Controllable Synthesis,Properties And Reactivity Studies Of Group 11 Metal Clusters

Metal clusters have attracted much attention and extensive researches owing to their structural diversity,plentiful physical properties and chemical performances.In this area,one of critical objectives should include controllable synthesis of metal clusters and understanding the relationship between the structure and property of metal clusters.In this dissertation,we have developed the macrocyclic outer-template and the multi-anionic inner-template methods for realizing controllable synthesis of group 11 metal clusters.We have also conducted in-depth exploration of the metal cluster-based self-assemblies and cluster-involved organic transformations.The following results have been achieved:(1)The bonding process between azacalix[n]pyridines(Py[n])and silver ions was systematically studied by using single crystal X-ray diffraction and various spectroscopic methods and the positive cooperativity effect was found in this process.Based on this finding,we have achieved the efficient synthesis of silver-acetylide clusters with a supramolecular triangular prism architecture.Furthermore,we have also expanded the macrocyclic outer-templated method to other metal ions,central anions and macrocycles with different sizes.(2)Taking into account the ratio between metal ions and the central anion is regulable in macrocycle-protected metal clusters,a novel nanoparticlization method for the synthesis of silver-sulfide nanoparticles with high Ag/S ratio was developed.The band gap of as-prepared silver sulfide nanoparticles was larger than those prepared from conventional methods.Based on the controllable synthesis of silver-acetylide clusters,we have successfully conducted multi-metal assisted intramolecular cyclization through introducing amino-and hydroxyl-group in the alkynyl substrates.The multi-metalated hetero-aromatics with various hetero-aromatic skeletons could be stabilized by a macrocycle.All these reaction intermediates have been fully characterized.Theoretical calculations proved the importance of aromaticity and multi-centered bonds in the stabilization of the as-prepared organometallic clusters.(3)By adopting deprotonated chiral 1,2-diamines as an inner template,a series of chiral gold clusters were synthesized and the spatial arrangements of gold atoms were characterized by single crystal X-ray diffractions.Circular dichroism measurements and theoretical calculations indicated the strong chiroptical responses were originated from the chiral inorganic core of the clusters.We had also used acetylenic carbon clusters as the inner template for the construction of high-nuclearity silver clusters with infinite onedimentional ladder type and ring type architectures.These results consolidated that the arrangement of anion centers in organic anions could dictate the metal cluster motifs.The research in this dissertation not only contributes to the controllable synthesis of metal clusters,but also explores the applications of metal clusters in supramolecular selfassembly and functional material preparation.The multi-metallic transformation provides a new available method for the design of multi-metallic catalysis in the future.