"Click" Assembly of Carborane-Appended Polymers and Stabilization of Gold and Palladium Nanoparticles

• Published in: European Journal of Inorganic Chemistry 2011-07, Vol.2011 (20), p.3043-3049
• Main Authors: Liang, Liyuan, Rapakousiou, Amalia, Salmon, Lionel, Ruiz, Jaime, Astruc, Didier, Dash, Barada Prasanna, Satapathy, Rashmirekha, Sawicki, James W., Hosmane, Narayan S.
• Format: Article
• Language: English
• Subjects: Carboranes; Click chemistry; Nanoparticles; Polymers; Polystyrene
• ISSN: 1434-1948; 1099-0682
• DOI: 10.1002/ejic.201100360

o‐Carborane was covalently linked to the side chain of a polystyrene polymer by the “click” reaction to provide acarborane‐appended polystyrene polymer. The initial step involved the radical polymerization of p‐chloromethylstyrene with AIBN followed by replacement of the chloro units by azido groups; the final step employed the CuI‐catalyzedHuisgen‐type “click” reaction between the azidomethyl‐appended polystyrene polymer and the ethynyl‐terminated carborane unit yielding the desired carborane‐appended polystyrene. Size exclusion chromatography (SEC) of this carborane‐appended polymer showed a polydispersity index (PDI) of 1.52. Dynamic light scattering (DLS) in dichloromethane provided a diameter value of 4.5 nm. The MALDI TOF mass spectrum exhibited a series of single peaks culminating from 16 carborane‐appended styrenyl units. The thermogravimetric analysis (TGA) showed the polymer to have good thermal robustness. Polymer‐stabilized gold and palladium nanoparticles (AuNPs and PdNPs) were synthesized with sizes determined by TEM to be 2.6 ± 0.4 and 1.7 ± 0.3 nm, respectively. The Miyaura–Suzuki cross‐coupling of phenyl iodide with phenylboronoic acid at 22 °C was catalyzed by the polymer‐stabilized PdNPs. “Click” o‐carborane‐appended polystyrene polymers were assembled and stabilize goldand catalytically active palladium nanoparticles.