ORGN 319 |
| Shih-Ching Chuang, Department of Chemistry and Biochemistry, University of California, Los Angeles, 405 Hilgard Ave, Los Angeles, CA 90095-1569 and Yves Rubin, Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095-1569. |
| This project focuses on generating an opening in the carbon shell of C60 by saturating a six-membered ring via addition of reactive moiety to the third C=C bond of a bisisobenzofuran system. However, due to the insufficient HOMO/LUMO coefficients of the last double bond to be saturated, we have opted to modify the electronic structure of the isobenzofuran adduct by Bingel and Prato reaction. The demand of HOMO/LUMO coefficients at this position is required in order to achieve the third saturation. Sequential modification of the C60 structure via mono-Bingel or mono-Prato addition exerted a change of the HOMO/LUMO coefficients of the third double bond dependent upon the position of the addition. We have found a tris-Bingel and tris-Prato cis-1 bisisobenzofuran adduct, namely trans-4, trans-4, trans-4 adduct, with great HOMO/LUMO coefficients. Interestingly, further introduction of the fourth Bingel adduct at the trans-1 position reduces the HOMO/LUMO coefficients. Likewise, electronic modification of the open bislactam with Bingel or Prato addend predicts a HOMO/LUMO change at the enamide C=C bond. For example, a tris-Bingel adduct of open bislactam predicts an opportunity of carrying out nucleophilic attack on the conjugated enamide C=C bond otherwise not possible because of the absence of HOMO/LUMOs. This electronic modification strategy has not only lead us to synthesize potential derivatives which are probable precursors to open C60 but also provided a technique to control the HOMO/LUMO coefficients at the C=C of interest on the C60 sphere. A detailed analysis of the effects of stepwise Bingel and Prato addition on the HOMO/LUMO structures of these derivatives will be presented. |
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Physical Organic, Combinatorial, Materials, Molecular Recognition
8:00 PM-10:00 PM, Tuesday, March 30, 2004 Anaheim Convention Center -- Hall A, Poster
Division of Organic Chemistry |
