New Water-soluble Hydroxy Terminated Dendrimer Synthesis

Dendrimer is monodisperse macromolecule with a large number functional groups whose structure is highly branched.It can be controlled by chemical structure and its functional group as well as molecular size and molecular shape in molecular level.It is applied in biological medicine,catalyst,nanocomposite,surfactant,etc.During recently 20 years,a great number of research thesises about this topic have been published on the abroad high level academic magazine annually.Currently,the hot point in this field focuses on synthesis of dendrimer with new structure and functionalization of dendrimer available.In this paper,several kind of dendrimer have been synthesized by divergent with pentaerythritol and tetrakis(aminomethyl)methane as core respectively.The molecular structures of the products have been characterized by means nuclear magnetic resonance (NMR) and mass spectrum(MS).The result demonstrated that the structure of the synthesized dendrimers accord with theoretical structures.The synthesis wok as follows:1.Dendrimer with 8 hydroxyl on the periphery is synthesized from pentaerythritol by Michael addition reaction with acrylonitrile,alcoholysis and amidation with 2-amino-1,3-propanediol.2.Pentaerythritol is reacted with benzenesulfonyl chloride and sodium azide,then is reduced.Tetrakis(aminomethyl)methane is available.0.5G dendrimer with 8 ester on the periphery is synthesized from tetrakis(aminomethyl)methane by Michael addition reaction with methyl acrylate.The effects of reaction temperature,reaction time and ratio of reactants on the yield have been studied.3.Dendrimer with 16 hydroxyl on the periphery is synthesized from 0.5G dendrimer by amidation with 2-amino-1,3-propanediol.