Polyphenylenepyridyl Dendrons with Functional Periphery and Focal Points: Syntheses and Applications

Abstract

For the first time we report syntheses of a family of functional polyphenylenepyridyl dendrons with different generations and structures such as focal groups, periphery, and a combination of phenylene and pyridyl moieties in the dendron interior using a Diels−Alder approach and a divergent method. The dendron structure and composition were confirmed using NMR spectroscopy, MALDI-TOF mass spectrometry, FTIR, and elemental analysis. As a proof of concept that these dendrons can be successfully used for the development of nanocomposites, synthesis of iron oxide nanoparticles was carried out in the presence of thermally stable dendrons as capping molecules followed by formation of Pd NPs in the dendron shells. This resulted in magnetically recoverable catalysts exhibiting exceptional performance in selective hydrogenation of dimethylethynylcarbinol (DMEC) to dimethylvinylcarbinol (DMVC).

Conformational and hydrodynamic parameters of hyperbranched pyridylphenylene polymers

“…In 2005, the synthesis of polypyridylphenylene dendrimers was reported; these dendrimers are able to capture and hold inorganic particles and, therefore, can be used for development of novel nanocomposite materials . Also, the molecular structure of polypyridylphenylene dendrimers was found to have an influence on the formation of nanoparticles …”

Proof of Concept: Magnetic Fixation of Dendron-Functionalized Iron Oxide Nanoparticles Containing Palladium Nanoparticles for Continuous-Flow Suzuki Coupling Reactions

“…As was discussed previously, the aggregation of the iron oxide NPs in the catalyst material via complexation with Pd NPs is crucial in order to respond to external magnetic fields. 44,45 Leaching of Catalytically Active Pd species. As is described in literature, the Suzuki coupling reaction is not taking place on the surface of Pd NPs but with palladium atoms that have been detracted from the NPs by oxidative addition to the aryl halogen.…”

Achievements in polycondensation and condensation polymers

“…matic dendrimers and their complexation with metals, DNA, drugs, and other compounds were investigated at length [247][248][249][250][251][252][253][254][255][256][257][258][259]. It was found that these com pounds show promise for many fields, for example, for the delivery of genes, the encapsulation of nanoparti cles by dendrimers, and the manufacture of dual action preparations.…”