Ligand stabilized gold nanoparticles with a small core size (dpossible as interest CORE< 2 nm) have generated a great deal of building blocks for nanoelectronic devices that operate at room temperature. Traditionally, methods available to prepare gold nanoparticles produce only organic soluble species passivated by phosphine and chloride ligands (e.g. Au55(PPh3)12Cl6) or by thiol ligands (e.g. Ausolubilities. A new approach nanoparticles with a wider range of 64(SR)34). It is our desire to prepare employs a biphasic ligand exchange reaction in which an entering water-soluble thiol ligand (mercaptoethanesulfonic acid and (N,N-dimethylamino)ethanethiol hydrochloride) replaces the phosphine and chloride ligands of the Au55(PPh3)12Cl6 nanoparticles. This method provides a general approach to water-soluble gold nanoparticles containing a variety of passivant ligand shells. Characterization of these nanoparticles to determine composition, size, and dispersity involves a combination of 1H and AFM, and TEM. The nanoparticles are seen to preserve the small core 13C spectroscopies, XPS, UV-visible spectroscopy, size of the phosphine parent and display marked stability over the phosphine stabilized starting nanoparticle. Future work discussing methods of rational assembly of these nanoparticles will be presented.
Green chemistry applies a set of principles that reduces or eliminates the use or formation of hazardous substances in the design, manufacture and application of chemical materials. Although green synthesis and manufacturing methods are beginning to find application in industry, few examples of green chemistry experiments are available for use in the organic teaching lab. We have developed a two-term series of experiments and supporting lecture material based upon the recent advances in green chemical methods. We will describe the curriculum and present the approach that we took in selecting, testing and optimizing the lab experiments for this course. In addition, the advantages of this curriculum will be emphasized, including improved laboratory safety, reduced wastestream, more realistic macroscale reactions, use of state-of-the-art green chemical concepts (e.g. recycling, hazard reduction, solvent reduction), and a platform for discussion of environmental issues in the classroom.