'Click' functionalization of cryogels conveniently verified and quantified using high-resolution MAS NMR spectroscopy

Wim Van Camp; Tugba Dispinar; Bart Dervaux; Filip E Du Prez; José C Martins; Bernd Fritzinger

doi:10.1002/marc.200900087

'Click' functionalization of cryogels conveniently verified and quantified using high-resolution MAS NMR spectroscopy

Macromol Rapid Commun. 2009 Aug 3;30(15):1328-33. doi: 10.1002/marc.200900087. Epub 2009 May 20.

Authors

Wim Van Camp¹, Tugba Dispinar, Bart Dervaux, Filip E Du Prez, José C Martins, Bernd Fritzinger

Affiliation

¹ Polymer Chemistry Research Group, Department of Organic Chemistry, Ghent University, Krijgslaan 281, S4, 9000 Ghent, Belgium.

PMID: 21638387
DOI: 10.1002/marc.200900087

Abstract

Chemical modification reactions of alkyne containing polyHEMA-based macroporous network structures (cryogels) by Cu(I) catalyzed azide-alkyne 'click' cycloaddition reactions and their monitoring and quantification with high-resolution magic angle spinning (hr-MAS) NMR spectroscopy are reported. Complete conversion is obtained when benzylazide is reacted with the grafted alkyne function, but only partial conversion is observed when using azide-modified poly(ethylene glycol) (PEG-N(3) ). Subsequent addition of benzylazide consumes all remaining alkyne groups. All chemical modifications are easily monitored at each stage using hr-MAS NMR spectroscopy. The alkyne functionality and the resulting triazole ring provide well resolved (1) H resonances to monitor and quantify the progress of such 'click' reactions in general.