H. Ihre, A. Hult, J. Fréchet
Jun 9, 1998
Citations
1
Influential Citations
230
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Quality indicators
Journal
Macromolecules
Abstract
The fourth generation tridendron dendrimer based on 2,2-bis(hydroxymethyl)propionic acid (bis-MPA) with 48 hydroxyl groups was synthesized in high yields using N,N‘-dicyclohexylcarbodiimide (DCC) for the coupling steps. A double-stage convergent approach reduced the number of synthetic and liquid chromatographic steps required in the synthesis and purification of the final dendrimers. The hydroxyl functional dendrimer was subjected to a variety of surface modifications by reaction with different acid chlorides. The acetonide, hydroxy, acetate, n-octanoate, n-palmitoate, and benzoate end-functionalized dendrimers showed large differences in thermal and solution behavior depending on the nature of their end groups. The glass transition temperature varied from −4 °C for the acetate-terminated dendrimer to +57 °C for the hydroxyl-functionalized dendrimer. Dendrimers terminated with long alkyl chains were highly soluble in hexane and dichloromethane and poorly soluble in water and methanol whereas the hydroxy-...