Bicyclic polystyrene was prepared by combining atom transfer radical polymerization and click chemistry. The bicyclic polymer was separated from concurrently produced acyclic (branched) polymers through fractional precipitation, and its purity was quantified by two-dimensional liquid chromatography analysis. The structure of bicyclic polymer was characterized by SEC, MALDI–TOF MS, 1H NMR, and FT-IR.

Nonlinear polystyrenes (PS) with similar molecular weights but with different molecular structures having star-, figure-8-, and cage-shaped architectures were synthesized by combining atom transfer radical polymerization (ATRP) and click chemistry. Figure-8- and cage-shaped PS were fractionated by using a gradient normal phase liquid chromatography as confirmed by SEC-LS, MALDI–TOF MS, 1H NMR, and FT-IR spectrometry. Their purities were estimated by using a two-dimensional liquid chromatography (2D-LC). The glass transition temperatures of these topologically different polymers were in the order of cage-, figure-8-, and star-shaped polymers possibly due to the multiple links that constrain the overall molecular diffusivity in the case of multicyclic polymers (figure-8, and cage). Monte Carlo simulation on the glass transition behavior of model system also agreed well with the experimental results.

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Phenyl-terminated polybutadienes (PtPBs) are efficiently converted to azidated PtPBs using the Zhdankin reagent generated in situ from iodosobenzoic acid and TMSN3 with an iron catalyst.

The copper‐catalyzed azide alkyne 1,3‐cycloaddition (CuAAC) reaction has received enormous attention as a powerful tool to form 1,4‐disubstituted‐1,2,3‐triazoles easily and conveniently. Particularly, an efficient protocol of the CuAAC reaction for regioselective double ligation through differentiating the reactivity of an azide or alkyne group is interesting for application in chemical biology, material science and pharmaceutical research. Herein, a simple competitive CuAAC reaction in water using miscibility difference of alkynes with water was discovered. Under conventional CuSO4‐NaAsc catalysts, the CuAAC reaction between a water‐insoluble alkyne and an organic azide furnished a wide range of triazole adducts primarily based on a hydrophobic effect in good‐to‐excellent yields even in the presence of a water‐soluble alkyne. This protocol provides environmentally friendly conditions for aqueous medium, easy and convenient access to triazoles without specially designed ligands for the activation and stabilization of the Cu catalyst and thus is applicable to various fields of chemistry.