-soluble metal-organic coordination macrocycles and metal-organic coordination cages were prepared,but also their controllable transformations were realized driven by suitable external stimuli such as counter-anions and guest molecules.This dissertation includes the following four parts:In the introduction,the synthetic strategies and properties of water-soluble metal-organic coordination macrocycles and metal-organic coordination cages were briefly introduced.In chapter I,twelve flexible M₂L₂ type metal-organic coordination macrocycles 1-12were synthesized through self-assembling palladium salts with different steric hindrance and counter-anions and linear ligand(1,4-bis(imidazol-1-ylmethyl)benzene,bmb).The as-synthesized coordination macrocycles contain six different conformations:cis-cis helix,cis-trans helix,trans-trans helix,boat type,chair type,and planar hexagon.Induced by the trifluoromethanesulfonate anions,the macrocycle with planar hexagonal conformation can be transformed into the macrocycle with chair conformation.Driven by suitable guest molecules such as phenanthrene,the macrocycle with planar hexagonal conformation could not only be transformed into the macrocycle with cis-trans helix conformation,but also form a stable encapsulated complex combined with the guest molecules;based on this property,the efficient separation of phenanthrene and anthracene isomers could also be realized.In chapter II,a water-soluble M₆L₄ type metal-organic coordination cage 13 was synthesized through reacting with a flexible tripod ligand(tri-((pyridin-4-yloxy)methyl)ethane,tpome)and palladium nitrate cis-capped by2,2-bipyridine.The controllable deformation of the coordination cage 13 also could be realized through the regulation of counter-anions.By means of the hydrophobic cavity of the coordination cage,not only could the aromatic guest molecules be selectively encapsulated,but also the anthracene and phenanthrene isomers could be separated efficiently.In chapter III,the controllable synthesis,structural transformation,and host-guest chemistry of coordination macrocycles and coordination cages were summarized in detail,and the future research work was also prospected.