The characterization and deprivatization of catenane gold nanoparticles

• Main Author: Kern, Eric R.
• Other Authors: Lang, Patricia L.
• Format: Others
• Published: 2011
• Subjects: Nanoparticles.; Catenanes.; Gold.
• Online Access: http://cardinalscholar.bsu.edu/handle/handle/188011; http://liblink.bsu.edu/uhtbin/catkey/1314331

We plan to form and characterize surface-attached catenane gold nanoparticles. The proposed catenane self-assembles when a pi-electron-rich bis(thiol)hydroquinone derivative (hereby referred to as the dithiol) threads through a pi-electron-deficient inorganic molecular square forming a charge-transfer complex in solution and then attaches itself to a particle via two gold-sulfur covalent bonds.In preparation of this goal, an inorganic molecular square had to be synthesized. We synthesized, recrystallized, and characterized a cationic, tetranuclear, Pd(II)-based macrocyclic square according to the procedures published by Stang2.Then various methods of synthesis and derivatization of gold nanoparticles were investigated. Using a two-phase method published in the literature, dodecanethiolderivatized nanoparticles were synthesized,8 and attachment of the dodecanethiol was confirmed by NMR, IR, and UV/Vis spectroscopy. After the confirmation of the model compound, the reaction scheme was scaled-down for the derivatization of the nanoparticle with the dithiol alone which will be one of the components that will form the proposed catenane.Upon the derivatization of the nanoparticle with the dithiol, there was great difficulty in dissolving the nanoparticles in any polar or non-polar solvent. This led us to believe that nanoparticles are cross-linking with each other and therefore not dissolving. However, the attachment of the dithiol to the nanoparticle was confirmed by infrared spectroscopy. To solve the cross-linking problem an exchange reaction was conducted between the dodecanethiol-derivatized gold nanoparticles and the dithiol in a modified procedure from the literature.18 Although a successful exchange was confirmed by infrared spectroscopy, the dithiol-derivatized gold nanoparticles were still not soluble in any suitable solvent. === Department of Chemistry