Other Soluble Multivalent Supports in Organic Synthesis

Other Soluble Multivalent Supports in Organic Synthesis 

Cozzi and coworkers reported on the generation of soluble dendronized PEG supports with an expanded functional group capacity by combining the basic principles of dendrimer chemistry with that of PEG polymers [45]. They synthesized five different tetravalent PEG derivatives (21a-e) each of them containing interesting linking functionalities (Eig. 7.10). 

The tetraol (21c) could be recovered and recycled and throughout the reaction sequence the modified polymer support retained its usual solubility/insolubility properties. 

It should be noted, that this strategy provides only a slight improvement over the linear PEG(4600)-supports with a loading capacity of 0.4 mol g Especially the difference between a [GO] and a [Gl] (loading ca. 1 mmol g ) dendron does not justify the synthetic effort. 

The authors immobilized 1-thiolactose (36a) and 2-acetamido-2-deoxy-l-thio-)9-D-glucopyranoside (36 b) on the hexavalent support by means of irradiation 

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