ORGN 436 |
| A new application of organoboranes as highly tunable template molecules for molecularly imprinted polymers (MIPs) is described. The interaction between Lewis acidic boranes and Lewis basic phosphines is strong and directional and can be tuned by electronic and steric effects of the substituents, although it remains easily cleavable upon introduction of small amines. The hydroboration of symmetric alkynes, such as diphenylacetylene, with dialkylborane and dialkoxyboranes can be controlled to yield the corresponding alkenylborane with a remaining degree of unsaturation. Such molecules can be further functionalized by a second hydroboration step to yield fully saturated diborane compounds. This work aims to prepare 1,2-diboranes through steric and electronic control of the second hydroboration. Diborane templates can then be complexed to monodentate phosphine monomers which, upon cross-linking polymerization and subsequent template removal, can yield highly porous imprinted materials. Furthermore, the use of diborane templates should allow for specific relative spatial orientation of the two phosphine moieties within the MIPs' lined functional cavities. Hence, applications such as continuous flow enantioselective catalysis and chiral separations can be envisioned. |
|
Heterocycles and Aromatics, Molecular Recognition and Self Assembly
8:00 PM-10:00 PM, Tuesday, April 8, 2008 Morial Convention Center -- Hall A, Poster
Division of Organic Chemistry |