Synthesis And Properties Of Stable Silver Clusters And Chiral Spontaneous Resolution Of Copper Clusters

This paper mainly introduces the following two aspects:the first is the synthesis of six Ag14 clusters by using the bidentate ligand LA and its two derivatives,three of which are RS Nonchiral ligands and two of which are R chiral ligands;the second is the synthesis of a pair of copper hydrogen cluster enantiomers by using the bidentate ligand PPh2Py.Using racemic RS-LA,RS-LANH2,RS-LABA as ligand,under the action of[(C6H5)3P]2CuBH4 as a reducing agent and PPh3 as a ligand,has obtained three Ag14 clusters crystals with a small amount of Cu atom s,which are protected by bidentate sulfur biomolecules.They belong to the crystal structure of six Ag octahedral cores and eight Ag hexahedral shell.Two Ag in the direction of triple axis are doped with a sm all am ount of Cu.Under the protection of sin gle chiral R-LA,R-LANH2,R-LABA and[(C6H4)3P]2CuBH4,three Ag14 chiral clusters were also obtained by self reduction,and three circular dichroic signals were successfully measured by circular dichroism.It is difficult to study the properties of Ag clusters because of their unstable properties.However,the properties of Ag clusters we synthesized are relatively stable and can exist at room temperature,so it is a novel example for the study of clusters to explore their properties.The determination of the structure of Ag14 will further promote the study of the structure of Ag14.and provide the corresponding basis for the future study of the mechanism and structure of clusters.In the second part,a pair of copper hydrogen clusters were synthesized under different conditions under the protection of PPh2Py.The structure is a tetrahedron composed of four copper,one hydrogen anion in the middle,three PPh2Py and three Br-ligands in the periphery form a crown like cluster,which is different from the tetrahedron structure previously reported.Some circular dichroism spectra(including VCD and ECD spectra)have been obtained through different experiments,and it is known that the chirality of benzene ring and pyridine ring is due to the inhibition of chirality in the process of crystal growth.There is no corresponding report about the cluster of chiral spontaneous resolution,which provides an important evidence for the study of the properties of copper clusters and the reaction mechanism of copper clusters.