Synthesis and investigation of PEG-supported amino dendrimers

PEG-supported dendrimers with high-loading capacity, excellent solubility and thermal stability have been synthesized using poly (ethylene glycol) (PEG) as soluble polymeric support, 2,4,6-trichloro-1,3,5-triazine (TCT) as dendrons and ethylenediamine as linkers with divergent method, yield 53.4%. Comparing with conventional liquid synthesis methods of dendrimers, the PEG-supported intermediates were easily isolated and purified by simple precipitating, filtering, washing with Et2O to remove the unreacted materials and low molecular by-products, which could be detected using TLC. 1H NMR and IR could be used readily to analyze the configuration of PEG-bound intermediates without detaching material from the polymer-supports in each step of the sequences in contrast to insoluble polymers as polymeric supports.