Wednesday, June 25, 2008
Congressional Room (Capital Hilton)
177

2008 HANCOCK AWARD RECIPIENT: Utilization of Linear-Dendritic Copolymers as Aqueous Nano-Reactors for Greener Cycloaddition, Oxidation and Polymerization Syntheses

Arsen Simonyan, State University of New York, Syracuse, NY and Ivan Gitsov, Institute for Polymer Research, Syracuse, NY.

The general scope of this study is the development of a supramolecular device that can be modified to serve as an efficient nano-scale reactor for organic reactions operating at green conditions. The reactions investigated have gradually become a key to a number of important materials for both the fine synthesis and the multi-ton scale industry thus emphasizing an increasing need for cheap, high yield and environmentally friendly synthetic procedures. Our first strategy employs previously synthesized linear-dendritic block copolymers, based on benzyl-ether dendrons and poly(ethylene oxide), as the sole building blocks of self-assembled well-defined nano-reactors for model aqueous Diels-Alder and [4+4]-addition reactions that involve the practically water-insoluble reactants: fullerene[60], anthracene and naphthacene. The second approach involves the construction of nano-containers with embedded biocatalyst. The same linear-dendritic copolymers are used to envelop the enzyme laccase and form a stable complex in water. This nano-construct enables aqueous oxidation and/or polymerization reactions of hydrophobic compounds like anthracene, fullerene[60], curcumin, bisphenol A, steroids, to name a few. The results obtained in both strategies show that significant improvement of the rates could be achieved, leading to generally higher yields in shorter times than previously reported, with no organic solvents required during the reactions. In addition, the results obtained at this time further substantiate the environmental benefits of the strategies used by overall lower energy consumption, usage of non-toxic, renewable and/or recyclable reaction media and catalysts, simple recovery of reaction products, and last but not least, potential for easy transfer of technology to other substrates and reactions.