Hyperbranched polymers are obtained through one-step polymerization reactions and exhibit properties that are very similar to those of perfect dendrimer analogues. Therefore, hyperbranched polymers are a suitable alternative for perfect dendrimers as building blocks for dendritic nanocarrier systems. With regard to using soluble hyperbranched polymers as carrier systems, their flexible chains are a major benefit as they can adopt and compartment guest molecules. Upon encapsulation, the properties of the host decides the fate of the guest, e.g., solubility, but the host can also shield a guest from the environment and protect it, e.g., from degradation and deactivation. With regard to the advantages of using hyperbranched polymers as nanocarrier systems and their scalable synthesis, we will discuss different types of hyperbranched polymers and their application as nanocarrier systems for drugs, dyes, and other guest molecules.

The synthesis and characterization of a new family of dendritic polymers comprising a hyperbranched polyamidoamine core and polyethyleneglycol-derivative units is reported. The mentioned polymers have either core-shell or core-multishell architectures. Their intrinsic properties (solubility in a wide range of solvents, ability to interact with hydrophilic or hydrophobic compounds, etc.) allows the one-step in situ synthesis of water-soluble ZnO quantum dots via decomposition of an organometallic precursor. The effect of structural properties of the polymer (nature of the shell, core molecular weight, etc.), as well as external stimuli (temperature, ionic strength, etc.) on the formation and/or stabilization of nanoparticles has been evaluated. The as-synthesized nanoparticles could be easily redispersed in various solvents and presented stable photoluminescent properties.

A new enantioselective rhodium-catalyzed domino reaction is described that gives access to fused heterocycles by desymmetrization of alkyne-tethered cyclohexadienones. Two new C-C bonds and two stereocenters are formed in one step with good enantioselectivity. In contrast to prior reports, it was found that a vinylidene is not involved in the product formation but that syn-addition of the rhodium-aryl species onto the alkyne takes place.

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