Clickable dendronized copolymers for introducing structural heterogeneity

A new class of shape-persistent dendronized copolymers 1[Gn]4–5(a–d) (n = 1, 2) with an alternating structure was synthesized via a combination of conventional radical copolymerization and Cu(I)-catalyzed click reaction (i.e. CuAAC). Firstly, azide-functionalized dendronized copolymers 1[Gn]4-N3 that could be used as “clickable” single molecular platforms were synthesized through two steps: (i) the preparation of methanesulfonate-modified copolymers by a radical copolymerization of styrene derivatives pendant with Percec-type polyether dendron and methanesulfonate-containing maleimide; (ii) the replacement reaction of methanesulfonate unit with sodium azide. Then a series of functional molecules bearing an alkyne group, respectively, such as anthracene and mini-dendritic wedges, were attached onto each maleimide unit of the copolymers through CuAAC. Moreover, a postmodification of the denpols bearing anthracene has been conducted using Diels–Alder cycloaddition between the attached anthracenes and the maleimide dendron, demonstrating that more complicated denpols can be fabricated. These novel dendronized copolymers have been characterized by nuclear magnetic resonance spectroscopy, atom force microscopy, Fourier transform infrared spectroscopy, UV–vis spectroscopy.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Azide-modified dendronized copolymers were used as “clickable” single molecular platforms. ► Post-polymerization modification of dendronized copolymers via CuAAC and Diels–Alder reactions. ► Dendronized copolymers with heterogeneous composition were fabricated in a controlled way.