First synthesis and characterization of organoplatinum dendritic necklaces and dendritic networks using an outer sphere-outer sphere connection strategy

This thesis described the first report of the use of surface bi-functionalized and tri-functionalized dendrimer subunits as monomers for the construction of three different classes of novel dendrimer-based polymers via an outer sphere-outer sphere connection strategy.; The first part of this thesis illustrated the convergent syntheses and characterizations of a series of surface bi-functionalized dendrimers 116–118 (G1 to G3). Subsequent co-polymerization of these dendritic monomers via their surface acetylene functionalities in the presence of dichlorobis(triethylphosphine)platinum(II) yielded linear organoplatinum dendritic co-polymers (also called dendritic necklaces) 163–165 . Laser light scattering and size exclusion chromatographic analyses revealed that these dendritic necklaces had a very high molecular weight and a high degree of polymerization (up to 880 repeating units). The structure and purity of the precursor molecules as well as those of the dendritic necklaces were examined by 1H-, 13C-, 31P-NMR and UV spectroscopy. The thermal stabilities of the dendritic necklaces were also investigated by thermal gravimetric analysis (TGA). Their thread like morphologies were also characterized by scanning tunneling microscopic (STM) imaging.; The second part of this thesis depicted the co-polymerization of the previously described surface bi-functionalized dendrimers 116–118 in the presence of a small size branching agent 166 with the aim to prepare cross-linking organoplatinum dendritic networks. The [G1]-dendritic network 168 obtained was an insoluble dendritic gel system whose network structure was determined by energy dispersive X-ray and STM techniques. On the other hand, the [G2]- and [G3]-dendritic networks 169–170 were soluble oligomeric systems with little cross-linking. Hence the size (i.e. the generation) of the dendritic co-monomer is an important controlling element in their co-polymerization with the small size tri-platinum(II) co-monomer.; The third part of this thesis described the convergent syntheses and characterizations of surface tri-functionalized dendrimers 174–176 (G0 to G2) as monomers. In contrast to the co-polymerization described in part two, co-polymerizations of these dendritic monomers via their surface acetylene functionalities in the presence of a diplatinum(II) complex 172 successfully produced insoluble organoplatinum dendritic networks 185–187. (Abstract shortened by UMI.)...