Synthesis of Boltorn 1,2,3-triazole dendrimers by click chemistry (pages 3748–3756)
Alan R. Katritzky, Yuming Song, Rajeev Sakhuja, Reena Gyanda, Nabin K. Meher, Ling Wang, Randolph S. Duran, David A. Ciaramitaro and Clifford D. Bedford
Article first published online: 10 JUN 2009 | DOI: 10.1002/pola.23427
Hyperbranched aliphatic polyols namely Boltorn® H20, Boltorn H30, and Boltorn H40 were first activated by endcapping with azido and acetylenic groups in good to excellent yields (75–95%). The resultant terminally functionalized dendritic azido and acetylenic groups undergo 1,3-dipolar cycloaddition using methyl (or ethyl) propiolate and benzyl azide, respectively, under catalytic or non-catalytic conditions below 40 °C to yield 1,2,3-triazole dendrimeric polymers in 82–95% yield, under extremely mild conditions that could be applied for compounds sensitive to acid, base, or heat. The characterization of all the Boltorn derivatives was done using 1H NMR, 13C NMR, GPC, and elemental analysis. The dendritic azido and activated acetylenic derivatives may act as novel scaffolds to tune the mechanical properties of different polymers.