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Characterization of two series of nitrogen-containing dendrimers by natural abundance 15N NMR

✍ Scribed by Rodolphe Deloncle; Yannick Coppel; Cyrille Rebout; Jean-Pierre Majoral; Anne-Marie Caminade

Publisher
John Wiley and Sons
Year
2008
Tongue
English
Weight
191 KB
Volume
46
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

Two series of small generation dendrimers built with phosphorus atoms at each branching point and various types of nitrogen atoms at natural abundance of ^15^N within the branches are characterized by a gradient enhanced GHNMQC (gradient hydrogen–nitrogen multiple quantum coherence) ^1^H^15^N NMR technique. The first series contains two types of nitrogen atoms, included in phosphorhydrazone linkages (CHNNMeP(S)), whereas the second series contains four types of nitrogen atoms included in azobenzene linkages (ArNNAr′) in addition to the phosphorhydrazone. The influence of the trans/cis isomerization of the azo bond on the ^15^N NMR has also been studied. Despite the low solubility of the azobenzene‐containing dendrimers, which renders the detection of some signals difficult, ^15^N NMR appears as a very sensitive tool to detect chemical changes in the dendritic structure. Copyright © 2008 John Wiley & Sons, Ltd.

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